We commend the recent article by Rose et al entitled, “Challenging the 4- to 5-minute rule: from perimortem cesarean to resuscitative hysterotomy.” However, because the recent guideline from the American Heart Association, “Cardiac arrest in pregnancy: a scientific statement,” was not yet available for the authors to consider, we want to offer additional commentary.

We agree there is no optimal term for cesarean delivery during a maternal cardiac arrest. The term, perimortem cesarean delivery, has been used in the literature since 1986 and was selected for both the Society for Obstetric Anesthesiology and Perinatology Consensus Statement and the American Heart Association scientific statement for consistency. Additionally, the term used in the initial call for help must convey the potential for cesarean delivery.

Hysterotomy is generally defined as making an incision into the uterus and does not directly imply cesarean delivery. Terms such as emergent or resuscitative hysterotomy (as Rose et al suggest) could be confusing to multidisciplinary resuscitation teams. As a result, we strongly advocate continued use of the term perimortem cesarean delivery.

The novel suggestion of Rose et al is that a nonshockable rhythm such as pulseless electrical activity should prompt teams to proceed with immediate perimortem cesarean delivery, whereas a shockable rhythm such as ventricular fibrillation should prompt teams to defer perimortem cesarean delivery and prioritize defibrillation. Although we concur that defibrillation is a critical early intervention, we are not aware of supporting evidence that perimortem cesarean delivery as a therapeutic intervention is beneficial based on the cardiac rhythm, even anecdotally.

Whereas some exceptional teams may be able to differentiate between a reversible and nonreversible rhythm at an early time point, we believe that national and international bodies such as the Society for Obstetric Anesthesiology and Perinatology and the American Heart Association should produce guidelines written with a typical team’s response in mind. We believe the typical team, struggling with task saturation and significant cognitive loads, will further struggle with the additional burden of basing perimortem cesarean delivery on the presenting cardiac rhythm.

Even when preparations for perimortem cesarean delivery are started immediately, it is highly unlikely that the incision will occur within 5 minutes of maternal arrest. In simulation studies and retrospective clinical analyses, obstetric teams had great difficulty in performing perimortem cesarean delivery within 5 minutes, even when the arrest occurred in the hospital, was witnessed, and was performed at the site of arrest rather than an operating room. Einav et al found the presenting rhythm was not even identified in >20% of cases of perimortem cesarean delivery. If retrospective assessments are lacking the cardiac rhythm in more than 1 in 5 cases, can we expect obstetric staff to determine whether the rhythm was shockable under intense time pressure?

Lastly, several case reports of maternal cardiac arrest document transient cardiac rhythms that evolve rapidly. If the algorithm of Rose et al were adopted, such rapid changes could potentially distract even teams with expert rhythm recognition from performing high-quality chest compressions and delay perimortem cesarean delivery. Multiple studies have found that general knowledge of even basic interventions required for maternal resuscitation is poor. Because poor compliance rates exist for the current consensus recommendations, the adoption of the algorithm of Rose et al could further complicate a rare, dynamic, and complex event.

We believe that during maternal cardiac arrest, obstetric teams should follow current recommendations for basic life support/advanced cardiac life support with obstetric modifications as per the recent American Heart Association and Society for Obstetric Anesthesiology and Perinatology guidelines on maternal cardiac arrest and not base the decision to perform perimortem cesarean delivery on cardiac rhythm recognition.