The Safety of Low-Molecular-Weight Heparin Bridging Therapy in Patients Receiving Preoperative Oral Antithrombotic Drugs During Spinal Fusion Surgery

【Purpose】 To evaluate whether preoperative oral antithrombotic drugs increase perioperative bleeding risk in spinal fusion patients receiving low-molecular-weight-heparin (LMWH) bridging therapy, and compare bleeding risk with general patients. 【Methods】 Patients who underwent spinal fusion (2019–2024) at two hospitals were grouped: Oral Anticoagulation gourp (history of preoperative antithrombotic drugs + LMWH bridging), No Oral Anticoagulation group (without history of preoperative antithrombotic drugs + LMWH), and Blank group (matched to Oral Anticoagulation group, no perioperative anticoagulation). Primary outcome: severe bleeding events. Secondary outcomes: intraoperative blood loss, transfusion rates, and coagulation markers. Statistical analyses included t-test, Mann-Whitney U test, and repeated measures ANOVA. 【Results】 73 patients were enrolled (Oral Anticoagulation group: 42, No Oral Anticoagulation group: 31, Blank group: 42). Oral Anticoagulation group had higher intraoperative blood loss, transfusion rate, and longer hospital stay vs Blank group (p < 0.05). In lumbar surgery, Oral Anticoagulation group showed significantly higher intraoperative/overt blood loss vs No Oral Anticoagulation group (p < 0.05), but no difference showed in cervical surgery. No severe bleeding events (e.g., intraspinal hematoma) occurred in any group. 【Conclusion】 Preoperative oral antithrombotic drugs with LMWH bridging did not increase severe bleeding risk in spinal fusion, but elevated intraoperative bleeding and transfusion rates, particularly in lumbar surgery.