Study objective: To study the efficacy of intravenous ketorolac, morphine, and both drugs in combination in reducing pain in acute renal colic.
Methods: We conducted a prospective, double-blinded, randomized controlled trial in an urban, teaching emergency department. Patients aged 18 to 55 years and with a clinical diagnosis of acute renal colic and a pain rating greater than 5 on a 10-cm visual analogue scale or at least "moderate pain" on a 4-category verbal pain scale were eligible for inclusion. Exclusion criteria were contraindication to nonsteroidal anti-inflammatory drugs or opiates, a history of drug dependence, presence of peritonitis, or analgesics within 6 hours of presentation. Patients received either morphine 5 mg at time zero and 5 mg at 20 minutes, ketorolac 15 mg at time zero and 15 mg at 20 minutes, or a combination of both. Primary outcomes were pain reduction and the need for rescue analgesia at 40 minutes.
Results: Of the 555 consecutive patients screened, 158 patients met inclusion criteria and 130 patients were randomized during 6 months. Mean difference in change in pain score (visual analog scale 40 minutes minus visual analog scale 0 minutes) between combination group and morphine group was 1.8 cm (95% confidence interval [CI] -3.3 to -0.1) and, compared to the ketorolac group, was 2.2 cm (95% CI -3.7 to -0.5); P<.003. Patients with combination therapy were less likely to require rescue morphine compared to the morphine group (odds ratio 0.2; 95% CI 0.1 to 0.7; P=.007).
Conclusion: A combination of morphine and ketorolac offered pain relief superior to either drug alone and was associated with a decreased requirement for rescue analgesia.