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Background This study sought to determine if preoperatively measured high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) improve cardiac risk prediction in patients undergoing major non-cardiac surgery when compared to standard risk indices. Methods In this ancillary study to the Vitamins in Nitrous Oxide (VINO) trial, patients were included who had preoperative hs-cTnT and NT-proBNP measured (n=572). Study outcome was the incidence of postoperative myocardial infarction (MI) within the first three postoperative days. hs-cTn was considered elevated if >14 ng/L and NT-proBNP if >300 ng/L. Additional cutoff values were investigated based on ROC statistics. Biomarker risk prediction was compared to Lee’s Revised Cardiac Risk Index (RCRI) using standard methods and net reclassification index (NRI). Results The addition of hs-cTnT (>14 ng/L) and NT-proBNP (>300 ng/L) to RCRI significantly improved the prediction of postoperative MI (event rate 30/572 (5.2%), AUC ROC increased from 0.590 to 0.716 with a 0.66 NRI [95% CI 0.32 – 0.99] p<0.001). Using 108 ng/L as cutoff for NT-proBNP improved sensitivity compared to 300 ng/L (0.87 vs. 0.53). Sensitivity, specificity, positive and negative predictive value for hs-cTnT were 0.70, 0.60, 0.09 and 0.97, and 0.53, 0.68, 0.08, 0.96 for NT-proBNP. Conclusions The addition of cardiac biomarkers hs-cTnT and NT-proBNP to RCRI improves prediction of adverse cardiac events in the immediate postoperative period after major non-cardiac surgery. The high negative predictive value of preoperative hs-cTnT and NT-proBNP suggest usefulness as a “rule-out” test to confirm low risk of postoperative MI.

Background The incidence, prediction and mortality outcomes of intraoperative and postoperative cardiac arrest requiring cardiopulmonary resuscitation (CPR) in surgical patients are under investigated and have not been studied concurrently in a single study. Methods A retrospective cohort study was conducted using the American College of Surgeons National Surgical Quality Improvement Program data between 2008 and 2012. Firth's penalized logistic regression was used to study the incidence and identify risk factors for intraand postoperative CPR and 30-day mortality. simplified prediction model was constructed and internally validated to predict the studied outcomes. Results Among about 1.86 million non-cardiac operations, the incidence rate of intraoperative CPR was 0.03%, and for postoperative CPR was 0.33%. The 30-day mortality incidence rate was 1.25%. The incidence rate of events decreased overtime between 2008-2012. Of the 29 potential predictors, 14 were significant for intraoperative CPR, 23 for postoperative CPR, and 25 for 30-day mortality. The five strongest predictors (highest odd ratios) of intraoperative CPR were the American Society of Anesthesiologists (ASA) physical status, Systemic Inflammatory Response Syndrome (SIRS)/sepsis, surgery type, urgent/emergency case and anesthesia technique. Intraoperative CPR, ASA, age, functional status and end stage renal disease were the most significant predictors for postoperative CPR. The most significant predictors of 30-day mortality were ASA, age, functional status, SIRS/sepsis, and disseminated cancer. The predictions with the simplified five-factor model performed well and