Quantification of Blood Oxygenation & Flow in Response to Apneic Challenge

Zachary B. Rodgers¹, Michael C. Langham¹, Jeremy F. Magland¹, Felix W. Wehrli¹

Blood flow velocity and oxygenation in the femoral vessels and superior sagittal sinus were quantified to evaluate physiological responses during apneic challenge. During apnea, the arteriovenous difference narrowed, with femoral arterial HbO2 decreasing to 85-90% and venous HbO2 increasing approximately 5 %HbO2. While velocity decreased in the femoral vessels, it doubled in the SSS, consistent with the previously described normal physiologic preservation of central O2 delivery during apnea. The technique described could be used to characterize the apneic response in diseases such as sleep apnea and chronic obstructive pulmonary disease, potentially serving as a non-invasive diagnostic and prognostic tool.