title: Validation of a brief observation period for patients with cocaine-associated chest pain.
abstract: BACKGROUND
  Retrospective studies of patients with cocaine-associated chest pain suggest that a strategy of discharging patients from the emergency department after a 12-hour observation period if they do not have evidence of ischemia should be associated with a very low rate of complications.
  
  
  METHODS
  We prospectively evaluated the safety of a 9-to-12-hour observation period in patients with cocaine-associated chest pain who were at low-to-intermediate risk of cardiovascular events. Consecutive patients who reported or tested positive for cocaine use and who received protocol-driven care in a chest-pain observation unit were included. Patients who had normal levels of troponin I, without new ischemic changes on electrocardiography, and who had no cardiovascular complications (dysrhythmias, acute myocardial infarction, or recurrent symptoms) during the 9-to-12-hour observation period were discharged from the unit. The main outcome was death from cardiovascular causes at 30 days.
  
  
  RESULTS
  Three hundred forty-four patients with cocaine-associated chest pain were evaluated. Forty-two of these patients (12 percent) were directly admitted to the hospital. The study cohort comprised the remaining 302 patients. During the 30-day follow-up period, none of the patients died of a cardiovascular event (0 percent; 95 percent confidence interval, 0 to 0.99), and only 4 of the 256 patients for whom detailed follow-up data were available had a nonfatal myocardial infarction (1.6 percent; 95 percent confidence interval, 0.1 to 3.1). All four nonfatal myocardial infarctions occurred in patients who continued to use cocaine.
  
  
  CONCLUSIONS
  Patients with cocaine-associated chest pain who do not have evidence of ischemia or cardiovascular complications over a 9-to-12-hour period in a chest-pain observation unit have a very low risk of death or myocardial infarction during the 30 days after discharge.
authors.affiliation: Departments of Emergency Medicine, University of Michigan, Ann Arbor, and Hurley Medical Center, Flint, Mich, USA.
authors.forename: Jim Edward
authors.initials: JE
authors.lastname: Weber
authors.forename: Frances S
authors.initials: FS
authors.lastname: Shofer
authors.forename: G Luke
authors.initials: GL
authors.lastname: Larkin
authors.forename: Amit S
authors.initials: AS
authors.lastname: Kalaria
authors.forename: Judd E
authors.initials: JE
authors.lastname: Hollander
mesh_terms: D000328:Adult; D002637:Chest Pain / Q000139:chemically induced*; D003042:Cocaine / Q000009:adverse effects*; D019970:Cocaine-Related Disorders / Q000150:complications* / Q000401:mortality; D003937:Diagnosis, Differential; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000139:chemically induced* / Q000175:diagnosis / Q000453:epidemiology; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D003042:Cocaine