A multicentre controlled pre-post trial of an implementation science intervention to improve venous thromboembolism...

To test whether a multicomponent intervention would increase the use of low molecular weight heparin (LMWH) over unfractionated heparin (UFH) for venous thromboembolism (VTE) prophylaxis in critically ill patients and change patient outcomes and healthcare utilization.

Controlled pre-post trial of 12,342 adults admitted to 11 ICUs (five intervention, six control) May 1, 2015 to April 30, 2017 with no contraindication to pharmacological prophylaxis and an ICU stay longer than 24 h. Models were developed to examine temporal changes in ICU VTE prophylaxis (primary outcome), VTE, major bleeding, heparin-induced thrombocytopenia (HIT), death and hospital costs.

The use of LMWH increased from 45.9% to 78.3% of patient days in the intervention group and from 37.9% to 53.3% in the control group, an absolute increase difference of 17.0% (32.4% vs. 15.4%, p = 0.001). Changes in the administration of UFH were inversely related to those of LMWH. There were no significant differences in the adjusted odds of VTE (ratio of odds ratios [rOR] 1.13, 95% CI 0.51-2.46) or major bleeding (rOR 1.22, 95% CI 0.97-1.54) post-implementation of the intervention (compared to pre-implementation) between the intervention group and the control group. HIT was uncommon in both groups (n = 20 patients). There were no significant changes for ICU and hospital mortality, length of stay and costs. Results were similar when stratified according to reason for ICU admission, patient weight and kidney function.

A multicomponent intervention changed practice, but not clinical and economic outcomes. The benefit of implementing LMWH for VTE prophylaxis under real-world conditions is uncertain.