European Resuscitation Council Guidelines for Resuscitation ... - CPR

18 de 0ctubre de 2010 www.elsuapdetodos.com1422 J. Soar et al. / Resuscitation 81 (2010) 1400–1433• psychiatric disorders;• hypertensive disorders of pregnancy;• sepsis;• haemorrhage;• amniotic-fluid embolism;• ectopic pregnancy.Pregnant women can also sustain cardiac arrest from the samecauses as women of the same age group.Key interventions to prevent cardiac arrest• Start basic life support according to standard guidelines. Ensuregood quality chest compressions with minimal interruptions.• Manually displace the uterus to the left to remove caval compression.• Add left lateral tilt if this is feasible – the optimal angle of tilt isunknown. Aim for between 15 ◦ and 30 ◦ . Even a small amount oftilt may be better than no tilt. The angle of tilt used needs to allowgood quality chest compressions and if needed allow Caesareandelivery of the fetus.• Start preparing for emergency Caesarean section (see below) –the fetus will need to be delivered if initial resuscitation effortsfail.In an emergency, use an ABCDE approach. Many cardiovascularproblems associated with pregnancy are caused by aortocavalcompression. Treat a distressed or compromised pregnant patientas follows:• Place the patient in the left lateral position or manually and gentlydisplace the uterus to the left.• Give high-flow oxygen guided by pulse oximetry.• Give a fluid bolus if there is hypotension or evidence of hyovolaemia.• Immediately re-evaluate the need for any drugs being given.• Seek expert help early. Obstetric and neonatal specialists shouldbe involved early in the resuscitation.• Identify and treat the underlying cause.Modifications to BLS guidelines for cardiac arrestAfter 20 weeks gestation, the pregnant woman’s uterus canpress down against the inferior vena cava and the aorta, impedingvenous return and cardiac output. Uterine obstruction of venousreturn can cause pre-arrest hypotension or shock and, in the criticallyill patient, may precipitate arrest. 481,482 After cardiac arrest,the compromise in venous return and cardiac output by the graviduterus limits the effectiveness of chest compressions.Non-arrest studies show that left lateral tilt improves maternalblood pressure, cardiac output and stroke volume 483–485 andimproves fetal oxygenation and heart rate. 486–488 Two studiesfound no improvement in maternal or fetal variables with 10–20 ◦left lateral tilt. 489,490 One study found more aortic compression at15 ◦ left lateral tilt when compared with a full left lateral tilt. 484Aortic compression has been found to persist at over 30 ◦ of tilt. 491Two non-arrest studies show that manual left uterine displacementwith the patient supine is as good as or better than left lateral tiltin relieving aortocaval compression, as assessed by the incidenceof hypotension and ephedrine use. 492,493 Non-cardiac arrest datashow that the gravid uterus can be shifted away from the cavain most cases by placing the patient in 15 ◦ of left lateral decubitusposition. 494 The value of relieving aortic or caval compressionduring CPR is, however, unknown.Unless the pregnant victim is on a tilting operating table, leftlateral tilt is not easy to perform whilst maintaining good qualitychest compressions. A variety of methods to achieve a left lateral tilthave been described including placing the victim on the rescuersknees 495 , pillows or blankets, and the Cardiff wedge 496 althoughtheir efficacy in actual cardiac arrests is unknown. Even when atilting table is used, the angle of tilt is often overestimated. 497 In amanikin study, the ability to provide effective chest compressionsdecreased as the angle of left lateral tilt increased and that at anangle of greater than 30 ◦ the manikin tended to roll. 496The key steps for BLS in a pregnant patient are:• Call for expert help early (including an obstetrician and neonatologist).Modifications to advanced life supportThere is a greater potential for gastro-oesophageal sphincterinsufficiency and risk of pulmonary aspiration of gastric contents.Early tracheal intubation with correctly applied cricoid pressuredecreases this risk. Tracheal intubation will make ventilation of thelungs easier in the presence of increased intra-abdominal pressure.A tracheal tube 0.5–1 mm internal diameter (ID) smaller thanthat used for a non-pregnant woman of similar size may be necessarybecause of maternal airway narrowing from oedema andswelling. 498 One study documented that the upper airways in thethird trimester of pregnancy are narrower compared with theirpostpartum state and to non-pregnant controls. 499 Tracheal intubationmay be more difficult in the pregnant patient. 500 Expert help,a failed intubation drill and the use of alternative airway devicesmay be needed (see Section 4). 24a,501There is no change in transthoracic impedance during pregnancy,suggesting that standard shock energies for defibrillationattempts should be used in pregnant patients. 502 There is no evidencethat shocks from a direct current defibrillator have adverseeffects on the fetal heart. Left lateral tilt and large breasts willmake it difficult to place an apical defibrillator paddle. Adhesivedefibrillator pads are preferable to paddles in pregnancy.Reversible causesRescuers should attempt to identify common and reversiblecauses of cardiac arrest in pregnancy during resuscitation attempts.The 4 Hs and 4 Ts approach helps identify all the common causes ofcardiac arrest in pregnancy. Pregnant patients are at risk of all theother causes of cardiac arrest for their age group (e.g., anaphylaxis,drug overdose, trauma). Consider the use of abdominal ultrasoundby a skilled operator to detect pregnancy and possible causes duringcardiac arrest in pregnancy; however, do not delay other treatments.Specific causes of cardiac arrest in pregnancy include thefollowing.www.elsuapdetodos.comHaemorrhageLife-threatening haemorrhage can occur both antenatally andpostnatally. Postpartum haemorrhage is the commonest singlecause of maternal death worldwide and is estimated to cause onematernal death every 7 min. 503 Associations include ectopic pregnancy,placental abruption, placenta praevia, placenta accreta, anduterine rupture. 480 A massive haemorrhage protocol must be availablein all units and should be updated and rehearsed regularly inconjunction with the blood bank. Women at high risk of bleedingshould be delivered in centres with facilities for blood transfusion,intensive care and other interventions, and plans should bemade in advance for their management. Treatment is based on anABCDE approach. The key step is to stop the bleeding. Consider thefollowing: