Which term describes shortness of breath that occurs when lying flat?

• A. Bibasilar
• B. PND
• C. Orthopnea
• D. Bradycardia

Answer: (C)

Orthopnea describes shortness of breath that worsens when lying flat and improves when sitting up. When you lie down, venous return to the heart increases, which raises pressures in the left atrium and pulmonary circulation. In someone with heart dysfunction, this can push fluid into the lungs and trigger dyspnea. Patients often report needing to prop themselves up on multiple pillows to breathe easier. Paroxysmal nocturnal dyspnea is related but occurs at night after lying down for a few hours, waking the person with sudden dyspnea. Bibasilar refers to findings at the lung bases, not the positional nature of the symptom, and bradycardia is a slow heart rate. The term that best fits this positional breathing difficulty is orthopnea.