July 2005 - The Hong Kong College of Anaesthesiologists

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005ContentsPagesEditorial63 Why Publish in the Bull HK Coll Anaesthesiol?63 Forced Air Warming using Hospital Blankets: Best for Less?Featured Articles67 Outside Qualified Anaesthesiologists Working In China (1)Clinical Investigations71 Comparison of Effectiveness between Upper and Lower Body Forced Air Warming during OpenAbdominal Surgery75 Combined Spinal Epidural Anesthesia versus Spinal Anesthesia for Cesarean Section: Effect onMaternal Hypotension83 Low‐dose Subcutaneous Ketamine Infusion: a Dose Finding Study for Post‐operative AnalgesiaPerioperative Nursing90 An audit of Perioperative Hypothermia in the Elderly PatientsCase Report95 An Epidural Abscess Following Catheter Insertion101 Novel Use of Endobronchial Tube in Management of a Patient with Giant Lung BullaCollege Business107 16 th Annual General MeetingThe Editorial Board (2005‐2007)Editor‐in‐ChiefBoard MemberMatthew ChanRebecca KwokMing Chi ChuHuey S LimBassanio LawSin Shing HoMichael PoonSC YuEric SoSteven WongTimmy YuenCarina LiEmail: mtvchan@cuhk.edu.hkAddress: Department of Anaesthesia and Intensive Care, Chinese University of Hong Kong, Prince ofWales Hospital, Shatin, NT, Hong KongPhone: 2632 2894Fax: 2637 2422DisclaimerUnless specifically stated otherwise, the opinions expressed in this newsletter are those of the author’spersonal observations and do not necessarily reflect the official policies of the Hong Kong College ofAnaesthesiologists.All rights reserved. The HKCA Bulletin and its electronic version are protected by copyright law and international treaties. Unauthorized reproductionor distribution, in whatever form or medium, is strictly prohibited. No part of the HKCA Bulletin may be reproduced, translated, stored in a retrievalsystem, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior writtenpermission of The Hong Kong College of Anaesthesiologists.Typeset and printed in Hong Kong by the Best e‐Publishing Group Limited61

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005EditorialsBull HK Coll Anaesthesiol 2005;14:63Why Publish in the Bull HK Coll Anaesthesiol?There are a number of reasons that youhave to publish in the Bull HK CollAnaesthesiol. As an official publication ofthe Hong Kong College of Anaesthesiologists,the Bulletin is distributed to over 600 individualsworking locally and aboard. We have an activeplan to extend our distribution beyond thememberships to other institutions and libraries.Articles published in the Bulletin are more likelyto be read by fellows and members than anyother journals published overseas. Eventually,your work will improve our way in practicinganesthesia, intensive care and pain medicine.The Bull HK Coll Anaesthesiol is accredited bythe College CME Sub‐committee. Normally, thefirst six authors of any scientific articlespublished in Bulletin will receive credits pointsunder the category of “Publications”. The firstauthor of each paper is credited with ten pointswhile the remaining authors are credited withfive points.We welcome manuscripts from differentaspects of our specialty. Currently, we publishFeatured Articles that describe the practice inour neighborhood. Clinical and LaboratoryInvestigations are designed to publishimportant observations, audits or results ofclinical trials and experiments. We also welcomeReviews and Case Reports for experiencesharing. There is also Letters to the Editor for usto exchange ideas and to discuss paperspublished in the Bulletin. Manuscripts submittedto Bulletin are reviewed by our “friendly”editorial board and published promptly. TheBulletin is also published online in the Collegewebsite.I hope you will agree with me that apublication in the Bulletin worth a lot more thanany other journals!Dr Matthew ChanEditor‐in‐ChiefBull HK Coll Anaesthesiol 2005;14:63‐6Forced Air Warming using Hospital Blankets: Best for Less?Unintentional perioperative hypothermia(body temperature < 36 o C) occurs inapproximately 50% of all surgicalpatients. 1‐3 The contributing factors includeimpaired thermoregulation from various formsof anesthesia, cold operating room environment,intravenous fluids, antiseptic solutions for skinpreparation and open body cavities. 4Inadvertent perioperative hypothermiapredisposes to many adverse effects on patientrecovery. It is associated with cardiacmorbidities, 5 excessive surgical blood loss, 6increased incidence of surgical wound infectionsand prolonged hospital stay. 7 It also contributedto reduced metabolism and clearance ofnumerous drugs. 8,9 More importantly, shiveringas a consequence from hypothermia is mostuncomfortable for the patient. 10Forced air warming is an effective and noninvasiveactive warming system. The electrically63

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005microbiology and clinical studies are thereforerequired to demonstrate the safety of usinghospital blanket for forced airway warming.Yee Kwan TANG, MBBSDepartment of Anaesthesia and Intensive CarePamela Youde Nethersole Eastern HospitalRebecca KWOK, MBBS FANZCA, FHKCA, FHKAM(Anaesthesiology), Dip Pain Mgt (HKCA)Department of AnaesthesiaYan Chai HospitalSin Shing HO, MBBS, MRCP, DFM, FHKCA, FANZCAUnion HospitalReferences:1. Vaughan MS, Vaughan RW, Cork RC.Postoperative hypothermia in adults:Relationship of age, anesthesia, andshivering in rewarming. Anesth Analg1981;60:746‐51.2. Frank SM, Higgins MS, Breslow MJ, et al.The catecholamine, cortisol, andhemodynamic responses to mildperioperative hypothermia: a randomizedclinical trial. Anesthesiology 1995;82:83‐93.3. Frank SM, Shir Y, Raja SN, et al. Corehypothermia and skin‐surface temperaturegradients. Anesthesiology 1994;80:502‐508.4. Sessler DI. Perioperative heat balance:review article. Anesthesiology 2000;92:578‐96.5. Frank SM, Fleisher LA, Breslow MJ, et al.Perioperative maintenance of normothermiareduces the incidence of morbid cardiacevents: a randomized clinical trial. JAMA1997;277:1127‐34.6. Schmied H, Kurz A, Sessler DI, et al. Mildhypothermia increases blood loss andtransfusion requirements during hiparthroplasty. Lancet 1996;347:289‐92.7. Kurz A, Sessler DI, Lenhardt R.Perioperative normothermia to reduce theincidence of surgical‐wound infection andshorten hospitalization. N Engl J Med1996;334:1209‐15.8. Heier T, Caldwell JE, Sessler DI, et al. Mildintraoperative hypothermia increasesduration of action and spontaneousrecovery of vecuronium blockade duringnitrous oxide‐isoflurane anesthesia inhumans. Anesthesiology 1991;74:815‐19.9. Leslie K, Sessler DI, Bjorksten AR, et al. Mildhypothermia alters propofolpharmacokinetics and increases the durationof action of atracurium. Anesth Analg1995;80:1007‐14.10. Krenzischek DA, Frank SM, Kelly S. Forcedairwarming versus routine thermal careand core temperature measurement sites. JPost Anesthesia Nursing 1995;10:69‐78.11. Sessler DI, Moayeri A. Skin‐surfacewarming: heat flux and central temperature.Anesthesiology 1990;73:218‐224.12. Sessler DI, Akca O. Nonpharmacologicalprevention of surgical wound infections.Clin Infect Dis 2002;35:1397‐1404.13. Rainer L. Monitoring and thermalmanagement. Best Pract Res ClinAnaesthesiol 2003;17:569‐81.14. Ma MS, Chiu AHF. Prevention ofinadventent hypothermia of patient aged 60or above. Bull HK Coll Anaesthesiol2005;14:90‐4.15. Lim DTH, Law BCW. Comparison ofeffectiveness between upper and lower bodyforced air warming during open abdominalsurgery. Bull HK Coll Anaesthesiol2005;14:71‐5.16. Kempen PM. Full body forced air warming:commercial blanket vs air delivery beneathbed sheets. Can J Anaesth 1996;43:1168‐74.17. Giesbrecht GG, Ducharme MB, McGuire JP.Comparison of forced‐air patient warmingsystems for perioperative use.Anesthesiology 1994;80:671‐9.18. Kabbara A, Goldlust SA, Smith CE, et al.Randomized prospective comparison offorced air warming using hospital blanketsversus commercial blankets in surgicalpatients. Anesthesiology 2002;97:338‐44.19. Avidan MS, Jones N, Ing R, et al. Convectionwarmers ‐ not just hot air. Anaesthesia1997;52:1073‐76.20. Sigg DC, Houlton AJ, Iaizzo PA. Thepotential for increased risk of infection due65

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005to the reuse of convective airwarming/coolingcoverlets. ActaAnaesthesiol Scand 1999;43: 173‐76.21. Baker N, King D, Smith EG. InfectionControl hazards of intraoperative forced airwarming. J Hosp Infect 2002;51:153‐4.22. Huang JKC, Shah EF, Vinodkumar N, et al.The Bair Hugger patient warming system inprolonged vascular surgery: an infectionrisk? Crit Care 2003;7:R13‐6.23. Tumia N, Ashcroft GP. Convection warmers‐ a possible source of contamination inlaminar airflow operating theatres? J HospInfect 2002;52:171‐4.24. Kamming D, Gardam M, Chung F.Anaesthesia and SARS. British Journal ofAnaesthesia 2003;90:715‐8.25. Fleisher L, Metzger SE, Lam J, et al.Perioperative cost‐finding analysis of theroutine use of intraoperative forced‐airwarming during general anesthesia.Anesthesiology 1998;88:1357‐64.Congratulations!!The Prize of the Intermediate Fellowship Examination, March/April, 2005, was awarded to Dr Amy KONG(KWH). Dr Kong also received a Merit Certificate from ANZCA for her achievement in the PrimaryExamination, March/April, 2005.The Prize of the Final Fellowship Examination, April/May, 2005, was awarded to Dr Katherine Lam (PWH)66

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005Featured articleOutside Qualified Anaesthesiologists Working In China (1)1Anne KwanDepartment of Anaesthesia, United Christian Hospital, Hong Kong Special Administrative RegionBull HK Coll Anaesthesiol 2005;14:67‐70After 1997, it has become a reality or evennecessity for the medical professionalqualified in Hong Kong to engage inclinical work in China. The healthcaredevelopment in Hong Kong has followed theBritish system closely and a lot of adjustmentsare required for the Hong Kong trained doctorsto practice in Mainland. The differences inhealth care are the result of the unique nature ofthe political system in China, the vastness of thecountry, the extremes of wealth distribution andthe language medium in teaching and day today communication.Despite the introduction of Closer EconomicPartnership Arrangement (CEPA), medicalprofessionals qualified in Hong Kong are notgranted with recognition and full registrationwith the relevant medical bodies in China.However, it is still possible to perform clinicalwork in there by having limited registration.The registration can be arranged by a receivingunit. The unit which is usually a hospital or theRed Cross, after vetting the qualifications of thedoctor then issues a letter of invitation. Theletter of invitation would specify the name of theinvitee, nature of the work and the period. Mostof the work is on a voluntary basis as the pay of1MB BS, FANZCA, FHKCA, Dip Pal Med, Dip PainMgt (HKCA) FHKAM (Anaesthesiology), Dip Epi &Biostat, Dip Acup, M Pal Care, Consultant and Chiefof Service. Department of Anaesthesia United ChristianHospital.Address correspondence to: Dr Anne Kwan,Department of Anaesthesia, United ChristianHospital, 130 Hip Wo Street, Kowloon. E‐mail:askkwan@yahoo.com.hka doctor in China is still not attractive ascompared to that in Hong Kong. Before onecommences work, it is sensible to obtain medicalprotection cover for clinical malpractice. Thecover can usually be arranged by theindividual’s own medical protectionorganization such as the Medical Defense Unionor the Medical Protection Society before leavingHong Kong. If the duration is not too long, theadditional cover is usually provided free as partof one’s existing insurance package.Despite Putonghua being the official spokenlanguage, it is likely that one would come acrossmany local dialects and communication can be areal problem even if you are proficient inPutonghua. The official written language issimplified Chinese characters. It is not unusualfor the local to look puzzled when traditionalChinese characters are used. The staff at themajor teaching hospitals in the big cities wouldknow English but on the other hand having aninterpreter around could be helpful. It is also agood idea to learn about the hospital one isgoing to work in. Apart from the physicalenvironment, it is important to know thequalification and experience of the staff. Theinformation on availability and charge of themedical equipment, drugs and blood and/orproducts are also helpful for one to get to knowthe system quickly.Although most parts of China are still ratherslow and under developed, rapid progress isbeing made in improving the living standards ofher people. The improvement in the health caresector is noticeable but the downside is that ofhigh health care cost. Health care service inChina is not free. Patients are paying an67

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005escalating fee for the service. In order to avoidpayment defaults, a deposit of substantialamount is required on admission to the hospital,including emergency admissions. The cost iscalculated on the number of days stay, the typeof hospital ward, the use of drugs and otherequipment, the number of investigationprocedures and nature of operation. The totalcost can mount up to an astronomical amount.Some patients actually opt not to be treatedbecause of the high and unaffordable cost.My interpretation of the Chinese medicalsystem may not reflect the places I have notbeen to as China is obviously a vast countrywith varying health care set ups and clinicalpractices. I would like to also mention that thereare a few anaesthesiologists in Hong Kong, whogo up to China to observe, work, and help withthe training of local specialists for short periodsof time on a regular basis like me. Although thehospitals we went to might be similar, we mighthave slightly different experience and interpretour experience in a different manner. I wouldlike to further point out that most of thehospitals I worked in were in the Henanprovince. Henan province is the second largestprovince in China and it has a population of 100million. Before I go on to share my limitedexperience of my clinical practice in China, Iwould like to briefly explain the few uniquesystems in there. China has unique setup for thehospital system, the training of specialists, andthe billing of patients. Also, one must appreciatethe special Chinese social culture in order tomake your work and stay more enjoyable there.The hospital systemThere are different types of hospitals in China.Although the hospitals are not classified intopublic and private hospitals as such, they are allessentially private hospitals as all patients arebilled for the health care services they receive.All the services are itemized and I would furtherexplain how billing is done in the other sectionof this article.Generally, there are two types of hospitals,the Western medicine hospitals and the Chinesemedicine hospitals. However, it is notuncommon to have a department of Chinesemedicine in the western medicine hospitals andvice versa. Some of the pharmacy departmentshave two divisions, namely the western drugdivision and the Chinese herbal division. If onewonders around the hospitals, be it named aswestern or Chinese medicine hospital, one canfollow the smell of herbs and find clay pots withherbs on the hot stoves. Some hospitals offerhigh tech herbal medicine dispensing bypreparing the herbs in electrically heated urnsfor the patients before hand and have themdistributed in plastic containers to take home forconsumption.The other naming system one often finds isthe use of names such as people’s hospital,military hospital, factory hospital, unionhospital and Red Cross hospital. All thesehospitals are public hospitals (or should we callthem private hospitals). The names reflect theassociation of the hospitals with the foundingorganizations. The association could have beenbroken some years back and the name remains.Hospitals called by the name of the city thenfollowed by a number (first, second or third etc.)are hospitals built by the government or theywere renamed after the culture revolution. Somehospitals are run by the locals with a team ofmedical experts from overseas and they arereferred as the collaboration hospitals.The clinical classification of the hospitals ismost easily understood by the ABCcategorization. All hospitals are categorized intoone of the followings: AAA, AAB, AAC, ABB,ABC, ACC, BBB, BBC, BCC, or CCC. “A”denotes the best in its class and “C” the lowestlevel. A major teaching hospital must be anAAA institution and a local small hospital withonly a few run down clinics would be a CCChealth care centre. The hospitals have to meetthe performance targets before they are grantedthe level of competence they claimed. Inspectionis carried out periodically to see if the criteriaare met. Some of the criteria the authority looksfor are the provision of accident and emergencyservice, cardiovascular surgery andneurosurgery. Other criteria are the processionof hardware such as all sorts of endoscopies, CT68

