Effect of Cardiopulmonary Bypass on Selected Neutrophil Functions in Children With Cyanotic Congenital Heart Disease

Background: Cardiopulmonary bypass (CPB) is known to induce several pathogenic responses in cardiovascular surgery. Children suffering from cyanotic congenital heart disease (CCHD) have been assumed to have a deficiency in their defence mechanisms. The preoperative clinical condition (hypoxemia and circulation disorders) could initiate post CPB inflammatory response. The nature of the participation of neutrophils and its time course in the post CPB inflammatory response, however, is less clear. The aim of our study was to investigate alterations in expression of adhesion molecules and L-selectin on neutrophils, and soluble adhesion molecules levels in CCHD children.

Materials and methods: 23 infants and children with congenital heart disease, scheduled for primary corrective surgical repair; were enrolled. Expression of CD11b. CD18, and CD62L on neutrophils was determined by cytometry. Additionally, serum concentrations of soluble ELAM-1, L-selectin were measured using enzyme-linked immunoassay. Blood samples of children with CCHD were collected at the following times: before anaesthesia, at the initiation of CPB, after 30 minutes of CPB, at the end of CPB, and 24 hours and 72 hours after surgery.

Results: The expression of CD11b molecule on neutrophils was increased significantly at the start of CPB and returned to the baseline after 24 hrs. In all patients, preoperative CD11b expression on neutrophils correlated with hypoxemia. Reduced CD62L expression on neutrophils and soluble L-selectin concentration were observed at the end of CPB.

Conclusion: We conclude, that cardiac surgery with CPB has a suppressive effect on adhesion molecules expression in children with CCHD, These findings also suggest that the type of neutrophil response to cardiac surgery appears to depend on preoperative clinical condition.