Abstract
Day surgery is critical for efficient healthcare delivery, but delayed discharge remains a key quality metric. This study investigates perioperative blood index changes during transurethral ureteroscopic laser lithotripsy (TULL) and constructs a risk prediction model for delayed discharge. A retrospective analysis of 526 TULL day surgery patients (2017-2021) compared normal (n = 412) and delayed discharge groups (n = 114). Blood indicators (WBC, Hb, Lymph#, Mono#, Neut#, Eos#) and clinical variables were analyzed. Logistic regression and ROC curves evaluated predictive factors. Delayed discharge was linked to longer operation time (OR = 1.024) and higher urine WBC (OR = 1.001), while Mono# showed protective effects (OR = 0.127). The model achieved an AUC of 0.710 (95% CI: 0.637-0.787), with strong calibration. The model enables early identification of high-risk patients, guiding interventions to reduce delayed discharge and improve day surgery management.