Critically evaluate the role of induced hypothermia in the management of critically ill patients in Intensive Care.

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College Answer

Rapidly expanding area, answer needs covering of various areas.

Evidence to support use: comatose survivors after cardiac arrest had improved neurological survival (recent PRCT NEJM X 2); controversial/equivocal for severe head injuries (GCS 3-8), certainly demonstrated to decrease ICP; early evidence to support use in stroke and perhaps myocardial infarction; anecdotal evidence to support cooling to at least normothermia (eg. management of malignant hyperpyrexia); experimental for ARDS; use as adjuvant to minimise cerebral insult (prophylaxis) in the operating theatre during cardiac surgery (deep hypothermic circulatory arrest) and some neurosurgical procedures.

Technique: need to define temperature (eg. 32-33 degrees C), method to cool (blankets, surface cooling, intravenous device), and duration of therapy (eg. 12-24 hours or days).

Potential problems: immune suppression (increased infections), risks bleeding, vasoconstriction, shivering (necessitating neuromuscular paralysis and adverse effects of immobility).

Discussion

This question is identical to Question 20 from the second paper of 2006.