Cerebral oxygen uptake (vo2cer) decreases during acute hypoxemia in the llama fetus

Abstract

Cerebral blood flow (CBF) in the llama fetus does not augment during acute hypoxemia, decreasing cerebral oxygen delivery. To investigate whether VO2 cer could be maintained during hypoxemia by increasing cerebral oxygen extraction, we placed catheters in ascending and descending aorta, inferior vena cava and sagital sinus in 7 llama fetuses (0.6-0.7 of gestation). At 4th days post-surgery, measurements were made of hemoglobin saturation, carotid (Ca O2) and sagital (CsO2) oxygen content, CBF (radiolabelled micropheres) basally and after 60 min of hypoxemia) (15% Hb sat in ascending aorta). Results: means ± SEM; *p<0.05 Basal vs. Hypoxemia.