Ketorolac versus fentanyl for postoperative pain management in outpatients

Objective: The purpose of this study was to compare the efficacy and safety of i.v. ketorolac and fentanyl for moderate to severe postoperative pain in patients undergoing elective surgery in an ambulatory surgery unit. Design: A double-blind randomized trial. Setting: An ambulatory surgery unit in a university-affiliated hospital. Patients: Sixty-nine patients undergoing elective laparoscopy, inguinal hernia repair, or knee arthroscopy were enrolled. Intervention: Patients were randomly assigned to receive intravenous ketorolac 30 mg (n = 38) or fentanyl 50 μg (n = 31) for moderate to severe postoperative pain. Outcome Measures: Pain, assessed using a 100- mm visual analog scale and a 5-point verbal pain scale: adverse effects, as well as vital signs were recorded every 15 min for 150 min or until discharge from the postanesthesia care unit, 6 and 24 h after discharge. Results: Pain reduction on both visual analog and verbal scales was significantly greater with fentanyl than ketorolac at 15 min. In addition, the proportion of patients requiring remedication at the 15-min time point was significantly greater in the ketorolac group. However, there were no significant differences between fentanyl and ketorolac between 30 and 150 min after surgery. Notably, pain reduction was significantly greater with ketorolac on the verbal scale at the 6 h measurement. Conclusions: Ketorolac appears not to be as effective as fentanyl in treating early postoperative pain. Although fentanyl still appears to be the drug of choice in the early postoperative period, the parenteral use of ketorolac was more effective during the later postoperative period in providing longer lasting analgesia.