Ultra-rapid opioid detoxification increases spontaneous ventilation

Study Objective: To evaluate the effect of ultra-rapid opioid detoxification on spontaneous respiration. Design: Prospective study. Setting: University of Illinois, Chicago, Hospital. Patients: 20 ASA physical status I and II patients undergoing ultra-rapid opioid detoxification, and 5 ASA physical status I and II control patients undergoing surgical procedures. Interventions: Ultra-rapid opioid detoxification patients were anesthetized with propofol, intubated, and spontaneously ventilating. Opioid detoxification was achieved by giving repeated increasing intragastric doses of naltrexone. Control patients were anesthetized with propofol and 70% nitrous oxide and were time-based controls for opioid detoxification. Measurements and Main Results: Respiratory rate and minute ventilation were measured and increased 80% to 100% during opioid detoxification (p < 0.05). Respiratory rate and minute ventilation did not change in controls. Oxygen consumption and carbon dioxide (CO,) production were measured in separate studies and increased during ultra-rapid opioid detoxification with increases in spontaneous ventilation, but not when the patients were paralyzed. Conclusions: Spontaneous ventilation Increases during opioid detoxification without a change in end-tidal CO2. An increase in metabolism is produced in opioid withdrawal that is mediated by elevated muscle activity. (C) 1998 by Elsevier Science Inc.