Data were extracted as required to calculate weighted mean differences (WMDs) with 95% confidence intervals (CIs) for continuous outcomes and relative risks (RRs) with 95% CIs for dichotomous outcomes
Primary outcomes included estimated intraoperative blood loss, postoperative drainage volume and blood transfusion requirement. Secondary outcomes included mortality, duration of operation, whether operation had to be repeated, complete blood count and coagulation assay, postoperative complications, duration of postoperative hospital stay and withdrawals and dropouts.
Two reviewers extracted data independently.