Prospective validation of vasoactive-inotropic score (VIS) and inotrope score (IS) in infants after cardiovascular surgery
Prospective observational study of 70 infants (≤90 days of age) undergoing cardiothoracic surgery. VIS and IS were assessed at 24 (VIS24, IS24), 48 (VIS48, IS48), and 72 (VIS72, IS72) hours after surgery. Maximum VIS and IS scores in the first 48 hours were also calculated (VIS48max and IS48max). The primary outcome was length of intubation. Additional outcomes included length of intensive care (ICU) stay and hospitalization, cardiac arrest, mortality, time to negative fluid balance, peak lactate, and change in creatinine.
Based on Receiver Operating Characteristic (ROC) analysis, area under the curve (AUC) was highest for VIS48 to identify prolonged intubation time. AUC for the primary outcome was higher for VIS than IS at all time points assessed. On multivariate analysis VIS48 was independently associated with prolonged intubation (OR 22.3, p=0.002), prolonged ICU stay (OR 8.1, p=0.017), and prolonged hospitalization (OR 11.3, p=0.011). VIS48max, IS48max, and IS48 were also associated with prolonged intubation, but not prolonged ICU or hospital stay. None of the scores were associated with time to negative fluid balance, peak lactate, or change in creatinine.
In neonates and infants, a higher VIS at 48 hours after cardiothoracic surgery is strongly associated with increased length of ventilation, and prolonged ICU and total hospital stay. At all time points assessed, VIS is more predictive of poor short term outcome than IS. VIS may be useful as an independent predictor of outcomes.