Left untreated, OHS often results in right-sided heart failure,1 pulmonary hypertension1 and polyglobulia,2 contributing to substantial morbidity and probable early mortality.1 So it’s important to recognise OHS in your patients and get them treated.
Indications for OHS include:
Obese patients who continue to feel sleepy during the day and suffer from headaches even after being treated with continuous positive airway pressure (CPAP) therapy for their OSA. These patients may even show a low apnoea–hypopnoea index (AHI).
Permanently low oxygen levels (less than 90%).
Dyspnoea on exertion, since patients with OSA alone generally do not develop dyspnoea on exertion.
The absence of an alternative cause of hypoventilation is an important criterion for the diagnosis of OHS.
Piper JP, Grunstein RR. Obesity hypoventilation syndrome. (2011) Am J Respir Crit Care Med 183:292-298
Parameswaran, K, Todd, DC, Soth, M . Altered respiratory physiology in obesity. Can Respir J. 2006 13(4): 203-210