Effects of partial and total isovolemic exchange transfusion in fully conscious rats using pyridoxylated polyhemoglobin solution as a colloidal oxygen-delivering blood replacement fluid.
Stroma-free hemoglobin (SFHb) treated with pyridoxal 5'-phosphate (PP) was intermolecularly cross-linked with glutaraldehyde to give pyridoxylated polyhemoglobin (PP-PolyHb) solution (14.0 g/dl) with colloid osmotic pressure = 25 torr and a P50 = 20 torr. To evaluate PP-PolyHb as a blood substitute, fully conscious rats with chronic cannulations were subjected to blood replacement (30-100%) by a new continuous isovolemic exchange transfusion set up. Crystalline SFHb, PP-SFHb, PP-PolyHb, bovine serum albumin (BSA) and Ringer's solution were tested. Respiration, pulse and arterial blood pressure were more stable following transfusion with PP-PolyHb or PP-SFHb compared to BSA. By 7-8 days post-exchange, hematological changes returned to normal. Plasma retention of PP-PolyHb was 10-15 times longer than either crystalline SFHb or PP-SFHb for major blood exchanges. A T1/2 of 30 h was obtained for PP-PolyHb after total replacement. Long-term survival rates of 80, 63 and 50%, following replacement of 70, 85 and 100%, respectively, were significantly higher (p less than 0.05) than survival obtained for all other solutions tested. Superiority of PP-PolyHb over other fluids was clearly demonstrated.
Keipert
P E
PE
Artificial Cells & Organs Research Centre, Faculty of Medicine, McGill University, Montreal, Canada.
Chang
T M
TM
D000818:Animals; D001682:Biological Availability; D001802:Blood Substitutes; D003102:Colloids; D003243:Consciousness; D005078:Exchange Transfusion, Whole Blood; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D008297:Male; D010100:Oxygen / Q000378:metabolism*; D011732:Pyridoxal Phosphate / Q000031:analogs & derivatives*; D051381:Rats; D011919:Rats, Inbred Strains
D001802:Blood Substitutes; D003102:Colloids; D006454:Hemoglobins; C030939:polyhemoglobin-pyridoxal-5-phosphate; D011732:Pyridoxal Phosphate; D010100:Oxygen