title: The effects of hemodilution with Hemolink upon hemodynamics and blood flow distribution in anesthetized dogs.
abstract: Hemoglobin based oxygen-carrying solutions (HBOCs) as hemoglobin replacement therapeutics are being tested for clinical use. Some of these products are associated with elevations in both systemic and pulmonary vascular resistances but their effect on the distribution of blood flow to major organs in larger animals have not been extensively described. We tested two formulations of o-raffinose cross-linked human hemoglobin, Hemolink (frozen-Hemolink-1 and refrigerated Hemolink-2) and compared them to Pentaspan, a colloid volume expander in extensive clinical use. Cardiovascular measurements and the distribution of blood flow (radionuclide-labeled microspheres) to the major organs were determined in Beagle dogs (n = 5 per group). After baseline measurements, either Hemolink-1, Hemolink-2, or Pentaspan was exchange transfused in an isovolemic manner (resulting in hematocrit reduction to approximately 20-25%); measurements were made 30, 60, 120 and 180 min post-exchange. There was no significant difference in cardiac output, mean arterial pressures and systemic or pulmonary vascular resistances after exchange in any of the three groups. Myocardial blood flow increased in all three groups post-exchange but the increase was more sustained in the Hemolink groups. Endocardial/epicardial flow ratios were also maintained after exchange in all groups. Thus, Hemolink is ideally suited for volume replacement when used in conjunction with acute normovolemic hemodilution because under these circumstances, the adverse hemodynamic effects are alleviated while extra hemoglobin is added to the blood.
authors.affiliation: Department of Medicine, Faculty of Medicine, Laval University, Quebec, QC, Canada.
authors.forename: J G
authors.initials: JG
authors.lastname: Kingma
authors.forename: Reena
authors.initials: R
authors.lastname: Sandhu
authors.forename: N D
authors.initials: ND
authors.lastname: Hamelin
authors.forename: D
authors.initials: D
authors.lastname: Gendron
authors.forename: Y
authors.initials: Y
authors.lastname: Trudel
authors.forename: M
authors.initials: M
authors.lastname: Bosa
authors.forename: R
authors.initials: R
authors.lastname: Stewart
authors.forename: M B
authors.initials: MB
authors.lastname: Fargey
authors.forename: G P
authors.initials: GP
authors.lastname: Biro
mesh_terms: D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure; D002245:Carbon Dioxide / Q000097:blood; D004285:Dogs; D005615:Freezing; D006339:Heart Rate; D006400:Hematocrit; D006438:Hemodilution / Q000379:methods*; D006439:Hemodynamics; D006454:Hemoglobins; D010100:Oxygen / Q000097:blood; D011887:Raffinose / Q000031:analogs & derivatives*; D012039:Regional Blood Flow; D013318:Stroke Volume; D014655:Vascular Resistance
chemical_list: D006454:Hemoglobins; C097124:O-raffinose cross-linked human hemoglobin; D002245:Carbon Dioxide; D011887:Raffinose; D010100:Oxygen