A Study of Coagulation Changes at Early Stage after Total Knee Arthroplasty

Abstract

Coagulation changes after total knee arthroplasty (TKA) can provide evidence for optimization of timing of perioperative anticoagulation medicine. To evaluate the changes, 50 patients with knee osteoarthritis or rheumatoid arthritis were recruited for the study and underwent thrombelastography tests pre-, 6 hours, 12 hours, and 24 hours after TKA surgery and Doppler ultrasound examination 20 to 24 hours after surgery. The results have shown prolonged clotting time ( value) at 6 and 12 hours, while shortened at 24 hours. Similar results have been found in combined clotting and coagulation time ( + value). However, other parameters, such as coagulation time ( value), coagulation speed ( angle), maximum amplitude (MA), and coagulation index (CI), have not significantly changed except that CI has increased significantly at 24 hours. Further Doppler ultrasound examination did not detect any deep venous thrombosis in all patients. The data showed that coagulation time after TKA within 12 hours, especially within the 6-hour time period, after surgery was significantly higher, while at 24 hours it became lower than the preoperation time. The results suggested that anticoagulation medicine is not necessary during the first 6 to 12 hours, but is required between 12 and 24 hours after surgery to reduce the risk of thrombosis.

Thromboelastography for the Prevention of Perioperative Venous Thromboembolism in Orthopedics

“…49 Huang et al also used TEG to test the changes in coagulation function within 24 h after total knee replacement. 50 Although the data obtained by the two groups were slightly different at approximately 24 h, the conclusions of these studies were similar. They believed that most coagulation functions of patients after joint replacement were in a low coagulation state within 24 h after the operation.…”

“…Aspirin (ASA), an inhibitor of cyclooxygenase-1 (COX-1), reduces thrombosis by irreversibly inhibiting platelet aggregation and inhibits intimal hyperplasia. 50 , 63 In an experiment to explore the perioperative medication safety of ASA, Li et al found that during the perioperative period of posterior lumbar fusion, compared with the aspirin-free group (Group 2), the R and K of patients in the aspirin-extended group (Group 1) were relatively increased and MA and α-angles were relatively decreased, and they were not statistically significant. This conclusion is consistent with the outcomes of CCT of patients in the two groups and confirmed with the incidence of objective events.…”