Association Between Postoperative Troponin Levels and 90 Days Mortality Among Patients Undergoing Non-Cardiac Surgery

Abstract

Background: Globally, the mortality of non-cardiac surgery patients within the first month is increasing. Monitoring troponin-I levels aids in early mortality risk identification. Hence, the objective of this study was to determine the association between increased postoperative troponin-I levels to 90-day mortality in non-cardiac surgery patients. Methods: This prospective longitudinal study was conducted at Liaquat National Hospital’s general surgery department from June to December 2018. A total of 188 patients aged 40-70 years receiving a general or regional anesthetic, and undergoing emergency/elective surgery with a ≥2 days hospital stays, a procedure time of ≥2 hours, or blood loss of more than 300ml were recruited using a non-probability consecutive sampling technique. Troponin-I levels were assessed 6 to 12 hours post-surgery, followed by a 90-day phone-based mortality check. Data was analyzed using SPSS v.22. The chi-square test and Fisher’s exact test were applied with a p-value <0.05 considered significant. Results: Among 188 patients, 11 (5.9%) had positive troponin-I levels, and 23(12.2%) had raised levels in the immediate postoperative period. In 90-day follow-up, 8(4.2%) patients expired, all within the first 5 days, with a significant association between mortality and surgery type (p=0.001). Post-operative troponin-I levels showed a strong association with mortality (p<0.001). The proportion of patients with raised or positive troponin I levels was significantly higher in emergency cases (p<0.001). No deaths occurred in patients with baseline troponin I levels. Conclusion: Monitoring postoperative troponin I levels can help physicians intervene promptly, potentially reducing mortality in non-cardiac surgery patients. Keywords: Troponin I, Mortality, Non-cardiac Surgery.