Pickwickian syndrome, 20 years later.

The Pickwickian Syndrome stimulated new pathophysiological concepts in regard to control of ventilation. With the advent of sleep laboratories, the peculiar sleep apnea occurring in some of these patients has been explained on the basis of intermittent upper airway obstruction. Two patients with different manifestations of the Pickwickian Syndrome are presented. The suggestion is made that these two subsyndromes should have unique designations. The Auchincloss Syndrome is manifested by right heart failure and respiratory acidosis in obese patients who are alert and have no major abnormality of breathing pattern. The fundamental cause of this abnormality is the increased work of breathing caused by the obesity. The cost of breathing is so high that the ventilatory regulation is compromised and respiratory acidosis results. The Gastaut Syndrome is characterized principally by hypersomnia and sleep apnea. The fundamental defect is upper airway obstruction during sleep, resulting in increased work of breathing, which together with the increased work caused by obesity leads to respiratory acidosis and right ventricular failure. Hypersomnia, rather than heart failure or respiratory acidosis, is the major manifestation of this syndrome, and is the result of sleep loss.