Lower Levels of Vitamin D Are Associated with Higher Vasoactive-Inotropic Scores in Major Cardiac Surgery

Background: The vasoactive-inotropic score (VIS) predicts unfavorable outcomes after cardiac surgery in both children and adults. In our adult population, we investigated whether preoperative levels of vitamin D can predict the VIS and whether both vitamin D and the VIS can predict adverse outcomes following major heart surgery. Methods: Between 1 October 2021 and 28 February 2022, 300 patients underwent major cardiac surgery at our institution. Eighty-three of them had their 25-OH vitamin D levels measured before surgery. For this cohort, we calculated the VIS based on doses of vasoactive and inotropic medications administered post-surgery. Utilizing receiver operating curves, the predictive accuracy of vitamin D levels and the VIS in predicting acute kidney injury was assessed. Results: The median age of the cohort was 66 (IQR 61-71) years, with 59% being male and a median BMI of 28.4 (IQR 25.2-31.6). The most common procedures were aortic valve replacement, mitral valve replacement, coronary artery bypass grafting, aortic valve and ascending aorta repair, and ASD correction. There was a significant difference in the postoperative VIS between patients with vitamin D deficiency, i.e., <20 ng/mL, and patients with vitamin D values > 20 ng/mL (3.5 vs. 1.3 p < 0.04). We also found a significant correlation between the VIS and the days of hospitalization (r = 0.335; p = 0.002), the days of stay in the intensive care unit (r = 0.547; p < 0.00001), and the mechanical ventilation time (r = 0.327; p = 0.025). Both vitamin D levels and the VIS predicted postoperative acute kidney injury (p < 0.05). Conclusions: Vitamin D deficiency is correlated with the VIS in adults undergoing major cardiac surgery. Both vitamin D levels and the VIS can predict unfavorable postoperative outcomes.