Early Rise of Inflammatory Mediators during Pediatric Cardiac Surgery with Cardiopulmonary Bypass: Implications for Perioperative Management

Background: Inflammation and immunosuppression following pediatric cardiac surgery with cardiopulmonary bypass (CPB) are associated with significant morbidity. The intraoperative release of immune mediators is a key factor, and the elimination of these mediators is a target of immunomodulatory interventions during the perioperative period. However, the dynamics of inflammatory mediator release during surgery are still not fully understood.

Methods: Thirty-five children with various congenital heart diseases undergoing CPB surgery were prospectively included. Cytokine expression was measured longitudinally from blood samples taken preoperatively, 5 minutes after cannulation, before aortic cross-clamp release, and at the end of reperfusion using a multiplex bead array. Baseline plasma levels and ultrafiltrate effluent collected preoperatively and during reperfusion were analyzed accordingly.

Results: Of the 50 cytokines measured, 42 increased significantly, many by several log levels during surgery. Longitudinal analysis revealed fast kinetics with an early rise in most cytokines. Notably, 46 of the 50 cytokines showed a significant increase during aortic cross-clamping. Only 17 (IL-6, CXCL8/IL-8, CCL11/eotaxin, IL-16, SCF, CCL2/MCP-1, VCAM-1, CCL4/MIP-1b, CCL3/MIP-1a, IL-15, G-CSF, IL-1b, VEGF, ICAM-1, TRAIL, IL-10, and IL-1RA) continued to rise significantly during reperfusion. Interestingly, immunomodulatory mediators such as IL-10, and IL-1RA rose relatively strongly after the release of the cross-clamp. Zero-balanced ultrafiltration was applied throughout the CPB, but no significant differences in cumulative filtration volumes were observed between the cross-clamping and reperfusion phases. However, filtration properties varied among different cytokines, particularly at higher cytokine concentrations during surgery.

Conclusion: Pediatric cardiac surgery with CPB leads to a rise in soluble inflammatory mediators, most of which increase early and continuously during the procedure. The expected peak after aortic cross-clamp release was not observed. Strategies to eliminate immune mediators, such as ultrafiltration, may need to focus on the entire intraoperative period.

Publication History

Article published online:
11 February 2025