Surgical decompression for cerebral oedema in acute ischaemic stroke.

BACKGROUND: The high mortality that follows a large cerebral infarction is in part due to brain oedema. Oedema causes mass-effect with raised intracranial pressure and herniation. Medical therapies are used to reduce intracranial pressure but outcome is poor in spite of treatment. Decompressive surgical techniques that attempt to relieve high intracranial pressure due to oedema have been described, but their efficacy in reducing case fatality and disability is uncertain.
OBJECTIVES: To compare medical therapy plus decompressive surgery with medical therapy alone on the outcomes death and 'death or dependency' in patients with an acute ischaemic stroke complicated by clinical and radiologically confirmed cerebral oedema. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (4 October 2001). In addition, we searched the following electronic databases: the Cochrane Controlled Trials Register (Cochrane Library, issue 3, 2001), MEDLINE (1966 - April 2002), EMBASE (1980 - April 2002), and SCISEARCH (to April 2002). We also searched the reference lists of all relevant articles retrieved and contacted individual investigators and experts in the field. SELECTION CRITERIA: Randomised controlled studies comparing the outcome of treatment with decompressive surgical intervention with treatment not involving surgery. We aimed to include only those studies with low or moderate risk of bias. DATA COLLECTION AND ANALYSIS: Titles retrieved by searching were assessed for relevance by one author. Data were extracted independently by two authors with discussion to resolve differences. Relevant sub-group analyses were planned and we planned to calculate Peto odds ratios with 95% confidence intervals. MAIN
RESULTS: Over 9000 citations were retrieved and inspected for relevance. We identified no randomised-controlled trials to include in a meta-analysis. Five observational studies reporting comparative data were found along with a number of small series and single case reports. Two ongoing randomised-controlled trials were identified. REVIEWER'S
CONCLUSIONS: There is no evidence from randomised-controlled trials to support the use of decompressive surgery for the treatment of cerebral oedema in acute ischaemic stroke. Evidence from randomised-controlled trials is needed to accurately assess the effect of decompressive surgery.