title: The Wellington Life Flight Helicopter Emergency Medical Service (HEMS): a retrospective audit against new Ministry of Health criteria.
abstract: OBJECTIVE
  To analyse the clinical and operational indications for activating the Wellington Life Flight helicopter emergency medical service (HEMS) against draft Ministry of Health (MOH) criteria.
  
  
  METHODS
  Wellington HEMS records for 3 years were reviewed. Details of mission location, timings, medical procedures, patient demographics, and primary reasons for dispatch were analysed.
  
  
  RESULTS
  471 missions were reviewed. The main reasons for helicopter dispatch were anticipated time savings (47%), geographical access (36%), provision of skills (7%), or a combination (10%). In 62% of total missions, a road ambulance and helicopter were both dispatched. The helicopter was dispatched after the road ambulance had arrived at the scene in 52% of these cases, with a median lag time of 11 minutes and 12 seconds, and median waiting on scene time of 27 minutes 28 seconds. The road ambulance arrived first in 77% of cases. The median arrival time by air was 26 minutes compared to 11 minutes 45 seconds by road. In contrast, the transfer to hospital by helicopter was quicker in 99% of cases, with a median flight time of 15 minutes compared to 49 minutes by road.
  
  
  CONCLUSIONS
  Wellington HEMS offers advantage over the road ambulance when dispatched and utilised appropriately. The majority of missions satisfied the MOH activation criteria but time-saving issues became apparent. Changes to the Helicopter Dispatch Flowchart have been proposed as a result. Further studies are required to assess any improvement in HEMS response times as the service develops. This data provides a benchmark for audits of future operational and clinical performance.
authors.forename: Katherine
authors.initials: K
authors.lastname: Gordon
authors.affiliation: Department of Surgery and Anaesthesia, University of Otago, PO Box 7343, Wellington 6242, New Zealand. andrew.swain@otago.ac.nz.
authors.forename: Andrew
authors.initials: A
authors.lastname: Swain
authors.forename: Callum
authors.initials: C
authors.lastname: Thirkell
authors.forename: Mark
authors.initials: M
authors.lastname: Bailey
authors.forename: Dave
authors.initials: D
authors.lastname: Greenberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017732:Air Ambulances / Q000592:standards* / Q000706:statistics & numerical data; D002648:Child; D002675:Child, Preschool; D005260:Female; D019983:Guideline Adherence / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008485:Medical Audit; D008875:Middle Aged; D009520:New Zealand; D017410:Practice Guidelines as Topic; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult