title: Outpatient treatment of acute poisoning by substances of abuse: a prospective observational cohort study.
abstract: BACKGROUND
  Procedures for the clinical assessment of acute poisoning by substances of abuse should identify patients in need of hospital admission and avoid hazardous discharges, while keeping the observation time short. We assess the safety of a systematic procedure developed at the Oslo Accident and Emergency Outpatient Clinic (OAEOC).
  
  
  METHODS
  All patients 12 years and older treated for acute poisoning by substances of abuse at the OAEOC were included consecutively from October 2011 to September 2012. Data were collected on pre-set registration forms. Information on re-presentations to health services nation-wide during the first week following discharge was retrieved from the Norwegian Patient Register and from local electronic medical records. Information on fatalities was obtained from the Norwegian Cause of Death Registry.
  
  
  RESULTS
  There were 2343 cases of acute poisoning by substances of abuse. The main toxic agent was ethanol in 1291 (55 %) cases, opioids in 539 (23 %), benzodiazepines in 194 (8 %), central stimulants in 132 (6 %), and gamma-hydroxybutyrate (GHB) in 105 (4 %). Median observation time was four hours. The patient was hospitalised in 391 (17 %) cases. Two patients died during the first week following discharge, both from a new opioid poisoning. Among 1952 discharges, 375 (19 %) patients re-presented at the OAEOC or a hospital within a week; 13 (0.7 %) with a diagnosis missed at the index episode, 169 (9 %) with a new poisoning, 31 (2 %) for follow-up of concomitant conditions diagnosed at index, and 162 (8 %) for unrelated events. Among the patients with missed diagnoses, five needed further treatment for the same poisoning episode, two were admitted with psychosis, one had hemorrhagic gastritis, another had fractures in need of surgery and four had minor injuries.
  
  
  CONCLUSIONS
  The procedure in use at the OAEOC can be considered safe and could be implemented elsewhere. The high re-presentation rate calls for better follow-up.
authors.affiliation: Department of General Practice, University of Oslo, Oslo, Norway. o.m.vallersnes@medisin.uio.no.|Department of Emergency General Practice, Oslo Accident and Emergency Outpatient Clinic, City of Oslo Health Agency, Oslo, Norway. o.m.vallersnes@medisin.uio.no.
authors.forename: Odd Martin
authors.initials: OM
authors.lastname: Vallersnes
authors.affiliation: Department of Acute Medicine, Oslo University Hospital, Oslo, Norway.
authors.forename: Dag
authors.initials: D
authors.lastname: Jacobsen
authors.affiliation: Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway.|Department of Behavioural Sciences in Medicine, University of Oslo, Oslo, Norway.
authors.forename: Øivind
authors.initials: Ø
authors.lastname: Ekeberg
authors.affiliation: Department of General Practice, University of Oslo, Oslo, Norway.
authors.forename: Mette
authors.initials: M
authors.lastname: Brekke
mesh_terms: D000208:Acute Disease; D000328:Adult; D000554:Ambulatory Care Facilities; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D010045:Outpatients; D011041:Poisoning / Q000453:epidemiology / Q000209:etiology / Q000628:therapy*; D011446:Prospective Studies; D019966:Substance-Related Disorders / Q000150:complications* / Q000453:epidemiology; D015996:Survival Rate / Q000639:trends; D013997:Time Factors
keywords: Alcohol; Benzodiazepines; Central stimulants; GHB; Opioids; Triage