Clinical evaluation of five commercially available adult oxygenators in terms of pressure drop during normothermic and hypothermic cardiopulmonary bypass.
BACKGROUND
It is well documented that trans-membrane pressure drop (TMPD) of hollow-fiber membrane oxygenators (HFMO) may lead to hemolysis, damage to platelets, and systemic inflammatory response. The purpose of this study was to evaluate five commercially available adult oxygenators in terms of pressure drop during normothermic and hypothermic cardiopulmonary bypass (CPB).


METHODS
In a clinical setting, 5 different adult HFMOs were tested in terms of TMPDs. Forty patients scheduled for cardiac surgery were enrolled in the study and were divided into 5 groups according to the type of oxygenator used during CPB: group J (Maquet Quardox n=8), group A (Affinity NT n=8), group P (Polystan Safe Maxi n=8), group T (Terumo Capiox SX 18 n=8) and group C (COBE APEX-TM n=8). Clinical parameters were collected during CPB, including mean arterial pressure (MAP), pump flow, temperature, hematocrit, duration of CPB, cross-clamp time and bypass time. TMPDs of pre-oxygenator and post-oxygenator pressures were recorded at the start of systemic cooling (T1), 10 min after stable hypothermia at 30 degrees C (T2), and at termination of rewarming before the end of CPB (T3).


RESULTS
There were no significant differences among the 5 groups in pump-flow rate, temperature, hematocrit, and mean arterial pressure during CPB. TMPDs of group J were the lowest at different time-points (T1, 30.71 +/- 8.42mmHg; T2, 25.71 +/- 5.41 mmHg; T3, 27.42 +/- 13.01 mmHg). Compared to the other 3 groups (P, C and T groups), TMPDs of groups J and A at various time-points were lower (J group compared with the other three groups (p<0.001). Although TMPDs in groups A, P and T during hypothermia were higher than during normothermia and post-rewarming, there was no significant statistical difference (p> 0.05).


CONCLUSIONS
These results suggest that the HFMOs in groups J and A produced significantly lower TMPDs and pre- and post-oxygenator extracorporeal circuit pressures during normothermic and hypothermic CPB.
Ji
Bingyang
B
Department of Cardiopulmonary Bypass, Fuwai Hospital & Cardiovascular Institute, Peking Union Medical College, Chinese Academy of Medical Science, Xi Cheng District, Beijing, China. dr.ji.cpb@gmail.com
Wang
Hongyue
H
Miao
Na
N
Xing
Jialin
J
Liu
Wei
W
Liu
Ruifang
R
Long
Cun
C
D000328:Adult; D000368:Aged; D001794:Blood Pressure; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000295:instrumentation*; D004867:Equipment Design; D006331:Heart Diseases / Q000097:blood / Q000503:physiopathology / Q000601:surgery*; D006400:Hematocrit; D006461:Hemolysis; D006801:Humans; D007036:Hypothermia, Induced; D008875:Middle Aged; D010107:Oxygenators, Membrane; D013997:Time Factors; D055815:Young Adult