Predictors of severe postoperative anemia in patients undergoing bloodless gynecologic surgery: A retrospective cohort study
Younga Kwon, Hye Lim Jung, Hwisu Jung, Kyoung-Chul Chun, Young Ah Kim, Jae Whoan Koh, Jung Yeol Han, Dong Won HwangObjective
To evaluate perioperative outcomes and identify predictors of severe postoperative anemia among patients who declined allogeneic blood transfusion and underwent bloodless gynecologic surgery.
Methods
We retrospectively analyzed consecutive patients who declined allogeneic blood transfusion and underwent bloodless gynecologic surgery at Inje University Ilsan Paik Hospital between January 2011 and December 2025. Severe postoperative anemia was defined as a postoperative hemoglobin nadir <8.0 g/dL. Univariable and multivariable Firth penalized logistic regression analyses were performed to identify independent predictors. Two multivariable models distinguished preoperative predictors from perioperative explanatory factors. Generalized additive modeling and sensitivity analyses were additionally performed.
Results
Among 195 patients, severe postoperative anemia occurred in 18 (9.2%), and only one patient (0.5%) required allogeneic blood transfusion. In the preoperative model, lower preoperative hemoglobin was the only independent predictor of severe postoperative anemia (adjusted OR 0.48, 95% CI 0.33–0.65; P<0.001). In the perioperative model, lower preoperative hemoglobin (adjusted OR 0.46, 95% CI 0.31–0.65; P<0.001) and greater estimated blood loss (adjusted OR 1.38 per 100 mL, 95% CI 1.17–1.69; P<0.001) remained independently associated with severe postoperative anemia. Spline analysis demonstrated a monotonic inverse association between preoperative hemoglobin concentration and postoperative anemia risk.
Conclusion
Bloodless gynecologic surgery in patients who declined allogeneic blood transfusion was associated with favorable perioperative outcomes and minimal use of allogeneic transfusion. Preoperative hemoglobin was the strongest and clinically modifiable predictor of severe postoperative anemia, supporting early identification and optimization before surgery.