Effect of rofecoxib on platelet aggregation and blood loss in gynaecological and breast surgery compared with diclofenac

Background. Non-selective cyclooxygenase (COX) inhibitors or non-steroidal anti- inflammatory drugs (NSAIDs) are frequently omitted for perioperative pain relief because of potential side-effects. COX-2-selective inhibitors may have a more favourable side-effect profile. This study tested the hypothesis that the COX-2-selective inhibitor rofecoxib has less influence on platelet function than the NSAID diclofenac in gynaecological surgery. In addition, analgesic efficacy and side-effects of the two drugs were compared. Methods. In this single-centre, prospective, double-blind, active controlled study, women undergoing vaginal hysterectomy (n=25) or breast surgery (n=25) under general anaesthesia received preoperatively 50 mg of rofecoxib p.o. followed 8 and 16 h later by two doses of placebo or three doses of diclofenac 50 mg p.o. at the same time points. We assessed arachidonic acid-stimulated platelet aggregation before and 4 h after the first dose of study medication, estimated intraoperative blood loss, and haemoglobin loss until the first morning after surgery. Analgesic efficacy, use of rescue analgesics, and side-effects were also recorded. Results. In the rofecoxib group, stimulated platelet aggregation was disturbed less (P=0.02), and estimated intraoperative blood loss (P=0.01) and the decrease in haemoglobin were lower (P=0.01). At similar pain ratings, the use of anti-emetic drugs was less in the rofecoxib group (P=0.03). Conclusion. Besides having a smaller effect on platelet aggregation, one oral dose of rofecoxib 50 mg given before surgery provided postoperative analgesia similar to that given by three doses of diclofenac 50 mg and was associated with less use of anti-emetics and less surgical blood loss in gynaecological surgery compared with diclofenac.