**2. Mechanical methods of thromboprophylaxis and the role of combined thromboprophylaxis modalities**

Early and frequent mobilizitation of hospitalized patients at risk for VTE is an important part of patient care. However, many patients cannot be fully ambulatory early after surgery. Furthermore, the majority of hospital-associated, symptomatic thromboembolic events occur after patients have started to ambulate, and mobilization alone does not provide adequate thromboprophylaxis for hospital patients. Specific mechanical methods of thromboprophylaxis, which include graduated compression stockings (GCS), intermittent pneumatic compression (IPC) devices, and the venous foot pump (VFP), increase venous outflow and/or reduce stasis within the leg veins. Use of mechanical thromboprophylaxis is the preferred option for patients at high risk for bleeding. If the high bleeding risk is temporary, consideration should be given to starting pharmacologic thromboprophylaxis once this risk has decreased. Mechanical thromboprophylaxis may also be considered in combination with anticoagulant thromboprophylaxis to improve efficacy in patient groups for which this additive effect has been demonstrated(3,5,6). However, since they are not associated with bleeding, and some methods have demonstrated efficacy as DVT prevention in clinical trials, the use of mechanical prophylaxis in combination with pharmacological prophylaxis may be helpful in certain situations. For example, in major trauma patients who have a high risk of bleeding at presentation (as after head injury), we use mechanical prophylaxis initially followed by anticoagulant prophylaxis with LMWH when safe (5,6). This strategy could be adopted in any postoperative situation in which the initial risk of bleeding is high.
