Original Article

A Technique for the Effective Removal of Air from a Hollow Fiber Membrane Oxygenator Circuit

¹ PSICOR Inc., Brighton, MI
² University of Colorado Health Sciences Center, Denver, CO
³ The Childrens Hospital, Denver, CO

^* Direct communications to: Richard Berryessa, C.C.P., PSICOR Inc., 810 East Grand River, Brighton, MI 48116

Abstract

This paper describes some of the ways unwanted air can be introduced into a cardiopulmonary bypass circuit and a technique which has been shown to significantly decrease the resultant bubble counts. In this study air was introduced into a circuit (Hct. 20%) containing a Hollow Fiber Membrane Oxygenator (HFMO). Conventional techniques of recirculation (3 L/min.) and vigorous agitation/percussion were compared to recirculation with vacuum (gas phase of HFMO) for efficiency in reducing bubble counts measured after three minutes by a microbubble counter.

Conventional methods were ineffective after three minutes while vacuum for 3 minutes significantly (p = .001) reduced bubble counts (bubbles > 100 microns).

The microporous membrane allows efficient air removal with vacuum while recirculation/percussion did little to remove air which, in a blood perfusate, was not visible to the naked eye.

The application of vacuum not only increases safety but convenience when used in the priming and de bubbling of a circuit in routine and emergency case.