Perlman Lung Mechanics Laboratory
Dr. Perlman's Lung Mechanics Laboratory is developing new mechanical and pharmacological means of reducing ventilation injury of edematous lungs.
In the acute respiratory distress syndrome (ARDS), such as can occur in novel coronavirus patients, inflammation causes liquid to leak out of the pulmonary blood vessels into the alveoli, the smallest airspaces of the lungs. Such liquid-flooding of alveoli, known as edema, makes breathing difficult. Thus, ARDS patients are treated with mechanical ventilation, which assists breathing.
Mechanical ventilation, however, often causes an additional over-distension injury of the lungs—ventilation induced lung injury (VILI)—that can prevent recovery. The mortality rate for ARDS/VILI exceeds 35%..
We study the micromechanics of flooded alveoli in the lungs and have identified anatomical sites of stress concentration that are likely sites of VILI. Furthermore, we developed the first means of determining surface tension in flooded alveoli of the lungs. With these methods, we showed that the degree of stress concentration is proportional to the surface tension at the air-liquid interface in flooded alveoli.
Also, we identified compounds that, through a novel mechanism, lower surface tension in the lungs. We are investigating the mechanical mechanism through which ventilation injury spreads through edematous lungs, and we are testing the surface-tension lowering compounds for the ability to reduce VILI and improve oxygenation. One compound in particular, sulforhodamine B, is a strong candidate for helping not-yet-ventilated ARDS patients avoid mechanical ventilation and helping ventilated ARDS patients survive.