Alcohol and benzodiazepines may increase sleep-disordered breathing by decreasing
activity of pharyngeal dilating muscles, favoring the development of obstructive apneas
and hypopneas. Narcotics cause greater depression of wakeful respiration than the
previously mentioned drugs; however, the influence of narcotics on the upper airway
and breathing during sleep has not been studied. We, therefore, examined, in 12 healthy
adults, the effects of oral hydromorphone hydrochloride (2 and 4 mg) on breathing
during sleep and on a variety of awake respiratory variables (minute ventilation,
gas exchange, and chemoresponsiveness). In addition, awake pharyngeal inspiratory
airflow resistance was determined before and after narcotic administration to assess
the drug's influence on patency of the upper airway. Following both doses, minute
ventilation decreased, and carbon dioxide pressure increased. The 4-mg dose of hydromorphone
hydrochloride also produced a significant decrement in the hypoxic ventilatory response,
whereas hypercapnic responsiveness and pharyngeal resistance did not change following
either dose of the drug. Despite the respiratory depression during wakefulness described
previously, no significant change was observed in any measure of sleep-disordered
breathing after either dose of narcotic. We conclude that in healthy individuals without
suspected sleep apnea, oral hydromorphone in standard dosages does not significantly
increase sleep-disordered breathing. This result may be due to a lack of selective
depression of upper-airway muscular function by the doses of narcotic used.