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005scan and MRI. It is interesting that one can oftenfind advertisements and banners posted all overthe place including along the highways by thehospital administration to advertise the highstandard achieved by the hospital in order toattract patients to the hospital. Often servicedevelopment of the hospital also goes along thatline. Visits by overseas medical experts to thehospital are most welcome as that reflects theservice provided by the hospital is of a higherand well known level.The specialty classification is perhaps theeasiest to understand. Some hospitals provideonly one of the specialty services such asgynecology and obstetrics, maxillofacial, cardiac,and pediatrics. The type of specialty servicewould be reflected by the names of the hospitals.Although one rarely hears of a hospital for thehepatic specialty, one can find hospitals for liverdiseases. Hospitals for the combined specialty ofeye, ENT and maxillofacial can also be found.The training systemIt is not enough to just know about the hospitalone is going to work in. In order to provide asafe and efficient service, it is mandatory toknow how one’s co‐workers are trained andtheir clinical competence. There are so manyways a doctor can be trained to become aspecialist that one needs to carefully work outtheir qualifications and experience. There arehighly qualified and immensely experiencedcolleagues around doing very impressive works.However, there are some who are trained as“technicians” and unable to cope with difficultor unusual cases. The differentiation may behard initially as some of them may be experts intheir field but remain so humble that theywould not reveal how much they know.However some of them, although not so wellqualified, would tackle every case their ownway. If one’s intention is to provide the best carefor the patients and learn from each other, it isnot too difficult to learn how much they knowand one would try to fit in. Sooner or later onecan break down the barrier.Students in China can be qualified as“medical practitioners” through variouschannels. The quickest way is to go throughmedical technical schools which provide a fouryear course for the students who havegraduated from junior or senior high schools.Most of these practitioners go to the village towork in the health care clinics. It is unlikely thatthey would be accepted to train in the specialtyfield. Most medical practitioners are trained inthe medical schools of universities or medicalschools affiliated to hospitals. They then getsend to a hospital and stay in the specialty theyare assigned. While working as residents, theyreceive training and with time they becomespecialists. Some lucky ones may spent a year orso in a larger teaching hospital in a big city andreturn to their own hospital to stay workinguntil they are allowed to retire at about age of 50years or so. The really bright or lucky oneswould be encouraged and arranged to gooverseas for specialty training for a period oftime. United States of America is obviously theplace of choice. Some do come to Hong Kong tolearn. It is getting increasing popular for some ofthe smarter younger doctors to go through aDoctor of Medicine (MD) program in order toqualify in a specialty. Apart from intensiveclinical training, research activities are part ofthe requirements in getting a MD. Only untilabout three years ago, there was no uniformclinical examination for practicing doctors inChina. Recently a post graduate writtenexamination has become compulsory for theyounger doctors to pass before they are allowedto continue to practice. This in some ways servesas some form of continuing medical educationrather than specialist qualification assessment.The examination consists of multiple choicequestions of all specialties. The across thecountry compulsory specialist assessment for allspecialties are in the preparatory stage. It washope that a more uniform approach would bringa higher standard of training and specialistqualifications that are recognized all over China.At present some of the specialist qualificationscan only be recognized within the same city oreven the training institute. It is possible as onecan fast tract and turn oneself into a “specialist”about eight years after junior high school.Whereas some medical graduates may take69

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005formal training for almost 10 years afteruniversities.After mentioning that the most preparedway of starting practice in China comes afterlearning more about the place, I actually did notdo any of that when I first went to work in asmall country hospital in China about 7 yearsago. Subsequently, I have worked in over half adozen hospitals of various sizes and standards.Most of the time, I enjoyed my short stay upthere but at times it was nerve racking. As I wasand still am an anesthesiologist by profession, Imainly anaesthetized patients while I wasworking in China. Most of my patients hadplastic procedures (cleft lips and palates or scarfrom burns) or orthopedic operations becausemost times I went with a group of plastic ororthopedic surgeons who worked with andprovided training for the local surgeons.In my next article, I would share myexperience in working in the operating theatresand the problems of using anesthetic drugs inChina.70

Clinical InvestigationsBull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005Comparison of Effectiveness between Upper and Lower BodyForced Air Warming during Open Abdominal Surgery1David TH Lim, 2 Bassanio CW LawDepartment of Anaesthesiology and Operating Theatre Services, Kwong Wah Hospital, Hong KongSUMMARYMany studies have shown that forced air warming is effective in preventing unintentional preioperativehypothermia. However, there are few data evaluating the optimal site for forced air warming. In thisprospective study, 87 patients undergoing prolonged open abdominal surgery were randomized toreceive either upper or lower body forced air warming. Nasopharyngeal and rectal temperature wasrecorded in both groups from induction of anesthesia to 3 hr after induction, the upper body forced airwarming group showed significantly higher temperature reading. The differences started from 1 hourafter induction (0.39 and 0.29 o C respectively), and persisted for 3 hours (0.73 and 0.60 o C respectively).This study showed that for patients undergoing prolonged abdominal surgery, forced air warming ismore effective when applied to the upper body than that of the lower body.Keywords: Hypothermia, Force air warming, anesthesiaBull HK Coll Anaesthesiol 2005;14:71‐5Without the use of warming devices,hypothermia is common in patientsundergoing surgery. It is nowrecognized that even mild hypothermia can leadto adverse consequences. These includemyocardial ischaemia 1 , platelet dysfunction,coagulopathy causing increased blood loss 2 ,wound infection 3 , delayed postanaestheticrecovery, 4,5 postoperative shivering and thermal1MB BS, FANZCA, FHKCA, FHKAM (Anaesthesiology),Associate Consultant 2MB BS, FANZCA,FHKCA, FHKAM (Anaesthesiology), AssociateConsultant. Department of Anaesthesiology andOperating Theatre Services, Kwong Wah Hospital.Address correspondence to: Dr David Lim,Department of Anaesthesia, Tseung Kwan OHospital, 2 Po Ning Lane, Hang Hau, Tseung KwanO. E‐mail: dthlim@gmail.comdiscomfort 6 .The efficacy of forced air warming toprevent hypothermia is well proven. It issuperior to other commonly used warmingmethods such as radiant heaters, fluid warmers,airway humidification, and circulating waterblankets. 7‐10 This has lead to the widespread useof forced air warmers, especially for majoroperations where the risk of hypothermia issubstantial. Its effectiveness has been proven fora wide variety of surgical procedures, whenapplied to either the upper or lower part of thebody 11,12 . However there is no study that directlycompares the effectiveness of forced airwarming applied to these two sites. Thereforethe application of forced air warming to theupper or lower body in patients undergoingabdominal surgery has largely been thepreference of clinicians or institutional practice.71

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005The aim of this study is to evaluate therelative effectiveness of forced air warming inpreventing intraoperative hypothermia, whenapplied to the upper or lower body in patientsundergoing prolonged open abdominal surgery.Materials and MethodsA prospective, randomized, single‐blindedstudy was conducted to compare the relativeeffectiveness of upper and lower body forced airwarming in patients undergoing prolongedopen abdominal surgery of more than 2 hoursduration.Power analysis was based on a type I errorof 0.05 and a type II error of 0.2 using the Powerand Precision computer software (Biostat, Inc.,Englewood, NJ, USA). According to the resultsof previous studies 13,14 , we calculated that atleast 42 patients per group is required todemonstrate a mean difference in core bodytemperature of 0.5 o C with a standard deviationof 0.8 o C.Approval by the hospital ethics committeeof the study was obtained. Eighty seven adultpatients, older than 18 years, American Societyof Anesthesiologists physical status I to III,undergoing open abdominal surgery with anexpected duration of more than 2 hours, wererecruited in this study. Simple randomisation ofpatients into two groups of either the upper orlower body warming was performed. Exclusioncriteria included pre‐existing hypothermia (coretemperature < 36 o C) or hyperthermia (> 38 o C),patients undergoing abdominal aortic surgery,burn injury or multiple traumatic injuries, andsurgery in lithotomy position.Preoperatively, demographic data wererecorded and tympanic membrane temperaturesof patients were recorded by infrared probe(ThermoScan Pro 1, Braun AG, Germany).All patients received general anaesthesiawith tracheal intubation. Nasopharyngeal andrectal thermistor temperature probes (Datexmodel 16561, Helsinki, Finland) were insertedafter induction of anesthesia. Thenasopharyngeal and rectal temperatures ofpatients were continuously monitored duringsurgery using the temperature‐monitoringmodule (model M‐ESTPR 00‐02) and displayedon a Datex AS/3 anesthesia monitor. The initialreadings and further readings at 15‐minuteintervals were recorded after induction ofanesthesia until the end of surgery.After baseline recordings, forced airwarming using Warm Touch model 501‐5800(Mallinckrodt Medical, St Louis, MO, USA) wasapplied to all patients for the wholeintraoperative period. For the upper body group,an “upper body blanket” (Warm Touch model503‐0820) was applied to cover the upper trunkand limbs. For the lower body group, a “lowerbody blanket” (Warm Touch model 503‐0830)was applied to cover the lower limbs up to themiddle of the thighs. The forced air warmerswere initially set to the “high” setting for bothgroups. The warmer settings were reduced tomedium or low if the core temperature exceeded37.5 o C.All intravenous and irrigation fluids usedwere warmed in fluid warming cabinet prior touse. Circle anesthetic circuits with soda‐limeabsorbers were used. The use of additionalwarming devices such as heat and moistureexchangers, intravenous fluid warming coils orcirculating water mattresses were recorded. Theambient temperature in the operating theatrewas set to 21 o C, and the temperature at the startand end of the surgery was recorded using anordinary alcohol thermometer.Statistical analysis of temperature readingswas performed using two‐tailed factorialanalysis of variance with repeated measures.Analysis of demographic data was performedwith χ 2 test for categorical variables andStudent’s t‐test for continuous variables.ResultsThe 87 patients enrolled in the study wererandomized into 45 patients in the upper bodygroup and 42 patients in the lower body group.The summary of patient characteristics is shownin Table 1. No difference was found betweenthe groups in demographic characteristics,preoperative temperature, type of surgery,ambient operating theatre temperature and72

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005Table 1. Patient characteristics. Data are presented as mean ± SD, or number of patients. ASA = AmericanSociety of Anesthesiologists; OT = operating theatre; HMW = heat and moisture exchanger; CWM =circulating water mattress.Upper Body Lower Body P valueNumber of patients 45 42Age (years) 62.1 ± 14.9 61.0 ± 16.5 0.74Sex (Male/Female) 21/24 20/22 0.93Weight (kg) 53.8 ± 10.7 54.7 ± 9.6 0.67ASA Class I/II/III 14/24/7 15/19/8 0.75Type of surgical procedure 0.68Upper gastrointestinal 11 10Lower gastrointestinal 12 16Hepatobiliary 13 10Gynecological 9 6Elective/Emergency procedure 37/8 33/9 0.67Ambient OT temperature ( o C)Start of surgery 20.3 ± 0.9 20.2 ± 0.7 0.67End of surgery 20.6 ± 0.9 20.7 ± 0.8 0.53Preoperative patient temperature ( o C) 37.5 ± 0.6 37.3 ± 0.6 0.21Intraoperative blood loss (ml) 477.1 ± 531.7 475.2 ± 556.1 0.99Time Interval (min)Induction ‐ Warmer application 14.0 ± 6.9 13.2 ± 7.2 0.59Induction ‐ Skin incision 19.5 ± 6.6 19.0 ± 6.6 0.69Induction ‐ Wound closed 185.9 ± 78.4 209.0 ± 96.8 0.22Additional warming equipment used 0.93Warming coil, HME, CWM 6 7Warming coil, CWM 9 9HME, CWM 6 4CWM 24 22intraoperative blood loss. The time intervalsfrom induction of anesthesia to application ofwarmer, from induction to incision, and frominduction to the end of surgery were similarbetween groups. There was also no difference inthe use of additional warming equipmentbetween groups.Changes of nasopharyngeal temperature inboth groups are shown in Figure 1. Thirty‐fourpatients in the upper body group and 37patients in the lower body group had surgerythat lasted over 2 hours. For the remaining 16patients, their procedure ended up taking lesstime than initially anticipated. However, basedon the intention to treat, data from all patientsthat were initially enlisted in the study wereanalysed, up till the end of their procedure orthe 180‐minute interval, whichever is earlier.The upper body group showed a significantlyhigher mean nasopharyngeal temperaturecompared with the lower body group,beginning from 60 minutes post induction ofanaesthesia, and persisting till 180 minutes postinduction.Changes of rectal temperature duringsurgery are shown in Figure 2. In common withthe nasopharyngeal temperature, rectaltemperature in the upper body group wassignificantly higher compared to the lower bodygroup, from 60 minutes post induction till 180minutes after induction of anesthesia. However,there was a difference in the number of patients73

Bull HK Coll Anaesthesiol Volume 14, Number 2 July, 2005Figure 1. Changes of nasopharyngeal temperatureafter the start of surgery. *P = 0.001; **P < 0.001.Figure 2. Changes of rectal temperature after thestart of surgery. *P = 0.02; **P = 0.001; ***P < 0.001because the rectal thermistor probe wasdislodged in 3 patients in the upper body group.DiscussionWith the increased awareness of possibleadverse effects with inadvertent hypothermia,there has been widespread adoption to the useof forced air warming. Although there havebeen many studies that proved the effectivenessof forced air warming over other methods ofpatient warming, few have compared he relativeeffectiveness of the sites of applications.This study showed that, in patientsundergoing prolonged open abdominal surgery,forced air warming is more effective whenapplied to the upper part of the body than thelower part. After an initial decrease intemperature after anesthesia, it stabilized andreturned to normothermia by 30 to 60 min in theupper body group. In contrast, the temperaturein the lower body group increased onlygradually 60 min after induction. At 1 hourafter induction, the mean nasopharyngealtemperature was 0.39 o C higher in the upperbody group. This difference increased to 0.73 o C3 hours after induction.The body surface area covered by the upperor lower body forced air warming blankets wassimilar in this study. It is postulated that theincreased effectiveness of upper body forced airwarming might be related to the betterperfusion of the upper limbs and trunkcompared with the lower limbs, especially sincepatients undergoing open abdominal surgerytended to be older.Patients undergoing prolonged openabdominal surgery were selected for this studybecause with exposure of the intestines, thelikelihood of developing hypothermia increased.Therefore, there is a better chance to detect adifference in effectiveness between the upperand lower body forced air warming.Although all patients in this study receivedgeneral anesthesia, the actual conduct ofanesthesia was not standardized. This wasdeliberately so, because we intended to test theeffectiveness of forced air warming in twodifferent sites during daily and highly variableclinical practice. It is also consideredinappropriate to standardize the use ofadditional patient warming methods, but theywere recorded and analysed as confoundingvariables. Notwithstanding this, most patients inthis study received general anesthesia withintravenous induction, followed by maintenancewith low flow inhalational anesthesia usingsevoflurane or isoflurane with nitrous oxide andoxygen mixture, supplemented withintravenous opioids and muscle relaxants.74

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Combined Spinal Epidural Anesthesia versus SpinalAnesthesia for Cesarean Section: Effect on Maternal Hypotension1KC Lui, 2 ML Wijayaratnam, 3 CT HungDepartment of Anaesthesia, Queen Elizabeth Hospital, Hong KongSUMMARYSixty healthy parturients scheduled for elective cesarean section were randomly allocated to receivespinal anesthesia (n=30) or combined spinal epidural anesthesia (CSE, n=30). In the spinal group, 2.2 ml0.5 % heavy bupivacaine and 10 μg fentanyl was injected into L2/3 space through 26G Quincke needle. Inthe CSE group, 1.5 ml 0.5% heavy bupivacaine and 10 μg fentanyl were injected intrathecally using aneedle through needle CSE set (26G Quincke and 18G Tuohy needle) at L2/3 space. Operation startedwhen T6 level was reached. Additional 1.5 ml of 0.5% plain bupivacaine per unblocked segment wasadded epidurally to achieve T6 level if necessary. Demographic data, side effects, neonatal outcome weresimilar between groups. Two patients in the CSE group and none in the spinal group developedinadequate analgesia. Hypotension occurred in 93% of parturients in the spinal group and 73% in the CSEgroups (P = 0.08). Lowest systolic arterial pressure developed later in the CSE group than the spinalgroup (P = 0.04). Ephedrine consumption was greater in the spinal group (P = 0.03). We concluded thatCSE anesthesia provided surgical anesthesia in cesarean section as effective as spinal anesthesia using 7.5mg bupivacaine with 10 μg fentanyl. CSE also reduced the incidence of hypotension.Keywords: Combined spinal epidural anesthesia, fentanyl, hypotensionBull HK Coll Anaesthesiol 2005;14:76‐82Regional anesthesia is a popular techniquefor elective cesarean delivery. It avoidsthe risks of failed intubation andaspiration associated with general anesthesia.1MB ChB, FHKCA, FHKAM (Anaesthesiology).Senior Medical Officer; 2 FFARCS, Senior MedicalOfficer; 3MBBS, FANZCA, FHKCA, FHKAM(Anaesthesiology), Consultant and Cluster ChiefExceutive (Kowloon Central). Department ofAnaesthesia, Queen Elizabeth Hospital.Address correspondence to: Dr KC Lui, Departmentof Anaesthesia, Queen Elizabeth Hospital, 30Gascoigne Road, Kowloon, Hong Kong. E‐mail:luikc@hkstar.com76There are also increasing number of parturientswho wish to be awake during their operations.Choice of regional techniques includes spinalanesthesia, epidural anesthesia and combinedspinal epidural anesthesia (CSE). 1Spinal anesthesia has the advantages ofsimplicity of technique, requiring small doses oflocal anesthetic, producing faster onset, intenseand reliable block. However, the problems ofunanticipated extensive block, limited durationof anesthesia, hypotension and postduralpuncture headache cannot be ignored. Epiduralanesthesia can be extended to provide postoperativepain relief, but takes up more time

