Respiratory Channel

Prana vaha srotas is the life-carrying channel, the respiratory system. The mula (root) is the left chamber of the heart, which receives oxygenated blood from the lungs, and the maha srotas (the entire gastrointestinal tract). The marga (passage) is the respiratory tract and bronchial tree including the alveoli. The mukha (opening) is the nose. The important organs in this channel include the nose, nasal pharynx, larynx, trachea, bronchi, bronchioles, and alveoli.

Prana is located in the hypothalamus of the brain. Inhalation is governed by prana vayu, during which the intercostal muscles widen, the diaphragm descends, and air rushes into the respiratory passages. Exhalation is governed by udana vayu, which pushes out unwanted waste gases accumulated in the alveoli.

There is agni in prana vaha srotas that maintains the lumen of the alveoli. Avalambaka kapha, prana vayu, udana vayu, and vyana vayu are present in the heart and lungs. Sadhaka pitta is in the heart and brain—in the brain it processes information and words into knowledge, and in the heart it processes thoughts into feelings and emotions.

The transformation of food into energy and energy into vitality is governed by the digestive tract as well as prana vaha srotas. Through respiration, oxygen enters the alveoli, mixes with blood to become oxyhemoglobin, and is carried to all cells, tissues, organs, and systems. The lungs breathe not for themselves but for all cells in the body.

Prana vaha srotas is functionally connected to the colon. In Chinese medicine, the lung meridian connects to the colon meridian. If the colon is clogged, the lungs will not function properly. This connection exists because apana vayu in the colon, udana vayu in the lungs, and samana vayu in the intestines share functional integrity.

Whenever the colon is clogged, the person develops bad breath. Cleansing the colon with basti (medicated enema) will improve breathing. While modern anatomy sees no structural relationship between lungs and colon, there is a functional one: during exhalation, apana vayu pushes udana vayu upwards. In Ayurvedic terminology, exhalation is udana vayu (moving upwards and outwards), while in yoga terminology it is called apana. Ayurveda distinguishes udana vayu from apana vayu (which moves downwards and outwards).