Zhendong Liu, Ning Wang, Min Chen, Hongyan Wang
Sustained intraoperative MAP <65 mmHg, particularly for ≥30 min, was associated with higher odds of postoperative ICU admission after adjustment for measured clinical and surgical factors. Findings remained consistent when hypotension depth and time-normalized burden were considered, but do not establish causality or an intervention threshold.
BACKGROUND: Intraoperative hypotension is associated with postoperative organ injury, but its relationship with postoperative intensive care unit (ICU) admission after gastrointestinal lumen cancer surgery remains uncertain.
METHODS: We conducted a retrospective cohort study using the INSPIRE perioperative database. Adults undergoing their first gastrointestinal lumen excision or resection, identified by ICD-10-PCS 0DB*/0DT* codes and a temporally aligned ICD-10-CM C15-C21 diagnosis, were included. The primary exposure was cumulative duration of mean arterial pressure (MAP) <65 mmHg, categorized as 0, >0 to <10, 10 to <30, and ≥30 min. Multivariable logistic regression adjusted for demographic, clinical, laboratory, and surgical factors. Secondary analyses characterized the empirical MAP measurement intervals, time-weighted area below MAP 65 mmHg, and hypotension burden normalized to the monitored, strict operation, and strict anesthesia windows.
RESULTS: Among 7,405 patients, 1,157 (15.62%) were admitted to the ICU. ICU admission rates were 7.15, 10.91, 15.25, and 32.01% across increasing exposure categories. In the complete-case expanded model (n = 6,045; 966 events), adjusted odds ratios were 1.02 (95% CI, 0.75-1.40), 1.29 (95% CI, 1.00-1.66), and 1.78 (95% CI, 1.36-2.33), respectively, compared with no exposure. Of 319,661 consecutive MAP intervals, 99.43% were 5 min. Each 50-mmHg·min increase in the area below MAP 65 mmHg was associated with an OR of 1.07 (95% CI, 1.04-1.10), and each 5-min/h increase in MAP <65 mmHg duration within the strict operation window with an OR of 1.14 (95% CI, 1.07-1.21); both p < 0.001.
CONCLUSION: Sustained intraoperative MAP <65 mmHg, particularly for ≥30 min, was associated with higher odds of postoperative ICU admission after adjustment for measured clinical and surgical factors. Findings remained consistent when hypotension depth and time-normalized burden were considered, but do not establish causality or an intervention threshold.