INTRAVENOUS MORPHINE FOR EARLY PAIN RELIEF IN PATIENTS WITH ACUTE ABDOMINAL-PAIN

Objective: To determine whether morphine affects evaluation or outcome for patients with acute abdominal pain. Methods: Prospective, double- blind, placebo-controlled administration of morphine sulfate (MS) or n ormal saline (NS) in the setting of acute abdominal pain, The study wa s performed at a military ED with an annual census of 60,000 visits. P atients greater than or equal to 18 years old who had abdominal pain f or less than or equal to 48 hours were included. Patients who were all ergic to MS or who had systolic blood pressures <90 mm Hg were exclude d. The physicians indicated a provisional diagnosis, a differential di agnosis, and a provisional disposition. Study solution was titrated to the patient's assessment of adequate analgesia (up to a volume equiva lent of 10 mg of MS); pain response was monitored using a visual analo g scale (VAS). The patients were followed until diagnosis occurred or symptoms resolved. Results: Of 75 patients enrolled, 71 completed the study; 35 patients received MS and 36 received NS. More than half (44; 62%) of the patients were admitted from the ED; 28 patients underwent surgery. The VAS pain level improved more for the MS group, 3.9 +/- 2 .8 cm, than it did for the NS group, 0.8 +/- 1.5 cm (p < 0.01). Study solution dose was less in the MS group than it was in the NS group, 1. 5 +/- 0.5 mL vs 1.8 +/- 0.4 mL (p < 0.01). There was no difference bet ween the groups when comparing accuracy of provisional or differential diagnosis with that of final diagnosis. Differences between provision al and actual dispositions were the same in all groups. There were 3 d iagnostic or management errors in each group. Conclusions: When compar ed with saline placebo, the administration of MS to patients with acut e abdominal pain effectively relieved pain and did not alter the abili ty of physicians to accurately evaluate and treat patients.