Orthopnea

Orthopnea or orthopnoea (Greek from ortho, straight + pnoia, breath) is shortness of breath (dyspnea) which occurs when lying flat, causing the person to have to sleep propped up in bed or sitting in a chair. It is the opposite of platypnea. It is commonly seen as a late manifestation of heart failure, resulting from fluid redistribution into the central circulation, causing an increase in pulmonary capillary pressure. It is also seen in cases of abdominal obesity or pulmonary disease.

Causes

Orthopnea is due to increased distribution of blood to the pulmonary circulation while recumbent, but usually can be attributed to a more fundamental cause.

Orthopnea is often a symptom of left ventricular heart failure and/or pulmonary edema. It can also occur in those with asthma and chronic bronchitis, as well as those with sleep apnea or panic disorder. It is also associated with polycystic liver disease. From a neuromuscular perspective, orthopnea is a sign of severe diaphragmatic weakness. Under such circumstances, patients may describe shortness of breath when they bend over (e.g. when tying shoelaces).