Oxygen transport dynamics of acellular hemoglobin solutions in an isovolemic hemodilution model in swine.

摘要: Background: One of the perceived advantages a hemoglobin-based blood substitute is provision oxygen-carrying capacity. Although hemodynamic response to infusion acellular hemoglobin solutions has been extensively studied, less known about oxygen transport dynamics such solutions. We hypothesized that are useful carriers in anemic states and higher P 50 O 2 more efficiently than low sought quantify an isovolemic hemodilution model swine. Methods: Eighteen swine were anesthetized, ventilated, instrumented for measurements withdrawal arterial mixed venous blood. The randomized into three groups progressively bled from initial hematocrit (Hct) 30% Hcts 19%, 13%, 8% using exchange with pyridoxalated polyoxyethylene conjugate (PHP, n = 6); identical solution without pyridoxalation, resulting (POE-Hb, or osmotically similar control pentastarch (PS, 6). Hemodynamic measurements, content, extraction ratio (ER), determined whole (WB), red cell (RBC) phase, plasma phase utilizing compartmentalized approach. Results: Mean pulmonary pressure was PHP POE-Hb PS group (p < 0.05). Cardiac index increased all groups, but significantly cardiac at 19% 13%. Oxygen delivery consumption maintained hematocrits baseline levels decreased Hct 0.05 vs. p PS). progressive both RBC phases maximum 39% 36% 8%. percent contribution total likewise values 52.7% (PHP) 68.2% (POE-Hb) 40.9% 39.3% consumption. Conclusion: Acellular provide significant consumption, particularly severe anemia, this exchange. differences two do not appear influence over range studied.