Two Hours of In Vivo Lung Perfusion Improves Lung Function in Sepsis-Induced Acute Respiratory Distress Syndrome

Sepsis is the leading cause of acute respiratory distress syndrome (ARDS) in adults and carries a high mortality. Utilizing a previously validated porcine model of sepsis-induced ARDS, we sought to refine our novel therapeutic technique of in vivo lung perfusion (IVLP). We hypothesized that 2 hours of IVLP would provide non-inferior lung rehabilitation compared to 4 hours of treatment. Adult swine (n=8) received lipopolysaccharide to develop ARDS and were placed on central venoarterial extracorporeal membrane oxygenation. Animals were randomized to 2 vs. 4 hours of IVLP. The left pulmonary vessels were cannulated to IVLP using antegrade Steen solution. After IVLP treatment, the left lung was decannulated and reperfused for 4 hours. Total lung compliance and pulmonary venous gases from the right lung (control) and left lung (treatment) were sampled hourly. Biochemical analysis of tissue and bronchioalveolar lavage was performed along with tissue histologic assessment. Throughout IVLP and reperfusion, treated left lung PaO2/FiO2 ratio was significantly higher than the right lung control in the 2-hour group (332.2±58.9 vs. 264.4±46.5, p=0.01). In the 4-hour group, there was no difference between treatment and control lung PaO2/FiO2 ratio (258.5±72.4 vs. 253.2±90.3, p=0.58). Wet-to-dry weight ratios demonstrated reduced edema in the treated left lungs of the 2-hour group (6.23±0.73 vs. 7.28±0.61, p=0.03). Total lung compliance was also significantly improved in the 2-hour group. Two hours of IVLP demonstrated superior lung function in this preclinical model of sepsis-induced ARDS. Clinical translation of IVLP may shorten duration of mechanical support and improve outcomes.