title: Impact of helicopter transport and hospital level on mortality of polytrauma patients.
abstract: BACKGROUND
  Despite numerous studies analyzing this topic, specific advantages of helicopter transport of blunt polytrauma patients as compared with ground ambulances have not yet been identified unequivocally.
  
  
  METHODS
  Four possible pathways in 403 polytrauma patients (Injury Severity Score [ISS] > 16) who were in reach of the helicopter emergency medical service (HEMS) Dresden were analyzed as follows: HEMS-UNI group (n = 140), transfer by HEMS into a university hospital; AMB-REG group (n = 102), transfer by ground ambulance into a regional (Level II or III) hospital; AMB-UNI group (n = 70), transfer by ground ambulance into the university hospital; and INTER group (n = 91), transfer by ground ambulance into a regional hospital, followed by transfer to the university hospital. Scores used were the ISS and the TRISS. Tests used for statistical analysis included chi2 and Fisher's tests. Statistical significance was set at p > 0.05.
  
  
  RESULTS
  Age, gender, and mean ISS (range, 33.3-35.6) revealed extensive homogeneity of the groups. Mortality of the AMB-REG group was almost doubled (41.2%) compared with HEMS-UNI (22.1%) patients (p = 0.002). The AMB-UNI group displayed the lowest mortality (15.7%, p = not significant). TRISS analysis (PRE-Chart) revealed identical outcome for AMB-UNI and HEMS-UNI patients. Rescue time averaged 90 +/- 29 minutes for HEMS-UNI patients, 68 +/- 25 minutes for AMB-UNI patients, and 69 +/- 26 minutes for the AMB-REG group.
  
  
  CONCLUSIONS
  Primary transfer by HEMS into a Level I trauma center reduces mortality markedly. In principle, this benefit can be attributed to superior preclinical therapy, primary admission to a Level I trauma center, or both. However, the identical probability of survival of the AMB-UNI and HEMS-UNI groups in this and comparable studies does not confirm generally better survival rates on account of a more aggressive on-site approach.
authors.affiliation: Department of Trauma and Recontructive Surgery, University Hospital Dresden, Germany. uwc@rcs.urz.tu-dresden.de
authors.forename: Achim
authors.initials: A
authors.lastname: Biewener
authors.forename: Ulf
authors.initials: U
authors.lastname: Aschenbrenner
authors.forename: Stefan
authors.initials: S
authors.lastname: Rammelt
authors.forename: René
authors.initials: R
authors.lastname: Grass
authors.forename: Hans
authors.initials: H
authors.lastname: Zwipp
mesh_terms: D000328:Adult; D017732:Air Ambulances; D000552:Ambulances; D006785:Hospitals, University; D006801:Humans; D015601:Injury Severity Score; D009104:Multiple Trauma / Q000145:classification / Q000401:mortality*; D014187:Transportation of Patients; D014193:Trauma Centers / Q000706:statistics & numerical data*