Use of a novel vasoactive-ventilation-renal score to predict outcomes after paediatric cardiac surgery

Abstract

OBJECTIVES: Prior studies have established peak postoperative lactate and the vasoactive-inotrope score (VIS) as modest predictors of outcome following paediatric cardiac surgery. We developed a novel vasoactive-ventilation-renal (VVR) score and aimed to determine if this index, which incorporates postoperative respiratory, cardiovascular and renal function, would more consistently predict outcome in this patient population. METHODS: We performed an Institutional Review Board-approved retrospective analysis of 222 infants at our institution less than 365 days old who underwent surgery for congenital heart disease at our centre from January 2009 to April 2013. The VVR score was calculated as follows: vasoactive-inotrope score + ventilation index + (change in serum creatinine from baseline × 10). For all patients, peak lactate and admission, peak, and 48 h VIS and VVR were recorded. RESULTS: For all outcome measures, areas under the curve for 48-h VVR were greater than its corresponding admission and peak values, VIS alone at all three time points and peak lactate. On multivariate regression, 48-h VVR was strongly associated with prolonged intubation [odds ratio (OR): 39.13, P <0.0001], significantly more so than 48-h VIS (odds ratio: 6.18, P <0.0001) and peak lactate (odds ratio: 2.52, P = 0.017). The 48-h VVR was also more significantly associated with prolonged use of vasoactive infusions, chest tube drainage and ICU and hospital stay when compared with VIS alone and peak lactate. CONCLUSIONS: The novel 48-h VVR was a robust predictor of outcome following paediatric cardiac surgery and outperformed the VIS and peak postoperative lactate.