Recurrent Laryngeal Nerve

The recurrent laryngeal nerve is one of the branches of the vagus nerve, an important nerve of the nervous system. The vagus nerve is the tenth cranial nerve and which originates in the brain stem. The vagus nerve divides into many different branches that supply different parts of the body. The recurrent laryngeal nerve is responsible for supplying motor function to the main area that is supposed to generate our voice, the larynx. Given below are some more details regarding this important nerve.

Path of Recurrent Laryngeal Nerve
The name of the nerve is defined by its path. This nerve was called 'recurrent' because of the route that this nerve takes in the head, neck and thoracic region. This nerve innervates the main laryngeal muscles, it descends in the thorax and then returns from the region between the wind pipe and food pipe, and thus re-enters the neck. This nerve further divides into the left and right recurrent laryngeal nerve. The left branch of the nerve breaks off from the vagus and finds its way around the main arch of the aorta. The right branch goes around the right subclavian artery. Basically, this nerve is responsible for innervation of the very important intrinsic muscles of the larynx, except for the cricothyroid muscle. This nerve is responsible for producing sounds because it brings about both, adduction and abduction of the vocal folds.

Recurrent Laryngeal Nerve Block
This procedure is done to anesthetize the nerve and is done by placing the patient in a supine position. Local anesthetic solution is taken and drawn into a sterile syringe. Now the sternocleidomastoid muscle's medial border is identified and the needle is inserted in a manner that it is perpendicular to the skin. After this, aspiration should be done to ensure that no blood comes out. If the aspiration is clear, then the solution is slowly injected completely.

Recurrent Laryngeal Nerve Block Complications
There are quite a few risks of this procedure, due to the proximity of this nerve to many important structures like the carotid artery, jugular vein and the numerous vital structures in the neck region. Thus, due to the many blood vessels in this region, there are high chances that there are complications like hematoma formation. Thus, one should always keep anticoagulants at hand while doing this procedure. If a hematoma does take place, then an ice pack helps to decrease the amount of blood. To decrease the chances of such complications, one can always, immediately after giving the injection, apply manual pressure at the site of injection.

One should not give a bilateral recurrent laryngeal nerve block in every situation. As mentioned earlier, because this vital nerve supplies the intrinsic muscles of the larynx besides the cricothyroid, a bilateral nerve block is only meant for those patients who have undergone a laryngectomy or a tracheostomy. This is because, the resulting bilateral block to recurrent laryngeal nerve, paralysis of the vocal cords may lead to airway obstruction, which could eventually lead to airways obstruction.

This was all about the recurrent laryngeal nerve, an important nerve of the body. This is an important nerve and its pathologic significance is huge. Paralysis of the larynx, which can appear due to damage to this nerve, is a serious condition and may occur due to a tumor in the chest region or at times, if there is an aneurysm in the aorta, it may compress the left branch of the nerve. Some people claim that the recurrent laryngeal nerve evolution is to blame for the topsy-turvy path taken by this nerve. This is further validated by the fact that there is an extreme detour of this nerve seen in giraffes. However, many scientists dismiss such claims as wishful thinking.