Moderate hypothermia treatment in adult patients with severe traumatic brain injury: a meta-analysis

To evaluate the effect of moderate hypothermia treatment (MHT) in severe traumatic brain injury (sTBI) compared to normothermia management.

PubMed, Medline, Springer, Elsevier Science Direct, Cochrane Library and Google scholar were searched up to December 2012. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) for the mortality and clinical neurological outcome of the adult patients with sTBI were collected and calculated in a fixed-effects model or a random-effects model. Summary effect estimates were stratified by study design and ethnicity. Egger's regression asymmetry tests were utilized for detecting the publication bias.

The overall estimates showed that MHT could reduce the mortality (hypothermia vs. normothermia, RR = 0.86, 95% CI = 0.73-1.01, p = 0.06) and unfavourable clinical neurological outcomes (RR = 1.21, 95% CI = 0.95-1.53, p = 0.12) for traumatic brain injured patients without statistical significance. Moreover, the further stratification sub-group analysis indicated that MHT presented a significant reduction (RR = 0.60, 95% CI = 0.44-0.83, p = 0.002) of mortality compared to the normothermia management in an Asian population. Surprisingly, American patients treated with moderate hypothermia showed an increasing mortality (RR = 1.07, 95% CI = 0.83-1.39, p = 0.61).

MHT may be effective in reducing death and unfavourable clinical neurological outcomes, but this finding is not statistically significant, except for decreasing the mortality in Asian patients.