Thrombosis prophylaxis and mortality risk among critically ill adults.

BACKGROUND

The optimal approach for managing increased risk of VTE among critically ill adults is unknown.

METHODS

An observational study of 294,896 episodes of critical illness among adults was conducted in 271 geographically dispersed US adult ICUs. The primary outcomes were all-cause ICU and in-hospital mortality after adjustment for acuity and other factors among groups of patients assigned, based on clinical judgment, to prophylactic anticoagulation, mechanical devices, both, or neither. Outcomes of those managed with prophylactic anticoagulation or mechanical devices were compared in a separate paired, propensity-matched cohort.

RESULTS

After adjustment for propensity to receive VTE prophylaxis, APACHE (Acute Physiology and Chronic Health Evaluation) IV scores, and management with mechanical ventilation, the group treated with prophylactic anticoagulation was the only one with significantly lower risk of dying than those not provided VTE prophylaxis (ICU, 0.81 [95% CI, 0.79-0.84]; hospital, 0.84 [95% CI, 0.82-0.86; P < .0001). The mortality risk of those receiving mechanical device prophylaxis was not lower than that of patients without VTE prophylaxis. A study of 87,107 pairs of patients matched for propensity to receive VTE prophylaxis found that those managed with prophylactic anticoagulation therapy had significantly lower risk of death (ICU subhazard ratio, 0.82 [95% CI, 0.78-0.85]; hospital subhazard ratio, 0.82 [95% CI, 0.79-0.85]; P < .001) than those receiving only mechanical device prophylaxis.

CONCLUSIONS

These findings support a recommendation for prophylactic anticoagulation therapy in preference to mechanical device prophylaxis for critically ill adult patients who do not have a contraindication to anticoagulation.