title: Predictors of ear barotrauma in aircrews exposed to simulated high altitude.
abstract: BACKGROUND
  Ear barotrauma is an adverse effect related to hypobaric exposure. Ear, nose, and throat (ENT) diseases are risk factors for barotrauma in aircrews trained in a hypobaric chamber, but excluding affected subjects from exposure does not abolish the risk in asymptomatic trainees. We investigated other possible predictors, including history of ENT diseases, ENT clinical abnormalities, altitude, and subject's age.
  
  
  METHODS
  After a complete ENT evaluation including otoscopy and tympanometry, 314 aircrews underwent hypobaric chamber training. Two altitude training profiles up to 35,000 ft (10,668 m) and 25,000 ft (7620 m), respectively, were used. Subjects were grouped according to if they were asymptomatic, had acute barotitis, or reported delayed ear pain the day after the exposure.
  
  
  RESULTS
  There were 7 men who had acute barotitis (incidence of 2.3%) and 28 men who had delayed ear pain (incidence of 9.2%). A significant association resulted between history of ENT diseases and delayed ear pain and between abnormal ENT findings and acute barotitis in subjects exposed to the higher profile. Altitude was associated with increased risk of delayed ear pain. Delayed ear pain was associated with older age in subjects exposed to the lower altitude and younger age in subjects exposed to the higher altitude.
  
  
  CONCLUSIONS
  Our data suggest that in subjects exposed to 35,000 ft (10,668 m), the history of previous ENT diseases and younger age may be valid predictors of delayed ear pain, while abnormal ENT findings may predict acute barotitis. At 25,000 ft (7620 m), subjects with older age may have increased risk of delayed ear pain.
authors: Italian Air Force Logistic Command, Flight Test Centre, Aerospace Medicine Department, Pratica di Mare, Rome, Italy. fabio.morgagni@aeronautica.difesa.it
authors: Fabio
authors: F
authors: Morgagni
authors: Alberto
authors: A
authors: Autore
authors: Angelo
authors: A
authors: Landolfi
authors: Mario
authors: M
authors: Ciniglio Appiani
authors: Giuseppe
authors: G
authors: Ciniglio Appiani
mesh_terms: D000158:Acoustic Impedance Tests; D000328:Adult; D000337:Aerospace Medicine; D000531:Altitude; D001469:Barotrauma / Q000209:etiology / Q000517:prevention & control*; D004433:Earache / Q000209:etiology / Q000517:prevention & control; D004780:Environment, Controlled; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D008403:Mass Screening; D008889:Military Personnel; D010033:Otitis Media / Q000209:etiology / Q000517:prevention & control*; D038781:Otoscopy; D018570:Risk Assessment