Authors: Y Lamarche, D Sirounis, JG Abel, M Gao, L Ding, SV Lichtenstein

Reference: Can J Cardiol 2011; 27(5) Supplement S196 - Abstract 374

BACKGROUND: Several risk scoring systems can help predict surgical mortality and complications in cardiac surgery. Those systems have not been designed and are not validated in pa-tients admitted to an Cardiac Surgical Intensive Care Unit (CSICU) immediately after surgery.
METHODS: The British Columbia Cardiac Surgery Registry was used to build a model to identify predictors of thirty-day mortality after adult cardiac surgery. From January 2000 to December 2009, preoperative and intraoperative data from 30 500 patients operated in four hospitals were used to build a multiple logistic regressionmodel. Sixty percent of the patients were used in the derivation group. Forty percent of the patients were used as a validation group. Type of procedure was forced into the model whereas all other variable with a P value <0.05 were integrated into the final model. RESULTS: Mortality occurred in 2.6% of patients (n = 790). Preoperative factors identified in the model as predictors of operative mortality were age, female gender, emergency status, pulmonary hypertension, peripheral vascular disease, renal dysfunction, diabetes, peptic ulcer disease, history of alcohol abuse and refusal of blood products. Intraoperative risk factors included intraaortic balloon pump, ventricular assist device or ECMO leaving the operating room; presence of any intraoperative complication reported by the surgeon, the use of inotropes, high dose vasopressors, red blood cell transfusion and cardiopulmonary bypass time. When used after surgery, the model had C-statistics of 0.86 and 0.86 in the training and validation set, respectively. CONCLUSION: Preoperative and intraoperative variables could be used at admission to a CSICU to calculate a severity score predicting the surgical mortality. The score is simple, easy to use and was highly predictive in that population. External validation in other settings will be necessary. The score could be used to describe the acuity of patients after cardiac surgery in further cardiac surgical intensive care studies.