Impact of induced normothermia on outcome after subarachnoid hemorrhage: a case-control study

Abstract

Objective: Fever during the first week after subarachnoid hemorrhage (SAH) is associated with poor outcome; however, eliminating fever has not been shown to improve outcome. We sought to explore the potential impact of induced normothermia using advanced fever control (AFC) methods on outcome after SAH.

Methods: We identified 40 consecutive febrile patients enrolled in the Columbia University SAH Outcomes Project between 2003 and 2005 who underwent AFC (37 degrees C) with a surface cooling device during the first 14 days after SAH and randomly matched by age, Hunt and Hess grade, and SAH sum score to 80 SAH patients who underwent conventional fever control between 1996 and 2004. Average daily fever burden was calculated as the time and extent (degrees C x hours) above 37 degrees C. Poor outcome was defined as death or moderate to severe disability (modified Rankin Scale score of 4 or higher). A multivariate analysis was performed to identify factors associated with poor outcome 12 months after SAH.

Results: The fever burden was lower over 14 days in the AFC patients as compared with the patients receiving conventional fever control (P < .001). AFC patients had higher rates of hyperglycemia (P < .01) and arrhythmias (P = .02). Higher admission Hunt and Hess grade on admission and the development of pneumonia (P = .02) were associated with an increased risk for poor outcome at 12 months (P = .04), whereas AFC was associated with a reduced risk (P = .004) after adjusting for age, arrhythmia, and anemia.

Conclusion: Elimination of fever with AFC may be associated with improved outcome after SAH. A prospective randomized trial of AFC vs conventional fever control is warranted.