The effectiveness of early prophylactic hypothermia in adult patients with traumatic brain injury: A systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 32698987 · doi:10.1016/j.aucc.2020.05.005
What was done
A systematic review and meta-analysis was conducted across electronic databases (Cochrane CENTRAL, PubMed, MEDLINE, CINAHL, EMBASE, Web of Science, OpenGrey, ClinicalTrials.gov) through June 12, 2019. The authors included randomized controlled trials evaluating early prophylactic hypothermia (cooling initiated within 6 hours of injury) in adult patients with traumatic brain injury (TBI). Study quality was assessed using the Cochrane Risk of Bias Tool. Outcomes extracted included mortality, neurological outcomes, and complications across different cooling durations and rewarming rates.
What was found
Six randomized controlled trials with a total of 1,207 participants were included. Meta-analyses demonstrated no significant difference between early prophylactic hypothermia and controls for mortality (risk ratio = 1.11, 95% CI 0.90-1.37, P = 0.32) or favorable neurological outcomes (risk ratio = 1.03, 95% CI 0.91-1.16, P = 0.65). Subgroup analyses by hypothermia duration and rewarming rate also showed no significant benefits. Regarding safety, three studies found significantly higher complications in the hypothermia group, while three found no significant difference.
Why it matters
Despite animal studies suggesting neuroprotection from rapid cooling, this synthesis shows that prophylactic hypothermia within 6 hours of adult TBI does not improve survival or functional recovery and carries potential risks.
Limits
The total evidence base is limited to six randomized trials. The abstract does not provide pooled numerical risk estimates for adverse events, details on trial-level risk of bias, or breakdowns of injury severity.
Cited by
- supports Clinical studies of therapeutic hypothermia after traumatic brain injury have generally not shown a significant beneficial effect.