title: The effects of hypohydration on central venous pressure and splenic volume in adult horses.
abstract: BACKGROUND
  Central venous pressure (CVP) is used in many species to monitor right-sided intravascular volume status, especially in critical care medicine.
  
  
  OBJECTIVE
  That hypohydration in adult horses is associated with a proportional reduction in CVP.
  
  
  METHODS
  Ten healthy adult horses from the university teaching herd.
  
  
  METHODS
  In this experimental study, horses underwent central venous catheter placement and CVP readings were obtained by water manometry. The horses were then deprived of water and administered furosemide (1 mg/kg IV q6h) for up to 36 hours. Weight, CVP, vital signs, PCV, total protein (TP), and serum lactate were monitored at baseline and every 6 hours until a target of 5% decrease in body weight loss was achieved. The spleen volume was estimated sonographically at baseline and peak volume depletion. Linear regression analysis was used to assess the association of CVP and other clinical parameters with degree of body weight loss over time.
  
  
  RESULTS
  There was a significant association between CVP and decline in body weight (P < .001), with a decrease in CVP of 2.2 cmH(2)O for every percentage point decrease in body weight. Other significant associations between volume depletion and parameters measured included increased TP (P = .007), increased serum lactate concentration (P = .048), and decreased splenic volume (P = .046). There was no significant association between CVP and vital signs or PCV.
  
  
  CONCLUSIONS
  These findings suggest that CVP monitoring might be a useful addition to the clinical evaluation of hydration status in adult horses.
authors.affiliation: Department of Clinical Studies, New Bolton Center, University of Pennsylvania, Kennett Square, PA 19348, USA. rnolenw@vet.upenn.edu
authors.forename: R D
authors.initials: RD
authors.lastname: Nolen-Walston
authors.forename: J L
authors.initials: JL
authors.lastname: Norton
authors.forename: C
authors.initials: C
authors.lastname: Navas de Solis
authors.forename: C
authors.initials: C
authors.lastname: Underwood
authors.forename: R
authors.initials: R
authors.lastname: Boston
authors.forename: J
authors.initials: J
authors.lastname: Slack
authors.forename: B L
authors.initials: BL
authors.lastname: Dallap
mesh_terms: D000818:Animals; D001810:Blood Volume; D002496:Central Venous Pressure / Q000187:drug effects; D003681:Dehydration / Q000473:pathology / Q000503:physiopathology / Q000662:veterinary*; D004232:Diuretics / Q000633:toxicity; D005665:Furosemide / Q000633:toxicity; D006734:Horse Diseases / Q000139:chemically induced / Q000473:pathology* / Q000503:physiopathology*; D006736:Horses; D013154:Spleen / Q000000981:diagnostic imaging / Q000473:pathology*; D014463:Ultrasonography; D014868:Water Deprivation
chemical_list: D004232:Diuretics; D005665:Furosemide