ALB and Hypoalbuminemia: Of the 842,672 patients in the ACS-NSQIP cohort, 148,478 (17.6%) had high-risk preoperative serum albumin concentration (≤3.4 g/dL; hereinafter referred to as hypoalbuminemia) and 694,194 (82.4%) had low risk preoperative serum albumin concentration.