title: Therapeutic hypothermia for head injury.
abstract: BACKGROUND
  Induced hypothermia has been used in the treatment of head injury for many years. Encouraging results from small trials and laboratory studies led to renewed interest in the area and some larger trials.
  
  
  OBJECTIVE
  To estimate the effects of mild induced hypothermia in moderate and severe head injury on mortality, long-term functional outcome, complications, and short-term control of intracranial pressure (ICP).
  
  
  METHODS
  We searched the Injuries Group Specialised register (last searched in 2001), MEDLINE, EMBASE and the Cochrane Controlled Trials Register. We handsearched conference proceedings and checked reference lists of relevant articles, including a systematic review published in 2003.
  
  
  METHODS
  Randomised controlled trials of mild hypothermia to 34-35 masculine Celsius for at least 12 hours versus control (open or normothermia) in patients with any closed head injury requiring hospitalisation. Two reviewers independently assessed all trials.
  
  
  METHODS
  Data on death, Glasgow outcome scale, complications and ICP were sought and extracted, either from published material or by contacting the investigators. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each trial on an intention-to-treat basis. Quantitative synthesis of data on complications other than pneumonia or ICP was not attempted. Trials of immediate and deferred hypothermia were analysed separately.
  
  
  RESULTS
  We found 14 trials with 1094 participants. Active immediate hypothermia was associated with an OR for death of 0.80, (1061 patients, OR 0.80, 95% CI 0.61 to 1.04), and 0.75 for odds of being dead or severely disabled, (746 patients, OR 0.75, 95% CI 0.56 to 1.00). Hypothermia treatment was associated with a statistically significant increase in odds of pneumonia (281 patients, OR 1.95, 95% CI 1.18 to 3.23). The trial of deferred hypothermia (33 patients) reported a huge but not statistically significant reduction in the odds of death at six months, (OR 0.21, 95% CI 0.04 to 1.05). For death or severe disability, deferred hypothermia was associated with an OR of 0.10 (95% CI 0.01 to 1.00).
  
  
  CONCLUSIONS
  There is no evidence that hypothermia is beneficial in the treatment of head injury. The earlier, encouraging, trial results have not been repeated in larger trials. The reasons for this are unclear. Hypothermia increases the risk of pneumonia and has other potentially harmful side-effects. Therefore, it would seem inappropriate to use this intervention outside of controlled trials in subgroups of patients for whom there is good reason to think the treatment would be beneficial.
authors.affiliation: UK Cochrane Centre, NHS R&D Programme, Summertown Pavilion, Middle Way, Oxford, UK, OX2 7LG.
authors.forename: P
authors.initials: P
authors.lastname: Alderson
authors.forename: C
authors.initials: C
authors.lastname: Gadkary
authors.forename: D F
authors.initials: DF
authors.lastname: Signorini
mesh_terms: D006259:Craniocerebral Trauma / Q000401:mortality / Q000628:therapy*; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects; D016032:Randomized Controlled Trials as Topic