Practicability and quality of outpatient management of acute deep venous thrombosis

The purpose of this study was to review the practicability and quality of a standardized management approach of deep venous thrombosis (DVT) provided by private practices.

There were 152 consecutive patients and 156 episodes. We determined the patients' diagnoses with estimation of clinical probability, D-dimers, duplex ultrasound scan, and venography. Patients were treated on an outpatient basis on principle, with dalteparin, phenprocoumon, different modalities of external leg compression, and deliberate ambulation. We followed up at 4 weeks.

Proximal DVT was diagnosed in 101 episodes (65%). Results of the D-dimer test were false-negative in 6%, and venography was indicated in 15%. Calf vein thrombosis was found in 55 patients. Results of the D-dimer test were false-negative in 30%, and venography was required in 37%. Eleven patients were hospitalized (9 for thrombectomy or thrombolysis), and 145 episodes (93%) were treated according to our standardized approach (provided by the referring physicians alone in 43%). For 5 days, dalteparin was injected by the patients themselves or their relatives, in 78% of the cases. The international normalized ratio values were more than 2 in 88% of the cases, with no difference between providers. In all but two cases, external leg compression was applied immediately: a modified Unna's boot in 28% and compressing stockings in 72% (Sigvaris 503 in 91%; calf length in 100% of distal DVT, and 83% of proximal DVT). During follow-up, there was no clinical evidence of recurrence or progression, 1 possible pulmonary embolism, 1 injection site hematoma, and 1 hospitalization unrelated to the DVT.

Diagnosis of proximal DVT is straightforward, but calf DVT often requires venographic confirmation because of discrepancies among clinical probability, D-dimer estimation, and ultrasound scan. Outpatient treatment can be offered to patients who can comply with the regimen. The quality of anticoagulation is in accordance with published data, and compliance with external leg compression is almost perfect.