Chapter 167: Perimortem Cesarean Section (Perimortem Cesarean Delivery)

INTRODUCTION

The term “perimortem cesarean delivery” (PMCD) was introduced in 1986 to describe a cesarean section performed during cardiopulmonary resuscitation (CPR) of the mother and initiated within the first 4 minutes following maternal arrest.¹ The goals of this procedure are to improve the effectiveness of maternal resuscitation as well as to increase the chances of fetal survival.^2,3 For more than two decades, the PMCD has been included as part of the algorithm for management of cardiac arrest in pregnant patients.^4-7

The incidence of cardiac arrest during pregnancy is estimated to be about 1 in 30,000 pregnancies.^8,9 According to a review of reported PMCDs from 1985 to 2004, the most frequent causes are anesthesia, cardiogenic, eclampsia, emboli (e.g., amniotic fluid and air), intracranial hemorrhage, magnesium overdose, sepsis, spontaneous uterine rupture, and trauma.²

Trauma is the leading cause of death in women of reproductive age and accounts for 25% to 50% of maternal morbidity. Major maternal injury is associated with a fetal loss rate of 45% to 50%. The primary goal in the management of the severely injured pregnant patient is maternal assessment and stabilization. Prompt attention to the needs of the gravid patient can save the life of both the fetus and the mother. There are occasions when emergent cesarean delivery is the intervention most likely to save the life of the mother, the fetus, or both.

This procedure is best performed by a qualified Surgeon in the Operating Room. However, in the case of maternal arrest out of hospital or in the Emergency Department, valuable minutes should not be wasted transferring the patient to an Operating Room. Rather, the Emergency Physician should proceed with PMCD with the goal of fetal delivery by minute 5 after maternal arrest. It may also be performed for imminent maternal demise. PMCD is a key procedure that all Emergency Physicians need to be able to perform in the rare instance that it is required.

There are two basic conditions that must be met when considering PMCD. First, confirm that the uterine fundus reaches the mother’s umbilicus (or higher) correlating with a gestational age of 20 weeks (or more). This is the point at which aortocaval compression by the uterus has a significant impact on maternal hemodynamics. Second, verify that the mother is pulseless and that noninvasive manual displacement of the uterus to her left side does not lead to return of spontaneous circulation (ROSC). Proceed quickly to PMCD unless there is another obvious intervention that is likely to lead to maternal ROSC.

ANATOMY AND PATHOPHYSIOLOGY

Important physiologic changes during pregnancy should be kept in mind in the event of maternal cardiac arrest.¹⁰ Cardiac output, blood volume, and heart rate all increase during pregnancy. Pulmonary and systemic vascular resistance decreases. Uteroplacental blood flow increases with the uterus receiving ...