Duration and magnitude of vasopressor support predicts poor outcome after infant cardiac operations

Area of Science:

• Pediatric Cardiac Surgery
• Critical Care Medicine
• Pharmacology

Background:

• The vasoactive inotrope score (VIS) quantifies vasopressor dose at a single time point.
• Current VIS lacks sensitivity in predicting adverse outcomes post-cardiac surgery.
• Improved prediction models are needed for postcardiac surgical infants.

Purpose of the Study:

• To develop and validate a novel score (VISindex) that incorporates vasopressor duration and magnitude.
• To compare the predictive performance of VISindex against the traditional maximum VIS (maxVIS).
• To enhance the sensitivity of VIS for predicting poor outcomes in infants undergoing cardiac operations.

Main Methods:

• Retrospective review of 244 infants (≤365 days) undergoing cardiopulmonary bypass for congenital cardiac operations (2002-2011).
• Hourly VIS calculation for the first 72 postoperative hours.
• Defined poor outcome as prolonged mechanical ventilation (≥6 days) or ICU length of stay (≥12 days).
• Developed VISindex by integrating time-dependent vasopressor data and compared its predictive accuracy (AUC) with maxVIS.

Main Results:

• The VISindex showed superior sensitivity in predicting prolonged mechanical ventilation (AUC, 0.85) compared to maxVIS (AUC, 0.80).
• VISindex also demonstrated improved prediction for intensive care unit length of stay (AUC, 0.84) versus maxVIS (AUC, 0.77).
• These findings were significant within the study population of infants undergoing cardiac surgery.

Conclusions:

• The VISindex effectively incorporates both magnitude and duration of vasopressor support.
• This enhanced score significantly improves the prediction of poor outcomes in infants post-cardiac surgery.
• VISindex offers a more sensitive tool for risk stratification in pediatric cardiac critical care.