title: High molecular weight hydroxyethyl starch solutions are not more effective than a low wmolecular weight hydroxyethyl starch solution  in a porcine model of septic shock.
abstract: BACKGROUND
  There is evidence that suggests that early fluid resuscitation is beneficial in the treatment of sepsis. We previously demonstrated that hydroxyethyl starch (HES) 130/0.42 attenuated capillary leakage better than HES 200/0.5. Using a similar porcine fecal sepsis model, we tested the effects of two new synthetic high molecular weight (700 kDa) hydroxyethyl starches with the same molar substitution of 0.42 but with a different C2/C6 ratio compared to 6% HES 130/0.42 on plasma volume (PV), systemic and tissue oxygenation.
  
  
  METHODS
  This was a prospective, randomized, controlled animal study. Twenty-five anesthetized and mechanically ventilated pigs (28.4±2.3 kg) were observed over 8 h. Septic shock was induced with fecal peritonitis. Animals were randomized for volume-replacement therapy with HES 700/0.42 C2/C6/2.5:1 (N.=5), HES 700/0.42 C2/C6/6:1 (N.=5), HES 130/0.42 C2/C6/5:1 (N.=5) or Ringer’s Solution (RS, N.=5), and compared to non-septic controls receiving RS (N.=5). The albumin escape rate (AER) was calculated and plasma volume was determined at the end of the study. Tissue Oxygen Saturation was measured with the InSpectra™ Device (InSpectra Tissue Spectrometer, Hutchinson Technology Inc., Hutchinson, MN, USA).
  
  
  RESULTS
  The AER increased in all groups compared to control. All colloids (HES 700/6:1 68±15; HES 130 67±4; HES 700/2.5:1 71±12; P<0.05) but not RS (44±7) stabilized PV (mL/kg BW) after eight hours of sepsis. Systemic oxygenation was significantly lower in the RS group (44±17%; P<0.05) compared to all other groups at study end (P<0.05).
  
  
  CONCLUSIONS
  In this porcine fecal peritonitis model, the high molecular weight artificial colloids HES 700/2.5:1 and HES 700/6:1 were not more effective in maintaining plasma volume and systemic and tissue oxygenation than HES 130. In comparison to crystalloid RS, all HES solutions were more effective at maintaining plasma volume, mean arterial pressure (MAP), and systemic and tissue oxygenation.
authors.affiliation: Department of Intensive Care and Intermediate Care, RWTH University Hospital Aachen, Aachen, Germany. tsimon@ukaachen.de
authors.forename: T-P
authors.initials: TP
authors.lastname: Simon
authors.forename: T
authors.initials: T
authors.lastname: Schuerholz
authors.forename: S P
authors.initials: SP
authors.lastname: Haugvik
authors.forename: C
authors.initials: C
authors.lastname: Forberger
authors.forename: M-A
authors.initials: MA
authors.lastname: Burmeister
authors.forename: G
authors.initials: G
authors.lastname: Marx
mesh_terms: D000758:Anesthesia; D000818:Animals; D002196:Capillaries / Q000187:drug effects; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006895:Hydroxyethyl Starch Derivatives / Q000737:chemistry* / Q000627:therapeutic use*; D008365:Manometry; D008970:Molecular Weight; D010101:Oxygen Consumption / Q000187:drug effects; D019999:Pharmaceutical Solutions; D010952:Plasma Substitutes / Q000737:chemistry* / Q000627:therapeutic use*; D010953:Plasma Volume / Q000187:drug effects; D012709:Serum Albumin / Q000378:metabolism; D012772:Shock, Septic / Q000188:drug therapy*; D013552:Swine
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D019999:Pharmaceutical Solutions; D010952:Plasma Substitutes; D012709:Serum Albumin