Thursday, February 20, 2014

Stop Bang


A morbidly obese 35 year old gentleman who is 5'5" and 260lbs with a history of obstructive sleep apnea, hypertension, and insulin resistance undergoes pre-operative evaluation for a uvulopalatopharyngoplasty. He has excessive daytime sleepiness, loud snoring, witnessed apnea during sleep followed by a loud snort, fatigue, hypersomnolence, impaired concentration and memory, and a thick neck.

However, you also notice an elevated JVP, hepatomegaly, and some pedal edema. He has dyspnea on exertion and needs to rest after half a flight of stairs. An arterial blood gas shows a PaO2 on room air of 70, a PaCO2 of 48, a bicarbonate of 28, and a Hct of 55. Thyroid studies and electrolytes are normal. Pulmonary function tests show a low FVC, a low FEV1, a low ERV, but a normal FEV1/FVC ratio. EKG suggests right atrial and right ventricular hypertrophy. CXR is normal.

Challenge: Is there something else going on here?

Image is in the public domain, from Wikipedia.

4 comments:

Alex said...

pulmonary hypertension 2/2 OSA

child of god said...

Cor pulmonale causing right heart failure and fluid overload?

Daphne Tan said...

Cor pulmonale causing right heart failure and systemic fluid overload?

Craig Chen said...

great! love the answers
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Stop Bang

This is obesity hypoventilation syndrome, characterized by BMI>30 and awake alveolar hypoventilation (PaCO2>45) which cannot be attributed to any other diseases. The polycythemia is consistent with chronic hypoxemia. The PFTs are consistent with obesity and rule out COPD. The EKG and physical exam findings are concerning for pulmonary hypertension and right heart failure.

Source: UpToDate.