Data-Driven Preoperative Hemoglobin Strata Predict Blood Transfusion and Surgical Complication Risk Following Total Shoulder Arthroplasty.

INTRODUCTION

Preoperative anemia is associated with postoperative surgical complications and blood transfusions following total shoulder arthroplasty (TSA). However, hemoglobin thresholds have not been well identified. This study aimed to create data-driven preoperative hemoglobin levels that characterize the risk of blood transfusion and other medical and surgical complications.

METHODS

Patients who underwent TSA with a hemoglobin value recorded one month before surgery were identified from the TriNetX database. Stratum-specific likelihood ratio (SSLR) analysis defined preoperative hemoglobin cut-offs associated with increased 90-day postoperative blood transfusions for men and women. Additional outcomes included 90-day medical complications such as blood transfusion, major complications, wound infection, or dehiscence and 2-year surgical outcomes including all-cause revision, periprosthetic joint infection (PJI), and mechanical loosening.

RESULTS

The SSLR analysis identified four hemoglobin strata with increased 90-day blood transfusion for men (<12, 12-13, 13-14.5, >14.5 g/dL) and five hemoglobin strata for women (<10, 10-11, 11-12, 12-13, >13 g/dL). When comparing against the highest-value strata, there were sequential, significant increases in risk for 2-year PJI, 90-day major complications, and 90-day infection/wound disruption, progressing down the hemoglobin strata for both cohorts.

CONCLUSION

SSLR analysis characterized the likelihood of 90-day blood transfusions associated with hemoglobin strata, ranging from 0.24 to 4.65 for men and 0.23 to 8.11 for females, where intermediate strata had a LR close to 1, thus minimally changing the likelihood of transfusion. After matching, we observed a progressive increase in 90-day major medical complications (up to 1.84 and 2.2 times for men and women, respectively), 90-day infection/wound disruption (up to 3.14 and 3.71 times), and 2-year PJI (up to 2.36 and 4.94 times). These findings indicate that progressively lower preoperative hemoglobin is associated with a step-wise increase in postoperative TSA complication risk.

LEVEL OF EVIDENCE: Level III, Retrospective Cohort Comparison using Large Database, Prognosis Study.