Wang-Zwische double lumen cannula-toward a percutaneous and ambulatory paracorporeal artificial lung.

We are developing a high performance double lumen cannula (DLC) for a minimally invasive, ambulatory and percutaneous paracorporeal artificial lung (PAL). The Wang-Zwische (W-Z) DLC was designed for percutaneous insertion into the Internal Jugular (IJ) vein with a drainage lumen open to both the superior vena cava (SVC) and the inferior vena cava (IVC) maximizing venous drainage. A separate collapsible but nondistensible membrane infusion lumen open to the right atrium (RA) achieves minimal recirculation allowing for total gas exchange. The W-Z DLC prototypes are made by a proprietary dip molding process with the "molded in" flat wire spiral stainless steel spring resulting in a flexible yet kink resistant thin wall (0.1 mm) outer cannula with one piece construction. With the ultra thin membrane infusion lumen collapsed, an introducer shaft fits tightly within the drainage lumen to facilitate insertion with placement at the SVC-RA-IVC junction. The W-Z DLC prototypes were tested while connected to a compact pump-gas exchanger circuit in three sheep (2 acute and one 15 day performance study). Insertion was simple, using standard percutaneous insertion techniques. Recirculation was as low as 2%. The 15 day performance study demonstrated our prototype 26 Fr W-Z DLC can achieve 2 L/min blood flow with minimal recirculation. The W-Z DLC design minimizes recirculation rate, maximizes flow lumen cross-sectional area, and maximizes achievable blood flow to enhance gas exchange performance allowing for one site percutaneous venovenous support.