1. Vascular resistance and the efficacy of red cell substitutes in a rat hemorrhage model.
- Author
-
Winslow RM, Gonzales A, Gonzales ML, Magde M, McCarthy M, Rohlfs RJ, and Vandegriff KD
- Subjects
- Animals, Blood Pressure drug effects, Blood Pressure physiology, Blood Viscosity drug effects, Blood Viscosity physiology, Blood Volume drug effects, Blood Volume physiology, Exchange Transfusion, Whole Blood, Heart Rate physiology, Hemodynamics drug effects, Hemodynamics physiology, Lactic Acid blood, Male, Oxidation-Reduction, Oxygen Consumption drug effects, Rats, Rats, Sprague-Dawley, Stroke Volume physiology, Blood Substitutes therapeutic use, Hemorrhage physiopathology, Hemorrhage therapy, Vascular Resistance drug effects, Vascular Resistance physiology
- Abstract
We have compared polyethylene glycol-modified bovine hemoglobin (PEG-Hb; high O2 affinity, high viscosity, high oncotic pressure) and human hemoglobin cross-linked between the alpha-chains (alpha alpha-Hb; low O2 affinity, low viscosity, low oncotic pressure) with a non-O2-carrying plasma expander (pentastarch, high viscosity and oncotic pressure) after a 50% (by volume) exchange transfusion followed by a severe (60% of blood volume) hemorrhage. Mean arterial pressure and systemic vascular resistance rose significantly in the alpha alpha-Hb but not in the PEG-Hb animals. Two-hour survival was greater in the PEG-Hb animals (93%) than in control (35%), pentastarch (8%), or alpha alpha-Hb (6%) animals. In the PEG-Hb animals, there was no disturbance of acid-base balance, significantly less accumulation of lactic acid, and higher cardiac output than in the other groups. The data suggest that the rise in vascular resistance that follows alpha alpha-Hb exchange transfusion offsets the additional O2 transport provided by the cell-free hemoglobin. When resistance does not rise, as with PEG-Hb, even relatively small amounts of cell-free hemoglobin appear to be a very effective blood replacement. more...
- Published
- 1998
- Full Text
- View/download PDF