Four studies were included in the review (n=1,000 patients). Two studies were randomised controlled trials (RCTs). One RCT reported allocation sequence and blinding of investigators. No patients were lost to follow-up in any of the studies, but one study did not report the duration of follow-up. Follow-up in the other studies ranged from 10 days to three months
Compared with control treatments, anticoagulants were associated with a significant reduction in pulmonary embolism (RR 0.37, 95% CI 0.17 to 0.80; four studies).
There was no evidence of significant differences between groups in the rate of deep venous thrombosis or haematoma enlargement.
Compared to control treatments, anticoagulants were associated with a reduction (non-significant trend) in all-cause mortality (RR 0.76, 95% CI 0.57 to 1.03; three studies).
Sensitivity analyses changed some of the overall findings. With the removal of a study from the meta-analysis that contributed the most weight estimating pulmonary embolism rate, the summary estimate was no longer significant. With the removal of the same study (differently weighted) from the meta-analysis estimating haematoma enlargement, the results were statistically significant indicating risk of haematoma was increased with anticoagulants compared with control treatments. With the removal of one study from the meta-analysis estimating mortality, the results were statistically significant and indicated that risk of death was reduced with anticoagulants compared with control treatments.
There was no evidence of significant heterogeneity in any of the analyses.