Difficulty in breathing when lying flat. Orthopnoea is a symptom of heart failure and pulmonary oedema, and also occurs with asthma and chronic obstructive pulmonary disease (see pulmonary disease, chronic obstructive).
A form of di?culty in breathing so severe that the patient cannot bear to lie down, but must sit or stand up. As a rule, it occurs only in serious affections of the heart or lungs.
n. breathlessness that prevents the patient from lying down, so that he has to sleep propped up in bed or sitting in a chair. —orthopnoeic adj.
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