A comparison of a heparin coated and a non-coated ECC arterial line blood filter

Two groups of five heparin coated (American Bentley AF 1040C) and non-coated (Gish Biomedical, Inc. AFS 40) ECC arterial line filters were compared In Vitro for pressure drop, debubbling time, air separating ability and clinically for blood handling ability. After CO 2 flush and following Directions for Use, the debubbling time for the AF 1040C was 178 ± 11 sec. (1 S.D.) and 183 ± 29 sec. for the AFS 40. The preparation times were not significantly different and were confirmed by doppler. The AFS 40 exhibited a resistance to blood flow approximately 68% of the AF 1040C resistance. In the 11-40 micron range, the AFS 40 performed as a significantly better bubble trap during crystalloid recirculation after debubbling. With blood prime, the AFS 40 appeared to be a better bubble trap. However, both filters pass equal numbers of 80 micron bubbles when challenged with a 200 ml·min −1 stream of air at 5·L·min −1 blood flow. Platelet loss, hemolysis index, and white cell counts showed no significant difference in the clinical comparison. Other studies have suggested that heparin coating facilitates filter preparation and have demonstrated clinical equivalency with non-coated filters. The AFS 40 and the AF 1040C appear to be clinically equivalent. The AFS 40 is a better bubble trap under normal ECC blood flow conditions.