Use of naloxone in septic shock.

Experimental and clinical evidence show that endogenous opiates (endorphins) contribute to the pathophysiology of circulatory shock. The authors evaluated the effectiveness and safety of continuous infusion of naloxone in five septic patients with prolonged hypotension unresponsive to volume replacement and dopamine infusion. Naloxone (2 mg bolus) was intravenously administered and continued at 0.25 mg/hr for 24 to 48 hours. All five patients had significant increase in mean arterial pressure of between 20 and 30 mmHg (P less than 0.0012). Cardiac index, systemic vascular resistance, and pulmonary arterial pressure were not significantly altered; however, there was a significant difference in pulmonary capillary wedge pressure (P less than 0.034) and urinary output (P less than 0.0273). Subjects did not experience side effects with naloxone. We conclude that continuous infusion of naloxone can reverse endorphin-mediated hypotension in septic shock patients.