Bronchial Branches of Vagus Nerve (Left)

Origin

The bronchial branches of the vagus nerve are short branches that emerge from the vagus nerve roughly lateral to the carina.

Course

The bronchial branches of the vagus nerve descend from their origin lateral to the carina to the anterior and posterior surfaces of the left and right bronchi. This is the approximate location of the anterior and posterior pulmonary plexuses. The pulmonary plexus is in part a continuation of the cardiac plexus. Therefore, many of the branches that contribute to the cardiac plexus may also send fibers to the pulmonary plexus.

Branches

The bronchial branches of the vagus nerve contribute to the formation of the anterior and posterior pulmonary plexuses.

Supplied Structures & Function

The bronchial branches of the vagus nerve contain parasympathetic preganglionic fibers and visceral afferents that travel to the brainstem via the vagus nerve. The parasympathetic efferent fibers cause contraction of bronchial smooth muscle, constricting the airways (Chila, 2010). Other efferents target secretory glands in the epithelium, increasing the production of serous secretions. Finally, parasympathetic efferents of the bronchial branches of the vagus nerve have been implicated in causing vasodilation of pulmonary arteries and arterioles (Mazzone and Canning, 2013).

Visceral afferents that travel via the bronchial branches of the vagus nerve carry sensory information pertaining to stretch and irritation. This feedback is involved in regulation of bronchial smooth muscle tone and the cough reflex, respectively.

List of Clinical Correlates

—Cough reflex

References

Chila, A. G. (2010) Foundations of Osteopathic Medicine. 3rd edn.: Lippincott Williams & Wilkins.