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005and involves a higher incidence of inadequateand superficial block.Combined spinal epidural anesthesia (CSE)was introduced by Brownridge in 1981. 2 It hasthe advantage of both epidural and spinalanesthesia and may reduce many of thedisadvantages. It may be a preferred choice forcesarean section. Different techniques for CSEhave also been described. 3‐5Previous study by Rawal et al showed thatsurgical analgesia and muscular relaxationfollowing CSE were superior to those seen afterepidural anesthesia for cesarean sections. 6Moreover, the incidence of hypotension waslower following CSE anesthesia as compared toepidural anesthesia. Thoren et al demonstratedthat spinal anesthesia and sequential CSEprovided good surgical analgesia and musclerelaxation for cesarean section with the sameincidence of hypotension. 7 As Thoren usedbupivacaine only for spinal anesthesia, it isuncertain whether the addition of fentanyl tobupivacaine will produce different analgesicefficacy and complications profile of CSE. Wecompared the quality of block between spinaland CSE anesthesia for cesarean delivery.Methods and MaterialsAfter obtaining approval from Local Ethicscommittee, 60 healthy (American Society ofAnesthesiologists Physical Status Class 1 or 2),full term parturients, scheduled for electivecesarean section were recruited for the study.All patients weighted 50 to 90 kg, had singlefetus and uncomplicated pregnancies. Informedwritten consent was obtained. Patients withbleeding tendency or receiving anticoagulants,and those with deformities of the spine orinfection around the injection site were excludedfrom the study. We also excluded patients withhistory of allergy to local anesthetics or fentanyl,and had major cardiorespiratory diseases, sepsisor uncontrolled diabetes mellitus..All patients received 0.3 M sodium citratesolution 30 ml orally 30 minutes beforeanesthesia. They were then randomized byrandom number allocation to two groups of 30patients (spinal and CSE group). Beforeanesthesia, 15 ml/kg of acetated Ringer solutionwere infused intravenously over a period of 15‐20 min. The solutions were pre‐warmed to 37°C.Baseline arterial pressure was measured whenthe patient lying supine with lateral tilt in theoperation table. The urinary bladder wascatheterized. Oxygen 4 L/min was administratedthrough a nasal catheter. All regional blockswere performed by the same anesthetist.Spinal groupPatients received spinal anesthesia in rightlateral position under aseptic technique. Afterinfiltrating the skin with 1.5% lignocaine, a 26GQuincke needle (Spinocan, B. Braun, Germany)was introduced by midline approach at L2/3interspace. The bevel was faced laterally to theleft. This was taken as the starting time ofregional block. A total of 2.2 ml 0.5% heavybupivacaine with 8% glucose (Astra, Australia)and fentanyl 10 μg (Janssen Pharmaceutica,Belgium) was injected intrathecally. The patientwas then placed in the supine position with aleft lateral tilt, and this signified the end ofregional block.CSE groupSimilarly, patients in the CSE groupreceived CSE block under aseptic technique inthe right lateral position. An 18G Tuohy needle(Espocan, B.Braun, Germany) was introduced atL2/3 level in the midline, with bevel facingcephalad. Epidural space was identified by lossof resistance to air. A 26G extra long Quinckeneedle was then inserted through the Tuohyneedle into the subarachnoid space. A total of1.5 ml 0.5% heavy bupivacaine with 8% glucoseand fentanyl 10 μg was injected intrathecally.The spinal needle was then withdrawn and theepidural catheter was inserted 4 cm into theepidural space. The patient was immediatelyturned to supine with a left lateral tilt.The spread of the sensory block was testedby response to pinprick bilaterally. Dermatomallevel was tested every min for the first 10 minand then every 5 min for the remaining 50 minafter resuming the supine posture. Operationwas allowed to start once the sensory blockadereacheds T6 level.In the CSE group, if the sensory level did77

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005not reach T6 after 10 minutes, additional 0.5 %plain bupivacaine (Astra, Australia) was injectedepidurally. This was achieved by an initial testdose of 2 ml 0.5% plain bupivacaine, andadditional 1.5 ml per unblocked segment wasinjected epidurally until T6 level was reachedwithin 20 minutes. 4During surgery, surgical analgesia wasgraded by the patients as excellent, good, fair orpoor. If patients complained of pain duringsurgery, increments of fentanyl 50 μg IVI wasgiven as required.Monitoring included automatic oscillometricdevice (Narkomed 4E, North America),electrocardiograph (Vitalert 2000, NorthAmerica) and pulse oximetry (Narkomed 4E,North America). After resumption of the supinewith lateral tilt position, maternal arterialpressure was measured at one minute intervalfor first 10 min and then at 5 minutes’ intervalfor 50 minutes thereafter. Hypotension wasdefined as a decrease in systolic arterial pressuremore than 20% of baseline or < 100 mmHg. Thiswas treated with boluses of ephedrine 5 mg IVIand rapid fluid infusion up to 10 ml/kg.Respiratory depression, defined as respiratoryrate less than 10 per minute or SaO2 < 90%, wastreated by increasing inspired oxygenconcentration and intravenous naloxone in 0.1mg boluses.Post‐operatively, sedation score, respiratoryrate, arterial pressure, pulse rate and oxygensaturation were monitored for three hours.Respiratory depression, pruritus, nausea andvomiting were recorded and treated accordingly.Indomethacin suppository 100 mg (Lifepharma,Italy) was given to the patients for pain reliefduring this period. Patients were followed upand the occurrence of post dural punctureheadache (PDPH) was recorded. Apgar scoresand umbilical blood gases sampling results werealso collected.Statistical AnalysisParametric data was analyzed using 2‐sample t test. Χ 2 test was used to compare theincidences of complications includinghypotension, nausea and vomiting, pruritus,shivering, PDPH, as well as inadequateanalgesia between the two groups. Apgar scoreswere analyzed by Mann Whitney test. Data werepresented as mean ± standard deviation.ResultsThe spinal and CSE groups were notdifferent in age, weight, height and gestation(Table 1). There were no differences betweengroups in the maximal analgesic level achievedas well as the analgesic level at 10 minutes aftercompletion of regional block. The volume ofintravenous fluid given was also similar.Patients in the spinal group achieved themaximal analgesic level in 5.8 ± 0.4 min, andwas significantly faster (P = 0.05) than CSE, 8.0 ±1.1 min.Times spent in performing the CSE wassignificantly longer than that required in spinalanesthesia (Table 1). The time interval from startof regional block to skin incision was alsosignificantly longer for CSE. The time intervalfrom uterine incision to delivery was similarbetween groups, whereas the time interval fromskin incision to delivery was longer in the spinalgroup.The incidence of hypotension was higher inthe spinal group (93%) than CSE group (73%)but the difference did not reach statisticalsignificance (P = 0.08). Lowest systolic arterialpressure developed faster in the spinal groupthan CSE group (P = 0.05, Table 2). Percentage ofmaximal drop of systolic blood pressure wasalso similar between groups. Patients in thespinal group required significantly moreephedrine (17.5 ± 1.8 mg) than those in CSEgroup (12.0 ± 1.6 mg, P = 0.03). In those patientswho needed ephedrine, the time to first dose ofephedrine was similar between groups.All patients in the spinal group hadadequate surgical anesthesia for the cesareansection. Two patients in the CSE groupdeveloped inadequate surgical anesthesia. Onepatient had analgesic level of T6 but reporteddiscomfort after delivery and requiredintravenous fentanyl. The other patient hadanalgesic level of T10 after 10 minutes and78

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Table 1. Patient characteristics and performance of regional block. Values are mean ± SD; Levels areexpressed as median (range)Spinal group(n = 30)CSE group(n = 30)P ValuesPatient characteristicsAge (year) 31.0 ± 0.9 32.8 ± 0.8 0.89Body height (cm) 155.4 ± 1.2 155.7 ± 1.5 0.91Body weight (kg) 65.8 ± 1.3 65.1 ± 1.5 0.96Maturity (weeks) 38.5 ± 0.2 38.4 ± 0.2 0.87Performance of regional blockMaximal dermatomal level [median (range)] T4 (T2‐5) T4 (T2‐6) 0.85Level at 10 min [median (range)] T4 (T2‐5) T4 (T2‐10) 0.99Time to maximal level after completion of block (min) 5.8 ± 0.4 8.0 ± 1.0 < 0.05Performance time (sec) 217.8 ± 23.1 336.5 ± 4.0 0.01Start of block to skin incision time (min) 10.3 ± 0.5 13.9 ± 1.2 0.01Start of block to delivery time (min) 20. 0 ± 0.7 22.2 ± 1.3 0.16Skin incision to delivery time (min) 9.7 ± 0.5 8.2 ± 0.5 0.05required an epidural top up.Incidence of complications was tabulated inTable 4. There were no statistically difference inthe occurrence of nausea, vomiting, pruritus andshivering between groups. No patients in thespinal group but three in the CSE groupdeveloped PDPH. One required epidural bloodpatch. There was no evidence of accidental duralpuncture by 18G Tuohy needle in all threepatients. The first patient had cesarean sectionfor breech presentation. She developed severePDPH on day 1 after delivery. She refused bloodpatch and was treated conservatively. Herheadache subsided five days afterwards. Thesecond patient had cesarean section formacrosomia. She developed PDPH on day 1. Shereceived epidural blood patch on Day 2.Headache completely resolved afterwards. Thethird patient received cesarean section fortransverse lie. She developed PDPH on day 2.She requested conservative treatment and theheadache resolved on day 5. No furtherheadache was reported in these patients afterdischarged from hospital.There was no difference in Apgar scores in 1and 5 minutes between the 2 groups (Table 2).None of the neonates had Apgar score below 7.The results of fetal blood gas were similar inboth groups. Patient assessment of anesthesiawas also similar in both groups (Table 3).DiscussionCSE combines the advantages of epiduraland spinal anesthesia. It provides a more intenseblock that is reliable and faster than epiduralanesthesia. CSE is more flexible because itprovides a means for extension of the blockthrough the epidural route. Hence smaller dosesof local anesthetic can be administeredintrathecally. This may reduce the incidence andseverity of hypotension. CSE can also beextended to provide postoperative pain relief.Hypotension is one of the major hazards ofregional anesthesia for cesarean section. Severehypotension induces maternal or neonatalmorbidity. 8 Prophylactic measures againsthypotension included fluid preloading,maternal positioning to minimize aortocavalcompression and vasopressors like ephedrine.Hypotension may also be reduced by usingsmaller intrathecal dose of local anesthetics. Thesubarachnoid doses of hyperbaric bupivacainefor cesarean section had been reviewedpreviously. 9,10 Various bodily parameters werefound to correlate with anesthetic dose for79

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Table 2. Complications and neonatal outcomes after spinal or combined spinal and epidural block.Values expressed as mean ± SD.Spinal group CSE group(n = 30) (n = 30)P ValuesHypotension (number, %) 28 (93%) 22 (73%) 0.08Percentage of maximal decrease in systolic pressure 30.4 ± 1.6 26.8 ± 1.9 0.l5Time to develop the lowest SBP (min) 4.5 ± 0.8 9.3 ± 2.3 0.05Dose of ephedrine consumed (mg) 17.5 ± 1.8 12.0 ± 1.7 0.03Time to first dose of ephedrine (min) 2.8 ± 0.4 3.1 ± 0.3 0.52Nausea and vomiting (number) 10 10 1.00Pruritus (number) 1 0 0.50Shivering (number) 2 2 1.00Postdural puncture headache (number) 0 3 0.12Apgar scoreat 1 min [median (range)] 8 (7‐9) 8 (7‐9) 0.44at 5 min [median (range)] 9(8 ‐ 10) 9(8 ‐ 9) 0.72Cord blood analysispH 7.31 ± 0.01 7.32 ± 0.01 0.38Carbon dioxide tension (kPa) 5.6 ± 0.2 5.8 ± 0.1 0.49Oxygen tension(kPa) 3.5 ± 0.2 3.5 ± 0.2 0.86Bicarbonate concentration (mmol/L) 21.2 ± 0.6 21.3 ± 0.5 0.18Base excess (mmol/L) ‐4.7 ± 0.6 ‐3.6 ± 0.4 0.15spinal anesthesia. Patient height is mostcommonly taken into account when determiningthe dose of spinal anesthesia. 11 Recent studiesshowed that the vertebral column length was animportant factor in dose selection. 12,13Satisfactory block has been reported withsmaller doses of hyperbaric bupivacaine rangingfrom 7.5 to 12.5 mg. This was associated with 33% hypotension. 6CSE allows the use of smaller dose of localanesthetics for the spinal component as theepidural catheter can be used to supplementinadequate block if necessary. It is stillcontroversial whether CSE is associated withless hypotension than spinal or epiduralanesthesia. Earlier study by Rawal et al showeda lower incidence of hypotension in CSEcompared with epidural anesthesia for cesareansection. 6 In this study, the incidence ofhypotension is high with respect to the doseadministered, 73 % of patients in CSE groupversus 93 % of patients in spinal groupdeveloped hypotension.Fentanyl has bupivacaine sparing effect andmay reduce the incidence of hypotension. 14,15Fentanyl has been added to the subarachnoidbupivacaine to enhance surgical analgesia andprolong the duration of anesthetic block. 16‐18Fentanyl produced many of its clinical effectsvery early after intrathecal administration in theintraoperative periods. Earlier study by Sergio etal (17) showed that the combination ofbupivacaine and a low dose of fentanyl (0.25Table 3. Patient assessment of surgical anesthesia.Data were number of patients (%).Spinal group CSE group(n=30)(n=30)Excellent 10 (33.3%) 11 (36.6%)Good 20 (66.6%) 18 (60%)Fair 0 1 (3.3%)Poor 0 080

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005μg/kg) provided excellent surgical anesthesia.Adverse effects were minimal but postoperativeanalgesia was short lasting. Thus the addition offentanyl to subarachnoid bupivacaine mayreduce bupivacaine requirement. This in turnreduces the incidence of hypotension. In ourstudy, patients in the CSE group receivedhyperbaric bupivacaine 7.5 mg and fentanyl 10μg intrathecally. Twenty‐eight patients (93 %)reported satisfactory surgical analgesia with thiscombination alone and only two patients hadinadequate block. Our study would suggest thatthe dose regime is sufficient to provide surgicalanesthesia for most patients.The incidence of PDPH in CSE group rangesfrom 0.3‐2.5%. 6,19,20 It is difficult to compare theincidence of PDPH across different studiesbecause of the varying techniques and needlesused. 3‐5 Several workers commented on the verylow incidence or lack of PDPH after CSEanesthesia. Dennison reported only two PDPHout of 400 patients who received CSE forcesarean section, 21 while Kumar reported 2 casesof mild headache in 300 cesarean deliverypatients. 22 However, Collis et al reported highincidences of PDPH (2.3 %) in CSE technique in300 mothers using single‐space needle‐throughneedletechnique with 16 gauge Tuohy and 27gauge extralong spinal needles. 19 For CSE usedfor labour pain relief, Norris et al suggested thatit might not be associated with an excessiveincidence of PDPH. 20 The incidence and severityof PDPH is closely associated with the size ofneedle puncture, character of the needle tip andexperience of the performers. In our study, wehad no report of PDPH in the spinal group butthree patients in the CSE group developedPDPH. All of them received single space, needlethrough needle, CSE anesthesia with EspocanCSE set (18G Tuohy needle with 26G Quinckespinal needle). The reason of this unexpectedhigh incidence of PDPH was not clear. It mightbe due to catheter puncture of the dura orinadvertent shift of the Tuohy needle duringinjection for spinal anesthesia. There was noevidence of CSF leak either from needle orcatheter at any stage. It could also occur bychance because of the small sample size.Some authors have commented thatcombined spinal epidural anesthesia appearedcumbersome and the use of smaller dose of localanesthetic intrathecally in CSE will delay in theestablishment of satisfactory analgesic level. 23Our study confirmed that it took longer time toperform CSE. Majority of spinal anesthesiacould be performed within 2‐5 minutes, whereasCSE will require 3‐7 minutes. However, thedifference would be small when the start ofregional block to delivery time was considered.There was no difference in neonatal outcomesbetween groups despite the longer performancetime of CSE. It suggested that CSE anesthesiacan be performed within a reasonable timeinterval by experienced anesthesiologists and itproduces similar neonatal outcomes as spinalanesthesia. Therefore, CSE can be considered asa choice of anesthetic technique for emergencycesarean sections.ConclusionCSE anesthesia provided comparablesurgical anesthesia in cesarean section as spinalanesthesia. It was associated with less severematernal hypotension. The dose of heavybupivacaine could be reduced to 7.5 mg whenfentanyl is being used together. Both spinal andCSE anesthesia were associated with goodneonatal outcome.References1. Carrie LES. Extradural, spinal or combinedblock for obstetric surgical anaesthesia. Br JAnaesth 1990;65:225‐33.2, Brownridge P. Epidural and subarachnoidanalgesia for elective cesarean section.Anaesthesia 1981;36:70.3. Joshi GP, McCarroll SM. Evaluation ofcombined spinal‐epidural anesthesia usingtwo different techniques. Reg Anesth1994;19:169‐74.4. Feisby S, Juelsgaard P. Combined spinal andepidural anesthesia. Anesth Analg1995;80:821‐6.5. Rawal N, Van Zundert A, Crowhurst JA.Combined spinal epidural technique. RegAnesth 1997;22:406‐23.6. Rawal N, Schollin J, Wesstrom O. Epidural81

