Summary
Ultrasound screening for deep vein thrombosis (DVT) after orthopedic surgery revealed
thrombosis in up to 30% of patients, but the clinical impact of screening for distal
thrombosis has not been established.
Three hundred and forty six patients after hip or knee replacement and postoperative
standard prophylaxis of 10 days low molecular weight heparin (LMWH) were randomized
to receive either prolonged prophylaxis with LMWH or postoperative ultrasound screening
for proximal and distal thrombosis. All thrombosis found in screening was treated.
Patients with a negative screening test did not receive any heparin after day 10.
The cumulative rate of proximal thrombosis and symptomatic pulmonary embolism until
day 35 postoperatively was determined.
In 174 screening patients, ultrasound found 55 cases of distal (31.6%) and 9 cases
of proximal (5.1%) in-hospital thrombosis. In 108 screening patients without thrombosis
at discharge 7 new distal (6.5%) and 6 new proximal (5.6%) thrombotic events occurred
by day 35. In 163 patients with prolonged prophylaxis, 33 cases of distal (20.2%)
and 7 cases of proximal (4,3%) thrombotic events occurred by day 35. The cumulative
rate of proximal events was 8,7% in the screening group and 4.3% in the prophylaxis
group (p=0.12).
In conclusion, ultrasound screening for thrombosis does not reduce the rate of proximal
thrombosis and symptomatic pulmonary embolism 35 days after hip or knee replacement
surgery.
Keywords
Ultrasound screening - venous thromboembolism - orthopedic surgery - prophylaxis