How many minutes after cardiac arrest with no return of spontaneous circulation (ROSC) should a peri-mortem cesarean delivery be performed on a pregnant woman, likely in her second or third trimester?

Perimortem Cesarean Delivery Timing in Maternal Cardiac Arrest

Perimortem cesarean delivery should be started at 4 minutes after the onset of maternal cardiac arrest if there is no return of spontaneous circulation (ROSC), with the goal of achieving delivery by 5 minutes. 1, 2

The Critical 4-Minute Decision Point

The procedure must be initiated at the 4-minute mark—not completed, but started—to achieve delivery by 5 minutes, which represents the optimal window for both maternal and fetal survival. 1, 2

• The 2020 American Heart Association Guidelines explicitly state that perimortem cesarean delivery should be considered at 4 minutes after onset of maternal cardiac arrest if there is no ROSC. 1
• This timing applies to any pregnant patient with a fundus at or above the umbilicus (approximately ≥20 weeks gestation), as aortocaval compression significantly impairs resuscitation efforts at this stage. 2
• The emergency cesarean section team should be activated immediately at the onset of maternal cardiac arrest in any woman with an obviously gravid uterus—do not wait until the 4-minute mark to mobilize resources. 1

Why This Timing Prioritizes Maternal Survival

The primary goal of perimortem cesarean delivery is maternal resuscitation, not just fetal salvage. 2, 3 The procedure relieves aortocaval compression, which dramatically improves cardiac output and coronary perfusion pressure. 2

• In a case series of 38 perimortem cesarean deliveries, 12 of 20 women achieved return of spontaneous circulation immediately after delivery. 1, 2
• No cases reported worsening of maternal status after cesarean delivery. 1
• Maternal survival has been documented with perimortem cesarean section performed up to 15 minutes after cardiac arrest onset, though outcomes are significantly better with earlier intervention. 1
• In a UK cohort study, the median time from collapse to perimortem cesarean delivery was 3 minutes in women who survived compared with 12 minutes in nonsurvivors. 1

Fetal Outcomes Support the 5-Minute Window

• Best fetal survival occurs when delivery happens within 5 minutes after maternal cardiac arrest, particularly at gestational ages >24-25 weeks. 1, 2, 3
• In the UK cohort study, 24 of 25 infants survived when perimortem cesarean delivery occurred within 5 minutes after maternal cardiac arrest, compared with only 7 of 10 infants when it occurred more than 5 minutes after arrest. 1
• At gestational ages ≥30 weeks, infant survival has been documented even when delivery occurred after 5 minutes from onset of maternal cardiac arrest. 1, 3
• Neonatal survival has been documented with perimortem cesarean delivery performed up to 30 minutes after the onset of maternal cardiac arrest, though neurological outcomes are significantly worse with delays. 1

Practical Implementation: What to Do at Each Time Point

At time of cardiac arrest recognition:

• Designate a timekeeper to call out times at 1-minute intervals. 1, 2
• Activate the emergency cesarean section team immediately. 1
• Begin high-quality CPR with manual left uterine displacement. 1
• Prepare for bedside cesarean delivery while CPR continues—do not wait. 1, 2

At 4 minutes without ROSC:

• START the perimortem cesarean delivery at the bedside. 1, 2
• Moving to an operating room should only be considered if it can be accomplished in 1-2 minutes or less; otherwise, perform the procedure at the site of arrest. 1, 3
• Only a scalpel is required to begin—do not delay for surgical equipment or ideal conditions. 2

Critical Pitfalls to Avoid

• Do not wait the full 5 minutes to begin the procedure—you must start at 4 minutes to achieve delivery by 5 minutes. 1, 2
• Do not delay for transport to the operating room—the procedure should be performed at the site of arrest in most cases. 1
• Do not assume early ROSC eliminates the need for perimortem cesarean delivery—aortocaval compression persists even after ROSC and can precipitate re-arrest. 2, 4
• Do not hesitate in cases of obvious nonsurvivable maternal injury—if the maternal prognosis is grave and resuscitative efforts appear futile, moving straight to emergency cesarean section may be appropriate, especially if the fetus is viable. 1, 3

Evidence Quality and Real-World Performance

The expert recommendation for timing at less than 5 minutes remains an important goal, though it is rarely achieved in practice. 1 In a systematic review, the time to delivery was within 4 minutes in only 4 of 57 (7%) reported cases. 1 However, the median time from maternal cardiac arrest to delivery was 9 minutes in surviving mothers versus 20 minutes in nonsurviving mothers, demonstrating that earlier intervention correlates with better outcomes even when the 5-minute goal is not met. 1