Emergency Preservation and Resuscitation with Profound Hypothermia, Oxygen, and Glucose Allows Reliable Neurological Recovery after 3 h of Cardiac Arrest from Rapid Exsanguination in Dogs

Abstract

We have used a rapid induction of profound hypothermia (> 10°C) with delayed resuscitation using cardiopulmonary bypass (CPB) as a novel approach for resuscitation from exsanguination cardiac arrest (ExCA). We have defined this approach as emergency preservation and resuscitation (EPR). We observed that 2 h but not 3 h of preservation could be achieved with favorable outcome using ice-cold normal saline flush to induce profound hypothermia. We tested the hypothesis that adding energy substrates to saline during induction of EPR would allow intact recovery after 3 h CA. Dogs underwent rapid ExCA. Two minutes after CA, EPR was induced with arterial ice-cold flush. Four treatments ( n = 6/group) were defined by a flush solution with or without 2.5% glucose (G + or G–) and with either oxygen or nitrogen (O + or O–) rapidly targeting tympanic temperature of 8°C. At 3 h after CA onset, delayed resuscitation was initiated with CPB, followed by intensive care to 72 h. At 72 h, all dogs in the O + G + group regained consciousness, and the group had better neurological deficit scores and overall performance categories than the O—groups (both P < 0.05). In the O + G—group, four of the six dogs regained consciousness. All but one dog in the O—groups remained comatose. Brain histopathology in the O—G + was worse than the other three groups ( P < 0.05). We conclude that EPR induced with a flush solution containing oxygen and glucose allowed satisfactory recovery of neurological function after a 3 h of CA, suggesting benefit from substrate delivery during induction or maintenance of a profound hypothermic CA.