title: Quantification and predictors of plasma volume expansion from mannitol treatment.
abstract: OBJECTIVE
  To determine the effects of acute hypertonic mannitol infusion on intravascular volume expansion and to identify potential predictors of hypervolemia.
  
  
  METHODS
  Measurements of plasma volume and volume regulatory hormones were performed in healthy volunteers before and over 90 min after acute infusion of 20% mannitol solution in a therapeutic dose of 0.5 g/kg body weight, equalling an average infusion volume of 180 ml.
  
  
  METHODS
  Clinical research unit in an 800-bed teaching hospital in the eastern part of Switzerland.
  
  
  METHODS
  Eight normal male volunteers.
  
  
  RESULTS
  Baseline plasma volume was determined by the indocyanine green dye dilution technique. Serial plasma protein measurements were performed after mannitol infusion to calculate intravascular volume changes. Mannitol administration resulted in a plasma expansion that persisted for more than 90 min and peaked at 112% of the baseline plasma volume 15 min after infusion. Concomitantly, an increase in systolic blood pressure and a fall in plasma sodium concentration occurred. Pharmacokinetic analyses of mannitol distribution and elimination revealed a close relation between plasma volume expansion and mannitol serum concentrations. While renin activity and aldosterone concentrations were suppressed proportionally to the intravascular volume increase, antidiuretic hormone was increased despite notable volume expansion and hyponatremia. Similarly, a rise in atrial natriuretic peptide was detected.
  
  
  CONCLUSIONS
  Therapeutic doses of hypertonic mannitol cause substantial plasma volume expansion, resulting in increased blood pressure. Plasma volume expansion is related to mannitol serum concentrations and mannitol clearance determines the time required to restore normovolemia. ADH and ANP are potentially aggravating factors of mannitol-induced hyponatremia.
authors.affiliation: Department of Internal Medicine, Kantonsspital, Winterthur, Switzerland. nephambp@usz.unizh.ch
authors.forename: P M
authors.initials: PM
authors.lastname: Ambühl
authors.forename: P E
authors.initials: PE
authors.lastname: Ballmer
authors.forename: S
authors.initials: S
authors.lastname: Krähenbühl
authors.forename: R
authors.initials: R
authors.lastname: Krapf
mesh_terms: D000244:Adenosine Diphosphate / Q000097:blood; D000328:Adult; D019540:Area Under Curve; D009320:Atrial Natriuretic Factor / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D004234:Diuretics, Osmotic / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology*; D006207:Half-Life; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008353:Mannitol / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology*; D008657:Metabolic Clearance Rate; D010953:Plasma Volume / Q000187:drug effects*; D012964:Sodium / Q000097:blood
chemical_list: D004234:Diuretics, Osmotic; D008353:Mannitol; D000244:Adenosine Diphosphate; D009320:Atrial Natriuretic Factor; D012964:Sodium