To verify the sensitivity of D-dimer concentration monitoring to the occurrence of DVT after hip arthroplasty, and to determine the optimal blood collection time for D-dimer measurement.

A total of 60 patients undergoing hip replacement from March 2017 to 2018 in our hospital were collected and the concentrations of D-dimer were measured before operation. Color Doppler ultrasonography of the lower extremities were used to exclud DVT, patients with D-dimer mass concentration > (age×10) g/L were divided into positive group and the rest were negative group. Postoperative monitoring of D-dimer mass concentration was followed by color Doppler ultrasonography. The BMI index, age, surgical bleeding volume, gender, and the concentration of D-dimer at 1 d, 3 d, 5 d, 9 d and 14 d before and after surgery were statistically analyzed.

The concentrations of D-dimer in the positive group at 1 d, 3 d, 5 d, 9 d and 14 d were (1,700±124) μg/L, (2,318±246) μg/L, (1,985±435) μg/L, (1,752.3±221.3) μg/L, (1,322±158) μg/L, respectively. D-dimerization of the negative group were (343±98) μg/L, (372±79) μg/L, (356±59) μg/L, (345±76) μg/L and (226±102) μg/L, respectively. The concentration of D-dimer in the positive group was significant higher than that in the negative group (P<0.05). 2 cases of the positive group were found DVT and patients in negative group remained 500 g/L below.

The change of D-dimer concentration is sensitive to DVT, The peak of D-dimer concentration on the 3rd day after operation was the best time to predict DVT.