Hypothermia for traumatic brain injury.
Level 1 - systematic review of randomized trials
Systematic review of randomized controlled trials
PubMed 28933514 · doi:10.1002/14651858.CD001048.pub5
What was done
This Cochrane systematic review searched multiple databases through March 2016 (updated June 2017) for randomized controlled trials comparing mild hypothermia (≤35 °C for ≥12 hours, maintained for ≥24 hours) with normothermia (36.5–38 °C) in hospitalized adults and children with closed traumatic brain injury. The authors evaluated mortality, unfavorable functional outcome (Glasgow Outcome Scale: death, vegetative state, or severe disability), and pneumonia, grading evidence certainty using GRADE.
What was found
Across 37 trials (3,110 participants), 33 reported mortality, 31 reported unfavorable outcomes, and 14 reported pneumonia. Results showed severe inconsistency with conflicting directions of effect across studies, which persisted after subgrouping by hypothermia duration and follow-up length. Consequently, no pooled numerical meta-analysis was performed. Evidence quality was rated very low for mortality and unfavorable outcomes, and low for pneumonia.
Why it matters
Despite numerous trials, there is no high-quality evidence that therapeutic hypothermia improves survival or functional outcomes in traumatic brain injury.
Limits
Included studies were generally poorly reported, preventing adequate risk-of-bias assessment. Pronounced clinical and methodological heterogeneity precluded quantitative pooling, and potential sources of bias or inconsistency were not evaluated through detailed subgroup or sensitivity analyses.
Cited by
- supports Clinical studies of therapeutic hypothermia after traumatic brain injury have generally not shown a significant beneficial effect.