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005versus combined spinal epidural block forcesarean section. Acta Anaesthesiol Scand1988;32:61‐6.7. Titti T, Holmstrom B, Rawal N, et al.Sequential combined spinal epidural blockversus spinal block for cesarean section:effects on maternal hypotension andneurobehavioral function of the newborn.Anesth Analg 1994;78:1087‐92.8. Robson SC, Boys RJ, Rodeck C, Morgan B.Maternal and fetal haemodynamic effects ofspinal and extradural anaesthesia for electivecesarean section. Br J Anaesth 1992;68:54‐9.9. Finucane BT. Spinal anesthesia for cesareandelivery: the dosage dilemma. Reg Anesth1995;20:87‐9.10. De Simone CA, Leighton BL, Norris MC.Spinal anesthesia for cesarean delivery: acomparison of two doses of hyperbaricbupivacaine. Reg Anaesth 1995;20:90‐4.11. Shnider SM, Levinson G. Anesthesia forcesarean section, Anesthesia for Obstetrics.1987;p163.12. Hartwell BL, Aglio LS, Hauch MA, DattaSanjay. Vertebral column length and spreadof hyperbaric subarachnoid bupivacaine interm parturient. Reg Anesth 1991;16:17‐9.13. Hufihagle SL, Norris MC, Leighton BL, et al.Do patient variables influence thesubarachnoid spread of hyperbaric lidocainein the postpartum patient? Reg Anesth1994;19:330‐4.14. Lyons G, Columb. M, Hawthorne. L, Dresner.M. Extradural pain relief in labour:bupivacaine sparing by extradural fentanylis dose dependent. Br J Anaesth 1997;78:493‐7.15. Ben DB, Solomon E, Levin H, Admoni H,Goldik Z. Intrathecal fentanyl with smalldose dilute bupivacaine: better anesthesiawithout prolonging recovery. Anesth Analg1997;85:560‐5.16. Ready LB. Intraspinal opioid analgesia in theperioperative period. Anesthesiol Clin NorthAm 1992;10:145‐7.17. Sergio D. Belzarena. Clinical effects ofintrathecally administered fentanyl inpatients undergoing cesarean section.Anesth Analg 1992;74:653‐7.18. Dahlgren O, Huitstrand C, Jakobsson J, et al.Intrathecal sufentanil, fentanyl, or placeboadded to bupivacaine for cesarean section.Anesth Analg 1997; 85:1288‐93.19. Collis RE, Baxandall ML, Srikantharajah ID,et al. Combined spinal epidural analgesia:technique, management and outcome of 300mothers. Int J Obstet Anaesth 1994;3:75‐81.20. Norris MC, Grieco WM, Borkowski M, et al.Complication of labor analgesia: epiduralversus combined spinal epidural techniques.Anesth Analg 1994;79:529‐37.21. Dennison B. Combined subarachnoid andepidural block for cesarean section. CanAnaesth Soc J 1987;34:105‐6.22. Kumar C. Combined subarachnoid andepidural block for cesarean section. Can JAnesth 1987;34:329‐30.23. Reisner LS, Lin D. Anaesthesia for CesareanSection. In Chestnut DH, eds. ObstetricAnesthesia: Principles and Practice. St. Louis:Mosby, 1994:pp459‐498.82

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Low‐dose Subcutaneous Ketamine Infusion: a Dose FindingStudy for Post‐operative Analgesia1Derek LS Chan, 2 Tommy KL Suen, 3 Anne KwanDepartment of Anaesthesia, United Christian Hospital, Hong KongSUMMARYIn this double‐blinded, randomized controlled trial we determined the optimal dose of subcutaneousketamine infusion required for post‐operative analgesia after major abdominal surgery. Patients wererandomly allocated to receive either 0.9% saline or one of three ketamine doses (0.05, 0.1, 0.2 mg/kg/h),given as subcutaneous infusion. All patients were given intravenous morphine for postoperativeanalgesia using the patient‐controlled analgesia pump. A total of 50 patients completed the study. Fivepatients (one had ketamine 0.05 mg/kg/h; 2 received 0.1 mg/kg/h and 2 had 0.2 mg/kg/h) developedsevere psychomimetic adverse reactions that significantly compromised their safety. Postoperatively,there were no differences among groups in subjective assessment of analgesic efficacy, pain scores at restand on movement, opioid consumption and other adverse reactions. We observed a trend of lower PCAmorphine consumption among the ketamine groups. We concluded that the use of low‐dosesubcutaneous ketamine infusion for post‐operative analgesia is not recommended until furtherinformation regarding side effects profile is available.Keywords: Ketamine, Patient controlled analgesia, Anesthesia, Dose finding studyBull HK Coll Anaesthesiol 2005;14:83‐9Ketamine is a well know anesthetic agentfor over three decades. It has analgesicproperties at sub‐anesthetic doses. 4‐12,14,16This is related to a non‐competitive antagonism1MBBS, BSc(Med), FANZCA, FHKCA, FHKAM(Anaesthesiology), Associate Consultant; 2 MBBS,FANZCA, FHKCA, FHKAM (Anaesthesiology),Senior Medical Officer; 3MB BS, FANZCA,FHKCA, Dip Pal Med, Dip Pain Mgt (HKCA)FHKAM (Anaesthesiology), Dip Epi & Biostat, DipAcup, M Pal Care, Consultant and Chief of Service.Department of Anaesthesia, United Christian Hospital.Address correspondence to: Dr Derek Chan,Department of Anaesthesiology and OperatingServices, Alice Ho Miu Ling Nethersole Hospital, TaiPo, NT. E‐mail: dlschan@yahoo.com.hk83at the N‐methyl‐D‐aspartate (NMDA) receptorat the level of spinal cord dorsal horn. 1‐3 NMDAreceptors have an important role in thedevelopment of wind‐up phenomenon andlong‐term central sensitization of the painpathway. 2The use of sub‐anesthetic, low doseketamine as an analgesic has been investigated.Several reports have produced positive results,without the occurrence of dose‐dependentpsychomimetic side effects. 4,5,17,18 Effects oncardiovascular and respiratory systems are alsominimal at this range of doses. 4,5,7,10,12,17,18 Thereported analgesic efficacy is comparable to thatof morphine and pethidine without the commonside effects such as respiratory depression, 5,8,11,12

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005urinary retention, sedation, pruritus andtolerance. 4,13 The incidence of nausea andvomiting is less than or equal to that ofopioids. 4,13 When used as an adjunct, ketaminehas an opioid‐sparing effect. 4 A ketaminesubcutaneous infusion of 0.1 mg/kg/h has beenshown to produce similar analgesic efficacy as amorphine infusion of 0.03 mg/kg/h subcutaneously.5 In this regard, adequate analgesiawith fewer side effects will result in quickerrecovery and fewer complications. Thus, in thelong run, ketamine administration shouldreduce costs and potentially opioid tolerance,dependence, and chronic pain syndrome.Various routes of administration, includingsubcutaneous, have been examined and areeffective in providing analgesia. However, theoptimal dose range of subcutaneous ketamineinfusion for analgesia has not been found.Subcutaneous infusion is simple to administerand does not require an intravenous access. Thisstudy aims to provide clinicians withinformation on a useful alternative or adjuvantto postoperative analgesia.MethodsAfter obtaining hospital ethics committeeapproval, patients admitted for electiveabdominal surgery involving a midline incisionwere invited to participate if they had chosen IVpatient controlled analgesia (PCA) for postoperativepain relief. With written, informedconsent, 50 patients were randomly allocatedinto four groups receiving either 0.9% saline(Group S) or one of three ketamine doses (0.05,0.1 and 0.2 mg/kg/h, Group Ket 0.05, Ket 0.1,and Ket 0.2, respectively) given as asubcutaneous infusion. All patients wereprovided with PCA morphine. The pumps wereprogrammed to deliver morphine 1 mg bolus,lockout interval of 8 min and 4 hourly limit of0.25 mg/kg. Premedication was not prescribed.General anesthesia consisted of induction withthiopentone, maintenance with isoflurane in70% nitrous oxide/oxygen mixture. Trachealintubation and intra‐operative paralysis werefacilitated by either atracurium, cisatracurium orrocuronium. We gave morphine and/or fentanylfor intraoperative analgesia. The actual conduct84of anesthesia was left to the discretion of theattending anesthetists. A subcutaneous bolus ofketamine (0.2 mg/kg) was given immediatelyprior to the infusion while patients in the groupS received equivalent volume of 0.9% normalsaline. The infusion was commencedimmediately after induction of generalanesthesia prior to surgical incision. The anteriorchest wall was used as the infusion site becauseit caused minimal interference with the surgeryand provided easy access for inspection andreposition during study period. The infusionwas given via a 25G subcutaneous infuserneedle of known volume, and the syringe drivenby a syringe pump (Terumo Corporation, Tokyo,Japan). List anesthetists, recovery room nurses,ward staffs, and patient assessors were blindedto the treatment used.Data collection was started at induction ofgeneral anesthesia and lasted for 72 hours aftercommencement of PCA use. Ketamine wasinfused for the first 48 hours. Ward nursesexperienced in looking after continuousinfusions and PCA pumps monitored thepatients. Patients suffering from nausea andvomiting were treated with metoclopramide 10mg IVI, as requested and those showingpsychomimetic symptoms were treated withdiazepam 2 mg IVI every 8 hours, as indicated.Patient demographic data were recorded.Intraoperative data included type and durationof surgery, length and dermatomal range ofincision, and total opioid dose. Recovery dataincluded length of hospital stay, total opioiddose. Pain scores were recorded using a 11‐pointverbal rating scale (VRS: 0 = no pain, 10 = worstpain imaginable) at rest and on movement.Postoperatively, 2 hourly nursing observationsincluding pain scores, sedation scores (0 = alert,4 = unarousable), presence of nausea, vomiting,PCA consumption, volume of study druginfused, heart rate, arterial pressure, respiratoryrate, and pulse oximetry reading. The acute painservice also assessed the patients twice daily forthe presence of hallucination, vivid dreams, andother psychomimetic side effects such asparanoia and delusion. At the end of the 48‐hourinfusion, patient were asked to give asatisfactory score of the effectiveness of

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Table 1. Patient demographics and operative data. Data presented as mean (SD), or number (n).Group S Ket 0.05 Ket 0.1 Ket 0.2Number of patients 12 10 15 13Age (year) 61 ± 9 67 ± 13 66 ± 12 62 ± 11Sex, M/F (n) 9 / 3 6 / 4 9 / 6 8 / 5Weight (kg) 53 ± 6 48 ± 12 54 ± 11 53 ± 11ASA Status (n)I 0 0 0 3II 12 10 15 10Type of surgery (n)Upper gastrointestinal 6 6 7 6Colorectal 6 3 8 6Gynecological 0 1 0 1Length of incision (cm) 21 ± 3.5 19 ± 3.3 19 ± 1.9 19 ± 2.3Intraoperative morphine doses (mg) 13.5 ± 4.8 10 ± 3.3 11.5 ± 3.3 12.5 ± 4.3Recovery room morphine doses (mg) 9 ± 8.6 9 ± 4 7 ± 5.8 6.5 ± 7.9Duration of surgery (min) 258 ± 80 221 ± 82 255 ± 65 254 ± 44Duration of recovery stay (min) 96 ± 36 78 ± 22 75 ± 30 69 ± 29analgesia that they had received (1 = poor, 5 =excellent).Outcome measures were compared usingthe general linear model. Complicationfrequencies were compared using χ 2 test.ResultsA total of 50 patients received the allocatedstudy medication according to protocol. Patientcharacteristics were comparable among groups(Table 1). Fifteen patients developed psychomimeticreactions (Table 2). All had vividdreams, nine out of 15 also had hallucinations(visual and/or auditory). Five of these 9 patientsdeveloped severe psychomimetic adversereactions (1 in group Ket 0.05; 2 in group Ket 0.1;2 in group Ket 0.2). They presented withparanoid delusions, disturbing visual and/orauditory hallucinations, acute agitation anddelirium. Symptoms were severe enough towarrant physical restraints, treatment withdiazepam and subsequent stopping of studydrug infusion. These adverse reactions causedsignificant compromise to the patients’ safetyand postoperative management. All 5 patientsdeveloped acute delirium during the last 12hours of study drug infusion. They sufferedfrom severe agitation, four of them pulled outthe surgical drains, all pulled out intravenouscatheters repeatedly, three required physicalrestraints and 1 attempted to leave the wardwithout success. Moreover, three patientsdeveloped paranoid delusions (2 in Ket 0.2group, 1 in Ket 0.1 group) requiring treatmentwith diazepam. All 5 patients wereasymptomatic 24 hours after stopping of studydrug infusion. On subsequent interview, all hadonly partial recollection of the events and detailsof the hallucinations. Four claimed theexperience to be stressful and frightful.However, all 5 patients reported good analgesiaduring the study period.Most of the 50 recruited patients rated theiranalgesia as good (Table 2). There were nodifferences between the groups with respect tosubjective assessment of analgesic efficacy, painscores at rest (Figure 1) and on movement(Figure 2), opioid consumption and adversereactions. We also observed a trend of smallermorphine consumption among the ketaminegroups.DiscussionIn this study, we were unable to determinethe optimal dose of subcutaneous ketamine foranalgesia in patient recovering from major85

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Figure 1. Pain scores [verbal rating scale (0 = no pain, 10 = worst pain imaginable)] at rest and duringcoughs after surgery.abdominal surgery. We encountered severepsychomimetic sided effects and yet were notable to reproduce the analgesic effectdemonstrated by previous studies. Neverthelessthere was a trend towards lower PCA morphineconsumption among patients in the ketaminegroups (Table 2).In a recent review, the incidence ofpsychomimetic effects varied from 5% to greaterthan 30% after high dose ketamine anesthesia. 15Several factors were found to be associated withpsychomimetic effects. These include advancedage, subjects who normally dream or have ahistory of psychopathology, high doses ofketamine (> 2 mg/kg) and rapid intravenousadministration (> 40 mg/min). Apart fromTable 2. Postoperative outcomes and incidence of adverse reactions. Data are presented as numbers (%) andmean ± standard deviation.Group S Ket 0.05 Ket 0.1 Ket 0.2 P ValuesNumber of patients 12 10 15 13Satisfactory score of analgesia at 48 h 4 (3‐5) 4 (2‐5) 4 (1‐5) 4 (2‐5) 0.87(1=poor, 5=excellent)PCA Morphine use (mg/24 h)0‐24 h 32 ± 17 25 ± 17 27 ± 13 29 ± 28 0.7624‐48 h 25 ± 22 16 ± 19 17 ± 10 17 ± 17 0.6148‐72 h 19 ± 16 14 ± 16 14 ± 13 15 ± 15 0.73Total used (mg) 76 ± 21 55 ± 18 58 ± 17 61 ± 22 0.87Average sedation score over 48 h1 (1‐3) 1 (1‐3) 1(1‐3) 1(1‐3) 0.92(1=alert, 4=unarousable)Adverse EventsNausea 6 (50%) 4 (40%) 7 (47%) 5 (38.5%) 0.86Vomiting 4 (33.3%) 3 (30%) 4 (26.7%) 3 (23.1%) 0.91Dizziness 8 (66.7%) 5 (50%) 10 (66.7%) 11 (84.6%) 0.37Hallucination 2 (16.7%) 1 (10%) 3 (20%) 3 (23.1%) 0.87Vivid dreams 4 (33.3%) 3 (30%) 3 (20%) 5 (38.5%) 0.75Paranoid delusions 0 (0%) 0 (0%) 2 (13.3%) 1 (7.7%) 0.41Acute confusion 1 (8.3%) 0 (0%) 2 (13.3%) 2 (15.4%) 0.6386

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005ConclusionIn summary, we observed severepsychomimetic adverse reactions aftersubcutaneous ketamine infusion. We do notrecommend the use of ketamine forpostoperative pain relief until more informationon side effect profile of such regime is available.AcknowledgementWe wish to thank Dr Adam Tucker (email:research@southernhealth.org.au) for histhoughtful suggestion.References1. Willets J, Balster RL, Leander JD. Thebehavioral pharmacology of NMDAreceptor antagonists. Trends Pharmacol Sci1990;11:423‐28.2. Ilkjaer S,Petersen KL, Brennum J, et al. Effectof systemic NMDA receptor antagonist(ketamine) on primary and secondaryhyperanalgesia in humans. Br J Anaesth1996;76:829‐34.3. Dickenson AH. Spinal cord pharmacologyof pain.Br. J. Aneasth. 1995;75:193‐200.4. Schmid RL, Sandler AN, Katz J. Use andefficacy of low‐dose ketamine in themanagement of acute postoperative pain: areview of current techniques and outcomes.Pain 1999;82:111‐25.5. Bhattacharya A, Gurnani A, Sharma PK,Sethi AK. Subcutaneous infusion ofketamine and morphine for relief ofpostoperative pain: a double blindcomparative study. Ann Acad MedSingapore 1994;23:456‐9.6. L, Sinclair DD, Van Hasselt CH. Intravenousketamine for postoperative analgesia. S AfrMed J 1975;49:1437‐40.7. Dich‐Nielsen JO, Svendsen LB, Berthelsen P.Intramuscular low‐dose ketamine versuspethidine for postoperative pain treatmentafter thoracic surgery. Acta AnaesthesiolScand 1993;6:861‐5.8. Jhangir SM, Islam F, Aziz L. Ketamineinfusion for postoperative analgesia inasthmatics: a comparison with intermittentmeperidine. Anesth Analg 1993;76:45‐9.9. Javery KB, Ussery TW, Steger HG,Colclough GW. Comparison of morphineand morphine with ketamine forpostoperative analgesia. Can J Anesth1996;43:212‐5.10. Joachimsson PO, Hedstrand U, Eklund A.Low‐dose ketamine infusion for analgesiaduring postoperative ventilator treatment.Acta Anaesthesiol Scand 1986;30:697‐702.11. Maurset A, Skoglund LA, Hustveit O, Oye I.Comparison of ketamine and pethidine inexperimental and postoperative pain. Pain1989;36:37‐41.12. Owen H, Reekie RM, Clements JA, WatsonR, Nimmo WS. Analgesia from morphineand ketamine. A comparison of infusion ofmorphine and ketamine for postoperativeanalgesia. Anaesthesia 1987;42:1051‐6.13. Sethna NF, Liu M, Gracely R, Bennett GJ,Max MB. Analgesic and cognitive effects ofintravenous ketamine‐alfentanil combinationversus either drug alone afterintradermal capsaicin in normal subjects.Anesth Analg 1998;86:1250‐6.14. Stubhaug A, Breivik H, Eide PK, Kreunen M,Foss A. Mapping of punctuatehyperhyalgesia around a surgical incisiondemonstrates that ketamine is a powerfulsuppressor of central sensitization to painfollowing surgery. Acta Anaesthesiol Scand1997;41:1124‐32.15. White PF, Way WL, Trevor AJ.Pharmacology of ketamine ‐ its pharmacologyand its therapeutic uses. Anesthesiology1982;56:119‐36.16. Wilder‐Smith OH, Arentdt‐Nielsen L,Gaumann D, Tassonyi E, Rifat KR. Sensorychanges and pain after abdominalhysterectomy; a comparison of anaesthethicsupplementation with fentanyl versusmagnesium or ketamine. Anesth Analg1998;86:95‐101.17. Krystal JH, Karper LP, Seibyl JP, et al.Subanaesthetic effects of the noncompetitiveNMDA antagonist, ketamine, in humans.Psychotomimetic, perceptual, cognitive and88

