Postoperative Vasoactive Exposure Patterns Associated With Mortality and Acute Kidney Injury

A prespecified substudy of the international SQUEEZE cohort examined whether postoperative vasoactive exposure patterns offered prognostic information beyond treatment duration after non-cardiac surgery. Of 25,672 adults, 6,676 (26.0%) received vasoactive infusions within seven postoperative days. Researchers used unsupervised k-means clustering based on infusion duration, cumulative vasoactive agent-days, and peak concurrent agent count, then assessed associations with 30-day mortality, acute kidney injury (AKI), and hospital length of stay using multivariable regression.

Four reproducible exposure patterns were identified. Adjusted 30-day mortality ranged from 9.7% in the low-burden pattern to 35.3% in the high-burden pattern, although mortality did not increase strictly across all patterns. Adjusted AKI risk increased from 28.0% to 56.0%. In covariate-adjusted models using the same complete-case cohort, discrimination was higher with exposure pattern than with duration alone (AUC 0.818 versus 0.795). Adding duration to pattern classification provided little further discrimination (AUC 0.819). Findings were consistent in a prespecified landmark analysis of exposure during postoperative days 0–1.

These findings suggest that treatment persistence and overall vasoactive burden may inform postoperative risk assessment beyond infusion duration alone. However, the observational associations do not establish that more intensive vasoactive therapy causes worse outcomes or that changing treatment based on these patterns improves outcomes. The available abstract reports an association with hospital length of stay but provides no numerical estimates.