Seven RCTs, involving a total of 668 participants, were included in the review.
Four studies assessed the Glasgow Outcome Scale score. There was evidence of heterogeneity between the studies and no significant effect of hypothermia was found (OR 0.61, 95% CI: 0.26, 1.46, P=0.3)
Five studies assessed intracranial pressure, but only two had data available for the meta-analysis. The summary effect showed no significant effect of hypothermia (WMD -2.98, 95% CI: -7.58, 1.61, P=0.2), but there was evidence of heterogeneity.
Three studies, which were not significantly heterogeneous, reported on pneumonia and cardiac arrhythmia. There was no significant effect of hypothermia on either pneumonia (OR 2.05, 95% CI: 0.79, 5.32, P=0.14) or cardiac arrhythmia (OR 1.27, 95% CI: 0.38, 4.25, P=0.7).
Three studies assessed prothrombin time and partial thromboplastin time, of which only two provided data for statistical analysis. There was no evidence of heterogeneity. There was no significant effect of hypothermia on prothrombin time (WMD 0.02, 95% CI: -0.07, 0.10, P=0.7). However, the results for partial thromboplastin time (WMD 2.22, 95% CI: 1.73, 2.71, P<0.001) favoured normothermia over hypothermia.
No evidence of publication bias was found.