Cause of central cyanosis include all the following except: (A) Chronic asthma, (B) Congestive pulmonary stenosis, (C) Congestive hea failure, (D) Alveolar hypotension
Answer is C. CHF is a cause for peripheral cyanosis and not central cyanosis. Cyanosis when present in asthma,pulmonic stenosis and alveolar hypoventilation is of central type. Ref Harrison 19th edition pg 249