[Exercise versus immobilization in the treatment of acute deep vein thrombosis during different clot-organized stage: an animal experiment].

Objective: To evaluate the corresponding influence on pulmonary embolism incidence between immobilization and exercise in different stage of thrombus after acute deep vein thrombosis in rabbits.

Methods: Forty-eight New Zealand rabbits were randomly divided into three groups depending on the different organized stage of thrombus: the early, medium and later stage group.Each group was subdivided into two sub groups: the immobile and mobile subgroup. Rabbit modeling of deep vein thrombosis was made by ligating the right femoral vein. Among the early-stage group, rabbits of the immobile subgroup were fixed for 3 days, while that of the mobile subgroup were free to move for 3 days, then each was euthanized to extract the lungs for pathological examination. Among the medium-stage group, each of the immobile subgroup were fixed for 7 days, while the mobile subgroup ones were fixed for 3 days, then released free-moving for 4 days following the pathological extraction. Among the later-stage group, animals in the immobile subgroup were fixed for 14 days comparing the mobile subgroup fixed for 7 days and next free-moving for 7 days, then each was euthanized.

Results: Among the early-stage group, pulmonary embolism incidence (PEI) of the immobile and mobile subgroup was 4/8 vs.3/8, the pulmonary lobe embolism incidence (PLEI) was 17.5% (7/40) vs. 15.0% (6/40). Among the medium-stage group, PEI of the immobile and mobile subgroup was 3/8 vs. 2/8, PLEI was 37.5% (7/40) vs. 25.0% (10/40). Among the later-stage group, PEI of the immobile and mobile subgroup was 3/8 vs. 3/8, PLEI was 12.5% (5/40) vs. 15.0% (6/40). There was no statistical difference between immobilization subgroup and mobilization subgroup among different stage group.

Conclusion: On the premise of given anticoagulation treatment, early ambulation do not significantly increase pulmonary embolism incidence after acute deep vein thrombosis of lower extremity in rabbits.