Sleep and respiration: a postscript.

The recent advances in our understanding of breathing in sleep include an evolution in the selection and surgical therapy of patients with the sleep apnea syndrome. Recent work suggests that shorter polysomnographic studies may be adequate for diagnostic purposes in many sleep apnea patients. It is now clear that central apnea may occur, paradoxically, in patients with either very blunted chemical drives to breathe or increased drives to breathe.