Mechanical Forces Producing Pulmonary Edema in Acute Asthma

Abstract

Since patients with asthma have great difficulty in emptying their lungs, it has generally been assumed that large positive intrathoracic pressures are generated in this condition. On the other hand, the clinical observation that patients with acute asthma demonstrate severe intercostal retractions on inspiration suggests that large negative intrathoracic pressures are generated. Very negative peak inspiratory pleural pressures have been reported during induced bronchospasm.^{1 , 2} Because fluid accumulation in the lung is enhanced by very negative mean pleural pressures³ and because edema of the airways is an important part of the pathophysiology of asthma⁴ we measured pleural pressures in patients with . . .