title: Differences between chest pain observation service patients and admitted "rule-out myocardial infarction" patients.
abstract: OBJECTIVE
  To compare and contrast the patient characteristics of ED patients at low risk for acute cardiac ischemia who were assigned to a chest pain observation service vs those admitted to a monitored inpatient bed for "rule-out acute myocardial infarction" (R/O MI).
  
  
  METHODS
  This was a retrospective, cross-sectional comparison of adult patients considered at relatively low risk for cardiac ischemia and who were evaluated in 1 of 2 settings: a short-term observation service and an inpatient monitored bed. All patients had an ED final diagnosis of "chest pain," "R/O MI," or "unstable angina" during the 7-month study period. Demographic features and presenting clinical features were examined as a function of site of patient evaluation.
  
  
  RESULTS
  Of 531 study patients, 265 (50%) were assigned to the observation service. Younger age (OR = 1.75, 95% CI 1.26, 2.44, for each decrement of 20 years), the complaint of "chest pain" (OR = 2.35, 95% CI 1.34, 4.12), and the absence of prior known coronary artery disease (OR = 1.64, 95% CI 1.13, 2.38) were the principal independent factors associated with assignment to a chest pain observation service bed.
  
  
  CONCLUSIONS
  Patients evaluated in a chest pain observation service appear to have different clinical characteristics than other individuals admitted to a monitored inpatient bed for "R/O MI." Investigators should address differences in clinical characteristics when making outcome comparisons between these 2 patient groups.
authors.affiliation: Division of Emergency Medicine, Duke University Medical Center, Durham, NC 27710, USA. dalljohn@acpub.duke.edu
authors.forename: J
authors.initials: J
authors.lastname: Dallara
authors.forename: H W
authors.initials: HW
authors.lastname: Severance
authors.forename: B
authors.initials: B
authors.lastname: Davis
authors.forename: G
authors.initials: G
authors.lastname: Schulz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D019090:Case Management; D002637:Chest Pain / Q000175:diagnosis / Q000453:epidemiology*; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D003657:Decision Making; D004562:Electrocardiography; D004636:Emergency Service, Hospital / Q000458:organization & administration / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D009203:Myocardial Infarction / Q000175:diagnosis; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000453:epidemiology*; D010343:Patient Admission / Q000706:statistics & numerical data; D018579:Patient Selection; D012189:Retrospective Studies; D018570:Risk Assessment; D014218:Triage / Q000592:standards / Q000706:statistics & numerical data*