LMWH ‘not superior’ to UFH for DVT prevention in intensive care
MedWire News: Multinational study results show that there is no significant difference in the rate of deep vein thrombosis (DVT) among critically ill patients receiving thromboprophylaxis with unfractionated (UFH) versus low molecular weight heparin (LMWH).
"The effects of thromboprophylaxis with LMWH, as compared with UFH, on venous thromboembolism (VTE), bleeding, and other outcomes are uncertain in critically ill patients," explain Deborah Cook (McMAster University, Hamilton, Ontario, Canada) and co-investigators.
The researchers therefore set up the Prophylaxis for Thromboembolism in Critical Care Trial (PROTECT) to compare the effect of the LMWH dalteparin with that of UFH on the rate of proximal leg DVT in critically ill patients.
They also looked at rates of pulmonary embolism (PE), VTE, bleeding, heparin-induced thrombocytopenia, and death among the patients.
In total, 3746 patients were randomly assigned to receive either subcutaneous dalteparin 5000 IU once daily plus placebo once daily (n=1873), or UFH 5000 IU twice daily (n=1873) during intensive care unit admission.
The researchers found that the rate of proximal leg DVT - diagnosed on compression ultrasonography - did not differ significantly between the patients who received dalteparin and those who received UFH, at 5.1% versus 5.8%, respectively.
There was also no significant difference between dalteparin and UFH in the rates of major bleeding (5.5% vs 5.6%) or in-hospital death (22.1% vs 24.5%).
In contrast, the proportion of patients with PE was significantly lower with dalteparin than with UFH, at 1.3% versus 2.3%, respectively.
This finding meant that 100 patients would need to undergo prophylaxis with dalteparin rather than UFH to prevent one case of PE.
"Among critically ill patients, dalteparin was not superior to UFH in decreasing the incidence of proximal DVT," write Cook and co-authors in the New England Journal of Medicine.
"It is possible that in a larger trial, such a difference might have been detected," they conclude.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Laura Dean