2005 SAGES Abstracts

EMERGING TECHNOLOGY LUNCH POSTER ABSTRACTS
SAGES 2005
We have created “Ischemia Sensing Surgical Instruments” by
adapting and incorporating real-time pulse oximetry techniques
into the working surfaces of operative instruments.
These instruments provide real-time tissue oxygenation data.
In preliminary experiments, we monitored porcine hepatic
oxygenation during retraction while performing the Pringle
maneuver. Results demonstrated a correlation between our
measurements and the manipulation of the porta hepatis.
Future endeavors aim to develop a system for alerting the
operative team to impending tissue damage through sensory
substitution. In addition, we envision the system to extend
directly into robotically controlled instruments in order to
enhance the human - machine interface.
TP008
The Value of Video Intubation Techniques for Surgical
Residents, (S.R.)
Marshal Kaplan, MD, Denham Ward, MD, George Berci, MD *
Cedars Sinai Medical Center, Los Angeles/University of
Rochester, New York
In many institutions, SR?s must contend with emergency airway
situations where, unfortunately, an anesthesiologist is not
immediately available. This can be a challenge to a successful
intubation because of a lack of experience and technical difficulties.
Traditionally, a Macintosh blade on a laryngoscope handle
with a tiny battery powered globe is used to attempt intubation.
The authors have developed a standard Macintosh blade
and handle modified by the insertion of a TV camera into the
handle from which a miniature, (3mm) image-light bundle is
fitted in to the blade. An enlarged view is displayed on a monitor
screen. The entire unit, (light, camera control, screen, etc?),
is portable. Television techniques are well accepted in
Minimally Invasive Surgery to obtain a magnified appearance
of the anatomy. Should a second pair of hands be required,
e.g. to provide external laryngeal pressure, the Video display
is a great advantage as it allow both the intubator and the
assistant to follow the movements on the screen. This system
has been successfully used on several hundred patients by
anesthesiologists.
It is our hypothesis that if the SR?s are using a vastly
improved visual technique with appropriate education,
employing this mobile unit in the ICU?s or ER?s a greater safety
margin with fewer attempts can be expected.
It is definitely the method of choice in teaching. (A 7-minute
video strip will be included in the 10-minute presentation).
TP009
SMART TUTOR: A NOVEL ADAPTIVE SIMULATION ENVIRON-
MENT FOR TEACHING LAPAROSCOPIC MOTOR SKILLS, Thai
Pham MD, Lincoln Roland MD,Kenneth A Benson BA,Roger W
Webster PhD,Anthony G Gallagher PhD,Randy S Haluck MD,
Penn State College of Medicine, Hershey, PA; Soundshore
Medical Center, NYC, NY; Verefi Technologies, Hershey, PA;
Emory University, Atlanta, GA
Introduction: Optimal learning is best achieved in moderate
stress situations and without frustration. The Smart Tutor
Computing Algorithm (Verefi Technologies, Inc., Hershey, PA)
was developed and integrated into the RapidFire PC based
laparoscopic skills trainer (Verefi) to create real-time adjustments
in difficulty settings based on the users? performance.
The Smart Tutor algorithms aim to keep users of any level in
their optimal ?zone? of learning by minimizing frustration and
stress. The goal of this pilot study was to compare our first
generation RapidFire/Smart Tutor (RF/ST) to the Mentice
242 http://www.sages.org/
Minimally Invasive Surgery Trainer Virtual Reality (MIST VR)
system by examining levels of frustration in training of
novices, and measuring acquisition of laparoscopic motor
skills.
Methods: Three tasks from RapidFire were modified with two
different Smart Tutor algorithms (emphasizing speed or accuracy)
to create six tasks. For MIST VR, only the Acquire,
Transfer, and Traversal tasks were used. Expert performance
criteria (EPC) were established for RF/ST and MIST VR systems.
Ten medical students were randomized to train on each
system. For RF/ST, training was completed when subjects
achieved EPC in four of the six tasks in two consecutive trials.
For MIST VR, subjects were advanced from medium to master
level and then to completion of training when EPC were
achieved in two of the three MIST tasks for two consecutive
trials. Users were assessed by a standard pre- and post-training
laparoscopic paper cutting task. All subjects answered a
questionnaire regarding levels of frustration based on a five
point Likert scale. Data were compared using standard t-test.
Results: Data show that novice users had significant improvements
in their laparoscopic motors skill on both the RF/ST and
MIST VR. The average number of training trails required to
achieve EPC on RF/ST and MIST VR environments were 10±3
and 15±4 respectively (p=NS). A difference in subjective frustration
ratings was noted between RF/ST 2.0±0.8 and MIST VR
3.2±1.1 (p < 0.05).
Conclusion: Novices acquired laparoscopic skill as assessed on
their pre- and post-paper cutting scores after training on
RF/ST. Although not statistically significant, novice users were
achieving EPC with less number of trails with RF/ST. Of importance
is that RapidFire with Smart Tutor adaptive environment
is providing a less frustrating learning environment, which
may enhance laparoscopic skills acquisition.
TP010
VACUUM ASSISTED ABDOMINAL WALL LIFT FOR MINIMAL
ACCESS SUGERY (M.A.S). A PRELIMINARY PORCINE STUDY
TO EVALUATE SAFETY, EFFICACY AND FEASIBILITY,
Tehemton E Udwadia MD, Biten K Kathrani MS,Ulhas S Gadgil
PhD,William Bernie MD,V M Chariar MSc, Dept. of M.A.S. P. D.
Hinduja National Hospital, Regional R & D, Johnson &
Johnson Medical, Ethicon Endo Surgery Inc.
Objective: In a porcine model, to design a vacuum assisted
device for abdominal wall lift for Minimal Access Surgery
(MAS) with the intent to make MAS cost effective in developing
countries. Technology A transparent dome shaped device
was placed on the pigs abdomen and negative pressure was
applied between the device and the abdomen, which lifted the
abdominal wall firmly against the undersurface of the device.
The device was configured on mould casts made of the pig
abdomen insufflated to 14mmHg with CO2. The device had a
foam gasket in contact with the abdominal wall to maintain
vacuum and appropriately sited ports for trocar entry. It is
mandatory in this method to ENSURE free communication of
air from outside the device to the peritoneal space through a
sub-umbilical trocar placed by open entry passing through the
device. The air enters the peritoneal cavity pari passu with
vacuum creation and thereby preventing the viscera being lifted,
creating intra peritoneal space at ambient air pressure. Due
to ambient conditions gas leak is not a problem. Method The
study was divided into three groups; 1)in 12 animals to assess
the safety and feasibility of the method, 2)in 11 animals, in
addition to 1 above, performance of MAS procedures like lap.
chole., lap. salpingectomy, lap. assisted bowel resection and 3)
in 4 animals long term survival monitoring studies as in group
1 for 2 ? 8 days, after extreme and prolonged vacuum application.
Results a) Safe limits of vacuum to create and maintain
operative space were 50-150 mmHg for 2 hours. b) Continuous
monitoring of vital signs (ECG, HR, SPO2, ETCO2, resp rate,
rectal temp), biochemistry and histopathology- post procedure
confirmed device safety. c) Intraperitoneal work space by actual
measurement was comparable to CO2 insufflation.
Conclusion This study confirms the safety and efficacy of the
device. Every operating room has a suction machine which
can easily be adapted to create a vacuum for this lift, whereas
CO2 is not readily available in the developing world. This continuous
communication of air between the peritoneal cavity