[Detection of asymptomatic venous thrombosis after lower limb prosthetic surgery. Retrospective evaluation of a systematic approach using Doppler ultrasonography: 400 cases].

OBJECTIVES: The purpose of this study was to evaluate a pragmatic approach using duplex ultrasonography (US) for detecting deep vein thrombosis (DVT) after total hip (THA) and total knee (TKA) replacement.

METHODS: Venous B-mode and color duplex US examination of both legs including a systematic evaluation of calf veins was performed twice during hospital stay (Between day 1 and day 4 for the first exam and between day 7 and day 11 for the second) in 400 consecutive patients.

RESULTS: Deep vein thrombosis was diagnosed in 53 patients (13.5%) including 7 patients with proximal DVT. Thrombosis was asymptomatic in 46 patients (85%), and was bilateral or concerned the non-operated leg in 8 patients (14.5%). No clinical pulmonary embolism (PE) occurred during hospital stay (mean hospital stay: 12.3). Prior phlebitis and age over 70 were identified as a statistically significant risk-factor for post-operative DVT (p = 0.001 and p < 0.01 respectively) concerning the whole series and the THA series (p < 0.02 and p < 0.04 respectively). No statistically significant risk factor was founded for the TKA series (p < 0.2 and p < 0.2 respectively). All patients were seen at three months. Four patients (1.16%) developed DVT between hospital discharge and the 3-month follow-up visit. One patient with coronary disease died suddenly on post-operative day 24, without clinical signs or symptoms of PE or DVT.

CONCLUSION: Venous US performed twice after total hip replacement detected asymptomatic DVT in 85% of patients. This approach might explain the absence of PE in our series and thus justify systematic ultrasonographic evaluation of lower limb veins after prosthetic replacement.