Postoperative bed header position after burr-hole drainage of chronic subdural haematoma: systematic review and meta-analysis of randomised controlled trials

Several studies have suggested the possible influence of postoperative bed header position on the risk of symptomatic recurrences and medical complications in patients who have been intervened due chronic subdural haematomas. Nevertheless, this hypothesis has not been assessed by a meta-analysis. All randomised controlled trials analysing symptomatic recurrence rates in patients who underwent burr-hole drainage of chronic subdural haematomas, describing postoperative bed header positioning, were included. The primary outcome was risk of recurrence and the secondary outcome were the risks of reoperation and medical complications. Results were presented as pooled relative risks, with 95% confidence intervals. A total of 4 controlled studies were included. Pooled relative risks were: symptomatic recurrences 0.51 ([95% CI: 0.22-1.16]; P=.11), reoperations, 1.07 ([95% CI: 0.42-2.69]; P=.89) and medical complications, 1.15 ([95% CI: 0.7-1.91]; P=.58). No statistically significant heterogeneity was found in any of the analyses. There were no differences regarding frequency of symptomatic recurrences, reoperations or medical complications in patients who were maintained in a flat position compared with those whose bed header was elevated during the postoperative course. Despite there being consistency between the results, there is a potential risk of bias; thus proscribing definitive recommendations until studies with higher methodological quality are available.