Comparison of hollow-fiber membrane oxygenators in terms of pressure drop of the membranes during normothermic and hypothermic cardiopulmonary bypass in neonates

The objective of this study was to investigate the effects of two hollow-fiber membrane oxygenators, the Capiox SX10 and the Lilliput 901, on pressure drop of the membranes during normothermic and hypothermic cardiopulmonary bypass (CPB) in neonates. Methods: Twenty-six congenital heart surgery patients (n=13 in each group) with a mean weight of 3 kg were included in this study. Pressure drops of the membranes, pre- and post-oxygenator extracorporeal circuit pressures (ECC) were recorded during normothermic CPB, hypothermic CPB (20°C) and after rewarming. There were no differences between the groups in mean arterial pressure, pump flow rate, temperature, duration of CPB, cross-clamp time or the severity of the surgical repairs. Results: Pressure drop of the Capiox SX10 oxygenator was significantly lower during normothermic (32±10 versus 55±16 mmHg, p <0.001), hypothermic (38±15 versus 72±18 mmHg, p <0.001) and post-rewarming (42±13 versus 72±21 mmHg, p <0.001) periods compared to the Lilliput oxygenator in the Capiox group, the pre-oxygenator ECC pressure was also significantly lower during normothermic CPB (142±27 versus 184±43 mmHg, p <0.01), hypothermic CPB (162±30 versus 199±38 mmHg, p <0.01) and after rewarming periods (172±32 versus 212±42 mmHg, p <0.01). Post-oxygenator pressures in the Capiox group were also lower than in the Lilliput group, but results were not statistically significant. Conclusions: These results suggest that the Capiox SX10 hollow-fiber membrane oxygenator produced significantly lower membrane pressure drops and pre- and post-oxygenator ECC during normothermic and hypothermic CPB. Thus, blood trauma with the Capiox during extracorporeal circulation may be significantly lower compared to the Lilliput. Further studies, including the level of complements, platelets, neutrophils and cytokines, with these oxygenators are warranted.