SAFETY OF PREHOSPITAL THERAPY WITH MORPHINE-SULFATE

The safety of prehospital pharmacologic therapy has not been well studied. The authors evaluated field use of morphine sulfate (MS) in San Francisco County over a 6-month period. Paramedics assessed patients for ischemic chest pain (ICP) and/or pulmonary edema (PE), made base hospital contact, and administered 2- to 4-mg doses of intravenous morphine according to treatment protocols. Clinical assessments and patient responses to therapy were recorded by both field paramedics and emergency department (ED) physicians. Safety was evaluated by determining the (1) accuracy of paramedic field assessment, (2) appropriateness of field administration of MS, and (3) therapeutic complications. During the study period, paramedics administered MS to 84 patients. In 69 cases paramedic assessment of either ICP and/or PE corresponded to ED physician diagnosis. In five cases paramedics correctly recognized ICP but missed physical findings of PE. In this group the paramedics' assessment was considered inaccurate but the judgement to give MS was considered appropriate. In the remaining 10 cases paramedics identified ICP or PE but the ED physician diagnosed a different condition. These assessments were considered inaccurate and the management inappropriate. Therefore, overall paramedic accuracy was 77% (true rate 73% to 82%, 95% confidence interval); appropriateness of therapy was 88% (true rate 85% to 92%, 95% confidence interval); and the overall complication rate was 6% (true rate 2% to 12%, 95% confidence interval). Complications of respiratory depression or hypotension occurred in only one of the cases in which MS was inappropriately administered. The authors conclude that paramedics functioning within a system of base hospital medical direction can safely administer MS. The frequency of inappropriate MS administration and the complication rate from both erroneous and appropriate drug administration is acceptably low. © 1992.