title: Comparison of Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD) relating to cardiac arrest calls.
abstract: BACKGROUND
  Prompt emergency medical service (EMS) system activation with rapid delivery of pre-hospital treatment is essential for patients suffering out-of-hospital cardiac arrest (OHCA). The two most commonly used dispatch tools are Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD). We compared cardiac arrest call processing using these two dispatch tools in two different dispatch centres.
  
  
  METHODS
  Observational study of adult EMS confirmed (non-EMS witnessed) OHCA calls during one year in Richmond, USA (MPD) and Oslo, Norway (CBD). Patients receiving CPR prior to call, interrupted calls or calls where the caller did not have access to the patients were excluded from analysis. Dispatch logs, ambulance records and digitalized dispatcher and caller voice recordings were compared.
  
  
  RESULTS
  The MPDS-site processed 182 cardiac arrest calls and the CBD-site 232, of which 100 and 140 calls met the inclusion criteria, respectively. The recognition of cardiac arrest was not different in the MPD and CBD systems; 82% vs. 77% (p=0.42), and pre-EMS arrival CPR instructions were offered to 81% vs. 74% (p=0.22) of callers, respectively. Time to ambulance dispatch was median (95% confidence interval) 15 (13, 17) vs. 33 (29, 36) seconds (p<0.001) and time to chest compression delivery; 4.3 (3.7, 4.9) vs. 3.7 (3.0, 4.1)min for the MPD and CBD systems, respectively (p=0.05).
  
  
  CONCLUSIONS
  Pre-arrival CPR instructions were offered faster and more frequently in the CBD system, but in both systems chest compressions were delayed 3-4min. Earlier recognition of cardiac arrest and improved CPR instructions may facilitate earlier lay rescuer CPR.
authors: Institute of Clinical Medicine, University of Oslo, PB 1171, Blindern, N-0318 Oslo, Norway; Institute for Experimental Medical Research, Oslo University Hospital, PB 4956, Nydalen, N-0424 Oslo, Norway. Electronic address: camilla.hardeland@medisin.uio.no.
authors: Camilla
authors: C
authors: Hardeland
authors: Department of Anaesthesiology and Institute for Experimental Medical Research, Oslo University Hospital, PB 4956, Nydalen, N-0424 Oslo, Norway.
authors: Theresa M
authors: TM
authors: Olasveengen
authors: Richmond Ambulance Authority, 2400 Hermitage Rd, Richmond, Virgina 23220, USA.
authors: Rob
authors: R
authors: Lawrence
authors: Richmond Ambulance Authority, 2400 Hermitage Rd, Richmond, Virgina 23220, USA.
authors: Danny
authors: D
authors: Garrison
authors: Municipality of Skedsmo, PB 313, 2000 Lillestrøm, Norway.
authors: Tonje
authors: T
authors: Lorem
authors: Emergency Medical Communication Centre and Air Ambulance Department, Oslo University Hospital, PB 4956, Nydalen, N-0424 Oslo, Norway.
authors: Gunnar
authors: G
authors: Farstad
authors: National Centre for Prehospital Emergency Medicine, Oslo University Hospital, PB 4956, Nydalen, N-0424 Oslo, Norway.
authors: Lars
authors: L
authors: Wik
mesh_terms: D000328:Adult; D016887:Cardiopulmonary Resuscitation; D017598:Efficiency, Organizational; D004631:Emergency Medical Service Communication Systems; D004632:Emergency Medical Services; D005260:Female; D006801:Humans; D008297:Male; D009664:Norway; D058687:Out-of-Hospital Cardiac Arrest / Q000628:therapy*; D014481:United States
keywords: Cardiac arrest; Criteria Based Dispatch; Dispatch; EMS; Medical Priority Dispatch; Resuscitation