Does OxyVita, a New-Generation Hemoglobin-Based Oxygen Carrier, or Oxyglobin Acutely Interfere With Coagulation Compared With Normal Saline or 6% Hetastarch? An Ex Vivo Thromboelastography Study

Objectives: Because hetastarches have deleterious effects on coagulation that increase with molecular weight (MWt), risk of coagulopathy associated with a high MWt hemoglobin-based oxygen carrier (HBOC) was studied.Design: Preliminary laboratory study of donor blood using thromboelastography (TEG).Setting: University laboratory.Participants: Volunteer donor blood.Interventions: Experiments simulated hemodilution during clinical resuscitation of hemorrhagic shock with varying doses of HBOCs. Coagulopathy related to 1:11, 1:5, 1:2, or 1:1 dilution of whole blood with normal saline, 6% hetastarch (670 kilodaltons [kD]), hemoglobin glutamer-200 (HBOC-200, 200 kD), or OxyVita (OXYVITA Inc, New Windsor, NY) (a new-generation, zero-link polymerized bovine hemoglobin-based oxygen carrier, 33 megadaltons) were analyzed.Measurements and Main Results: At 2 lower levels of hemodilution, hetastarch, HBOC-200, and OxyVita produced equivalent reductions in maximum clot strength (TEG-MA and TEG-G) that reached statistical significance compared with whole blood and normal saline. At 2 higher dilutions, OxyVita and HBOC-200 impaired maximum clot strength compared with whole blood, normal saline, and hetastarch. Dilution with hetastarch had a greater effect on clot propagation (K and α) than either HBOC.Conclusions: OxyVita and HBOC-200, HBOCs with different MWt, had similar effects on coagulation as measured by TEG. The impairment of coagulation by HBOCs and hetastarch occurred at doses corresponding to 12 mL/kg or a blood volume replacement of 17%. The use of HBOCs at doses corresponding to 23 mL/kg or a blood volume replacement of 33% significantly decreased coagulation to levels associated with increased clinical bleeding in this preliminary study. Minimal coagulopathic effects are expected with use of OxyVita at the manufacturer’s anticipated effective dose of 10 g or 2 to 3 mL/kg.