The Philosophy of the Upanishads c11.s2.t4.26

c11.s2.t4.26

(5) *Udâna*, or “up-breathing,” according to the usual view maintained also in Pras'na 3. 7, conducts the soul from the body at death, while according to Pras'na 4. 4 already in deep sleep it guides to Brahman; it is maintained however in Maitr. 2. 6 that udâna “either brings up again or swallows down that which is eaten and drunk.” Elsewhere it is represented as dwelling in the throat.¹ Similarly also in Vedântasâra 97, where it is otherwise explained as the wind of exit.