Preoperative ketorolac increases bleeding after tonsillectomy in children

Abstract

Purpose: To compare the incidence of vomiting following codeine or ketorolac for tonsillectomy in children. Methods: We had planned to enrol 240 patients, aged 2-12 yr undergoing elective tonsillectomy into a randomized, single-blind study in University Children's Hospital. The study was terminated, after 64 patients because interim analysis of the data by a blinded non-study scientist concluded that the patients were at undue risk of excessive perioperative bleeding. After induction of anaesthesia by inhalation with N2O/halothane or with propofol 2.5-3.5 mg. kg-1 iv, the children were administered 150 μg · kg-1 ondansetron and 50 μg · kg-1 midazolam. Maintenance of anaesthesia was with N2O and halothane in O2. Subjects were administered either 1.5 mg · kg-1 codeine im or 1 mg · kg-1 ketorolac iv before the commencement of surgery. Intraoperative blood loss was measured with a Baxter Medi-Vac® Universal Critical Measurement Unit. Postoperative management of vomiting and pain was standardized. Vomiting was recorded for 24 hr after anaesthesia. Data were compared with ANOVA, Chi-Square analysis and Fisher Exact Test. Results: Thirty-five subjects received ketorolac. Demographic data were similar. The incidence of vomiting during the postoperative period was 31% in the codeine-group and 40% in the ketorolac-group. Intraoperative blood losses was 1.3 ± 0.8 ml · kg-1 after codeine and 2.2 ± 1.9 ml · kg-1 after ketorolac (mean ± SD) P < 0.05. Five ketorolac-treated patients had bleeding which led to unscheduled admission to hospital, P < 0.05, Exact Test. Conclusion: Preoperative ketorolac increases perioperative bleeding among children undergoing tonsillectomy without beneficial effects.