title: A no-decompression air dive and ultrasound lung comets.
abstract: BACKGROUND
  Increased accumulation of extravascular lung water after repetitive deep trimix dives was recently reported. This effect was evident 40 min post-dive, but in subsequent studies most signs of this lung congestion were not evident 2-3 h post-dive, indicating no major negative effects on respiratory gas exchange following deep dives. Whether this response is unique for trimix dives or also occurs in more frequent air dives is presently unknown.
  
  
  METHODS
  A single no-decompression field dive to 33 m with 20 min bottom time was performed by 12 male divers. Multiple ultrasound lung comets (ULC), bubble grade (BG), and single-breath lung diffusing capacity (DLCO) measurements were made before and up to 120 min after the dive.
  
  
  RESULTS
  Median BG was rather high with maximal values observed at 40 min post-dive [median 4 (4-4)]. Arterialization of bubbles from the venous side was observed only in one diver lasting up to 60 min post-dive. Despite high BG, no DCS symptoms were noted. DLCO and ULC were unchanged after the dive at any time point (DLCO(corr) was 33.6 +/- 1.9 ml x min(-1) mmHg(-1) pre-dive, 32.7 +/- 3.8 ml x min(-1) x mmHg(-1) at 60 min post-dive, and 33.2 +/- 5.3 ml x min(-1) x mmHg(-1) at 120 min post-dive; ULC count was 4.1 +/- 1.9 pre-dive, 4.9 +/- 3.3 at 20 min post-dive, and 3.3 +/- 1.9 at 60 min post-dive.
  
  
  CONCLUSIONS
  These preliminary findings show no evidence of increased accumulation of extravascular lung water in male divers after a single no-decompression air dive at the limits of accepted Norwegian diving tables.
authors.affiliation: Department of Physiology, University of Split School of Medicine, Soltanska 2, 21000 Split, Croatia. zeljko.dujic@mefst.hr
authors.forename: Zeljko
authors.initials: Z
authors.lastname: Dujic
authors.forename: Jasna
authors.initials: J
authors.lastname: Marinovic
authors.forename: Ante
authors.initials: A
authors.lastname: Obad
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ivancev
authors.forename: Toni
authors.initials: T
authors.lastname: Breskovic
authors.forename: Pavle
authors.initials: P
authors.lastname: Jovovic
authors.forename: Marko
authors.initials: M
authors.lastname: Ljubkovic
mesh_terms: D000328:Adult; D003665:Decompression Sickness / Q000097:blood; D004242:Diving / Q000502:physiology*; D004452:Echocardiography; D015633:Extravascular Lung Water / Q000000981:diagnostic imaging* / Q000502:physiology; D006801:Humans; D008297:Male; D011653:Pulmonary Diffusing Capacity / Q000502:physiology