JMIR Publications

ABSTRACT

Background Intraoperative hypotension (IOH) is an important risk factor for major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the IOH threshold in elderly patients remains controversial. We therefore explored an appropriate IOH threshold in elderly patients to decrease the risk of MACE. Methods This study involved elderly patients (age of ≥65 years) who underwent noncardiac surgery from January 2012 to August 2019. Univariate moving-average plots and multivariate restricted cubic splines were used to determine the IOH thresholds associated with an increased risk of MACE. The relationship between the IOH threshold and MACE was assessed using univariate and multivariate logistic regression analyses by three different hypotension exposure forms [duration, area, and time-weighted average mean arterial pressure (MAP)]. Stratification analysis was used to explore whether the association between the IOH threshold and the occurrence of postoperative MACE differed between the very old (≥80 years old) and old elderly. Results In total, 874 of 35,262 patients developed MACE. MAP below an absolute threshold of 70 mmHg was associated with MACE. When the IOH absolute threshold was 70 mmHg, the risk of MACE demonstrated a “dose-increasing” effect with changes in IOH exposure, and the risk of MACE was significantly increased when the duration lasted >15 min (odds ratio, 1.51; 95% CI, 1.22 to 1.88; p < 0.001). Stratified analysis did not reveal a statistically significant difference in the effect of this threshold on the incidence of postoperative MACE between very elderly and elderly patients. Conclusions For elderly non-cardiac surgery patients, intraoperative MAP should be maintained above 70 mmHg as much as possible to reduce the risk of postoperative MACE.