Comparison of the ventilatory effects of morphine and buprenorphine in children

This study was a prospective, randomized comparison of the ventilatory effects of equianalgesic single-doses of morphine, 100 micrograms/kg, and buprenorphine, 3.0 micrograms/kg, administered intravenously to 20 children (5-8 years of age) after elective ophthalmic surgery. The decrease in ventilatory rate and acute change in the arteriolar oxygen saturation and the increase in end-tidal CO2 levels were statistically significantly greater in magnitude and duration after buprenorphine than after morphine. For both drugs, the time, duration and magnitude of ventilatory changes varied appreciably between individuals. No child had apnea or hypoventilation requiring assistance. The authors conclude that acutely administered buprenorphine depresses ventilation to a greater degree than morphine. The maximal ventilatory effect of buprenorphine occurs later than with morphine, and ventilatory depression after buprenorphine may develop late. For safety, all children given opioids intravenously should be observed until they are fully responsive and ventilatory control has stabilized.