What is the medical term for shortness of breath that worsens when lying flat?

The medical term for shortness of breath that worsens when lying flat is orthopnea. This condition typically indicates heart failure or other cardiovascular issues, where the fluid can accumulate in the lungs when supine, making breathing difficult.

Paroxysmal nocturnal dyspnea refers specifically to episodes of sudden shortness of breath that awaken the patient from sleep, often due to fluid redistribution upon lying down. While both conditions can involve a worsening of breath when lying flat, paroxysmal nocturnal dyspnea specifically describes a situation occurring at night after sleeping, which makes it different from orthopnea, where the symptom may occur whenever the patient is in a recumbent position.

Understanding these distinctions is crucial in accurately assessing and treating respiratory symptoms in emergency settings.