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005neuroendocrine responses. Arch GenPsychiat1994;51:199‐214.18. Krystal JH, Karper LP, Bennett A, et al.Interactive effects of subanaestheticketamine and subhypnotic lorazepam inhumans. Psychopharmacology 1998;135:213‐29.19. Reeves M, Myles PS, Lindholm D. Addingketamine to morphine for patient‐controlledanalgesia after major abdominal surgery: adouble‐blinded randomized controlled trial.Anesth Analg 2001;93:116‐20.20. Bowdle TA, Radant AD, Cowley DS, et al.Psychedelic effects of ketamine in healthyvolunteers. Anesthesiology 1998;88:121. Parikh SS, Chung F. Postoperative deliriumin the elderly. Anesth Analg 1995;80:1223‐32.22. Seymour G. Acute and chronic confusionalstates in the elderly surgical patient. In:Medical assessment of the elderly surgicalpatient. Kent, England: Croom Helm,1986:229‐39.23. Lipowski ZJ. Delirium (acute confusionalstates). JAMA 1987;258:1789‐92..24. Eide K, Stubhaug A, Oye I, Breivik H.Continuous subcutaneous administration ofthe NMDA receptor antagonist ketamine inthe treatment of post‐herpetic neuralgia.Pain 1995;61:221‐8.89

Perioperative NursingBull HK Coll Anaesthesiol Volume 14, Number 2 July 2005An audit of Perioperative Hypothermia in the Elderly Patients1Man Shan Ma, 2 Alick HF ChiuDepartment of Anaesthesiology, Operating Theatre and Sterile Supply, North District Hospital, Hong KongSUMMARYWe conducted an audit of temperature management in the perioperative period. Core temperature wasrecorded in the elderly patients using a tympanic thermometer during reception to the theater suite, 1and 3 hours after of surgery and upon admission to and discharge from the recovery room. We foundthat the use of force air warming device with hospital blanket reduce the incidence of hypothermia from7% to less than 1%. There was no evidence of thermal injury. We concluded that force air warming withhospital blanket is an effective, efficient way to maintain perioperative normothermia.Keywords: Geriatric; anesthesia, hypothermia, perioperative phase, force air warmingBull HK Coll Anaesthesiol 2005;14:90‐4Hypothermia is defined as coretemperature less than 36°C. 1‐6Inadvertent hypothermia is associatedwith a number of serious consequences. 6‐8Patient experienced hypothermia have increasedincidence of wound bleeding and infection,decreased cardiac function, delayed recoveryfrom anesthesia and a longer stay in theoperating room. 7,8 In March, 2000, we found that7% of all patients undergoing elective surgeryhad hypothermia during their stay in theoperating room. In this survey, we noted thatelderly patient are especially vulnerable becausethey have less subcutaneous fat, decreasedmetabolic rate and impaired cold sensation.In the literature, a number of interventionsare shown to be effective in preventinghypothermia. Warmed intravenous fluid, cottonblanket and heated airway humidification weretechniques that are commonly applied in ourhospital. 9‐15 In this audit, we evaluated the use offorced air warming to prevent perioperativehypothermia in elderly patients scheduled forgeneral surgical procedures. The objective of theprogram was to limit the occurrence ofperioperative hypothermia to less than 7%among our target group of patients.Methods and Materials1RN, BN, Registered Nurse; 2RN, DepartmentOperation Manager. Department of Anaesthesiology,Operating Theatre and Sterile Supply, North DistrictHospital, Hong KongAddress correspondence to: MS Ma, DepartmentAnaesthesiology, Operating Theatre and SterileSupply, North District Hospital, 9 Po Kin Road,Sheung Shui, NT. E‐mail: mams323@yahoo.com.hkThe study was performed in the operatingtheatre of the North District Hospital. Theperioperative nursing team got together andformulated an action plan.Target patient group selectionThe team recognized patients more than 60years, of either gender, undergoing elective90

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005surgery with general, spinal or combinedgeneral and regional anesthesia are at risk ofinadvertent hypothermia.We have developed a standard protocolwith the use of warmed intravenous fluid,cotton blanket and heated airwayhumidification according to the temperature ofpatient. We use the tympanic thermometer as atool to monitor patient temperature. 16 Fivereadings during the perioperative period wererecorded. The first reading was taken on arrivalto the theater holding areas. The second andthird readings were measured intraoperativelyat 1 and 3 hours after skin incision, respectively.The fourth and fifth readings were measuredduring admission to and discharge from therecovery bay, respectively.Standard protocol for the prevention of hypothermiain elderly patients(1) In the holding area body temperature wasrecorded. The room temperature wasmaintained at 21°C.(2) After the patient was transferred to the table,patient was covered with warmed blankets.Body exposure was minimized whenapplying physiologic monitors.(3) During the operation, a force air warmingdevice (Bair Hugger Model 500 WarmingUnit, Augustine Medical, Eden Prairie, MN)was applied. The area to be warmed wascovered with one hospital blanket. Theedges were tucked around the operatingroom (Figure 1). Extremities were entirelycovered with warm towel or blanket. Warmintravenous fluid was also used. Ifhypothermia (< 35°C) was detected duringsurgery, we used blood warming devicewith warming coil to administrateintravenous fluid. Another forced airwarming device was used at the bed endand the theatre room temperature wasadjusted to 24°C(4) Postoperatively, the patient body wasimmediately covered after surgery wascompleted. The skin was clean with warmcotton pad and was dried it up at once.This audit was conducted for two consecutivemonths. The study was approved by thehospital theater management committee andethics review board. Informed consents wereobtained from all patients.Differences in temperature over the varioustime points were tested by analysis of variancewith repeated measures. We also analyzed theeffect of anesthesia and age on perioperativetemperature.Figure 1. Forced air warming technique using thehose of a Bair Hugger Model 505 Warming UnitThe area to be warmed was covered with onehospital blanket. Care was taken not to direct theair stream toward the patient. A second hospitalblanket was placed over the first.ResultsA total of 361 patients were recruited for thestudy. The mean core temperature is sown inFigure 2. There were only 2 patients withtemperature < 36 o C. They recorded duringreception in the theater holding area (Figure 2).Our data suggested that the force air warmingdevice using hospital blanket is effective inpreventing hypothermia. There were nocorrelation between age or anesthetic type andperioperative temperature (Figure 3).Upon discharge from the recovery room, nopatient had evidence of redness, swelling, orblisters (as signs of thermal injury).91

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005DiscussionThe result of our audit suggested that a standardwarming protocol was effective, safe andefficient in preventing perioperativehypothermia among elderly patients. Thenumber of patients with hypothermia wasreduced from 7% to less than 1%. The protocolensured no wasting of resource in patientwithout need because warming device wasapplied according to patent’s condition. Thisprotocol also protected patient from thecomplication of hypothermia and reduce theiranxiety by providing warmth.In the present study, we used the forced airwarming device with hospital blanket. Airtemperature was set as 38˚C. Kabbara et alcompared the use of forced air warming withhospital blanket with commercial blanket andfound that both are effective in maintainingnormothermia and no thermal injuries wasreported. Given the cost of commercial blanket;we recommended that hospital blanket can beused as an alternative. 17Figure 2. Changes of core temperature overtime. Time points are: 0=preoperative holding area,1= one hour after surgery, 2=3 hours after surgery, 3and 4=admission and discharge from recovery room,respectively.Misuse of warming device, however cancause complications including burns. Accordingto the manufacturer, airflow of the forced airwarming unit should not be directed to thepatient’s skin surface. The risk of thermalinjuries is higher if the warming unit is set >43˚C.Figure 3. Changes of temperatureover time in different agegroups.Time points are:0 = preoperative holding area,1 = one hour after surgery,2 = 3 hours after surgery,3 and 4 = admission and dischargefrom recovery room, respectively.92

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Rapid increase in body temperature mayalso induce vasodilation leading to adversehaemodynamic effect. 18 Healthcare professionalsshould familiarize themselves with the correctinstruction of the forced air warming unit.Standardized the temperature setting and theuse of the unit can improve patient safety andclinical outcome. Caution should be takenthroughout the perioperative period in thesetting of the force air warming unit. The idealsetting should be medium (around 38˚C) andnurses should check for any accidental changesof the setting, alarming of overheating, orunintended dislodgement of the hose from thecotton blanket. During the implementation ofthe protocol, we found that application of forceair warming unit can cause discomfort to patient.For patient under regional anesthesia, nursesshould ask patient for their feeling on anyoverheating or discomfort during operation.Our audit revealed that most of the nursingstaff are cooperative and are capable toimplement the protocol with care. One of themain reasons for the success of the program isthe team spirit of our staff. It was also reflectedthat all the health care workers were very alertin keeping patient warm in the operatingtheatre. 19 We believe nursing staffs areaccountable for the prevention of perioperativehypothermia and should therefore share theheavy workload of the busy anesthetists inproviding high quality clinical service.ConclusionIn this study we concluded that force airwarming with hospital blanket is an effective,efficient way to maintain perioperativenormothermia.Reference:1. Ensminger J, Moss R. Preventinginadvertent hypothermia ‐ a success storyAORN 1999;70:298‐301.2. Touzeau FP. The big chill: inadvertenthypothermia. ACORN Journal 1994;7:26‐8.3. Readby L. Hypothermia: the cold facts ofsurgery. Aust J Adv Nursing 1986;4:19‐24.4. Wehmer MA, Baldwin BJ. Inadvertenthypothermia: Clinical nursing research.AORN Journal 1986;44:788‐90.5. Defina J, Lincoin J. Prevalence of inadvertenthypothermia during the preoperative period:a quality assurance and performanceimprovement study. J Perianaesth Nursing1998;13:229‐35.6. Tappen RM, Andre SP. Inadvertenthypothermia in elderly surgical patients.AORN Journal 1996;63:639‐44.7. Hudson G, Beaver M, Scott J, Heichmer D.Warming up to better surgical outcomes.AORN Journal 1999;69:247‐8.8. Frank SM, El‐Rahmany HK, Cattaneo CG,Barnes RA. Predictors of hypothermiaduring spinal anesthesia. Anesthesiology2000;92:1330‐4.9. Stevens D, Johnson M, Langdon R.Comparison of two warming interventionsin surgical patients with mild and moderatehypothermia. Int J Nursing Pract 2000;6:268‐75.10. Kober A, Scheck T, Sessler DI. Effectivenessof resistive heating compared with passivewarming in treating hypothermia associatedwith minor trauma: a randomized trial.Mayo Clin Proc 2001;76:369‐75.11. Gluffre M, Finnie L, Smith D. Rewarmingpostoperative patients: Lights, blanket, orforced warm air. J Post Anaesth Nursing1991;6:387‐93.12. Ellis‐Stoll C, Anderson C, Cantu L, Englert S,Carlile W. Effect of continuously warmed IVfluids on intraoperative hypothermia.AORN Journal 1996;63:599‐606.13. Cohen S, Hayes JS, Tordella T, Puente I.Thermal efficiency of prewarmed cotton,reflective, and forced warm air inflatableblankets in trauma patients. Int J TraumaNursing 2002;8:4‐8.14. Summers S. The effects of two warmingmethods on core and surface temperature,hemoglobin oxygen saturation, bloodpressure, and perceived comfort ofhypothermic postanesthesia patients. JPostanaesth Nursing 1990;5: 354‐64.15. Bowen DR. Efficiency of the thermal jacketon the delivered temperature of prewarmed93

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005crystalloid intravenous fluid. AAMAJournal 1992;60:369‐73.16. Giuliano KK, Scott SS, Elliot S, Giuliano AJ.Temperature measurement in critically illorally intubated adults: a comparison ofpulmonary artery core, tympanic, and oralmethods. Crit Care Med 1999;27:2188‐93.17. Kabbara A, Goldlust SA, Smith CE, et al.Randomized prospective comparison offorced air warming using hospital blanketsversus commercial blankets in surgicalpatients. Anesthesiology 2002;97:338‐44.18. El‐Rahmany HK, Frank SM, Schneider GM,El‐Gamal NA, Vannier CA, Ammar R.Okasha AS. Forced‐air warming decreasesvasodilator requirement after coronaryartery bypass. Anesth Analg 2000;90:286‐91.19. Bernthal E. Clinical inadvertenthypothermia prevention: the anestheticnurse’s role. Br J Nursing1999;8:17‐25.Important AnnouncementHKCA Final Fellowship in Intensive CareAmendment of Examination FormatDuring the Board of Intensive Care meeting in April 2005, it was resolved that amendments in theexamination format may be made in the future. These amendments reflect the growth andmaturation of Intensive Care in Hong Kong and may provide a more objective and structuredexamination format. Each change will be introduced gradually in stages and the effects of eachamendment closely monitored.As of 2005 an OSCE format will be used to replace the Investigation table. It is expected that therewill be 10 questions in the OSCE. Suggested aspects for the test may include ECG’s, X‐rays,investigation results including blood gases, biochemistry, microbiology and hematology, clinicalwaveforms, equipment, resuscitation, crises management, communication station, clinical shortcases and others.The OSCE, like the investigation paper it replaces, will contribute 10% of the overall marks.94

Case ReportsBull HK Coll Anaesthesiol Volume 14, Number 2 July 2005An Epidural Abscess Following Catheter Insertion1KK Liu, 2 Joseph LuiDepartment of Anaesthesia, Caritas Medical Center, Hong KongSUMMARYWe report a case of an epidural abscess following catheter insertion in a 72‐year‐old woman scheduledfor an abdominal operation. A thoracic epidural catheter was inserted into the T8/9 intervertebral spaceunder strict aseptic technique. Adequate postoperative analgesia was achieved and the catheter wasremoved on day five following surgery. An epidural abscess was diagnosed on day fourteen as thepatient slowly developed both sensory and motor neurological deficits after catheter removal. Sheunderwent an emergency decompressive laminectomy and received a full course of intravenousantibiotics. The organism obtained at surgery was methicillin resistant Staphylococcus aureus (MRSA). Thediagnosis, clinical presentation, management and prevention strategies of catheter related epiduralabscess are discussed.Keywords: Anesthesia: Regional, Epidural, Complication: Abscess, NeurologicalBull HK Coll Anaesthesiol 2005;14:95‐100Epidural abscess is a rare complicationfollowing catheter insertion. It carries asignificant risk of developing permanentneurological deficits despite prompt recognitionand treatment. 1 There has been an increasingnumber of reported cases recently following thewidespread use of epidural analgesia forpostoperative pain relief. The diagnosis must bemade promptly in order to initiate appropriatemanagement. 2 However, the variability ofclinical presentation often makes diagnosisdifficult. We report a case of epidural abscess1MB BS, FHKCA, FHKAM (Anaesthesiology),FANZCA, Medical officer, 2 MB BS, FHKCA, FHKAM(Anaesthesiology), FANZCA, Consultant and Chiefof Service. Department of Anaesthesia Caritas MedicalCentre, Shamshuipo, Kowloon.Address correspondence to: Dr KK Liu, PrivatePractice, E‐mail: kkliu95@yahoo.comrelated to catheter insertion.Case ReportA 72‐year‐old woman with non‐insulindependent diabetes mellitus was scheduled forright hemicolectomy for colonic carcinoma.Combined general anesthesia with epiduralanalgesia was planned.Prior to induction of general anesthesia, athoracic epidural catheter was inserted with thepatient lying in the lateral position via aparamedian approach. The T8/9 epidural spacewas identified by using an 18G Tuohy epiduralneedle (BD Medical Systems‐Anesthesia, NewJersey, USA) using loss of resistance to saline.Asepsis was maintained throughout theprocedure. The patient’s back was prepared by10% povidine solution for approximately oneminute before needle insertion. The procedurewas completed after a single attempt without95

