Abstract

The obesity hypoventilation syndrome (OHS) characterized by persistent hypercapnia with obesity has many causes. Probably the most common cause is the obstructive sleep apnea syndrome and related conditions, but some cases may occur along with depressed chemosensitivity and few apneas during sleep. The mechanisms that produce waking hypercapnia are still uncertain. Treatment of OHS consists of weight management and sometimes requires treatment with continuous applied pressure or non invasive positive pressure ventilation.