Abstract 16: Intraaortic Aqueous Oxygen Infusion in a Swine Model of Acute Isovolemic Anemia
Background: Intracoronary perfusion with hyperbaric aqueous oxygen (AO) during reperfusion in anterior STEMI patients has been shown to reduce infarct size. Technical limitations of the method preclude scaling up AO delivery for potential treatment of systemic hypoxia.
Methods: Prototype catheters (5F) with multi- AO delivery ports were fabricated to provide bubble-less AO infusion into blood. Juvenile domestic swine (n = 10, mean weight 30 kg), were anesthetized and ventilated to maintain arterial O2 sat > 95%. An AO catheter was advanced retrograde into the descending aorta via femoral arterial access. After establishing a 2-hour stable hemodynamic baseline, rapid simultaneous 1:1 blood exchanges with lactated Ringer’s solution were performed to reduce Hb to <5 g%. In the treatment group (n =3), AO infusion (20 mL/O2/min) was initiated at Hb <10 g% and delivered into the aorta for one hour. Control swine (n = 7) received sham AO infusion. In four of these controls, introduction of high flow AO infusion (35 mL/O2/min) was initiated after hemodynamic collapse.
Results: During AO infusion, femoral arterial PO2 increased in the treatment group by a mean of 218±40 mmHg compared to baseline values. No adverse effects on LV function and hemodynamics were noted. Echocardiography showed no evidence of intracardiac microbubbles. At Hb < 3.4 g %, discontinuation of AO infusion was associated with abrupt hemodynamic deterioration. In the control group, introduction of high flow AO infusion, after hemodynamic collapse, resulted in normalization of hemodynamics with an increase in femoral arterial PO2 by a mean of 527±57 mmHg.
Conclusions: Intra-aortic AO infusion with a prototype multiport catheter was effective at increasing systemic oxygen delivery, without evidence of microbubble formation or adverse effects on hemodynamics. Furthermore, introduction of high flow AO infusion in controls after hemodynamic collapse resulted in normalization of hemodynamics.
- © 2013 by American Heart Association, Inc.