title: Helicopter use in rural trauma.
abstract: OBJECTIVE
  To profile a helicopter emergency medical service in rural Australia. To assess patient injury severities and outcomes. To compare missions involving ambulance officers with physicians. To determine any time advantage of the aircraft over ground transfer.
  
  
  METHODS
  Intention-to-treat analysis using retrospective case note review of all helicopter emergency medical service trauma patients from January 2004 to November 2006. Global positioning system mapping technology was used to compare one-way road transfer times with two-way helicopter retrieval.
  
  
  RESULTS
  Two hundred and twenty-two missions were identified from the helicopter log. Forty missions were aborted in flight. Of 182 patients transported, 11 records were incomplete, leaving 171 for analysis. Fifty (29%) patients transported had an Injury Severity Score (ISS) > 15; the average ISS was 12.30 (standard error of the mean 0.82). The average calculated distance flown was 160.4 nautical miles (standard error of the mean 5.29; range 28-360 nautical miles). There was no significant difference in ISS between ambulance officers and physician groups (t = -1.17, P = 0.25, 95% CI -7.37-1.91). There was no difference in the incidence of severe injury (ISS > 15, P = 0.39) or mortality (P = 0.33) when the groups were compared. Air transport was significantly faster beyond 100 km, with a mean difference of 48 min (P = 0.00).
  
  
  CONCLUSIONS
  We could not identify a significant survival benefit attributable to the addition of a doctor, although numbers for this comparison were small. Predicting missions where flight physicians might provide benefit remain imprecise and should be a priority area for prospective evaluation. We have demonstrated that in the absence of special circumstances, a helicopter response within 100 km from base does not improve time to definitive care.
authors.affiliation: Department of Critical Care, Tamworth Rural Referral Hospital, Tamworth, New South Wales, Australia. mattthew.v.shepherd@hnehealth.nsw.gov.au
authors.forename: Matthew Vincent
authors.initials: MV
authors.lastname: Shepherd
authors.forename: Christopher Ernest
authors.initials: CE
authors.lastname: Trethewy
authors.forename: John
authors.initials: J
authors.lastname: Kennedy
authors.forename: Lin
authors.initials: L
authors.lastname: Davis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017732:Air Ambulances / Q000706:statistics & numerical data*; D000552:Ambulances / Q000706:statistics & numerical data; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D009517:New South Wales; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D019035:Rural Health Services / Q000458:organization & administration / Q000706:statistics & numerical data*; D016019:Survival Analysis; D013997:Time Factors; D000078329:Workforce; D014947:Wounds and Injuries / Q000401:mortality / Q000628:therapy*; D055815:Young Adult