title: Outpatient versus inpatient treatment for patients with acute pulmonary embolism: an international, open-label, randomised, non-inferiority trial.
abstract: BACKGROUND
  Although practice guidelines recommend outpatient care for selected, haemodynamically stable patients with pulmonary embolism, most treatment is presently inpatient based. We aimed to assess non-inferiority of outpatient care compared with inpatient care.
  
  
  METHODS
  We undertook an open-label, randomised non-inferiority trial at 19 emergency departments in Switzerland, France, Belgium, and the USA. We randomly assigned patients with acute, symptomatic pulmonary embolism and a low risk of death (pulmonary embolism severity index risk classes I or II) with a computer-generated randomisation sequence (blocks of 2-4) in a 1:1 ratio to initial outpatient (ie, discharged from hospital ≤24 h after randomisation) or inpatient treatment with subcutaneous enoxaparin (≥5 days) followed by oral anticoagulation (≥90 days). The primary outcome was symptomatic, recurrent venous thromboembolism within 90 days; safety outcomes included major bleeding within 14 or 90 days and mortality within 90 days. We used a non-inferiority margin of 4% for a difference between inpatient and outpatient groups. We included all enrolled patients in the primary analysis, excluding those lost to follow-up. This trial is registered with ClinicalTrials.gov, number NCT00425542.
  
  
  RESULTS
  Between February, 2007, and June, 2010, we enrolled 344 eligible patients. In the primary analysis, one (0·6%) of 171 outpatients developed recurrent venous thromboembolism within 90 days compared with none of 168 inpatients (95% upper confidence limit [UCL] 2·7%; p=0·011). Only one (0·6%) patient in each treatment group died within 90 days (95% UCL 2·1%; p=0·005), and two (1·2%) of 171 outpatients and no inpatients had major bleeding within 14 days (95% UCL 3·6%; p=0·031). By 90 days, three (1·8%) outpatients but no inpatients had developed major bleeding (95% UCL 4·5%; p=0·086). Mean length of stay was 0·5 days (SD 1·0) for outpatients and 3·9 days (SD 3·1) for inpatients.
  
  
  CONCLUSIONS
  In selected low-risk patients with pulmonary embolism, outpatient care can safely and effectively be used in place of inpatient care.
  
  
  BACKGROUND
  Swiss National Science Foundation, Programme Hospitalier de Recherche Clinique, and the US National Heart, Lung, and Blood Institute. Sanofi-Aventis provided free drug supply in the participating European centres.
authors.affiliation: Bern University Hospital, Switzerland. drahomir.aujesky@insel.ch
authors.forename: Drahomir
authors.initials: D
authors.lastname: Aujesky
authors.forename: Pierre-Marie
authors.initials: PM
authors.lastname: Roy
authors.forename: Franck
authors.initials: F
authors.lastname: Verschuren
authors.forename: Marc
authors.initials: M
authors.lastname: Righini
authors.forename: Joseph
authors.initials: J
authors.lastname: Osterwalder
authors.forename: Michael
authors.initials: M
authors.lastname: Egloff
authors.forename: Bertrand
authors.initials: B
authors.lastname: Renaud
authors.forename: Peter
authors.initials: P
authors.lastname: Verhamme
authors.forename: Roslyn A
authors.initials: RA
authors.lastname: Stone
authors.forename: Catherine
authors.initials: C
authors.lastname: Legall
authors.forename: Olivier
authors.initials: O
authors.lastname: Sanchez
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Pugh
authors.forename: Alfred
authors.initials: A
authors.lastname: N'gako
authors.forename: Jacques
authors.initials: J
authors.lastname: Cornuz
authors.forename: Olivier
authors.initials: O
authors.lastname: Hugli
authors.forename: Hans-Jürg
authors.initials: HJ
authors.lastname: Beer
authors.forename: Arnaud
authors.initials: A
authors.lastname: Perrier
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Fine
authors.forename: Donald M
authors.initials: DM
authors.lastname: Yealy
mesh_terms: D000208:Acute Disease; D000284:Administration, Oral; D000553:Ambulatory Care; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects; D017984:Enoxaparin / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D006295:Health Resources / Q000706:statistics & numerical data; D006470:Hemorrhage / Q000139:chemically induced; D006760:Hospitalization; D006801:Humans; D007279:Injections, Subcutaneous; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010359:Patient Readmission; D017060:Patient Satisfaction; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000188:drug therapy*; D012008:Recurrence
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin