title: Intra-operative colloid administration increases the clearance of a post-operative fluid load.
abstract: BACKGROUND
  It is unknown whether an intra-operative colloid infusion alters the dynamics of a crystalloid load administered post-operatively.
  
  
  METHODS
  Ten patients received 12.5 ml/kg of Ringer's lactate over 30 min 1-3 days before and 4 h after laparoscopic cholecystectomy, during which 10 ml/kg of a colloid solution, hydroxyethylstarch (HES 130/0.4), was infused. The total body clearance of the pre- and post-operative test infusions was taken as the ratio between the urinary excretion and the Hb-derived dilution of venous plasma over 150 min. The plasma clearance of the infused fluid was calculated using volume kinetics based on the plasma dilution alone. The pre-operative plasma clearance was compared with the post-operative plasma clearance and patients served as their own control.
  
  
  RESULTS
  The urinary excretion averaged 350 ml for the pre-operative infusion and 612 ml post-operatively, which corresponds to 46% and 68% of the pre- and post-operative infusions, respectively. The total body clearance of the crystalloid fluid was 30 ml/min before surgery and 124 ml/min after surgery (P<0.01). The plasma clearance, as obtained from the plasma dilution alone, was 28 and 412 ml/min, respectively. The maximal increase in plasma volume was 410 ml pre-operatively vs. 220 ml post-operatively.
  
  
  CONCLUSIONS
  Infusion of a colloid solution in combination with a crystalloid during laparoscopic cholecystectomy increased the plasma clearance of a post-operative crystalloid infusion.
authors.affiliation: Department of Surgical Gastroenterology, Hvidovre University Hospital, Hvidovre, Denmark. tineborup@yahoo.dk
authors.forename: T
authors.initials: T
authors.lastname: Borup
authors.forename: R G
authors.initials: RG
authors.lastname: Hahn
authors.forename: K
authors.initials: K
authors.lastname: Holte
authors.forename: L
authors.initials: L
authors.lastname: Ravn
authors.forename: H
authors.initials: H
authors.lastname: Kehlet
mesh_terms: D000328:Adult; D000368:Aged; D002763:Cholecystectomy; D003102:Colloids; D005260:Female; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage* / Q000097:blood / Q000494:pharmacology*; D007262:Infusions, Intravenous; D007430:Intraoperative Care; D007700:Kinetics; D019344:Lactic Acid / Q000008:administration & dosage* / Q000097:blood / Q000494:pharmacology*; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period
chemical_list: D003102:Colloids; D006895:Hydroxyethyl Starch Derivatives; D019344:Lactic Acid