Ultrafiltration of prime solution results in improved lung function after congenital heart surgery

Background: Ultrafiltration of prime solution has been shown to reduce low molecular weight proteins that deteriorate the systemic inflammatory response after cardiopulmonary bypass (CPB). We examined whether ultrafiltration of prime solution would improve postoperative lung function and reduce the release of chemical mediators. Methods: Thirteen infants (from 3 to 12 months old) undergoing ventricular septal defect repair were randomized to those with (group 2, n = 4) and without (group 1, n = 9) ultrafiltration of prime solution, in which blood and albumin were cleansed with lactated Ringer's solution by ultrafiltration before the initiation of CPB. Blood levels in bradykinin, C3a, C5a, IL-2, and IL-6 were measured at 4 different points from the initiation of CPB to the end of operation. Postoperative pulmonary gas exchange function was measured at multiple points. Results: C3a and IL-6 are all increased during CPB and there were no significant differences between the two groups. C5a and IL-2 were not detected in either group. Bradykinin was activated by CPB but decreased during bypass in all cases. There were no differences between the two groups with respect to bradykinin, C3a, and IL-6. After operation, pulmonary gas exchange function (arterial oxygen tension at inspired oxygen at 1.0) was significantly higher in group 2 (447.6 ± 46.5 mmHg) than in group 1 (262.1 ± 80.7 mmHg) (p = 0.001) 6 hours after the operation. Conclusion: Ultrafiltration of prime solution improves postoperative lung gas exchange function and has potential benefits in patients who are expected to have acute lung injury in congenital heart disease.