Hypothermia in Neurocritical Care

Hypothermia has long been recognized as an effective therapy for acute neurologic injury. Recent advances in bedside technology and greater understanding of thermoregulatory mechanisms have made this therapy readily available at the bedside. Critical care management of the hypothermic patient can be divided into 3 phases: induction, maintenance, and rewarming. Each phase has known complications that require careful monitoring. At present, hypothermia has only been shown to be an effective neuroprotective therapy in cardiac arrest survivors. The primary use of hypothermia in the neurocritical care unit is to treat increased intracranial pressure.

Key points

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The ability of hypothermia to protect tissue from ischemic damage is primarily related to its effects on metabolism, with oxygen use decreasing linearly by 5% to 9% per degree centigrade.
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Therapeutic hypothermia applied within hours of injury designed as a neuroprotective strategy and delayed TH designed to mitigate the effect of increased intracranial pressure (ICP).
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At present, hypothermia has only been shown to be an effective therapy for cardiac arrest and reducing ICP.
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Shivering and immune suppression are the most significant concerns during the maintenance phase of cooling.
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Rewarming is the most dangerous phase of cooling because of the increased risk for rebound cerebral edema and increased ICP.