Original Article

Report on the Clinical Trials of the Plexus Membrane Blood Oxygenator

Department of Extracorporeal Circulation Technology, College of Health Related Professions, Division of Cardiothoracic Surgery, Medical University of South Carolina, Charleston, SC

^* Address correspondence to: Amy Hodgson-Smith, Department of Extracorporeal Circulation Technology, College of Health Related Professions, Medical University of South Carolina, 171 Ashley Avenue, Charleston, SC 29425.

Abstract

Twenty adult patients gave informed consent to clinical cardiopulmonary bypass (CPB) trials with a new adult hollow fiber membrane oxygenator. Clinical CPB trials averaged 88 ± 25 min (mean ± 1 SD) for these patients that weighed 78 ± 13 Kg and had BSA's = 1.9 ± 0.2 m². Blood flow averaged 4.0 ± 0.8 L/min, and hypothermia was employed at 26.5 ± 2.4°C. FiO₂'s = 0.59 ± 0.15, and gas to blood flow ratios= 0.64 ± 0.18 were required to maintain the PaO2>100 mmHg and to accomplish alpha-stat. The oxygenator exhibited a pressure drop of 50-60 mmHg at 5.09 1/min and a heat exchanger performance factor over .55 during most of CPB.

Multiple regression analysis of the clinical database demonstrated that the FiO₂ required to achieve a desired PaO₂ was dependent on the blood flow, gas flow, and SvO₂ (r² = 0.83, standard error = 0.09). The gas flow required to accomplish alpha-stat was dependent on patient age, weight, blood flow, arterial blood temperature, and desired PaCO₂ (r² = 0.71, standard error= 0.6).

The Plexus blood oxygenator is safe for adult cardiopulmonary bypass and its clinical performance is statistically predictable.