Hibernation as a path to recovery—Is waiting worth the wait? When does improvement in neurologic function happen in survivors of cardiac arrest with an early poor exam?

Most cardiac arrest survivors remain unresponsive to verbal commands after return of spontaneous circulation (ROSC) with approximately two-thirds dying from neurologic causes, ¹ and over 80% of deaths mediated by withdrawal of life-sustaining therapy (WLST). ² Each year, in the United States alone, over 2,000 cardiac arrest survivors die from premature WLST (i.e., within the first 72 hours) due to perceived poor neurologic prognosis. By upholding such practice, we do not know who could have survived with an eventual favorable outcome. ³ Perceived poor neurologic outcome continues to strongly influence clinicians’ decisions, leading to self-fulfilling prophecy: one in four patients predicted to have a poor trajectory would have survived if given a chance, of whom one in six would have recovered to walk independently by hospital discharge. ⁴These numbers would be of much higher magnitude when we consider the potential for good outcomes in the subset of patients with a delayed neurologic recovery—i.e., in the months following index hospitalization for cardiac arrest. Longitudinal neurologic outcomes in those survivors who do not readily wake up during the early post-arrest course are scarce. This leads to difficulty recommending or justifying a prolonged observation period when a cardiac arrest survivor remains unconscious beyond this short timeframe, especially when there is not a clear and quantifiable devastating neurologic injury.