Most anesthesiologists have received Advanced Cardiac Life Support (ACLS) certification. Does that mean we know how to resuscitate a parturient following cardiac arrest? American Heart Association (AHA) ACLS courses generally don’t spend much time, if any, teaching obstetric-specific interventions.
Dr. Brendan Carvalho, Department of Anesthesia, Stanford University School of Medicine, Stanford, California, and colleagues, on behalf of the Society for Obstetric Anesthesia and Perinatology, have developed a consensus statement designed to expand AHA 2010 guidelines to focus on maternal resuscitation. This statement appears in this month’s edition of Anesthesia & Analgesia in the article titled “The Society for Obstetric Anesthesia and Perinatology Consensus Statement on the Management of Cardiac Arrest in Pregnancy.”
As the authors note, maternal arrests are rare. As a result, evidence supporting proposed clinical interventions are limited. When a maternal arrest is initiated, both an obstetric-oriented code should be activated and a neonatal team contacted. Compressions should be hard (about 5-cm depth), fast (100 compressions/minute), and not be interrupted. When checking for a shockable rhythm, pauses should be < 5 seconds. If the patient’s trachea is intubated, chest compressions should continue. If not, 30 chest compressions should be followed by 2 breaths with the intent of providing 100 compressions per minute. If the patient is in the third trimester, the hand used for compression should be placed 2-3 cm higher than for an individual who is not pregnant. If the uterus is palpable or visible at or above the umbilicus, left uterine displacement (LUD) should be achieved in order to avoid vena cava compression. During chest compression, ideally the parturient should be placed supine on a firm surface, with manual LUD performed using two hands from the left side of the patient, pulling leftward and upward.
In most obstetric situations, an AED device is the most practical for rapid defibrillation. If during CPR a fetal scalp electrode is also being used to monitor fetal heart rate, it can be moved before the shock and in preparation for cesarean delivery. During an arrest, fetal monitoring should not guide management.
Airway management, of course, is important. Certainly pregnant patients are at risk for aspiration, yet during this time, oxygenation and ventilation are more important than aspiration prevention. In fact, cricoid pressure may not effectively prevent aspiration and may even impede ventilation and laryngoscopy.
If cardiac arrest is occurring during massive hemorrhage, multiple large-gauge catheters may be needed. Warm fluids, initiate a massive transfusion protocol, and contact gynecologic oncologists, vascular surgeons, and/or trauma surgeons. In anticipation of difficult venous access, institutions should develop an algorithm; intraosseous and/or central venous access above the diaphragm should be considered. The use of resuscitation and other drugs should follow AHA guidelines. Though the volume of distribution and clearance of drugs are different during pregnancy, those differences are irrelevant if there’s little or no cardiac output. If cardiac arrest is likely secondary to local anesthesia administration, lipid emulsion therapy should be considered.
If the mother has cardiac arrest and is not responsive to CPR, the fetus should be rapidly delivered and CPR should continue. Incision should occur within 4 minutes and fetal delivery should occur within five minutes after the start of cardiac arrest. Indeed, there have been many reports of hemodynamic improvement after delivery.
This is an extremely well-written article with thorough references, appropriate figures, and practical suggestions for institutions. The multi-disciplinary nature of the report adds to its value and will hopefully lead to its acceptance by other specialties. What is provided here is a brief summary and the reader is encouraged to read the article in its entirety. The article should also be readily available in the labor and delivery suite, so that the guidelines can be regularly reviewed by the anesthesia, nursing, and obstetric care teams.