title: B-type natriuretic peptide after open-water and hyperbaric chamber exposure to 10 msw.
abstract: BACKGROUND
  Hyperbaric environment exposure in humans has cardiovascular effects mainly characterized by an increase in afterload and a decrease in cardiac output. In a previous study we did not find B-type natriuretic peptide (BNP) changes in healthy volunteers exposed to hyperbaric oxygen while other authors documented a significant increase in N-terminal pro-BNP after scuba diving. On the basis of these data we hypothesized that dry hyperbaric exposure and scuba diving could have different effects on BNP secretion.
  
  
  METHODS
  Nine healthy volunteers performed a 1-h open-sea air dive at 10 m depth (T); a few days later they were compressed in air in a hyperbaric chamber (CT) using the same dive profile. Three venous blood samples were drawn for each session: before starting the dives (T0 and CT0), immediately after exiting the water and the chamber (T1 and CT1), and 5 h later (T2 and CT2).
  
  
  RESULTS
  A significant increase in plasma BNP was found with respect to baseline conditions after scuba diving both at T1 (median increment +32.69% [interquartile range +25.62 to +65.35%]) and at T2 (+28.03% [+23.08 to +38.92%]) while no differences were documented after the same dive in dry conditions either at CT1 (+1.34% [-17.57 to +33.55%]) or at CT2 (0.00% [17,67 to +21.62%]).
  
  
  CONCLUSIONS
  These preliminary findings show that scuba diving and dry hyperbaric exposure, although at the same environmental pressure, cause different effects on ventricular loads in healthy subjects.
authors: Department of Anesthesia and Intensive Care, Azienda Ospedaliero-Universitaria, University of Trieste School of Medicine, Trieste, Italy. paolo.grassi@aots.sanita.fvg.it
authors: Paolo
authors: P
authors: Grassi
authors: Elisabetta
authors: E
authors: Stenner
authors: Adriano
authors: A
authors: Rinaldi
authors: Giorgio
authors: G
authors: Delbello
authors: Clara
authors: C
authors: Piccinini
authors: Andrea
authors: A
authors: Bussani
authors: Bruno
authors: B
authors: Biancardi
authors: Bruno
authors: B
authors: Biasioli
authors: Giorgio
authors: G
authors: Berlot
mesh_terms: D000328:Adult; D004242:Diving / Q000502:physiology*; D006801:Humans; D006931:Hyperbaric Oxygenation; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*
chemical_list: D020097:Natriuretic Peptide, Brain