Systemic inflammatory response during cardiopulmonary bypass: Axial flow versus radial flow oxygenators

Abstract

Background: The objective of this study was to investigate the inflammatory effects of different oxygenator flow pattern types in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass. Methods: We designed this randomized, single-blind, prospective study of patients with coronary artery disease. We compared the systemic inflammatory effects of oxygenators with two types of flow: axial flow and radial flow. Therefore, we divided the patients into two groups: 24 patients in the axial group and 28 patients in the radial group. IL-1, IL-6, IL-10, and TNF-α were examined for cytokine activation leading to a systemic inflammatory reaction. The samples were collected at three different time intervals: T1, T2, and T3 (T1 was taken before cardiopulmonary bypass, T2 just 1 h after CPB onset, and T3 was taken 24 h after the surgery). Results: There were no significant differences in demographic characteristics between the two groups. We observed that there were notably lower levels of humoral inflammatory response parameters (IL-1, IL-6, and TNF-α) in the radial flow oxygenator group than in the axial flow group at the specific sampling times. For IL-10, there was no significant difference for any time period. Conclusion: It might be advantageous to use a radial-flow-patterned oxygenator to limit the inflammatory response triggered by the oxygenators in cardiopulmonary bypass.