Vasoactive Inotropic Score (VIS) as Biomarker of Short-Term Outcomes in Adolescents after Cardiothoracic Surgery

Our aim was to evaluate the Vasoactive Inotropic Score (VIS) as a prognostic marker in adolescents following surgery for congenital heart disease. This single-center retrospective chart review included patients 10-18 years of age, who underwent cardiac surgery from 2009 to 2014. Hourly VIS was calculated for the initial 48 postoperative hours using standard formulae and incorporating doses of six pressors. The composite adverse outcome was defined as any one of death, resuscitation or mechanical support, arrhythmia, infection requiring antibacterial therapy, acute kidney injury or neurologic injury. Surgeries were risk-stratified by the type of surgical repair using the validated STAT score. Statistical analysis (SPSS 19.0) included Mann-Whitney U test, Chi-square test, ROC curves, and binary regression analysis. Our cohort (n = 149) had a mean (SD) age of 13.9 (2.4) years and included 97 (65.1 %) males. Maximal VIS at 24 and 48 h following surgery was significantly higher in subjects (n = 27) who suffered an adverse outcome. Subjects with adverse outcome had longer bypass and cross-clamp times, durations of stay in the hospital, and a higher rate of acute kidney injury, compared to those (n = 122) without postoperative adverse outcomes. The area under the ROC for maximum VIS at 24-48 h after surgery was 0.76, with sensitivity, specificity, and positive and negative predictive values with 95 % CI of 67 (48-82) %, 74 (70-77) %, and 36 (26-44) % and 91 (86-95) %, respectively, at a cutoff > 4.75. On binary logistic regression, maximum VIS on second postoperative day remained significantly associated with adverse outcome (OR 1.35; 95 % CI > 1.12-1.64, p = 0.002). Maximal VIS at 24 and 48 h correlated significantly with length of stay and time to extubation. Maximal VIS on the second postoperative day predicts adverse outcome in adolescents following cardiac surgery. This simple yet robust prognostic indicator may aid in risk stratification and targeted interventions in this population.