title: Application of multifrequency bioelectrical impedance analysis method for the detection of dehydration status in professional divers.
abstract: OBJECTIVE
  The level of dehydration has been known to be a predisposing factor for the development of decompression sickness in divers. The aim of this study was to determine the level of dehydration in divers who dove with heliox and to determine whether the source of this dehydration was intracellular and/or extracellular by means of multifrequency bioelectrical impedance analysis (MF-BIA).
  
  
  METHODS
  Eleven male professional divers were enrolled in the study. In order to determine the level of dehydration, MF-BIA was carried out (at 5, 50, and 100 kHz) and capillary hematocrit (Hct) was measured two times: one before diving and the other after leaving the pressure room.
  
  
  RESULTS
  When prediving and postdiving parameters were compared, significant increases in the resistance at 5 kHz (P<0.001), 50 kHz, (P<0.001), and 100 kHz (P<0.01) and Hct (P<0.01) were observed after the diving. Similarly, a statistically significant fluid shift was found: total body water, -1.30 L (P<0.001), extracellular water, -0.85 L (P<0.001); and intracellular water, -0.45 L (P=0.011).
  
  
  CONCLUSIONS
  Our results showed that mild dehydration occurred both in the intracellular and extracellular compartments in divers after deep diving. This study also indicates that MF-BIA could be a reliable new method for determining the dehydration status in divers.
authors: Department of Underwater and Hyperbaric Medicine, Istanbul Faculty of Medicine, Istanbul University, Turkey.
authors: Sermin
authors: S
authors: Sengun
authors: Atilla
authors: A
authors: Uslu
authors: Salih
authors: S
authors: Aydin
mesh_terms: D000328:Adult; D003665:Decompression Sickness / Q000175:diagnosis*; D003681:Dehydration / Q000175:diagnosis*; D004242:Diving / Q000009:adverse effects*; D017097:Electric Impedance; D006801:Humans; D008297:Male