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005difficulty and the catheter was left in situ forperioperative pain relief. The catheter was tapedat skin level at 10 cm with 4 cm inside theepidural space. The catheter exit site was tapedwith a clear water‐proof dressing (Tegaderm,3M healthcare, UK) and an antibacterial filterwas connected within the drug delivery system.General anesthesia then followed and surgerywas completed without complication.On the fifth postoperative day, the epiduralcatheter was removed. At the skin puncture site,it was noted to be erythematous with somepurulent discharge. The patient was otherwiseasymptomatic with no evidence of fever or backpain. There was no local tenderness and herwhite cell count was normal. Daily inspectionwith dressing change was carried out by theacute pain service team for the subsequent fourdays after removal of the catheter. The patientremained asymptomatic and was dischargedfrom our care.Seven days after catheter removal, the patientcomplained of nausea and vomiting. Two dayslater, she developed acute urinary retention andrequired catheterization. Mild weakness (activemovement against gravity with some resistance)was documented in both hips and knees withnumbness to the level of her umbilicus. Thisquickly progressed into complete paralysis over thenext 24 hours with a sensory deficit of up to T10bilaterally. She continued to remain afebrile andher white cell count was again normal. She beganto complain of mild back pain along her lowerthoracic spine around the skin puncture site.Methylprednisolone 30 mg/kg was startedimmediately by the attending orthopedic surgeonin suspicion of acute spinal cord compressionfollowed by a continuous infusion of 5.4 mg/kg forthe next 24 hours. An urgent magnetic resonanceimaging (MRI) scan was carried out and showedan enhanced posterior dural collection at T6‐8, inkeeping with the diagnosis of an epidural abscess(Figure 1).Emergency decompressive laminectomy atmultiple levels was performed without furtherdelay. The diffuse abscess containing pus andgranulation tissue was drained. Methicillinresistant Staphylococcus aureus (MRSA) wassubsequently isolated. A full course ofintravenous vancomycin was prescribed for thenext 4 weeks. Her lower limb neurological statusimproved gradually over the next few months.Her muscle power returned to active movementagainst gravity with some resistance and shewas able to walk with a frame, six months afterher original surgery. She regained bowel controlbut self catheterization was still required forpersistent urinary retention secondary toneurogenic bladder.DiscussionThere has been an increasing number ofreports on catheter related epidural abscess butthe true incidence remains unknown. 3 It hasbeen reported to vary between 1:1,930 and1:5,000 per epidural catheter insertion. 4,5 Thiscan be partly explained by the growing numberof epidural block performed, increasing numberFigure 1. T2W magnetic resonance imaging showing an epidural abscess at T6‐8 levels (marked by thewhite arrows).96

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Figure 2. Skin puncture site with pus discharge(circle). This photograph was taken at the timeof decompressive laminectomy.of voluntary reporting and more liberal use ofimaging diagnostic tool including MRI scan. 5,6There are numerous etiologies in thedevelopment of an epidural abscess.Hematogenous spread of the causative bacteriato the epidural space seems to be the commonestcause where patients are very often nursed in anovercrowded ward. The bacteria can then travelfrom the skin puncture site into the epiduralspace over the next few days following catheterinsertion. 7 The spread of bacteria during theprocess of epidural catheterization via acontaminated needle or catheter is also apossible mechanism. 8,9 As in our patient, it ishighly likely that her local skin infection notedupon removal the catheter was the origin of thebacterial spread. Despite the skin had beencleaned with 10% povidine solution beforeneedle insertion, colonization of bacteria to thecatheter and subsequent infection could stilloccur.Various species of bacteria have been isolated.The commonest pathogen found isStaphylococcus aureus. It is responsible for 60% ofabscesses following catheterization. 4 Otherpossible organisms include Staphylococcusepidermidis, Pseudomonas aeruginosa, Streptococcuspneumoniae and Enterococcus species. 4,10 MRSA isan uncommon offending organism and onlyfour cases have been reported in theliterature. 11,12 It is also a potential pathogen in97immunocompromised patients undergoingmajor surgery and the spectrum seems to bebroadening. 11The immunological status of the patient isconsidered an important factor in developing anepidural abscess. The possible risk factorsinclude malignancy, diabetes mellitus, steroidadministration, chronic alcoholism and chronicrenal insufficiency. 4,13 Our patient has largebowel tumor as well as diabetes mellitus formany years.Heuser first described the clinical presentationof an epidural abscess in 1948. 14 Four differentphases were described. Phase I is back painoccasionally associated with local tendernessand fever. Phase II occurs over 2 to 3 days and isfeatured by radicular pain and fever. Phase III isconsidered a late stage accompanied byneurological deficit and sphincter dysfunction.Progression from Phase III to IV may be veryrapid and signifies complete paralysis within thenext 24 hours.However, not all these classical symptomsmanifest in every patient. It is only found in 37%of them. Motor deficits are absent in up to 29%of patients. 6 Epidural abscess is first suspectedin only about 40% of cases. 15 Other presentingfeatures that may be helpful includeinflammation of the catheter site, headache, stiffneck, nausea and abdominal pain. 11 Theinflammatory markers are useful butnonspecific. 4 In our patient, changes in phases Iand II were subtle. It was not until the patientpresented with urinary retention andsubsequently lower limb weakness (phase III)that spinal cord compression was suspected.Symptoms of abscess formation can occur atvarious times, ranging from one day to fivemonths after catheter placement. 11 Kindler et alnoted that 52% of epidural abscess occurred ator sooner than five days. 4 In another report, theincidence of infection following the use oftunneled catheters varied from 5.4% to 9.7%. 16,17Furthermore, 58% of patients showed symptomsafter removal of the epidural catheter. 11 Thehighly variable presentation often makesdiagnosis difficult. A high index of suspicion istherefore vital in early detection of an epidural

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005abscess. Communications between the acutepain service, ward clinicians and nurses arecritical.The definitive diagnosis relies on imagingstudies. MRI scan of the spine with or withoutgalolinium enhancement is now the goldstandard. 18,19 Both the extent and location of theabscess can be clearly defined. MRI scan issuperior to computerized tomographic (CT)myelography as the former allows directmultiplanar imaging and visualization of softtissue including the spinal cord and theparaspinal musculature. However, not allhospitals in Hong Kong has a 24‐hour MRIservice and very often, as in this case, the patienthas to be transferred to another hospital forimaging. This often creates further delay indiagnosis and treatment.Once the diagnosis of an epidural abscess ismade, an expedited management strategy mustbe initiated. The mainstay of treatment involvesemergency multilevel decompressivelaminectomy, evacuation of pus and parenteralantibiotics. Empirical broad spectrum antibioticswith bactericidal activity against Staphylococcusaureus and gram negative organisms must bechosen. They should be continued for no lessthan four weeks regardless of the requirement ofsurgery followed by oral therapy for at least twomore months. 6,20 The duration of antibiotictherapy is determined by the clinical response,biochemical markers and radiological resolutionof the lesion. Further treatment is required whenthere is concomitant osteomyelitis, persistentlyelevated inflammatory markers and bacteremia. 6In some cases, patients can be treatedconservatively without surgical decompression.21,22 The nonsurgical approach can beconsidered for patients with severe medicalcomorbidities, absence or minimal neurologicalsymptoms, extensive abscess precluding surgeryand paraplegia of more than 72 hours when thechance of neurological improvement aftersurgery is minimal. 7,23 If the conservativeapproach is chosen, serial MRI scans withregular and frequent neurological examinationsare essential. Further surgical intervention canthen be initiated if necessary. High dose98intravenous steroid therapy is relativelycontraindicated as it may exacerbate theongoing infection and sepsis. 24The neurological outcome is closely related tothe time between the development of symptomto surgical decompression. In a studyinvestigating long term outcome afterneurosurgery for epidural abscess followingcatheter insertion, only 31% of the patientsreferred to neurosurgery improved aftersurgery. 1 Only 20% with paraplegia made acomplete recovery without deficits at hospitaldischarge. Long term follow up revealed that55% of patients with paraplegia had experiencedsome improvement in motor function at somestage but 44% still suffered from bladder and, orbowel dysfunction. 1 Our patient had someimprovement in motor function after dischargebut still suffered from bladder dysfunction sixmonths after her initial surgery.Infection control measures aiming atminimizing the risks of infection followingepidural catheter insertion have beenrecommended. 25,26 The guidelines include:(1) strict aseptic technique;(2) closed delivery system;(3) use of a 0.22 μm bacterial filter within thesystem;(4) inspection of the epidural punctured siteevery eight hours;(5) change of filter, infusion line and infusate at96 hours or discontinue use and(6) preparation of the infusate under sterileconditions in the pharmacy. 26In our case, the infusate was prepared in 500ml bag by the anesthesiologist in a clean but notsterile condition and the catheter site wasinspected only once a day by our acute painservice team.Furthermore, more isolates from cultureswere obtained following skin disinfected with 10% povidine iodine than in those disinfected with0.5% chlorohexidine in 80% ethanol. 27 It has alsobeen recommended that the disinfectant shouldbe left in contact with skin for at least oneminute before skin puncture. Our hospital hasnow replaced all povidine solution by 0.5%chlorohexidine in 80% alcohol as disinfectant in

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005all operating rooms and our rule of strict aseptictechnique while performing any invasiveregional procedure is further emphasised. 12If an infection is suspected, the catheter tipand any discharge at the puncture site shouldalso be sent for culture. If neurological signs arepresent, an urgent MRI scan must be orderedand antibiotic therapy initiated so that surgicalevacuation, if necessary, can be plannedpromptly. 25 A recent report has also suggestedthat an urgent MR scan is required if the patientpresents with systemic and local signs ofinfection even in the absence of neurologicalsigns and symptoms. 22In summary, epidural abscess remains one ofthe most serious complications of epiduralcatheter insertion. Prevention of its developmentis critical. We must emphasize the importance ofasepsis during catheter insertion and thevigilance of frequent regular follow up by theacute pain service. Attending clinicians andnurses must also have a high index of suspicionto make an early diagnosis and to initiatetreatment promptly in order to prevent furtherdeterioration of symptoms.References1. Wang LP, Hauerberg J, Schmidt JF. Longterm outcome after neurosurgically treatedspinal epidural abscess following epiduralanalgesia. Acta Anaesthesiol Scand 2001;45:233‐9.2. Mackenzie AR, Liang RBS, Smith CC, KaarGF, Smith FW. Spinal epidural abscess: theimportance of early diagnosis and treatmentJ Neurol Neurosurg Psychiatry 1998;65:209‐12.3. Smedstad KG. Infection after centralneuraxial block. Can J Anesth 1997;44:235‐8.4. Kindler CH, Seeberger MD, Staender SE.Epidural abscess complicating epiduralanesthesia and analgesia. Acta AnaesthesiolScand 1998;42:614‐20.5. Wang LP, Hauerberg J, Schmidt JF.Incidence of spinal epidural abscess afterepidural analgesia. Anesthesiology1999;91:1928‐36.6. Sampath P, Rigamonti D. Spinal epiduralabscess: a review of epidemiology, diagnosisand treatment. J Spinal Disord 1999;12(Pt2):89‐93.7. Hlavin ML, Kaminski HJ, Ross JS, Ganz E.Spinal epidural abscess. A ten yearperspective. Neurosurgery 1990; 27:1771‐84.8. Holt HM, Anderson SS, Anderson O, Gahrn‐Hansen B, Siboni K. Infections followingepidural catheterization. J Hosp Infect 1995;30:253‐60.9. Hunt JR, Rigor BM, Collins J. The potentialfor contamination of continuous epiduralcatheters. Anesth Analg 1997;56:222‐5.10. Pegues DA, Carr DB, Hopkins CC.Infectious complications associated withtemporary epidural catheters. Clin Infect Dis1994;19:970‐2.11. Okano K, Kondo H, Tsuchiya R, Naruke T,Sato M, Yokoyama R. Spinal epiduralabscess associated with epiduralcatheterization: report of a case and a reviewof the literature. Jpn J Clin Oncol 1999;29:49‐52.12. Philips JMG, Stedeford JC, Hartsilver E,Roberts C. Epidural abscess complicatinginsertion of epidural catheters. Br J Anaesth2002;89:778‐82.13. Dawson P, Rosenfeld JV, Murphy MA,Hellyar AG. Epidural abscess associatedwith postoperative epidural analgesia.Anaesth Intensive Care 1991;19:569‐72.14. Heusner AP. Nontuberculous spinalepidural infections. N Eng J Med 1948;239:845‐54.15. Danner RL, Hartman BJ. Update of spinalepidural abscesses. 35 cases and review ofthe literature. Reviews of infectious Diseases1987;9:265‐74.16. Du Pen SL, Peterson DG, William A,Bogosian AJ. Infection during chronicepidural epidural catheterization: Diagnosisand treatment. Anesthesiology 1990;73:905‐9.17. Bryers K, Axelrod P, Michael S, Rosen S.Infections complicating tunnelled intraspinalcatheter systems used to treat chronic pain.Clin Infect Dis 1995;21:403‐8.18. Maslen DR, Jones SR, Crislip MA,Bracis R,Dworkin RJ, Flemming JE. Spinal epiduralabscess. Optimizing patient care. Arch Int99

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Med 1993;153:1713‐21.19. Numaguchi Y, Rigamonti D, Rothman M.Spinal epidural abscess: evaluation withgadolinium‐enhanced MR imaging.Radiographics 1993;13:545‐9.20. Darouiche R, Hamill RJ, Greenberg SB,Waethers SW, Musher DM. Bacterial spinalepidural abscess. Review of 43 cases andliterature survey. Medicine 1992;71:369‐85.21. Hori H, Kano T, Fukushige T, Sano T.Successful treatment of epidural abscesswith a percutaneously introduced 4‐frenchcatheter for drainage. Anesth Analg1997;84:1384‐6.22. Royakkers AANM, Willigers H, Van DerVen AJ, Wilmink J, Durieux M, Van Kleef M.Catheter‐related epidural abscess ‐ Don’twait for neurological deficits. ActaAnaesthesiol Scand 2002;46:611‐5.23. Leys D, Lesion F, Viaud C, Pasquier F,Rousseaux M Jornin M, Perit H. Decreasedmorbidity from acute bacterial spinalepidural abscess using computedtomography and nonsurgical treatment inselected patients. Ann Neurol 1985;17:350‐5.24. Bracken MB, Shepard MJ, Collins WF, et al.A randomized controlled trial ofmethyprednisolone or nalaxone in thetreatment of acute spinal‐cord injury.Results of the Second National Acute SpinalCord Injury Study. N Eng J Med 1990; 322:1405‐11.25. Sarubbi FA, Vasquez JE. Spinal epiduralabscess associated with the use of temporaryepidural catheters : Report of two cases andreview. Clin Infect Dis 1997;25:1155‐8.26. Brooks K, Pasero C, Hubbard L, Coghlan RH.The risk of infection associated withepidural anaesthesia. Infect Control HospEpidemiol 1995; 16:725‐6.27. Sato S, Sakuragi T, Dan K. Human skin floraas a potential source of epidural abscess.Anesthesiology 1996;85;1276‐82.100

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Novel Use of Endobronchial Tube in Management ofa Patient with Giant Lung BullaLance S.K. Chua, T.Y. Chan, W.M. Chan, Richard G.B. OoiDepartment of Anaesthesia, Intensive Care and Operating Theatre Services, Yan Chai HospitalSUMMARYThe management of a patient with anticipated difficult airway and a giant lung bulla in the right upper lobe,presenting with respiratory failure is described. Ventilation of the patient’s lungs was facilitated by isolation ofthe right‐upper lobe using a left sided double‐lumen endobronchial tube.Keywords: Giant lung bulla; Anesthetic equipment; Intubating laryngeal mask airway; Double lumentubes; Selective ventilation.Bull HK Coll Anaesthesiol 2005;14:101‐5Double lumen endobronchial tracheal tube(DLT) placement is a technique employedfor isolation or independent ventilation ofthe lungs. These tubes are designed to minimizeoccluding the upper lobe of the endobronchial side.Anatomically, the right upper lobe is particularlysusceptible and consequently right sided DLT’shave an additional opening in the endobronchialcuff to ensure right upper lobe ventilation.However, we encounter a situation where it wastherapeutic to occlude the right upper lobe, whileallowing the middle and lower lobes to beventilated, using a DLT designed for leftendobronchial placement.1MBBS, HKCA, FHKAM (Anaesthesiology), MedicalOfficer, 2 MB BS, FHKCA, FHKAM (Anaesthesiology),FANZCA, Consultant. 3MBBS, FHKCP,MRCP,FHKAM (Medicine), Senior Medical Officer,4MBBS, FRCA, FHKCA, FHKAM (Anaesthesiology),Senior Medical Officer. Department of AnaesthesiaIntensive Care and Operating Theatre Services, YanChai Hospital, Tsuen Wan.Address correspondence to: Dr Lance Chua, PrivatePractice, E‐mail: lordelk@gmail.comCase PresentationA 65 year old male (60 kg) presented to theIntensive Care Unit (ICU) with respiratory failuresecondary to pneumonia. He suffered fromnasopharyngeal carcinoma ten years previouslyand had been treated with nasopharyngectomyand radiotherapy. He also had a history ofprevious pulmonary tuberculosis and chronicobstructive pulmonary disease (COPD),complicated by a giant bulla in the right upper lobezone.On admission to ICU, he was obtunded and inrespiratory distress. His respiratory rate was 38min ‐1 , arterial blood pressure was 100/70 and heartrate was 100 min ‐1 . His electrocardiogram showedsinus rhythm without cor pulmonale or evidence ofacute ischemia. His arterial blood gas resultsshowed type II respiratory failure with carbondioxide tension of 13 kPa. His chest radiograph(CXR) revealed a right giant bulla occupying half ofthe hemithorax and dense haziness in the left lungfield and remaining right lung, in addition tounderlying COPD changes (Figure 1).A decision was made to initiate mechanicalventilation and assessment of his airway suggested101

