title: Hydroxyethyl starch is superior to lactated Ringer as a replacement fluid in a pig model of acute normovolaemic haemodilution.
abstract: BACKGROUND
  Tissue tolerance to oxygen privation during acute normovolaemic haemodilution with different fluids remains unclear. We tested the hypothesis that hydroxyethyl starch (HES) is superior to lactated Ringer's solution in pigs for preserving tissue perfusion during acute normovolaemic haemodilution.
  
  
  METHODS
  Twenty-four animals were randomized into control, lactated Ringer's solution and HES groups. All groups, except the control, underwent acute normovolaemic haemodilution. Haemodynamics, oxygen parameter indices, global anaerobic metabolic markers, echocardiographic parameters, gastric tonometry and serum osmolarity were monitored at baseline, immediately after (0 min) and 60 and 120 min after the end of haemodilution. Myocardial, liver, stomach and intestine samples were collected for further evaluation.
  
  
  RESULTS
  Cardiac and oxygen parameter index responses to acute normovolaemic haemodilution were comparable. However, the increment in cardiac index, stroke volume index, and left ventricular stroke work index were more sustained in the starch group. In the lactated Ringer's group, gastric pH decreased significantly and was accompanied by a significant increase in lactate. Myocardial ultrastructure was better preserved in the starch group. The other tissue samples presented no change.
  
  
  CONCLUSIONS
  In this model of ANH, the starch group had a superior haemodynamic response. Minor loss of myocardial cellular integrity and preserved gastric pHi reinforce these findings.
authors.affiliation: Laboratory of Medical Investigation LIM08, School of Medicine Brazil.
authors.forename: D A
authors.initials: DA
authors.lastname: Otsuki
authors.forename: D T
authors.initials: DT
authors.lastname: Fantoni
authors.forename: C B
authors.initials: CB
authors.lastname: Margarido
authors.forename: C K
authors.initials: CK
authors.lastname: Marumo
authors.forename: T
authors.initials: T
authors.lastname: Intelizano
authors.forename: C A
authors.initials: CA
authors.lastname: Pasqualucci
authors.forename: J O
authors.initials: JO
authors.lastname: Costa Auler
mesh_terms: D000818:Animals; D001794:Blood Pressure; D002302:Cardiac Output; D004195:Disease Models, Animal; D006339:Heart Rate; D006352:Heart Ventricles / Q000648:ultrastructure; D006400:Hematocrit; D006438:Hemodilution / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D006895:Hydroxyethyl Starch Derivatives / Q000627:therapeutic use*; D007552:Isotonic Solutions / Q000627:therapeutic use*; D008854:Microscopy, Electron; D009210:Myofibrils / Q000648:ultrastructure; D009994:Osmolar Concentration; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D010952:Plasma Substitutes / Q000627:therapeutic use*; D000077325:Ringer's Lactate; D013552:Swine
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; D010952:Plasma Substitutes; D000077325:Ringer's Lactate; D010100:Oxygen