title: Lung function after cold-water dives with a standard scuba regulator or full-face-mask during wintertime.
abstract: BACKGROUND
  Full-face-masks (FFM) prevent the diver's face from cold and can support nasal breathing underwater. The aim of the study was to evaluate the effect of the use of FFMs on lung function and wellbeing.
  
  
  METHODS
  Twenty-one, healthy, non-asthmatic divers performed two cold-water dives (4⁰C, 25 min, 10 metres' depth) - one with a FFM and the other with a standard scuba regulator (SSR). Spirometry was performed before and after each dive and well-being and cold sensation were assessed after the dives.
  
  
  RESULTS
  Significant decreases in forced vital capacity (FVC), forced expiratory volume in one second (FEV₁) and midexpiratory flow at 75% of FVC (MEF₇₅) occurred after both FFM and SSR dives. Changes in FVC and FEV₁ did not differ significantly between FFM and SSR dives. However, the mid-expiratory flows measured at 50% and 25% of FVC (MEF₅₀ and MEF₂₅) were significantly lower 10 minutes after the FFM dive compared to 10 minutes after the SSR dive. The wellbeing and cold sensation of the divers were significantly improved with FFM dives compared to SSR dives.
  
  
  CONCLUSIONS
  Cold-water dives during wintertime can be associated with airway narrowing. During cold-water dives, the use of a FFM appears to reduce the cold sensation and enhance the well-being of the divers. However, a FFM does not appear to prevent airway narrowing in healthy, non-asthmatic subjects.
authors.affiliation: Department of Anesthesiology, University of Ulm and Friedrich Schiller University, Jena, Germany, E-mail: florian_uhlig@freenet.de.
authors.forename: Florian
authors.initials: F
authors.lastname: Uhlig
authors.affiliation: Department of Anesthesiology, University of Ulm, Germany.
authors.forename: Claus-Martin
authors.initials: CM
authors.lastname: Muth
authors.affiliation: Department of Sports Medicine, University of Tuebingen, Germany.
authors.forename: Kay
authors.initials: K
authors.lastname: Tetzlaff
authors.affiliation: German Naval Medical Institute, Kiel-Kronshagen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Koch
authors.affiliation: Department of Anesthesiology, University of Regensburg.
authors.forename: Richard
authors.initials: R
authors.lastname: Leberle
authors.affiliation: Department of Anesthesiology, University of Ulm, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Georgieff
authors.affiliation: Department of Anesthesiology, University of Ulm, Germany and Department of Anesthesiology and Intensive Care Medicine, University Hospital, Leipzig, Germany.
authors.forename: Bernd E
authors.initials: BE
authors.lastname: Winkler
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016084:Bronchoconstriction / Q000502:physiology; D003081:Cold Climate / Q000009:adverse effects; D003080:Cold Temperature / Q000009:adverse effects; D004242:Diving / Q000502:physiology*; D004867:Equipment Design; D005145:Face; D005541:Forced Expiratory Volume / Q000502:physiology*; D006801:Humans; D008297:Male; D008397:Masks; D008875:Middle Aged; D012621:Seasons; D013147:Spirometry; D013997:Time Factors; D014797:Vital Capacity / Q000502:physiology*; D014867:Water; D055815:Young Adult
chemical_list: D014867:Water
keywords: Cold; diving reflex; lung function; physiology; scuba diving; thermal problems (hypothermia and hyperthermia)