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Figure 1. Line showing the lower limit of theright upper lobe bullae.Figure 2. Double lumen tube in position withinthe right main bronchus (arrows).possible difficult direct laryngoscopy due to limitedmouth opening (2 cm), a full set of teeth, limitedrange of motion of his neck (partly due to veryfibrotic anterior neck tissues) and thyromentaldistance of 5 cm. Tracheal intubation was achievedusing a size 4 intubating laryngeal mask airway(FastTrach, Euromedical for Maersk Medical,Kedah Malaysia) through which was passed an 8mm internal diameter endotracheal tube (SimsPortex Limited, Hythe Kent, United Kingdom).Propofol 50 mg IVI and succinylcholine 100 mg IVIwere used to facilitate tracheal intubation as he wasstruggling and clamping his mouth tightly shut.His pneumonia continued to worsen, witharterial oxygenation maintained at only 84%despite an inspired oxygen fraction of 1.0 andoptimization of ventilatory parameters (cycle time,tidal volume and positive end expiratory pressure,PEEP). Serial CXRs revealed an apparent increasein size of the bulla. It was thought that his gasexchange might be improved with isolation of thebulla while ventilating as much as possible of hisremaining lung tissue.Following intubation, he was ventilatedmanually for several minutes with 100% oxygen.An adult sized airway exchange catheter (Cooks102Tube exchanger with rapifit adaptor, Cook CriticalCare, Bloomington, In, USA) was passed throughthe tracheal tube and connected to a Manujet(Medizintechnik GMBH, Sulz, W. Germany). Hisarterial oxygen saturation was maintained at about94% with the intermittent positive pressure manualjet ventilation. The tracheal tube was thenwithdrawn over the airway exchange catheter anda 37 French double lumen tube (MalincrodtMedical, Athlone, Ireland) was then threaded overthe catheter such that it passed through thebronchial lumen of the DLT. The airway exchangecatheter was subsequently removed and the DLTwas connected to a ventilator (Siemens Servo 300,Siemens‐Elema Electromedical Systems Division,Solna, Sweden). Fibreoptic bronchoscopy was usedto guide the DLT into the right bronchus and theposition was confirmed by ensuring that the rightupper lobe bronchial lumen was not visiblethrough the opening of the bronchial lumen.Subsequent chest radiograph further confirmed thelocation of the DLT (Figure 2).Afterwards, his oxygen saturation improved to92% without significant increase in airway pressureor size of the bulla (Figure 3). Table 1 shows his

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Table 1. Arterial blood gas, hemodynamic and ventilator parameters before and after double lumen tubeinsertion. SaO2 = Oxygen saturation, PaO2 = Arterial oxygen tension, PaCO2 = Arterial carbon dioxide tension, PEEP =positive end expiratory pressure, fiO2 = inspired oxygen fraction, PC = pressure control mode, PRVC = pressure regulated volumecontrol modeBlood GasBefore DLTAfter DLTpH 6.98 7.31SaO2 (%) 83.8 92PaO2 (kPa) 8.5 7.2PaCO2 (kPa) 22.3 8.8VentilatorMode/fiO2 PC/1.0 PRVC/1.0Airway Pressure (cmH2O) 41 28Pressure Support (cmH2O) 28 20PEEP(cmH2O) 10 6HemodynamicsAverage mean arterial68 110pressure (mmHg)Average heart rate (min ‐1 ) 110 90oxygenation, hemodynamic and ventilatorparameters before and after DLT insertion.Unfortunately, he eventually succumbed 48hours later as a result of sepsis induced multiorganfailure.DiscussionLung bullae are thin walled, air filled spacesresulting from destruction of alveolar tissue.They can be classified according to theiraetiologic origins i.e. bronchogenic, postinfective,infantile and emphysematous. The walls oflung bullae usually comprise visceral pleura,connective tissue septa and compressedparenchyma.Lung bullae have a tendency to increase insize with age, which may be a result of a oneway valve effect. They represent areas ofincreased compliance, which then form the pathof least resistance during positive pressureventilation. Since they do not take part ingaseous exchange, there is a resultant increase inalveolar dead space. The gradual increase in sizeof bullae during positive pressure ventilationmay lead to compression of adjacent normallung tissue resulting in further worsening of103ventilation/perfusion mismatching and hencegreater hypoxemia.A variety of complications, including gradualdecrease in effort tolerance of the patient,recurrent infections and pneumothoraces canoccur when bullae enlarge. Giant lung bullaeconstitute one of those thoracic diseases thatusually results in an improvement in lungfunction following resection, although oftenpreceded by exceedingly poor lung function inthe preoperative period.Some of the accepted indications forbullectomy include incapacitating dyspnea,giant size at presentation, repeated pneumothoraxand compression of a significant volumeof otherwise normal lung tissue. The complexityof the management of lung bullae for volumereduction surgery or in the immediate postoperativeperiod is dependent on whether thedisease is unilateral or bilateral. The latter mayrequire resorting to extra‐corporeal oxygenationduring the procedure itself and carries with itthe added risks of anticoagulation.The main principles of anesthetic andintensive care management of patients with

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005unilateral bullous disease include avoidance ofnitrous oxide and positive pressure ventilation,wherever possible. If positive pressureventilation cannot be avoided, it isrecommended that small tidal volumes andrapid ventilatory rates be used, so as to maintainadequate minute ventilation. The aim is to keepthe airway pressures at or below 10 cmH2O. Insome cases, high frequency jet ventilation hasbeen used. Since there are no randomizedcontrolled studies to compare the outcomesusing different ventilatory strategies in bullousdisease, it is difficult to postulate which are thesuperior methods.In patients with unilateral bullous disease,endobronchial intubation is a treatment option.The primary objective of which is to isolate andselectively eliminate ventilation to the affectedlung or lobe.The choice of technique used for lungisolation depends on factors including thenature of the pre‐existing pathology, urgency ofthe situation, anatomical considerations and theknowledge and expertise of the user. Isolationtechniques are associated with complicationssuch as trauma to the airway, malpositioningand hypoxemia. To minimize the risks ofmalpositioning, several methods are availablefor checking the positioning of the tube. Theseinclude the use of fibreoptic bronchoscopy andchest auscultation. In general, the consensus isthat for left‐sided tubes, bronchoscopy is notalways necessary. On the other hand, whenusing right sided tubes, it is recommended thatpositioning be routinely checked with the helpof a fibreoptic bronchoscope.The main problems of this patient includedthe presence of a giant bulla resulting indisparity in lung compliance between the bullaand the remaining lung tissue resulting in ‘steal’of inspired lung volumes. The consequence wasa progressive increase in minute ventilationrequirements in order to maintain arterialcarbon dioxide tensions. Ventilation of the bullanot only represented ‘wasted’ ventilation, butposed a big risk for barotrauma and suddenpneumothorax. The occurrence of this wouldsurely have further compromised his alreadyprecarious clinical status. Other factors thataffected this patient’s treatment optionsincluded: a potential difficult airway from hisprevious radiotherapy and the necessity tomaintain uninterrupted ventilation whilstsubstituting tracheal tubes.The ventilatory aims for this patient were toisolate and occlude the right upper lobe, whileallowing continued ventilation of the remainderof his right lung. Previous reports have found animprovement in ventilation/perfusion mismatch2‐3 and hence oxygenation when severelydiseased lung is isolated from ventilation, orindeed when the lungs are subjected todifferential ventilation.Besides DLT’s, other methods available toachieve lung isolation include bronchial blockerssuch as the ‘Univent’ system, Foley 4 or Fogartycatheters and simultaneous intubation with twoDLT’s. All of these methods are of courserendered more reliable by means of fiberopticendoscopic visualization and guidance 5 . This isparticularly so with the right main bronchus dueFigure 3. Close‐up of bulla 24 hours afterDouble lumen tube insertion. Noted that there isno worsening of bulla (lower limit arrowed).104

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005to its anatomy and the proximity of the rightupper lobe bronchus to the carina.As a result of these anatomicalconsiderations and his labile oxygenation, it wasnot possible to subject the patient to protractedmanipulations using a bronchial blocker. A rightsided DLT would be inappropriate since it isdesigned with the intention of avoidingocclusion of the right upper lobe, by having anorifice in the bronchial cuff.Some of the potential problems with ourtechnique of using a left sided DLT to achieveright endobronchial intubation is kinking of thetube with increase in airway pressures. This canbe avoided during insertion by ensuring that theDLT is inserted with the major convexity facingthe intubator, such that the preformed leftcurvature now faces the right of the patient.Although this patient did not demonstrate anyincrease in airway resistence 6 as demonstratedby the airway pressure remaining the same aswhen using a single lumen tracheal tube, this isstill a theoretical possibility especially if thecurvature of the DLT is straightened.The method reported above for isolation ofthe right upper lobe bronchus of this patientoffers an effective approach to management of apatient with right upper lobe bulla, in the face oflabile oxygenation status. Since mostanesthetists are familiar with DLT placement,this technique has the advantage of beingexpeditiously performed, avoiding protractedmanipulation inherent in other techniques inpatients with labile arterial oxygenation.References1. Schulte am Esch J, Keiser ER, Horstmann R.The indication for the use of anendobronchial double lumen tube in theintensive care of unilateral pulmonarycomplications. Anaesthetist 1982;8:400‐7.2. Powner DJ, Eross B, Grenvik A. Differentiallung ventilation with PEEP in treatment ofunilateral pneumonia. Crit Care Med1977:31:170‐2.3. Nazari S, Trazzi R, Moncalvo F, et al. A newmethod for separate lung ventilation. JThoracic Cardiovasc Surg 1988;95:133‐8.4. Chen KP, Chan HC, Huang SJ. FoleyCatheter used as bronchial blocker for onelung ventilation in a patient with atracheostomy. Acta Anaesthesiol Sin199533:41‐4.5. Slinger PD. Fibreoptic bronchoscopicpositioning of double‐lumen tubes. JCardiothorac Anesth 1989;4:486‐96.6. Hammond JE, Wright DJ. Comparison of theresistences of double‐lumen endobronchialtubes. Br J Anaesth 1984;56:299‐302.7. Caseby NG. Anaesthesia for the patient withcoincidental giant lung bulla: a case report.Can Anaesth Soc J 1981;3:272‐6.8. Otruba Z, Oxorn D. Lobar bronchialblockade in bronchopleural fistula. Can JAnaesth 1992;39:176‐8.9. Joel A. Kaplan (Ed.) Thoracic Anaesthesia,Second Edition, Churchill Livingstone 1991.105

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005WORKSHOPS ORGANISED BY THE INSTITUTE OF CLINICAL SIMULATIONA Collaboration between the Hong Kong College of Anaesthesiologists and the North District Hospital(Application form can be downloaded from the College website: www.hkca.edu.hk)Anaesthetic Crisis Resource Management (ACRM)Date: First Saturday of each month ‐ slots available from March 2005(3 September, 10 September, 5 November and 3 December, 2005)Time: 08:00 – 18:00Venue:The Institute of Clinical SimulationCME points:HKCA 10 pointsMax participants: 4Fee:HK$2000 per headFormat:Each registrant will participate in(1) An introduction on the METI Simulator, the anesthetic machine for use in theworkshop and the theories of crisis management(2) Allocated time for hands‐on crisis scenario management on the METI Simulator,rotating through different roles and handling different scenarios(3) A group debriefing session at completion of each scenario“Group” registration welcome if you can find your own partners to form a group of four. Mutually agreed datesmay be arranged. Sessions will be videotaped. All participants in the workshop will be required to sign aconfidentiality statement.Difficult and Advanced Airway Management (DAAM) WorkshopTime: 22 October 2005Venue:Institute of Clinical SimulationCME points: HKCA 4.5 pointsMax participants: 16Fee:HK$1,200 per headObjectives:(a) Recognition of patients with potential difficult airway or impossible tracheal intubation(b) Practice of Airway Algorithm on situations of failure to oxygenate patients(c) Description and application of suitable ventilatory techniques to oxygenate patients with predicted andunpredicted difficult airways.Programme:(1) Lectures on basic knowledge of airway management(2) Videotapes on different techniques of recent and advance airways(3) Tutorial discussion on common causes of airway problem(4) Skill stations on various techniques(5) MCQ and OSCE assessment after the courseHighlights of interesting techniques and skill stations:(1) Virtual bronchoscopy training on computer model(2) Practice bronchoscopy on pig’s lung(3) Different gadgets on one‐lung ventilation in difficult situations (Univent, Arndt’s wire‐guided endobronchialblocker)(4) Bullard laryngoscope workstation(5) Cricothyrotmy sets and techniques106

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005THE HONG KONG COLLEGE OF ANAESTHESIOLOGISTSMinutes recording the proceedings of the 16 th Annual General Meeting of the Hong Kong College ofAnaesthesiologists, held in the Hospital Authority Building, on 28 th June 2005 at 18:45 hoursPresentProf. Tony Gin (President and Chairman)Dr PT Chui Dr Joseph Lui Dr John LiuDr YF Chow Dr PP Chen Dr Edward Hoand 9 other Fellows and MembersIn Attendence Mr Daniel Tso, Administrative executive, HKCAThe president welcomed all in attendance to the 16 th Annual General Meeting of the Hong Kong Collegeof Anaesthesiologists,AGM 16.01 Confirmation of minutes of the 15 th annual general meeting held on 21 st June 2004The minutes had be previously circulated and tabled.Proposed by Dr John Liu and seconded by Dr John Low. The minutes was accepted.AGM 16.02 Matters arising from the minutesNilAGM 16.03 Report of the CouncilThe President highlighted a number of issues:(a) A vote of thanks to the outgoing Council members.(b) The College has revamped the training programs.(c) There were a number of changes in prospective examinations in relation to thearrangements of external examiners. There will be courses introduced to local examiners.They will be conducted by overseas experts in the fields of education and training.(d) The Boards of Pain Medicine and Intensive Care Medicine had been created and theBoards are working to revamp their programs in relation to training and examinations.(e) The Board of Accreditations had conducted a revalidation of all training units andrecommendations were made.(f) The Board of Education had implemented the new modular training system, periodicreviews will be in place.(g) The College will provide secretarial support to ANZCA in relation to the ANZCAExaminations held locally.(h) The College will maintain continual participation with the Conference of InternationalReciprocating Examination Boards in Anesthesia (CIREBA) to keep an active role in theinternational scene.(i) Council members had visited Beijing with the Ministry of Health in the Academy leveland the anesthetic counterparts at Peking Union Medical College Hospital.Proposed by Dr John Liu, and seconded by Dr Edward Ho. The report was approved.AGM 16.04 Auditor Report for the year ended 31 st December 2004The Auditors report includes the Income and Expenditure Accounts and Balance Sheets (.The report was tabled at Council and had been previously circulated to the entiremembership before the meeting. The Honorary Treasurer gave a summary of the accounts.Proposed by Dr TW Lee, and seconded by Dr John Low. The report was accepted.AGM 16.05 Council Election 2005 ‐ 2007107

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005At the close of nominations on 18 th March 2005, there were 16 nominations from fellows, and onefrom members. Dr John Liu was elected unopposed as he was the only nominated candidate bymembers. (By‐law 4.1.3 “... one member of the Council, being a Fellow, shall be nominated and elected bythe class of Members only”). Fellows were asked to elect 14 Council members from the remaining 15nominations. By the deadline (5:00 PM on 13 May 2005), a total of 112 returns were received at theCollege office.The following are the elected members for the Council 2005 ‐ 2007CHAN, Kin Cheong Simon HO, Tat Fai EdwardCHAN, Tak Vai Matthew CHEN, Phoon PingCHEUNG, Po WahCHOW, Yu FatCHUI, Po TongGIN, TonyHUI, Theresa Wan Chun IRWIN, MikeJOYNT, GavinKOO, Chi HungKWAN, Anne Siu King LEE, Tsun WoonLIU, Tak Chiu JohnThe election report was accepted.AGM 16.06AGM 16.07To adopt the resolution of Council to confer Honorary Fellowship to Professor Teik E OhDr YF Chow informed members that Professor Teik Oh has agreed to come again thisyear for the Honorary Fellowship, for which he was unable to attend last year.Proposed by Dr TW Lee and seconded by Dr Edward Ho. The resolution was passed.Appointment and Fixing of Remuneration of AuditorsKadir and Co was re‐appointed as auditor. The fixing of their remuneration was left toCouncil.AGM 16.08.01 Approval of the subscription for 2005Members and fellows approved Council’s recommendation of the subscriptions for 2006:Local FellowHK$2,500Local MemberHK$1,250Overseas Fellow HK$ 625Overseas Member HK$ 313Senior Member/Fellow HK$ 50AGM 16.09.01 Any Other BusinessPresident reported that there was no other business. The meeting closed at 19:05 hour.108

