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Medical Term:


Pronunciation: or'tho-de-oks'e-a

Definition: Fall in arterial blood oxygen on assuming the upright posture. Usually caused by right-to-left cardiac or vascular shunting with a posturally induced fall in left-sided pressure permitting a corresponding gradient across the shunt.

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.