istmikunärv

The istmikunärv, also known as the phrenic nerve, is a nerve that originates in the neck and runs down through the chest to the diaphragm. It is the sole motor nerve supply to the diaphragm, which is the primary muscle responsible for breathing. The phrenic nerve also carries sensory information from the diaphragm and the mediastinum.

The phrenic nerve is formed from nerve roots C3, C4, and C5 in the cervical spine. It descends through the neck, passing between the anterior and middle scalene muscles. In the thorax, it runs along the pericardium, the sac that surrounds the heart, before finally reaching the diaphragm.

Damage to the phrenic nerve can have serious consequences. Unilateral phrenic nerve palsy, affecting one side of the diaphragm, can lead to shortness of breath, particularly with exertion. Bilateral phrenic nerve palsy, affecting both sides, can cause significant respiratory distress and may require mechanical ventilation. Causes of phrenic nerve damage include trauma, surgery, infections, and certain neurological conditions. Treatment depends on the underlying cause and may involve physical therapy or, in severe cases, surgical intervention.