Postoperative complications increase hospital length of stay and patient mortality.

Optimal perioperative fluid management should decrease patient complications.

This study examined associations between fluid volume and noncardiac surgery patient outcomes within a large multicentre US surgical cohort.

Adults undergoing noncardiac procedures from January 1, 2012 to December 31, 2017, with a postoperative length of stay ≥24 h, were extracted from a large US electronic health record database.

Patients were segmented into quintiles based on recorded perioperative fluid volumes with Quintile 3 (Q3) serving as the reference.

The primary outcome was defined as a composite of any complications during the surgical admission and a postoperative length of stay ≥7 days.

Secondary outcomes included in-hospital mortality, respiratory complications, and acute kidney injury.