Does bed rest after cervical or lumbar puncture prevent headache? A systematic review and meta-analysis

Abstract

Background: Headache after cervical or lumbar puncture has long been attributed to early mobilization; however, there is little evidence for this. We performed a systematic literature review and meta-analysis of randomized controlled trials to assess whether longer bed rest is better than immediate mobilization or short bed rest in preventing headache.

Methods: We searched EMBASE (1988 to March 2001), MEDLINE (1966 to May 2001), Pascal Biomed (1996 to February 2001), Current Contents (1997 to September 1999), PsycINFO (1966 to May 2001), the Cochrane Controlled Trial Register (last search May 15, 2001), textbooks and references of the papers selected. Studies were eligible if patients underwent cervical or lumbar puncture for any reason and were randomly assigned to either a long or a short period of bed rest. Data were abstracted independently by 2 investigators to a predefined form.

Results: We found 16 randomized controlled trials involving 1083 patients assigned to immediate mobilization or a short period of bed rest (up to 8 hours) and 1128 patients assigned to a longer period of bed rest (0.5 to 24 hours). Puncture was performed for anesthesia (5 trials), myelography (6 trials) and diagnostic reasons (5 trials). None of the trials showed that longer bed rest was superior to immediate mobilization or short bed rest for preventing headache after puncture. When pooling the results of the trials in the myelography group and the diagnostic group, the relative risks of headache after puncture were 0.93 (95% confidence interval [CI] 0.81-1.08) and 0.97 (95% CI 0.79-1.19) respectively. We did not pool the results from the trials in the anesthesia group because of clinical heterogeneity, but shorter bed rest appeared to be superior.

Interpretation: There was no evidence that longer bed rest after cervical or lumbar puncture was better than immediate mobilization or short bed rest in reducing the incidence of headache.

Fig. 1: Selection process of randomized controlled trials for meta-analysis.

Fig. 2: Absolute and relative effect size for short bed rest versus long bed rest to prevent headache after lumbar or cervical puncture. (An expanded version of the figure, with relative risks and 95% confidence intervals, is available online at www.cma.ca/cmaj/vol-165/issue-10/pdf/thofig2.pdf).

Fig. 3: Funnel plot, to assess whether there is evidence of publication bias. The standard normal deviate of the relative risk (natural logarithm of the relative risk divided by its standard error [SE]) is plotted against the estimate's precision (inverse of the SE).