Hemoglobin-based oxygen carrier HBOC-201 provides higher and faster increase in oxygen tension in skeletal muscle of anemic dogs than do stored red blood cells

Background: Increasing need for and potential shortage of blood products have intensified the search for alternative oxygen carriers. A solution to this problem could be use of the bovine hemoglobin-based oxygen carrier HBOC-201. While hemodynamic reactions to cell-free hemoglobin have been studied, little knowledge exists about tissue oxygenation properties of hemoglobin solutions, especially in comparison with red blood cells (RBCs). Study design and methods: Tissue oxygenation in skeletal muscle of 12 anesthetized dogs was examined after decrease of hemoglobin concentrations by means of hemodilution to hematocrit 10% and subsequent transfusion with either HBOC-201 or autologous banked RBCs. In addition to hemodynamic parameters, blood gas concentrations and oxygen content in arterial and muscular venous blood, tissue oxygen tension (tPo(2)) were measured in the gastrocnemius muscle with a polarographic needle probe. Results: Hemodilution increased muscular blood flow and oxygen extraction and decreased tPo(2). Transfusion decreased muscular oxygen extraction in the REC group but not in the HBOC-201 group (P < .01). The 10th percentile of tPo(2) increased by 400% after the first dose of HBOC-201 (P < .001 vs posthemodilution) but only by 33% after equivalent RBC transfusion (P < .01 vs HBOC-201). Increases in the 50th (120%, P < .05) and 90th (31%) percentiles and all percentiles of tPo(2) after the second and third HBOC-201 dose were less pronounced but higher than in the RBC group. Conclusion: Compared with RBC transfusion, infusion of low doses of HBOC-201 maintain enhanced oxygen extraction after extended hemodilution and provide faster and higher increase in muscular tissue Po-2.