Effetto della cardiochirurgia sui livelli plasmatici di vitamina C in una popolazione pediatrica: studio prospettico longitudinale

Background: Vitamin C (or ascorbic acid or ascorbate) is an essential water - soluble micronutrient, not synthetized by the human body. It has several pleiotropic effects on human body: it is a potent antioxidant, it improves immune function, it facilitates enteral uptake of non heme iron and the reduction of folic acid intermediates, it is a cofactor for the synthesis of collagen (wound healing), cortisol, catecholamines and carnitine. Cardiovascular surgery, especially when cardiopulmonary bypass (CPB) is used, can trigger an important oxidative stress and a potent systemic inflammatory response syndrome and some patients may develop low cardiac output syndrome (LCOS), a severe post-operative complication. Many studies have demonstrated a significant consumption of vitamin C in critically ill patients. No such studies have been done in a pediatric population. The primary aim of our study was to determine pre- and post-operative vitamin C plasmatic levels in children undergoing cardiac surgery. The secondary aim was to evaluate whether a vitamin C deficiency can affect the outcomes in the first 72 hours period after cardiac surgery. Materials and methods: A single-center cohort study has been conducted over a period of 15 months (May 2021-August 2022) in pediatric patients undergoing open heart surgery in our Pediatric Cardiac Surgery Unit in Padua. We excluded patients > 18 years of age and on ECMO/RRT before surgery. A blood sample was collected right before and after the surgery and vitamin C plasmatic level was measured using high performance liquid chromatography. Demographic information, clinical information, intraoperative and post-operative data were collected. Data from the 72 hours following the surgery were used to obtain the following composite outcomes: acute kidney injury (AKI), vasoactive inotropic score (VIS), LCOS, ventilator free days and ICU free days. Categorical data are expressed as percentages, continuous variables are expressed as mean ± standard deviation (SD) or median and [interquartile range]. One Way Anova Test analysis was applied for normal continuous variables, while Kruskal-Wallis analysis was used for not normal continuous variables to confront groups. Vitamin C pre- and post-operative values and the difference between them, were tested in a logistic univariate model to verify causal association with composite oucomes. Results are reported as odds ratios (OR) with associated 95% confidence intervals (CI). Results:/ conclusions:/