Noninvasive Ventilation in Obesity Hypoventilation Syndrome. Short- and Long-Term Outcomes

Obesity hypoventilation syndrome (OHS) is a chronic hypoventilation disorder characterized by a body mass index (BMI) ≥ 30 kg/m2 and daytime hypercapnia (PaCO2 > 45 mmHg) in patients with no other possible causes of hypoventilation. Positive airway pressure (PAP) therapy is the mainstay of OHS respiratory management. PAP therapy improves gas exchange, quality of sleep and life, and survival in OHS patients with no difference in the effect size among different PAP modalities; PAP adherence appears to be a major predictor of outcome. Survival of OHS patients treated with noninvasive ventilation (NIV) is higher as opposed to several other NIV-treated patients with various hypoventilation syndromes. PAP modes other than CPAP and bi-level PAP may benefit OHS patients, but more evidence is required.