Young patients may survive accidental deep hypothermia with prolonged asystolic circulatory arrest because of protective effects of cold.

An 8-year-old boy fell through pond ice and was submerged for ≥147 minutes. Nadir peripheral body temperature was 7 °C (45 °F). After rewarming with extracorporeal membrane oxygenation, prolonged hospitalization, and neurorehabilitation, the child recovered.

This is the longest submersion time and nadir body temperature survived in medical literature. Findings inform and extend time and temperature limits from which human life may be rescued from asystolic hypothermia. This case raises clinical, scientific, and ethical considerations for drowning rescue, organ preservation, and neurologic recovery after prolonged total body ischemia.

Resuscitation and extracorporeal rewarming to save a child may be considered for upward of 2.5 hours of asystolic hypothermia with temperature as low as 7 °C (45 °F). If neurologic recovery is not observed, end-organ preservation on extracorporeal membrane oxygenation may bridge to pediatric organ donation.