title: Haemodynamic changes and skeletal muscle oxygen tension during complete blood exchange with ultrapurified polymerized bovine haemoglobin.
abstract: OBJECTIVE
  The study investigates the effect of continuous blood exchange with ultrapurified, polymerized bovine haemoglobin (UPBH) in comparison to hetastarch on haemodynamics, oxygen transport and skeletal muscle oxygen tension in a canine model.
  
  
  METHODS
  Sixteen anaesthetized beagle dogs underwent haemodilution with lactated Ringer's to a starting haematocrit of 20% followed by progressive blood exchange with 6% hetastarch 200,000/0.5 (HES, group 1) or UPBH (haemoglobin 13 +/- 1 g.dl-1, molecular weight (MW) 32-500,000, group 2) to haematocrit target levels of 15%, 10% and 5% or less.
  
  
  RESULTS
  Besides haemodynamics, skeletal muscle tissue oxygen tension (tPO2) was measured using a polarographic needle probe. In HES-treated animals, heart rate, cardiac output and blood flow were higher while systemic vascular resistance, systemic and regional arterio-venous oxygen difference (avDO2) and oxygen extraction ratios were lower when compared to the UPBH group. In spite of a higher final haematocrit of 5% in group 1, in comparison to group 2 with 2%, final muscular oxygen uptake (4.7 +/- 4 vs 10.1 +/- 2 ml.min-1) and mean tPO2 (11.8 +/- 2.3 vs 51.1 +/- 2.9 mm Hg) were lower in group 1 than in group 2. While tPO2 histograms were continuously shifted to lower oxygen tensions during progressive haemodilution with HES, UPBH-exchanged animals showed tPO2 histograms shifted to higher values than baseline.
  
  
  CONCLUSIONS
  In spite of vasoconstriction, UPBH provided more haemodynamic stability and enhanced skeletal muscle tPO2 during progressive blood exchange when compared to HES.
authors.affiliation: Department of Anaesthesiology, University Hospital Eppendorf, Hamburg, Germany.
authors.forename: T G
authors.initials: TG
authors.lastname: Standl
authors.forename: W
authors.initials: W
authors.lastname: Reeker
authors.forename: G
authors.initials: G
authors.lastname: Redmann
authors.forename: E
authors.initials: E
authors.lastname: Kochs
authors.forename: C
authors.initials: C
authors.lastname: Werner
authors.forename: J
authors.initials: J
authors.lastname: Schulte am Esch
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001802:Blood Substitutes / Q000494:pharmacology / Q000627:therapeutic use*; D002417:Cattle; D004285:Dogs; D005078:Exchange Transfusion, Whole Blood / Q000379:methods*; D006438:Hemodilution / Q000379:methods*; D006439:Hemodynamics / Q000187:drug effects; D006454:Hemoglobins / Q000494:pharmacology / Q000627:therapeutic use*; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology / Q000627:therapeutic use; D018482:Muscle, Skeletal / Q000187:drug effects*; D010101:Oxygen Consumption / Q000187:drug effects; D011108:Polymers; D018709:Statistics, Nonparametric
chemical_list: D001802:Blood Substitutes; D006454:Hemoglobins; D006895:Hydroxyethyl Starch Derivatives; D011108:Polymers