Effects of intravenous ketorolac and fentanyl combined with midazolam on analgesia and side effects during extracorporeal shock wave lithotripsy.

BACKGROUND: Extracorporeal shock wave lithotripsy (ESWL) is usually carried out on ambulatory or outpatient basis, and thus an appropriate anesthesia with minimal side effects is required. This study was to compare the analgesic and side effects of intravenous ketorolac with that of intravenous fentanyl, in combination with midazolam in ESWL. METHODS: Sixty patients were randomly divided into two groups; group K (n = 30) received 60 mg ketorolac i.v. 30 min before ESWL and group F (n = 30) received 100 micrograms fentanyl i.v. 3 min before ESWL. All patients received 2.5 mg midazolam i.v. 3 min before ESWL for intraoperative sedation. The pain intensity was evaluated by a numeric rating scale (NRS). A supplemental analgesia with intravenous fentanyl 25 micrograms was given when inadequate analgesia occurred (NRS > 3). Oxygen supplement through a face mask was given when the SpO2 fell below 94%. Side effects (nausea, vomiting, dizziness) and the time of discharge from post-anesthesia room (PAR) were recorded. The criterion of discharge from PAR was absence of any discomfort especially when the patient held upright. RESULTS: There was no difference between two groups in the demographic data, number of shock waves, duration of ESWL procedure, and fentanyl supplement. The incidence of oxygen supplement was lower in ketorolac group (1/30) compared with that of fentanyl group (20/30), P < 0.01. The frequency of dizziness was lower in ketorolac group (1/30) than that in fentanyl group (25/30), P < 0.01. Three patients in fentanyl group complained of nausea, but none did in ketorolac group. The discharge time from PAR was significantly shorter in ketorolac group (14.7 +/- 8.4 min) than that in fentanyl group (49.5 +/- 14.6 min), P < 0.01. CONCLUSIONS: Both intravenous ketorolac and fentanyl in combination with midazolam could provide good anesthesia for ESWL. However, ketorolac plus midazolam had less side effects and allowed shorter discharge time from PAR. We suggest that intravenous ketorolac combined with midazolam is a safe and effective anesthetic regiment for ESWL, particularly on ambulatory basis.