Fever burden and functional recovery after subarachnoid hemorrhage

Objective: Fever is associated with worse outcome after subarachnoid hemorrhage, but there are few prospective data to quantify this relationship. Methods: We prospectively enrolled consecutive aneurysmal or cryptogenic subarachnoid hemorrhage patients and recorded the highest core temperature each calendar day for Day 0 (the day of hemorrhage) through Day 13. Fever burden was defined as the daily highest core temperature minus 100.4°F, summed from admission through Day 13 (temperatures <100.4°F did not contribute to or subtract from fever burden). Outcomes were assessed at 14 days or at the time of hospital discharge with the National Institutes of Health Stroke Scale and modified Rankin Scale, and at 28 days and 3 months with the modified Rankin Scale. Improvement was analyzed with repeated measures analysis of variance. Results: We prospectively enrolled 94 patients. From 14 days to 28 days to 3 months, functional improvement was related to cumulative fever burden, admission neurological grade, aneurysm obliteration procedure, admission computed tomographic score, vasospasm, and external ventricular drainage. Good-grade patients had worse functional outcomes with increased fever burden, and poor-grade patients improved more over time when fever burden was higher (time by World Federation of Neurological Surgeons grade by fever burden interaction, P < 0.001). Patients with vasospasm (P = 0.04) and patients with higher computed tomographic scores (P = 0.002) had worse 14-day outcomes but improved more over time. Bacteremia and ventriculitis were uncommon (≤5%) and were not associated with higher fever burden. Conclusion: Cumulative fever burden was associated with worse outcomes in good-grade patients and potential late recovery in poor-grade patients. Effective fever control in febrile subarachnoid hemorrhage patients may improve functional outcomes and hasten recovery.