Acute Normovolemic Hemodilution-assisted Terminal Blood Procurement in Swine for Ex Vivo Organ Perfusion

Swine (Sus scrofa domesticus) are commonly used large animal subjects for the study of disease and preclinical therapies. Organ machine perfusion is a therapy that has gained momentum as a research platform for the study of ex vivo organ preservation and therapeutics. However, complex perfusion circuits and research protocols often require large volumes of blood as perfusate. Here, we report a technique for increasing terminal blood yield during swine organ and blood procurement; our method involves acute normovolemic hemodilution and exsanguination via the femoral artery. We collected a total of 47 ± 4 mL/kg of blood and 4.3 ± 0.6 g/kg of hemoglobin, representing 73% ± 6% of the estimated blood volume and 64% ± 8% of the total estimated intravascular hemoglobin (n = 4). Neither pH, lactate, nor pO2 levels changed significantly during blood procurement. Acute normovolemic hemodilution is an effective method for increasing RBC and hemoglobin yield during blood procurement in swine.