Anaesthesia for hip fracture surgery in adults.

BACKGROUND: The majority of hip fracture patients are treated surgically, requiring anaesthesia.
OBJECTIVES: To compare different types of anaesthesia for surgical repair of hip fractures (proximal femoral fractures) in adults. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group specialised register (December 2000), MEDLINE (1996 to December Week 4 2000) and reference lists of relevant articles. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing different methods of anaesthesia for hip fracture surgery in skeletally mature persons. The primary focus of this review was the comparison of regional (spinal or epidural) anaesthesia versus general anaesthesia; this has been expanded to include other comparisons. The use of nerve blocks pre-operatively or in conjunction with general anaesthesia is evaluated in another review. The primary outcome was mortality. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality, using a nine item scale, and extracted data. Results were pooled wherever appropriate and possible. MAIN
RESULTS: Seventeen trials, involving 2305 patients, comparing regional anaesthesia with general anaesthesia were included. All trials had methodological flaws. Pooled results from eight trials showed regional anaesthesia to be associated with a decreased mortality at one month (53/781(6.8%) versus 78/826(9.4%)); this was of borderline statistical significance (relative risk (RR) 0.72, 95% confidence interval (CI) 0.51 to 1.00). The results from six trials for three month mortality were not statistically significant, although the confidence interval does not exclude the possibility of a clinically relevant reduction (86/726 (11.8%) versus 98/765 (12.8%), RR 0.92, 95% CI 0.71 to 1.21). The reduced numbers of patients at one year, coming exclusively from two studies, preclude any useful conclusions for long term mortality (80/354 (22.6%) versus 78/372 (21.0%), RR 1.07, 95% CI 0.82 to 1.41). Regional anaesthesia was associated with a tendency to a longer operation (weighted mean difference 4.8 minutes, 95% CI 1.1 to 8.6 minutes), and a reduced risk of deep venous thrombosis (39/129 (30%) versus 61/37(76%); RR 0.64, 95% CI 0.48 to 0.86), although this conclusion is insecure due to possible selection bias in the subgroups in whom this outcome was measured. No other statistically significant differences in outcome were identified. There was insufficient evidence to draw any conclusions from a further four included trials, involving a total of 179 patients, which compared other methods of anaesthesia (a 'light' general with spinal anaesthesia; intravenous ketamine; nerve blocks). REVIEWER'S
CONCLUSIONS: Regional anaesthesia and general anaesthesia appear to produce comparable results for most of the outcomes studied. Regional anaesthesia may reduce short-term mortality but no conclusions can be drawn for longer term mortality.