Abstracts of Posters Presented at the International Anesthesia Research Society; 72nd Clinical and Scientific Congress; Orlando, FL; March 7-11, 1998: Cardiovascular Anesthesia
Introduction: Cardiopulmonary bypass (CPB) is characterized by systemic endotoxemia with proinflammatory cytokine production, including interleukin IL-6 (IL-6). IL-6 plasma levels are the best cytokine marker for post CPB myocardial ischemic episodes, wall motion abnormality scores, and systemic vascular resistance reduction . Serum lipids, especially high density lipoprotein (HDL), bind (neutralize) endotoxin (LPS), thereby reducing LPS-induced monocyte IL-6 release . This study correlates preoperative plasma HDL levels with the post-CPB IL-6 response in humans.
Methods: After IRB approval and patient consent, plasma levels of IL-6 were measured in 15 adults at baseline, 1 and 24 hrs post-CPB by ELISA. Patients were matched for variables known to influence post-CPB IL-6 levels (durations of aortic cross clamp and total CPB, LV ejection fraction, temperature during CPB, avoidance of anti-inflammatory drugs and blood products) in order to isolate HDL concentrations as an independent predictor of CPB-induced IL-6 release. Spearman Correlation Coefficients were used to determine significance.
Results: IL-6 plasma levels increased at 1 and 24 hr post-CPB when compared to baseline (p<.05) (Figure 1). IL-6 levels correlated inversely at 1 hr post-CPB with preoperative plasma concentrations of HDL (p=.02) (Figure 2).
Discussion: These results demonstrate plasma HDL concentrations have an antiinflammatory effect during CPB and may partly explain the marked interpatient variability of IL-6 levels post-CPB previously reported by others .
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© 1998 International Anesthesia Research Society
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