Integrating continuous monitoring and evaluation of risk-adjusted outcomes in a cardiac surgical program

The variable life-adjusted display (VLAD) method shows the difference between predicted and observed outcomes over time. Our study aims to implement routine in-house monitoring of risk-adjusted 30-day mortality and morbidity following cardiac surgery.

The Society of Thoracic Surgeons (STS) risk score was calculated for 249 isolated and combined coronary and aortic or mitral valve cases performed during a 6-month period. The nine predicted STS variables were operative mortality, permanent stroke, renal failure (RF), prolonged ventilation, deep sternal wound (DSW) infection, reoperation for any reason, short and long length of stay (LOS), and major morbidity or operative mortality. EuroSCORE II was also calculated for the study population. VLAD plots were generated for each variable indicating whether performance is better or worse than expected on the basis of predicted risk of failure.

The mortality plot was fluctuating close to baseline risk. The prolonged ventilation, RF, reoperation, morbidity/mortality, and LOS plots were consistently positive, indicating favorable results. The stroke chart showed an upward trend for most of the period until two incidents toward last month led to a steep descent. The DSW infections plot though, indicated a worse-than-expected performance. The VLAD charts were shared in multidisciplinary meetings and clinicians were able to confront the performance with the population-specific expectancies and respond to adverse trends with further actions.

Graphical tool monitoring of risk-adjusted 30-day mortality and morbidity following cardiac surgery is feasible and allows detection of underperformance and implementation of changes in clinical practice.