Doppler ultrasonography-aided early diagnosis of venous thromboembolism after total knee arthroplasty.

ABSTRACT

OBJECTIVES: Postoperative deep venous thrombosis (DVT) is usually asymptomatic but can result in a fatal pulmonary embolism (PE). To assess the ability of transcranial Doppler (TCD) ultrasound apparatus to detect venous emboli in patients who had undergone total knee arthroplasty (TKA). METHODS: Forty-eight patients undergoing TKA were examined postoperatively by using compression ultrasonography, computed tomographic angiography, and TCD ultrasonography that detected high-intensity transient signals (HITS) in femoral veins. An original scoring system based on both the number of HITS and the locations of DVT was tested for its accuracy in predicting PE development. RESULTS: Twenty-three of the 48 patients had DVT postoperatively, and 8 had an asymptomatic PE. The sensitivity and specificity of the HITS assessment alone in identifying PE development were 75% and 92.5%, respectively. The scoring system, however, had a sensitivity of 100% and a specificity of 85% and the area under the receiver operating characteristic (ROC) curve (AUC) was 0.96. CONCLUSIONS: Application of a scoring system based on the detection of both DVT and HITS may be an effective and efficient method of screening for PE after knee arthroplasty.