Normothermia Attenuates Cerebral Metabolic Distress In Patients With Aneurysmal Subarachnoid Hemorrhage And Refractory Fever
Posted Dec 04 2009 6:48am
A team of investigators from PENN MED (including WA Kofke, Department of Anesthesiology and Critical Care) recently investigated the effect of sustained fever (temperature greater than 38.3 deg C despite antipyretics) on the lactate/pyruvate ratio (LPR) of microdialisate samples obtained from brain tissue of patients who had acute subarachnoid hemorrhage (SAH).An increase in the LPR is considered a marker for increased anaerobic glycolysis, a sign of metabolic stress in brain.The authors defined an episode of metabolic crisis as an LPR greater than 40.Reducing body temperature with ice packs and an external cooling device reduced the mean LPR and reduced the percentage of LPR values in the metabolic crisis range.This was true whether or not ICP was elevated.The authors concluded that fever control is associated with reduced cerebral metabolic distress in patients with SAH irrespective of ICP (Oddo M et al: Induced normothermia attenuates cerebral metabolic distress in patients with aneurismal subarachnoid hemorrhage and refractory fever.Stroke 2009;40:1913-1916).
Dr. Fleisher (Chair, Department of Anesthesiology and Critical Care) points out that this paper has some interesting correlates with several papers showing increased cognitive dysfunction after cardiopulmonary bypass when the body temperature is greater than 37 degrees C: 1) Sahu B et al: Neurocognitive function in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass: The effect of two different rewarming strategies.J Cardiovasc Vasc Anesth 2009;23:14-21. 2) Grigone AM et al: The rewarming rate and increased peak temperature alter neurocognitive outcome after cardiac surgery.Anesth Analg 2002;94:4-10. 3) Grocon HP et al: Postoperative hyperthermia is associated with cognitive dysfunction after coronary artery bypass graft surgery.Stroke 2002;33:537-541