Clinical Evaluation of a Microporous Hollow-fiber Membrane Oxygenator with Large Gas Transfer Capability

Abstract

A capillary tube membrane oxygenator composed of microporous hollow fibers has been evaluated in 400 cases of cardiac surgery. The available membrane area in this device is 5.4 M2. The priming volume of the oxygenator and an integral heat exchanger is 700 ml. The perfusions were conducted with moderate hypothermia and hemodilution. Arterial pO2 was controlled by appropriate adjustment of the FiO2. The pCO2 was controlled by changing the gas flow. The duration of perfusion was up to 476 minutes at blood flow rates of 2.0 to 6.7 L/min. Oxygen transfer was as high as 352 ml/min. The mean arterial pO2 was 281 mm Hg and the pCO2 38 mm Hg. Platelet count did not change significantly during perfusion. This device has proven to provide good gas exchange for nearly eight hours in this series. Two units developed small leaks of blood into the gas phase of the device. These leaks did not affect gas exchange. This oxygenator-heat exchanger unit has proven to be simple to prime, easy to operate, provide adequate gas exchange for all adults and safe for cardiac surgery.