Backgrounds and purpose: Body temperature in the acute phase of cerebrovascular disorders(CVDs) may influence the outcome. However, the natural course of body temperature after CVDs has not yet been clarified. The purpose of this study was to elucidate the natural courses of body temperature after CVDs.
Patients and methods: We retrospectively investigated 681 patients with CVDs(subarachnoid hemorrhage(SAH): 478, cerebral ischemia: 47, intracerebral hemorrhage(ICH): 156) who were admitted within 24 h after onset. The body temperature was measured with an electronic thermometer at the axilla on admission. The body temperatures of 73 patients with non-ruptured cerebral aneurysms on admission(admitted between 09:00 and 15:00) were used as normal control group.
Results: The body temperature in the control group was 36.49 +/- 0.45 degrees C. In comparison, the temperature in the SAH group was significantly lower(35.88 +/- 1.00 degrees C, n = 338, p < 0.001) when the patients were admitted within 4 h after onset, and significantly higher (36.80 +/- 0.85 degrees C, n = 140, p < 0.05) when they were admitted after 4 h and up to 24 h. There was a significant negative correlation between the severity of the SAH and body temperature within 4 h and a significant positive correlation beyond 4 h. Body temperature in the cerebral ishcemia group was significantly lower than in the control group(36.09 +/- 0.59 degrees C, n = 17, p < 0.05) when the patients were admitted within 2 h, but was close to that in the control group when they were admitted beyond 2 h and up to 24 h after onset (36.45 +/- 0.58 degrees C, n = 30). The falls of body temperature in the super-acute phase in the SAH and the cerebral ischemia groups were observed in patients admitted between 09:00 and 15:00. Although body temperature in the ICH group was slightly lower when the patients were admitted within 4 h and slightly higher when admitted beyond 4 h and up to 24 hours after onset, no significant differences were observed in comparison with the control group. In the super-acute phase of the cerebral ischemia and the ICH, body temperature tended to be lower in the patients with worse condition.
Conclusion: This study clearly demonstrated that body temperatures in patients with CVDs changed rapidly within 24 h after onset. Body temperature in the SAH group within 4 h and that in the cerebral ischemia group within 2 h after onset was significantly lower than in the control group. These temperature falls were not the products of circadian rhythm. The temperature in the SAH group beyond 4 h and up to 24 h after onset rose significantly. Comparison with normal controls and consideration of the circadian rhythm are important when studying changes of body temperature in patients with CVDs.