Abstract

Evaluation of Quadrox-i® Adult Hollow Fiber Oxygenator with Integrated Arterial Filter

^* Penn State Hershey Pediatric Cardiovascular Research Center
^‡ Department of Surgery, Penn State Milton S. Hershey Medical Center, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, Pennsylvania
^§ Department of Bioengineering, Penn State Milton S. Hershey Medical Center, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, Pennsylvania
^† Public Health and Sciences, Penn State Milton S. Hershey Medical Center, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, Pennsylvania

Address correspondence to: Akif Ündar, PhD, Professor of Pediatrics, Surgery, and Bioengineering, Penn State Hershey College of Medicine, Department of Pediatrics—H085, 500 University Drive, P.O. Box 850, Hershey, PA 17033-0850. E-mail: aundar@psu.edu

Received: 28 September 2009
Accepted: 16 January 2010

Abstract

Gaseous microemboli (GME) remain a challenge for cardiopulmonary bypass procedures in adult as well as pediatric cardiac surgery patients. The present study tested the effectiveness of a new adult membrane oxygenator in models both with and without an integrated arterial filter to evaluate GME trapping capability and determine membrane pressure drops at various flow rates and temperatures. The experimental circuit included a RotaFlow centrifugal blood pump, Quadrox-i® (n = 8) or Quadrox® (n = 8) adult microporous membrane oxygenator, and Sorin adult tubing package. A Sorin Cardiovascular® VVR® 4000i venous reservoir served as pseudo-patient. The circuit was primed with 900 mL heparinized human red blood cells and 300 mL Lactated Ringer’s solution. The final hematocrit was 36%. Tests were performed at different flow rates (4 L/min, 5 L/min, and 6 L/min) and temperatures (35° and 30°). Five mL of bolus air was injected into the venous line over 15 seconds using a syringe connected to a 3/8 × 1/2 luer connector. The Quadrox-i® adult microporous membrane oxygenator with integrated arterial filter had a similar pressure drop at 4 L/min and 35°C compared with Quadrox® membrane oxygenator whereas it had higher pressure drops at 5 L/min and 6 L/min (p <.001). Quadrox-i® adult microporous membrane oxygenator reduced the total emboli count and total emboli volume delivered to the pseudo-patient at all flow rates (p <.001). The emboli handling of Quadrox-i® adult microporous membrane oxygenator was not affected by flow rate and temperature. Compared with the traditional Quadrox® oxygenator, Quadrox-i® adult microporous membrane oxygenator with integrated arterial filter and Softline coating has improved GME handling capacity.