Why Do Asthmatics “Stack Breaths”? Severe asthma isn’t just wheeze, it’s airway narrowing that hits expiration hardest. Bronchospasm airway swelling thick mucus → air gets in, but can’t get out fully → the next breath starts early → breath stacking (air trapping) → dynamic hyperinflation → rising work of breathing, fatigue, and potential ventilation failure → in extreme cases: reduced venous return → BP can drop Learn. Adapt. Respond. | The Medical Lounge