Accuracy of preoperative lung ultrasound score for the prediction of major adverse cardiac events in elderly patients undergoing HIP surgery under spinal anesthesia: The LUSHIP multicenter observational prospective study

Background and objective: We hypothesize that lung ultrasound scores (LUS) can help stratify the cardiac risk of elderly patients undergoing orthopedic surgery for hip fracture, adding value to the Revised Cardiac Risk Index (RCRI), the American Society of Anesthesiologists Physical Status (ASA-PS) and the National Surgical Quality Improvement Program Myocardial infarction and Cardiac arrest (NSQIP-MICA). Methods: Prospective, observational multicenter study of 11 Italian hospitals on patients aged >65 years with hip fractures needing urgent surgery. Subjects with major adverse cardiovascular events (MACE) in the previous 6 months or with ongoing acute heart failure were excluded. Trained anesthesiologists obtained preoperative LUS scores during preoperative evaluation. ROC curve analysis and comparison were used to evaluate test accuracy. Results: A total of 877 patients were enrolled in the study period. 108 MACE events occurred in 98 patients, with an overall incidence of 11.2%. LUS score was higher in complicated than non- complicated patients, 11.6 f 6.64 vs. 4.97 f 4.90 (p < 0.001). Preoperative LUS score >8 showed both better AUC (0.78) and accuracy (0.76) in predicting MACE than the RCRI scores (p < 0.001), MICA scores (p = 0.001) and ASA classes (p < 0.001). LUS sensitivity was 0.71, specificity was 0.76, negative predictive value was 0.95. LUS score >8 showed an OR for MACE of 5.81[95% CI 3.55-9.69] at multivariate analysis. 91 patients (10.4%) experienced postoperative pneumonia showing a preoperative LUS score higher in the non-pneumonia group, p < 0.001. Conclusions: The preoperative LUS score, with its high negative predictive value, could improve patients' risk stratification when used alone or add further value to the RCRI score.