Dyspnea

Dyspnea is a subjective sensation of breathing discomfort—often described as air hunger, chest tightness, or an inability to get enough air. It can occur with or without measurable hypoxemia and affects up to 80% of people with advanced illness. The patient’s report is therefore not disproved by a relatively reassuring oxygen saturation. The sensation develops when the brain perceives a mismatch between the effort required to breathe and the respiratory system’s ability to meet that demand. Advanced disease can create this mismatch through airway obstruction, pulmonary congestion, pleural effusion, infection, respiratory muscle weakness, anemia, or reduced cardiac function. Fear then increases muscle tension and ventilatory demand, which can intensify the sensation further. Anxiety may amplify dyspnea, but labelling the symptom as “only anxiety” is unsafe until physical contributors and acute deterioration have been considered. A patient may be visibly distressed, sitting forward and using accessory muscles, while another reports severe breathlessness with few obvious signs. Both require assessment. Respiratory rate and oxygen saturation provide useful clinical information, but neither replaces the patient’s description of the symptom. The aim at end...