Extracorporeal Support Vascular Access: 3D Printing Custom Cannulas.

Abstract

Extracorporeal life support (ECLS) requires specialized cannulas for vascular access that are dependent on each patient's needs, size, and unique vascular anatomy. There are currently no commercially available drainage cannulas suitable for patients smaller than 1.5 kg. This study presents the development of a novel 6 Fr cannula for blood drainage to be used in these small patients. Cannulas were manufactured using stereolithography three-dimensional (3D) printing on Form 3 and Form 3B printers and tested in vitro using 3% glycerol. Drainage pressure at 100 ml/min was -39 ± 2 and -42.3 ± 9 mm Hg, for Form 3 and Form 3B, respectively. Maximum flow rate and drainage pressures were 185.8 ± 15 ml/min and -80 ± 2 mm Hg and 165 ± 21 ml/min and -85.7 ± 12 mm Hg for Form 3 and Form 3B, respectively. Three Form 3B cannulas were tested in vivo in an ECLS piglet model, the best of which had a maximum blood flow rate of 139 ml/min at -32 mm Hg drainage pressure. Cannulas 3D-printed using the Form 3 and Form 3B printers exhibited appropriate size and flow rates (~100 ml/kg/min) for ECLS needed to support premature patients with minimal complexity in the fabrication process. These cannulas should be optimized in preclinical research using translational models.