Maternal cardiac arrest in a tertiary care centre during 1989-2011: a case series.

PURPOSE: To review and report maternal and neonatal outcomes after cardiac arrest during pregnancy in a large tertiary care centre and to consider steps to improve the outcomes.

CLINICAL FEATURES: We performed a retrospective chart review of maternal cardiac arrest in the Mount Sinai Hospital, University of Toronto health records database for the period 1989-2011. Five cases were identified for an incidence of 1:24,883 deliveries (0.004%). Four of the five women were obese and older than 35 yr. Two women had pre-existing cardiac conditions, and one had placenta accrete. All three underwent perimortem Cesarean delivery (PMCD), but none of these procedures was done within the recommended time of the "four-minute rule." Two of the three women had repeated arrests and subsequently died. The other two women were in labour, received regional analgesia, and had assisted vaginal deliveries. Both of these patients survived, and all survivors (mothers and neonates) were neurologically intact. Four of five neonates survived. The etiology of the cardiac arrest was indeterminate in all five cases, although suspected amniotic fluid embolism was considered the most likely contributing factor in the majority of cases. Overall, the quality of the charting was inconsistent and incomplete.

CONCLUSIONS: This series of five cases highlights the challenges to meeting the rule of initiating PMCD within four minutes of maternal cardiac arrest onset. We suggest focusing on the quality of ongoing resuscitation efforts and early delivery as our experience shows that mother and neonate can survive beyond five minutes after arrest. Improved documentation and creation of a national database for these rare events should be considered.