Paracorporeal artificial lung as a bridge to recovery or lung transplant

A paracorporeal artificial lung (PAL) was designed and built by MC Corporation for high gas exchange efficiency and low blood flow resistance as a bridge to recovery or lung transplant. The initial PAL implanted in a pulmonary artery-to-artery (PA-PA) configuration supported gas exchange in normal sheep (n=8) up to 7 days. 4/8 sheep survived, but 4/8 experienced right heart failure. Following modifications to lower resistance with an inflow compliance chamber, 6/7 exhibited good cardiac function and total gas exchange for 72 h. We identified several additional complications including acute massive hemothorax (2/24), late (>24 h) hemothorax (4/24), cannula kinking (2/24), and anastomotic stricture (3/24). We addressed bleeding by a heparin free window and reduced dose, changed cannulae position and used Gore-Tex reinforced graft. We then encountered no hemothorax or outflow obstruction. Using our LD₁₀₀ smoke/burn ARDS sheep model, we compared PAL (n=8) to volume-controlled mechanical ventilation (VCMV, n=6) in a prospective, randomized, controlled, unblinded, outcomes study to assess outcomes. Both groups were managed with a VCMV algorithm. 6/8 PAL vs. 1/6 VCMV sheep survived the 5-day study. Next, we will study impact on survival and pathophysiology from a LD₁₀₀ smoke/burn injury using injection molded PALs with biocompatible surfaces.