Abstract: Objective: To evaluate the effects of risk-stratified closed-loop intervention on the prevention of Venous Thromboembolism (VTE) in patients after thoracic surgery, in order to provide evidence for VTE prevention and control. Methods: A convenience sampling was used to recruit 312 surgical patients from the department of thoracic surgery at a tertiary grade A hospital in Xining. Patients admitted from January to December 2024 were assigned to the control group and received conventional perioperative care, while those admitted from January to December 2025 were assigned to the intervention group and received a risk-stratified closed-loop intervention protocol. Differences in structure, process and outcome quality indicators between the two groups were compared. Results: The incidence of postoperative VTE in the intervention group was lower than that in the control group (1.28% vs 6.41%, P<0.05). The intervention group exhibited lower postoperative peak D-dimer and shorter postoperative length of hospital stay (P<0.05). Process quality indicators such as the completion rate of VTE risk assessment after admission were superior to those in the control group (P<0.05). Conclusion: The risk-stratified closed-loop intervention can improve the quality of VTE prevention and reduce the incidence of VTE in patients undergoing thoracic surgery.

Key words: Venous Thromboembolism; thoracic surgery; Donabedian Three-Dimensional Quality Theory; risk stratification; closed-loop intervention