title: Preflight versus en route success and complications of rapid sequence intubation in an air medical service.
abstract: BACKGROUND
  Maintenance of an airway in the air medically transported patient is of paramount importance. The purpose of this study is to compare preflight versus en route rapid sequence intubation (RSI)-assisted intubations and to determine the value of air medical use of RSI.
  
  
  METHODS
  This study is a 31-month retrospective review of all patients intubated and transported by a large city air medical service. Subgroup analysis was based on whether patients were transported from a hospital or a scene and whether they were intubated preflight or en route. Information on age, Glasgow Coma Scale score, type of scene, ground time, and previous attempts at intubation was recorded. Complications included failures, multiple attempts at intubation, arrhythmias, and need for repeated paralytic agents. Comparisons were made using a confidence interval analysis. An alpha of 0.05 was considered significant; Bonferroni correction was used for multiple comparisons.
  
  
  RESULTS
  Three hundred twenty-five patients were intubated and transported by Lifeflight during the study period. Two hundred eighty-eight patients were intubated using RSI (89%). The success rate was 97%. Preflight intubations were performed on 100 hospital calls and 86 scene calls. En route intubations were performed on 40 hospital cases and 62 scene calls. Patients who underwent preflight intubations were significantly younger than those who underwent en route intubations for both the hospital group (34 +/- 11 vs. 44 +/- 24 years, p < 0.05) and the scene group (27 +/- 13 vs. 32 +/- 16 years,p < 0.05). Otherwise, the demographic characteristics of the four groups were similar. Trauma accounted for 60 to 70% of hospital transfers and almost 95 to 100% of scene calls. Compared with preflight intubations, there was a significant decrease in ground time for hospital patients who were intubated en route (26 +/- 10 vs. 34 +/- 11 minutes, p < 0.05) and for scene patients who were intubated en route (11 +/- 8 vs. 18 +/- 9 minutes, p < 0.05). There were no significant differences between the groups for number of failures (9 of 288), arrhythmias (18 of 288), or necessity for repeated paralysis (8 of 288). Multiple intubation attempts were performed in more scene preflight patients (30 of 86, 35%) than scene en route patients (16 of 62, 26%), but this did not reach statistical significance. Even for patients having previous attempts at intubation, the success rate using RSI was 93% (62 of 67).
  
  
  CONCLUSIONS
  Air medical intubations, both preflight and en route, for both scene calls and interhospital transports, can be done with a very high success rate. Rapid sequence intubation may improve the success rate. For scene calls, there was a significant decrease in ground time, and there was a trend toward fewer multiple intubation attempts when the patient was intubated en route instead of preflight.
authors.affiliation: Vanderbilt University Lifeflight, Vanderbilt University, Nashville, Tennessee, USA.
authors.forename: E A
authors.initials: EA
authors.lastname: Slater
authors.forename: S J
authors.initials: SJ
authors.lastname: Weiss
authors.forename: A A
authors.initials: AA
authors.lastname: Ernst
authors.forename: M
authors.initials: M
authors.lastname: Haynes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D017732:Air Ambulances; D002648:Child; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014187:Transportation of Patients; D016896:Treatment Outcome