Pneumatic compression in addition to pharmacologic thromboprophylaxis does not further reduce DVT risk

Reference

Arabi YM, Al-Hameed F, Burns KEA, et al, for the Saudi Critical Care Trials Group. Adjunctive intermittent pneumatic compression for venous thromboprophylaxis. N Engl J Med 2019;380(14):1305-1315.

Synopsis

Current guidelines recommend pharmacologic thromboprophylaxis in all critically ill patients. In this international multicenter study, researchers investigated whether the addition of mechanical thromboprophylaxis with intermittent pneumatic compression would further reduce the risk of DVT in these patients. Adult patients expected to be in the intensive care unit (ICU) for at least 72 hours were randomized, using concealed allocation, to receive pneumatic compression (n = 991) or pharmacologic thromboprophylaxis alone (n = 1012). Both groups received pharmacologic thromboprophylaxis with unfractionated heparin or low-molecular-weight heparin. In the pneumatic compression group, patients also received intermittent compression to both lower limbs for at least 18 hours per day. Although sequential compression devices with thigh-length sleeves were preferred, nonsequential devices and knee-length sleeves, as well as foot pumps, were permitted. In the control group, pneumatic compression was only permitted during times when pharmacologic thromboprophylaxis was interrupted. Proximal venous ultrasonography of the lower limbs was performed 48 hours after randomization and then twice weekly and if DVT was clinically suspected. The 2 groups were balanced at baseline: the mean age was 58 years, almost 80% of patients were medical admissions to the ICU, and two-thirds were receiving mechanical ventilation. The primary outcome of new proximal lower limb DVT did not differ significantly between the 2 groups (3.9% in the pneumatic compression group vs 4.2% in the control group; relative risk 0.93; 95% CI 0.60 - 1.44; P = .74). Additionally, there were no significant differences detected in any secondary outcomes, including pulmonary embolisms, death, or skin injuries related to pneumatic compression. Given that the incidence of DVT in the control group was lower than an expected 7%, this trial was underpowered to detect a difference if it truly exists.