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Approved Formal ProjectCHU, Annie SYWONG, CMLOW, KevinCHENG, DawnTSANG, KristieLEE, SunnyWONG, NMKWAN, GladysLAM, BrianHUI, GraceRandomized control trial to evaluate the use of patient‐controlled sedation in inguinalhernia repair surgery under local anaesthesiaDetermination of an optimal dose of Fentanyl for use with Propofol when inserting thelaryngeal mask airwayArterial Carbon Dioxide Tension, Intracranial Pressure and Neurosurgical OperatingConditionsA Survey of Ambulatory Laparoscopic Cholecystectomy at Tuen Mun HospitalPerformance of BIS ® XP during simulated high frequency electrocautery interferenceThe effect of Trendelenburg position on the cross‐sectional area of the right internaljugular veinVIPoma and its Perioperative ManagementPostoperative neuropathy after combined spinal‐epidural anaesthesia in a patientundergoing Pelvic tumour resectionTracheal rupture complicated with tension pneumothorax during transhiatalesophagectomy: a case reportPost‐dural puncture headache: incidence and risk factors in Hong Kong obstetricpatientsSO, Frankie A case report of being awake at bispectral index of 40WAI, CKPerioperative management of a patient with Devicʹs disease undergoing lower segmentcaesarean sectionBasic Science Course in Anesthesiology 2005The Basic Science Course in Anesthesiology organized by the Hong Kong College of Anaesthesiologistswill commence on 10 th September, 2005. This course consists of 32 hours of lecture time on Saturdaymornings over 9 weeks. The venue is either at PWH, QEH or QMH. Knowledgeable tutors are invitedto give the lectures. It is targeted for first to third year anesthesia trainees.The final schedule will be posted up at the HKCA web site as soon as it is available.Course fee: HK$ 1,000 for HKCA membersHK$ 2,000 for non‐membersInterested trainees should complete the application form and send it to Dr CH Koo, Basic science coursecoordinator, Department of Anaesthesia, QEH, together with exact payment (crossed cheque payable toʺThe Hong Kong College of Anaesthesiologistsʺ) before 4 th September, 2005.Application forms are now available from SOTs of your department, Administrative Executive of theCollege or can be downloaded from the HKCA website (http://www.hkca.edu.hk).Updated information is also available at the HKCA website.109

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Board of ExaminationSuccessful candidatesFinal Fellowship Examination in Anaesthesiology March/ April 2005CHEUNG Suk Yan OliviaLAM Cheung KwanLAM Kar Yee KatherineNG Yuen ChongTANG Yee KwanWU Wai San JanetYU Lin YauCMCPMHPWHPWHPYNEHQEHPWHSeven out of 14 candidates passed the examination. The HKCA Final Fellowship Examination Prize wasawarded to Dr Katherine LAM of the Prince of Wales Hospital. The College is grateful to Dr. HazelAdams of RCA, and Professor Peter Klineberg of ANZCA for their assistance as External Examinersduring the examination.Examination Dates, 2005Final Fellowship Examination in Intensive Care 2005Examination Fee: $10,000WrittenOral/Clinical/OSCEClosing DateDate17 October 2005(Mon)2‐3 December 2005(Fri/Sat)20 September 2005(Tue)Diploma of Pain Management (HKCA) Examinations 2005Examination Fee: $5,000WrittenClosing DateDate4 November 2005 (Fri)4 October 2005 (Tue)Exit Assessment Date for Year 200513 October 2005 (Thur)Trainees who are qualified to apply for fellowship are recommended to have their respectively applications received atthe HKCA office at least 21 days before the scheduled Exit Assessment dates, to allow ample time for processing.PT ChuiChairman, Board of Examination110

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 20052005 Report on the Final Fellowship Examinations in Intensive Care:A Historical PerspectiveIntroductionThe inaugural Final Fellowship Examinations in Intensive Care was conducted in 1997. Since then, muchwork continues in order to maintain the examination as a reasonable means of assessment in the trainingof Intensive Care. Because the number of eligible trainees is small, no examinations were conducted in2000, 2001 and 2002.Successful candidatesThe successful candidates till date have been1997 Dr Cheung Po Wa1998 Dr Claudia Cheng Ai Yu1999 Dr Victor Yeo2003 Dr Chau Chin Man and Dr Kwok Keen Man2004 Dr Wilson Lee Hon MingExamination ReportsEach year the number of examination candidates is small and while each of the examination reports havebeen sent to the supervisors of training, the reports will not be made public.Pass rateThe pass rate for each year is as follows:Number ofCandidatesNumberSuccessful1997 2 11998 3 11999 1 12003 2 22004 1 1The overall combined pass rate is 66.7% (range 33.3 to 100%).Examination FormatThe Final Examinations consist of several parts. The weight of each part as a percentage of the overallmark is presently released for the first time. This weighting system has been in use so far, but is currentlysubject to further review and may be amended without notice.Written PapersShort answer question paper (15 questions, 150 minutes) 20%Long answer question paper (2 questions, 120 minutes) 20%Clinical/Practical PapersInvestigations (30 minutes) 10%Clinical Medicine (60 minutes) 30%Oral examinations (2 tables of 30 minutes each) 20%Examination Past Papers: WrittenThe past papers for the written section have been published in the College website for reference.111

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005General PerformanceIn general, over the last few years, similar strengths and weaknesses tended to be seen in our examinationcandidates. The written papers are generally well answered. However, the clinical medicine paper wouldrepresent one of the more difficult paper parts of the examination. Commonly seen problems includemaking simple errors in bedside physical examination, for example failure to adequately expose thepatient, or missing the presence of a physical sign. In addition, weakness in the integration of theoreticalknowledge is another commonly seen problem. Candidates must ensure that the relevant infectioncontrol practice must be adhered to; time will be allotted for this and marks may be deducted if this is ofa poor standard.Upcoming ChangesDuring the Board of Intensive Care meeting in April 2005, it was resolved that amendments in theexamination format may be made in the future. These amendments reflect the growth and maturation ofIntensive Care in Hong Kong and may provide a more objective and structured examination format. Eachchange will be introduced gradually in stages and the effects of each amendment closely monitored.As of 2005 an OSCE format will be used to replace the Investigation table. It is expected that there will be10 questions in the OSCE. Suggested aspects for the test may include ECG’s, X‐rays, investigation resultsincluding blood gases, biochemistry, microbiology and hematology, clinical waveforms, equipment,resuscitation, crises management, communication station, clinical short cases and others.The OSCE, like the investigation paper it replaces, will contribute 10% of the overall marks.A workshop comprising of a mock OSCE will be arranged and the date will be announced soon.External ExaminersThe Hong Kong College of Anaesthesiologists wishes to thank the following external examiners1997 Dr Richard Lee, Joint Faculty of Intensive Care Medicine1998 Dr Peter Morley, Joint Faculty of Intensive Care Medicine1999 Dr Loretta Yam, the Hong Kong College of Physicians2003 Dr John Myburgh, Joint Faculty of Intensive Care Medicine2004 Dr Chan Wai Ming, the Hong Kong College of PhysiciansIn gratitudeThe Hong Kong College of Anaesthesiologists would also like to thank Dr Tom Buckley for serving aschief examiner from 1997 till 2002, in particular, for organising the inaugural examinations whichrepresent a landmark for intensive care training in Hong Kong, and for providing a well organisedsystem for further growth.Dates of next examinationsThe 2005 examination dates are as follows:Written papers Monday 17 th October 2005Clinical/Practical papers Friday‐Saturday 2‐3 rd December 2005The closing date for applications is Tuesday 20 th September 2005.Dr Peggy TanChief of Examinations in Intensive Care112

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Board of Pain Medicine1. The BoPM would like to remind all new trainees for Dip Pain Mgt to register before starting training.It is possible that your training time may not be recognized if you have completed the trainingwithout being registered as a Dip Pain Mgt trainee with HKCA.2. The BoPM would like to announce that Dr Steve Onsiong had resigned from the Board. The Boardwould like to thank Dr Onsiong for his contributions over the years and wish him well in his futureendeavour. On another note, the BoPM would like to welcome Dr MC Chu and Dr Timmy Yuenappointments to the Board following approval of the HKCA Council. Dr MC Chu is also our newDip Pain Mgt Training Officer.3. At the recent inspection in March 2005, both UCH and QEH have been successfully accredited astraining centers for Dip Pain Mgt (HKCA) for another 5 years.4. The next DPM examination will be held on 4 th November 2005. Dr Roger Goucke will be invited asthe external examiner.5. The BoPM is organizing a full‐day seminar entitled “The Essentials of Pain Management” on 4December 2005 at the Miramar Hotel. There is a multidisciplinary faculty of overseas and localspeakers. Please see poster for more information.6. The BoPM is also planning a workshop on patient evaluation skills on 5 November 2005. Theworkshop will include skills stations on radiological imaging, neurophysiological tests, neurologicalexamination, spine evaluation, etc. Watch out for notice of the workshop.PP ChenChairman, Board of Pain MedicineAdmission to Fellowship by Examination, FHKCACHENG, Tsang DawnCHEUNG, Ning MichelleHO, Sin ShingHUI, Kit Man GraceLAM, Cheung Kwan BrianLEE, Yeuk Ying SamanthaSO, Chi LongWONG, Chak ManCHENG, Yat HungCHU, Suk YiHO, Yau LeungKWAN, Wai Man GladysLEE, Yuk Ming SunnyLOW, Kai Ngai Kevin YvesSO, Ching YeeTSANG, Ho SzeAdmission to Fellowship ad eundem, FHKCA(IC)CHAN Kin WaiGOMERSALL, Charles DavidMichael IrwinChairman, Board of Censor113

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005Recent Meetings: Anaesthesia, Intensive Care & Pain managementLocal meetings 20052‐5 September, 2005 THE CHINESE SOCIETY OF ANAESTHESIOLOGISTS, ANNUAL MEETINGVenue: International Conference Centre of Dong Fang Hotel and China Hotel.Guangzhou. Contact: Email: csa8@china.com22 October, 2005 DIFFICULT AND ADVANCED AIRWAY MANAGEMENT WORKSHOPVenue: The Institute of Clinical Simulation, North District HospitalContact: Administrative Executive, HKCA, Phone: 2871 8833. Fax: 2814 1029, Email:office@hkca.edu.hk4 December, 2005 PAIN SEMINAR: THE ESSENTIALS OF CHRONIC PAIN MANAGEMENTVenue: Miramar Hotel, TSTContact: HKCA, Room 807, Hong Kong Academy of Medicine Building, 99 WongChuk Hang Road, Aberdeen, Hong Kong Phone: (852) 2871 8833. Fax: (852) 28141029, Email: office@hkca.edu.hk, website: www.hkca.edu.hk25 February, 2006 HKAM INTER‐COLLEGIATE CONGRESS 2006Theme: Disaster ManagementVenue: Hong Kong Convention and Exhibition CenterContact: HKAMOverseas Meetings 2005‐2006Gold Coast, QLDAUSTRALIA24‐27 September, 2005Adelaide, SAAUSTRALIA20‐23 October, 2005SINGAPORE24‐25 September, 2005HaroiVIETNAM23‐25 November, 200564 TH NATIONAL SCIENTIFIC CONGRESS OF THE AUSTRALIAN SOCIETYOF ANAESTHETISTSVenue: Gold Coast Convention and Exhibition Centre. Contact: OrganisersAustralia, PO Box 1237, Milton Qld 4064. Tel: 07 3369 7866 Fax: 07 3367 1471 Email:asa2005@orgaus.com.au Website: www.asa2005.org.au30 TH ANZICS/ACCCN ANNUAL SCIENTIFIC MEETING ON INTENSIVECAREContact: ANZICS, Level 3, 10 Ievers Terrace, Carlton VIC 3053. Tel: 03 9340 3400Fax: 03 9340 3499Email: asm@meetingplanners.com.au Website: www.anzics.com.au4 TH SCIENTIFIC MEETING OF THE ASIAN SOCIETY OF PAEDIATRICANAESTHESIOLOGISTSVenue: KK Womenʹs and Childrenʹs Hospital. Contact: Ms Jessie Tan. Secretariat,c/o Department of Paediatric Anaesthesia, KK Womenʹs and Childrenʹs Hospital,100 Bukit Timah Road, Singapore 229899. Tel: 65‐63941091 Fax: 65‐62912661 Email:jessiet@kkh.com.sg Website: http://www.aspa‐2000.com14 TH ASEAM CONGRESS OF ANAESTHESIOLOGISTSContact: Professor Nguyen Thu or Dr Cong Quyet Thang. AnesthesiologyDepartment, Viet Duc Hospital, 40 Trang Thi Street, Hanoi, Vietnam. Tel: +84 49286149 Fax: +84 4 8248308Email: nguyen_thugmhs@hmu.edu.jn or cqthang@fpt.vn114

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005New YorkUSA9‐13 December, 2005San Diego, USA14‐18 January, 2006QueenslandAUSTRALIA20‐24 October, 2006Adelaide, SAAUSTRALIA13‐17 May, 2006NEW YORK STATE SOCIETY OF ANESTHESIOLOGISTS 59 THPOSTGRADUATE ASSEMBLY IN ANESTHESIOLOGYVenue: New York Hilton Hotel, New York. Contact: NYSSA, Kurt G. Becker, 85Fifth Avenue, 8th Floor, New York, NY 10003. Tel: 1 212 867 7140 Fax: 1 212 8677153Email: kurt@nyssa‐pga.org Website: www.nyssa‐pga.org6 TH ANNUAL INTERNATIONAL MEETING ON MEDICAL SIMULATIONVenue: San Diego Sheraton. Contact: Society for Medical Simulation, PMB 300 223N. Guadalupe, Santa Fe, NM 8750 USA. Tel: 1 505 983 492 Fax: 1 505 983 5109Email: info@SocMedSim.org Website: www.socmedsim.org65 TH NATIONAL SCIENTIFIC CONGRESS OF THE AUSTRALIAN SOCIETYOF ANAESTHETISTSContact: Organisers Australia. PO Box 1237, Milton, Qld 4064. Tel: +61 (0)7 33710333 Fax: +61 (0)7 3371 05552006 ANZCA ASMTheme: All in a Day’s Work? Venue: Adelaide Convention Centre.Contact: Mr Christopher Boundy, South Australian Postgraduate MedicalEducation Association Inc (SAPMEA)Tel: 08 8274 6060 Fax: 08 8274 6000Email: admin@sapmea.asn.auWebsite: www.sapmea.asn.au/conventions/anzca/index.htmlPanel of Examiners with successful candidates in the Final Fellowship Examinations, April/May, 2005.The external examiners were Dr Hazel Adams (left three, front row) and Assoc. Professor Peter Klineberg(right four, front row).115

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Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005117

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005118

Bull HK Coll Anaesthesiol Volume 14, Number 2 July 2005The Hong Kong College of AnaesthesiologistsRoom 807, Hong Kong Academy of Medicine Building, 99 Wong Chuk Hang Road, Aberdeen, Hong KongPhone: (852) 2871 8833. Fax: (852) 2814 1029, Email: office@hkca.edu.hk, website: www.hkca.edu.hkOffice Bearers and Council (2003‐2005)PresidentTony GINVice PresidentsPo Tong CHUITheresa HUIHonorary SecretaryYu Fat CHOWHonorary TreasurerJoseph LUIAssistant SecretaryMatthew CHANAssistant TreasurerSimon CHANImmediate Past President Tsun Woon LEECouncil MembersJohn LIUTsz Yeung CHANPo Wah CHEUNGPhoon Ping CHENEdward HOChi Tim HUNGAnne KWANGavin JOYNTStaffAdministrative Executive Daniel TSOAssistantCherry WONGBoard of CensorMike Irwin (Chairman) YF Chow (Deputy Chair)Tony GinTom BuckleyDA Sudhaman Lilian LauTW LeePT ChuiJohn LiuKC LiCT HungBoard of Intensive Care MedicineGavin Joynt (Chair) Peggy Tan (Examination)HY So (Secretary) Anne Leung (TrainingKarl Youngofficer)YF ChowKW Au YeungEdward HoPW CheungTony GinGuidelines CommitteeAnne Kwan (Chair) PP ChenJoseph LuiTheresa HuiAgnes ChengBoard of ExaminationPT Chui (Chairman)Andrea OʹReganSL TsuiMike IrwinYF ChowKK Lam (Deputy Chair)Cindy AunCT HungTony GinPeggy TanBoard of AccreditationJohn Liu (Chairman) Mike IrwinAmy ChoJoseph LuiAndrea OʹRegan Anne KwanCT HungHY SoLilian LauTom BuckleyWallace Chiu Clement YuanPP ChenChandra RodrigoTony GinYF ChowBoard of EducationYF Chow (Chairman) CH Koo (Training officer)Tom Buckley PW CheungAndrew Chan Mike IrwinAndrea OʹRegan TW LeeTY ChanTony GinPT ChuiCK KooKK LamFormal Project Officer: KF NgMatthew Chan (Deputy officer)Board of Pain MedicinePP Chen (Chairman and Training officer)Steven Wong (Secretary) Anne Kwan (Accreditation)TW Lee (Examination) YF ChowS OnsiongCT HungSL TsuiKO SunTS SzeTony GinManpower CommitteeJohn Low (Chairman)Resuscitation CommitteeHY SoChandra RodrigoCT HungKM HoTY ChanOrganizer, Basic Science Course: CH KooOrganizers, Clinical Anaesthesiology Course: Douglas Fok and Eric SoChairman, The Institute of Clinical Simulation: KM Ho119