DIFFICULTIES IN DIAGNOSING NARCOTIC OVERDOSES IN HOSPITALIZED-PATIENTS

OBJECTIVE: To describe the clinical presentation of narcotic overdose in hospitalized patients and to differentiate this circumstance from o ther conditions often misdiagnosed as overdose. DESIGN: Case series. S ETTING: Two acute-care teaching hospitals. PATIENTS: Forty-three hospi talized patients who received naloxone for a clinically suspected narc otic overdose. INTERVENTIONS: Two investigators independently evaluate d each incident to determine whether the patient had a narcotic overdo se. The patients were judged to have had an overdose if caregivers doc umented an immediate improvement in mental status, respiratory rate, o r blood pressure after naloxone administration.MEASUREMENTS: The clini cal presentation of a narcotic overdose in hospitalized patients was d efined. Conditions misdiagnosed as an overdose were determined.MAIN RE SULTS: Symptoms improved rapidly with the administration of naloxone i n 28 incidents (65 percent) and were designated overdose. In 15 other instances there was no improvement in symptoms; these patients were de signated nonoverdose. Only half of die overdose patients had a respira tory rate <8 breaths/min immediately prior to naloxone administration. Only two of die overdose patients had the classic triad of symptoms ( respiratory depression, coma, and pinpoint pupils). Other overdose pat ients had only one or two of die classic signs. The clinical presentat ion of narcotic overdoses in hospitalized patients did not include res piratory depression, hypotension, or coma in the majority of patients. All overdose patients showed a decrease in mental status. The majorit y of nonoverdose patients had pulmonary conditions that were misdiagno sed as a narcotic overdose. CONCLUSIONS: Narcotic overdoses in hospita lized patients seldom fit the classic description. The lack of respira tory depression does not mean the absence of a narcotic overdose. Pati ents who receive narcotics and develop a significant decrease in menta l status should be evaluated for a possible overdose. Pulmonary, neuro logic, cardiovascular, and electrolyte abnormalities often are misdiag nosed as a narcotic overdose in hospitalized patients.