ABSTRACT
During the last three decades interest in the interactions between sleep and breathing has focused on the syndrome of obstructive sleep apnea. However, it is also clear that sleep can alter breathing in a variety of ways independent of frank sleep apnea. Edward Smith reported in 1860 that ventilation is reduced during sleep in apparently healthy subjects (1). This has been confirmed multiple times in recent years, with the decrement in ventilation commonly resulting from a sleep-associated reduction in tidal volume (2,3).
