Comparison of intramuscular ketorolac tromethamine and morphine sulfate for analgesia of pain after major surgery.

Ketorolac tromethamine is a new injectable nonnarcotic analgesic. In a parallel, double-blind study, the analgesic efficacies of single intramuscular doses of ketorolac 10, 30 and 90 mg were compared with those of morphine sulfate 6 and 12 mg. Two hundred forty-one patients were categorized according to type of surgical procedure and severity of pain. Pain intensity and pain relief were assessed for 6 hours by scoring standard verbal and visual analog scales. Patients receiving ketorolac 10, 30 or 90 mg or morphine (MS) 12 mg all had significantly better pain relief in almost all measurements performed than those receiving MS 6 mg (p less than 0.05). Ketorolac 10 and 30 mg were as effective as morphine 12 mg during the entire 6-hour observation period, and ketorolac 90 mg was more effective than morphine 12 mg during the entire 6 hours. Patients with pain related to major surgery (e.g., cholecystectomy and abdominal hysterectomy) were better able to distinguish analgesic potency of morphine than those having less traumatic procedures (e.g., tendon and ligament repairs).