D-dimer for Early Diagnosis of Venous Thromboembolism after Total Knee Arthroplasty

Abstract

Objective: To evaluate the usefulness of D-dimer value for the early diagnosis of venous thromboembolism (VTE) after total knee arthroplasty (TKA)
Materials and Methods: TKA was performed in fifty-two patients with osteoarthritis. The patients were 16 males (17 joints) and 36 females (38 joints) with a mean age of 72 years (range 63-86 years) at the time of surgery. We performed pulmonary perfusion scintigraphy to diagnose pulmonary thromboembolism (PTE) on the day of surgery, pre-and post operation. The 1^st 4^th and 7^th day after operation, the D-dimer values were examined in the peripheral blood. The ultrasonography and venography on the lower extremities were also performed on the 4^th day to diagnose for deep vein thrombosis (DVT) . First, we divided the patients into two groups: 1) DVT negative patients as normal group, 2) DVT positive patients as DVT group, and compared the D-dimer values between the two groups. Following that, the patients of DVT positive were divided into two groups. 1) PTE positive or DVT which was existed above knee joint (severe thromboemborism group) . 2) DVT below knee joints (mild thromboemborism group) .
Results: The D-dimer values of normal group was 15.1±1.8μg/ml on the 1^st day, 8.9±0.7μg /ml on the 4^th day and 11.9±0.7 μg/ml on the 7^th day. The values of DVT group were 18.8±2.2 μg/ml on the 1st day, 13.4±1.7μg/ml on the 4^th day and 19.2±2.0μg/ml on the 7^th day. The values of 4^th and 7^th day were significantly difference between the two groups. The D-dimer values of mild thromboemborism group was 15.8±1.7μg/ml on the 1^st day, 9.45±1.3μg/ml on the 4^th day and 17.5±1.3μg/ml on the 7^th day. There were eight patients in severe and twenty-four in mild thromboemborism groups. The results of severe thromboemborism group were 27.7±6.8μg/ml on the 1^st day, 25.3±3.4μg/ml on the 4^th day and 24.9±6.2μg/ml on the 7^th day. There was statistically significant difference between severe thromboemborism group and other two groups on the 1^st, 4^th and 7^th day. The D-dimer value kept the high levels in the severe thromboemborism group until 7th day.
Conclusion: The D-dimer values were higher than normal limit on the 1^st day, became lower on the 4^th day and became higher again on the 7^th day in the normal and mild groups. In the severe group, however, the values was higher on the 1^st day compared to the normal and mild groups and it did not show the decreasing change until 7^th day. Therefore, the comparison of the D-dimer values on the 1^st and 4^th day was thought to be useful for early diagnosis of high risk VTE cases which have PTE or severe DVT.