A Combination of N-Terminal proB-Type Natriuretic Peptide and Myoglobin Can Predict Severe Complications After Major Non-Cardiac Surgery in Elderly Patients: A Prospective Observational Cohort Study

Background: Previous studies have demonstrated that serum N-terminal proB-type natriuretic peptide (NT-proBNP) was a predictor of adverse cardiovascular outcomes after surgery. We performed a prospective study to evaluate if NT-proBNP could be a sensitive marker of overall postoperative outcomes in older patients undergoing major elective non-cardiac surgery when combined with myoglobin (MYO). Methods: Two hundred and three adults aged ≥65 years were enrolled in the study. The American Society of Anesthesiologists (ASA) physical status of patients were I to IV. Blood samples would be taken before and 2 h after the surgery for each patients and NT-proBNP and MYO concentrations (NT-proBNP baseline/ 2 h and MYO baseline/ 2 h) of these samples would be measured immediately. The primary outcome was moderate to severe complications, which were based on the Clavien–Dindo Classification (CDC) scheme (≥CDC grade 3), and the secondary outcomes were major complications within 30 days after surgery. This study was registered at China Clinical Trial Registry (ChiCTR1900026223, http://www.chictr.org.cn/). Results: Overall, moderate to severe complications occurred in 15 patients (7.4%) and major complications occurred in 18 patients (8.9%). Both preoperative and postoperative NT-proBNP values were independent predictors of moderate to severe complications (area under the curve (AUC), 0.820; 95% CI: 0.728, 0.912, P < 0.001; AUC, 0.785; 95% CI: 0.685, 0.885, P < 0.001). When NT-proBNP baseline and MYO-2 h were combined (NT-proBNP baseline × MYO-2 h), the predictive power was improved (AUC 0.841, 95% CI: 0.758, 0.923, P < 0.001). Conclusions: A combination of perioperative NT-proBNP and postoperative MYO concentrations was a good predictor of postoperative complications in elderly patients who underwent major non-cardiac surgery. Using fast and dynamic tests provided by point-to-care-testing, NT-proBNP and MYO concentration measurements provided useful guidance for therapy before or soon after surgery, thus helping to reduce postoperative complications in elderly patients.