Glycocalyx Degradation and Inflammation in Cardiac Surgery

Abstract

Objective: Experimental inflammation induces degradation of glycocalyx. The authors hypothesized that inflammation is an important determinant of glycocalyx degradation in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB).

Design: A prospective observational study.

Setting: Operation theater and intensive care unit of a university hospital.

Participants: Two separate prospective patient cohorts.

Interventions: Blood samples were collected at 5 perioperative time points in the trial cohort (30 patients) and only preoperatively in the preoperative cohort (35 patients). Plasma syndecan-1 (biomarker of glycocalyx degradation), interleukin-6 (IL-6), IL-8, and IL-10 were measured.

Measurements and main results: In the trial cohort, preoperative ranges were as follows: 0.8-198 ng/mL for syndecan-1; 0-902 pg/mL for IL-6; 0-314.9 pg/mL for IL-8, and 0-2,909 pg/mL for IL-10. Seven out of 30 patients were outliers in terms of plasma concentrations of syndecan-1 and all cytokines preoperatively. The increase of syndecan-1 was 2.7-fold, and those of IL-6 and IL-8 were both 2.5-fold. The increase of IL-10 was modest. Plasma syndecan-1 correlated with all cytokines preoperatively (IL-6: R = 0.66, p < 0.001; IL-8: R = 0.67, p = 0.001; IL-10: R = 0.73, p < 0.001) as well as at 6 hours postoperatively (IL-6: R = 0.49, p = 0.006; IL-8: R = 0.43, p = 0.02; IL-10: R = 0.41, p = 0.03) and on the postoperative morning (IL-6: R = 0.57, p = 0.001; IL-8: R = 0.37, p = 0.06; IL-10: R = 0.51, p = 0.005) but not intraoperatively. The preoperative findings of the trial cohort could be confirmed in the preoperative cohort.

Conclusions: In patients undergoing cardiac surgery with CPB, inflammation in terms of proinflammatory cytokines IL-6 and IL-8 and anti-inflammatory cytokine IL-10 is associated with glycocalyx degradation measured as plasma syndecan-1 concentrations.

Keywords: cardiopulmonary bypass; glycocalyx; inflammation; interleukin 10; interleukin 6; interleukin 8; syndecan-1.