title: Colloid osmotic pressure and extravasation of plasma proteins following infusion of Ringer's acetate and hydroxyethyl starch 130/0.4.
abstract: BACKGROUND
  During fluid infusion therapy, plasma proteins are diluted and leak from the intravascular space, which alters the colloid osmotic pressure (COP) and potentially affects coagulation. We hypothesised that acetated Ringer's and starch solution, alone or in combination, influence these mechanisms differently.
  
  
  METHODS
  On different occasions, 10 male volunteers were infused with 20 ml/kg acetated Ringer's and 10 ml/kg 6% hyroxyethyl starch 130/0.4 (Voluven(®) ) alone or in combination (first with starch solution followed by Ringer's solution). Blood samples were collected every 30-min for measurements of COP, blood haemoglobin, platelets, and plasma concentrations of albumin, immunoglobulins (IgG and IgM), coagulation factor VII (FVII), fibrinogen, cystatin C, activated partial thromboplastin time (APTT) and prothrombin international normalised ratio (PT-INR). Changes were compared with the haemoglobin-derived plasma dilution.
  
  
  RESULTS
  The COP increased by 8.4% (SD 3) with starch and decreased by 26.2% (7.9) with Ringer's. These infusions diluted the plasma by 23.4% (5.3) and 18.7% (4.9) respectively. The COP changes in the combined experiment followed the same pattern as the individual infusions. Albumin and IgG changes in excess of the plasma dilution were very subtle. The intravascular contents of the IgM and platelets decreased, whereas FVII, fibrinogen and cystatin C increased. PT-INR increased by 1/3 of the plasma dilution, whereas changes in APTT did not correlate with the plasma dilution.
  
  
  CONCLUSIONS
  The starch increased COP and only minor capillary leak occurred in healthy volunteers. The fluid-induced plasma dilution correlated with mild impairment of the extrinsic coagulation pathway but not of the intrinsic pathway.
authors.affiliation: Department of Anaesthesiology, Vrinnevi Hospital, Norrköping, Sweden.|Section for Anaesthesia, Linköping University, Linköping, Sweden.
authors.forename: J H
authors.initials: JH
authors.lastname: Zdolsek
authors.affiliation: Section for Anaesthesia, Linköping University, Linköping, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Bergek
authors.affiliation: Department of Clinical Chemistry, Linköping University, Linköping, Sweden.
authors.forename: T L
authors.initials: TL
authors.lastname: Lindahl
authors.affiliation: Section for Anaesthesia, Linköping University, Linköping, Sweden.|Research Department, Södertälje Hospital, Södertälje, Sweden.
authors.forename: R G
authors.initials: RG
authors.lastname: Hahn
mesh_terms: D000293:Adolescent; D000328:Adult; D001798:Blood Proteins / Q000378:metabolism*; D002199:Capillary Permeability; D003102:Colloids; D005440:Fluid Therapy; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D007552:Isotonic Solutions / Q000494:pharmacology*; D008297:Male; D009997:Osmotic Pressure; D010314:Partial Thromboplastin Time; D055815:Young Adult
chemical_list: D001798:Blood Proteins; D003102:Colloids; C485123:HES 130-0.4; D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; C028570:Ringer's acetate