Abstract 14039: The Cardioprotective and Anti-Inflammatory Effect of Inhaled Nitric Oxide During Fontan Surgery: A Prospective Randomized Study

Abstract

Introduction: Open heart surgery that requires cardiopulmonary by-pass (CPB) evokes tremendous stress and inflammatory responses, affecting postoperative organ function, morbidity, and mortality. Although part of this reaction triggers protective and anti-inflammatory phenomena, it is harmful, particularly in patients with single ventricle congenital heart defects during Fontan surgery. Unfortunately, there is no perfect anti-inflammatory and stress defence strategy despite decades of research. Hypothesis: This study aimed to investigate the influence of nitric oxide (NO) inhaled directly into the oxygenator during CPB on a proteome profile of inflammatory cytokines, metabolic response markers, heart and lung protection indicators, and the early clinical outcomes. Methods: The study involved 115 patients randomized to the Fontan-NO group, receiving NO inhalation (n=48) and the Fontan group, not receiving NO (n=49). Eighteen patients were excluded from the study. The clinical data were prospectively analyzed. Proteome profiler essays were used for repeated measurements of investigated analytes. Results: Fontan-NO patients had significantly lower levels of lactate (p=0.04) and glucose (p=0.02), lower pulmonary artery pressure (p=0.03) and catecholamine index (p=0.042), shorter ventilatory support time (p=0.03) and ICU stay (p=0.04). Plasma factors analysis has shown a significantly higher concentration of interleukin-10, tissue inhibitor of metalloproteinase, prolactin, and angiopoietin and a lower concentration of interleukin-6, interleukin-8, interleukin-1β, granulocyte-macrophage colony-stimulating factor, pentraxin, matrix metalloproteinase-8, troponin-I, CK-MB, and insulin in Fontan-NO group. Multiple regression analysis revealed the influence of Il-6 and Il-8 on respiratory support time and ICU stay and the relationship between catecholamine index, duration of effusions, and indicators of myocardial damage. Conclusions: NO inhaled into the oxygenator during CPB can alleviate the inflammatory response, improve myocardial and lung protection, and reduce metabolic stress in patients with a single ventricle undergoing Fontan surgery. The observed effects can influence short-term clinical outcomes.