Vagbhata considers that the pranavata is essential for the life and the udanavata for the strength of a person. If they are disturbed, there is danger to both life and strength. According to susruta, udanavata is that which course upwards.
Location of udanavata-
This important vata is located in nabhi uras and kanthadesa. According to vagbhata, the udanavata being located in uras moves in the regions of the throat, nose and nabhi. According to sarngadhara the udanavata is located in kanthadesha.
Function of udana vata-
According to charaka the normal functions of udanavata are- verbal expression (vakpravrtti), effort (prayatana), stimulation (Uraja), vitality (bala), complexion (Varna). The verbal expression is the main function of the udanavata; the other functions areaccomplished by the effective respiratory function during the production of speech by this vata. Susruta stressed the verbal expression while vagbhata added – Nourishment or soothing effect on the srotases and arousal of the mind, intellect, memory etc.