title: Stratified meta-analysis of intermittent pneumatic compression of the lower limbs to prevent venous thromboembolism in hospitalized patients.
abstract: BACKGROUND
  Optimal thromboprophylaxis for patients at risk of bleeding remains uncertain. This meta-analysis assessed whether intermittent pneumatic compression (IPC) of the lower limbs was effective in reducing venous thromboembolism and whether combining pharmacological thromboprophylaxis with IPC would enhance its effectiveness.
  
  
  RESULTS
  Two reviewers searched MEDLINE, EMBASE, and the Cochrane controlled trial register (1966-February 2013) for randomized, controlled trials and assessed the outcomes and quality of the trials independently. Trials comparing IPC with pharmacological thromboprophylaxis, thromboembolic deterrent stockings, no prophylaxis, and a combination of IPC and pharmacological thromboprophylaxis were considered. Trials that used IPC <24 hours or compared different types of IPC were excluded. A total of 16 164 hospitalized patients from 70 trials met the inclusion criteria and were subjected to meta-analysis. IPC was more effective than no IPC prophylaxis in reducing deep vein thrombosis (7.3% versus 16.7%; absolute risk reduction, 9.4%; 95% confidence interval [CI], 7.9-10.9; relative risk, 0.43; 95% CI, 0.36-0.52; P<0.01; I(2)=34%) and pulmonary embolism (1.2% versus 2.8%; absolute risk reduction, 1.6%; 95% CI, 0.9-2.3; relative risk, 0.48; 95% CI, 0.33-0.69; P<0.01; I(2)=0%). IPC was also more effective than thromboembolic deterrent stockings in reducing deep vein thrombosis and appeared to be as effective as pharmacological thromboprophylaxis but with a reduced risk of bleeding (relative risk, 0.41; 95% CI, 0.25-0.65; P<0.01; I(2)=0%). Adding pharmacological thromboprophylaxis to IPC further reduced the risk of deep vein thrombosis (relative risk, 0.54; 95% CI, 0.32-0.91; P=0.02; I(2)=0%) compared with IPC alone.
  
  
  CONCLUSIONS
  IPC was effective in reducing venous thromboembolism, and combining pharmacological thromboprophylaxis with IPC was more effective than using IPC alone.
authors.affiliation: Department of Intensive Care, Royal Perth Hospital, University of Western Australia, Wellington Street, Perth, WA 6000, Australia. kwok.ho@health.wa.gov.au
authors.forename: Kwok M
authors.initials: KM
authors.lastname: Ho
authors.forename: Jen Aik
authors.initials: JA
authors.lastname: Tan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003131:Combined Modality Therapy; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D007297:Inpatients; D048228:Intermittent Pneumatic Compression Devices; D035002:Lower Extremity; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000453:epidemiology / Q000401:mortality / Q000517:prevention & control; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome; D054556:Venous Thromboembolism / Q000453:epidemiology* / Q000401:mortality / Q000517:prevention & control*
chemical_list: D005343:Fibrinolytic Agents
keywords: prevention & control; venous thromboembolism