Research Reports - Barbiturates for acute traumatic brain injury
Cochrane Database Syst Rev. 2012 Dec 12;12
Roberts I, Sydenham E
BACKGROUND: Raised intracranial pressure (ICP) is an important complication of
severe brain injury, and is associated with high mortality. Barbiturates are
believed to reduce ICP by suppressing cerebral metabolism, thus reducing cerebral
metabolic demands and cerebral blood volume. However, barbiturates also reduce
blood pressure and may, therefore, adversely effect cerebral perfusion pressure.
OBJECTIVES: To assess the effects of barbiturates in reducing mortality,
disability and raised ICP in people with acute traumatic brain injury. To
quantify any side effects resulting from the use of barbiturates.
SEARCH METHODS: The following electronic databases were searched on 26 September
2012: CENTRAL (The Cochrane Library), MEDLINE (Ovid SP), PubMed, EMBASE (Ovid
SP), PsycINFO (Ovid SP), PsycEXTRA (Ovid SP), ISI Web of Science: Science
Citation Index and Conference Proceedings Citation Index-Science. Searching was
not restricted by date, language or publication status. We also searched the
reference lists of the included trials and review articles. We contacted
researchers for information on ongoing studies.
SELECTION CRITERIA: Randomised controlled trials of one or more of the
barbiturate class of drugs, where study participants had clinically diagnosed
acute traumatic brain injury of any severity.
DATA COLLECTION AND ANALYSIS: Two review authors screened the search results,
extracted data and assessed the risk of bias in the trials.
MAIN RESULTS: Data from seven trials involving 341 people are included in this
review.For barbiturates versus no barbiturate, the pooled risk ratio (RR) of
death from three trials was 1.09 (95% confidence interval (CI) 0.81 to 1.47).
Death or disability, measured using the Glasgow Outcome Scale was assessed in two
trials, the RR with barbiturates was 1.15 (95% CI 0.81 to 1.64). Two trials
examined the effect of barbiturate therapy on ICP. In one, a smaller proportion
of patients in the barbiturate group had uncontrolled ICP (68% versus 83%); the
RR for uncontrolled ICP was 0.81 (95% CI 0.62 to 1.06). In the other, mean ICP
was also lower in the barbiturate group. Barbiturate therapy results in an
increased occurrence of hypotension (RR 1.80; 95% CI 1.19 to 2.70). For every
four patients treated, one developed clinically significant hypotension. Mean
body temperature was significantly lower in the barbiturate group.In one study of
pentobarbital versus mannitol there was no difference in death between the two
study groups (RR 1.21; 95% CI 0.75 to 1.94). Pentobarbital was less effective
than mannitol for control of raised ICP (RR 1.75; 95% CI 1.05 to 2.92).In one
study the RR of death with pentobarbital versus thiopental was 1.78 (95% CI 1.03
to 3.08) in favour of thiopental. Fewer people had uncontrollable ICP with
thiopental (RR 1.64; 95% CI 1.03 to 2.60). There was no significant difference in
the effects of pentobarbital versus thiopental for death or disability, measured
using the Glasgow Outcome Scale (RR 1.31; 95% CI 0.88 to 1.94), or hypotension
(RR 0.95; 95% CI 0.81 to 1.12).
AUTHORS' CONCLUSIONS: There is no evidence that barbiturate therapy in patients
with acute severe head injury improves outcome. Barbiturate therapy results in a
fall in blood pressure in one in four patients. This hypotensive effect will
offset any ICP lowering effect on cerebral perfusion pressure.