title: Pulmonary extravascular fluid accumulation in recreational climbers: a prospective study.
abstract: BACKGROUND
  High altitude pulmonary oedema (HAPE) that is severe enough to require urgent medical care is infrequent. We hypothesised that subclinical HAPE is far more frequent than suspected during even modest climbs of average effort.
  
  
  METHODS
  We assessed 262 consecutive climbers of Monte Rosa (4559 m), before ascent and about 24 h later on the summit 1 h after arriving, by clinical examination, electrocardiography, oximetry, spirometry, carbon monoxide transfer, and closing volume. A chest radiograph was taken at altitude.
  
  
  RESULTS
  Only one climber was evacuated for HAPE, but 40 (15%) of 262 climbers had chest rales or interstitial oedema on radiograph after ascent. Of 37 of these climbers, 34 (92%) showed increased closing volume. Of the 197 climbers without oedema, 146 (74%) had an increase in closing volume at altitude. With no change in vital capacity, forced expiratory volume in 1 s and forced expiratory flow at 25-75% of forced vital capacity increased slightly at altitude, without evidence of oedema. If we assume that an increased closing volume at altitude indicates increased pulmonary extravascular fluid, our data suggest that three of every four healthy, recreational climbers have mild subclinical HAPE shortly after a modest climb.
  
  
  CONCLUSIONS
  The risk of HAPE might not be confined to a small group of genetically susceptible people, but likely exists for most climbers if the rate of ascent and degree of physical effort are great enough, especially if lung size is normal or low.
authors.affiliation: Unit of Respiratory Medicine, San Raffaele University Scientific Institute, Via Olgettina 60, 20132 Milano, Italy. george.cremona@hsr.it
authors.forename: George
authors.initials: G
authors.lastname: Cremona
authors.forename: Roberto
authors.initials: R
authors.lastname: Asnaghi
authors.forename: Paolo
authors.initials: P
authors.lastname: Baderna
authors.forename: Alessandro
authors.initials: A
authors.lastname: Brunetto
authors.forename: Tom
authors.initials: T
authors.lastname: Brutsaert
authors.forename: Carmelo
authors.initials: C
authors.lastname: Cavallaro
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Clark
authors.forename: Annalisa
authors.initials: A
authors.lastname: Cogo
authors.forename: Roberto
authors.initials: R
authors.lastname: Donis
authors.forename: Paola
authors.initials: P
authors.lastname: Lanfranchi
authors.forename: Andrew
authors.initials: A
authors.lastname: Luks
authors.forename: Nadia
authors.initials: N
authors.lastname: Novello
authors.forename: Stefano
authors.initials: S
authors.lastname: Panzetta
authors.forename: Liliana
authors.initials: L
authors.lastname: Perini
authors.forename: Marci
authors.initials: M
authors.lastname: Putnam
authors.forename: Liliana
authors.initials: L
authors.lastname: Spagnolatti
authors.forename: Harrieth
authors.initials: H
authors.lastname: Wagner
authors.forename: Peter D
authors.initials: PD
authors.lastname: Wagner
mesh_terms: D000328:Adult; D000532:Altitude Sickness / Q000175:diagnosis* / Q000503:physiopathology; D015633:Extravascular Lung Water / Q000378:metabolism*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D009051:Mountaineering / Q000502:physiology; D011654:Pulmonary Edema / Q000175:diagnosis* / Q000503:physiopathology; D011998:Recreation; D012129:Respiratory Function Tests; D014797:Vital Capacity / Q000502:physiology