The phrenic nerve originates in the neck region of the spine. Its main role is to supply movement to the diaphragm, but it also supplies sensation to the chest and the upper part of the abdomen. The human body has two phrenic nerves --- a left and a right. They both follow different paths; however, they both begin in the C3-C5 vertebral region of the neck. The phrenic nerves help the diaphragm contract, which is very important in the breathing process.
Phrenic-Nerve Damage
Phrenic-nerve damage typically occurs from trauma to the cervical spine. It can also result from a surgical problem, an accident or a abnormality in the surrounding tissue. Ordinarily, if one phrenic nerve is intact, you will still be able to breathe, though it will probably be a difficult and labored breathing pattern.
Sensory fibers comprise the phrenic nerve. They are responsible for supplying sensation to the pericardium, the sac in which the heart sits. The phrenic nerve also supplies sensation to other areas of the body like the heart and lungs. In addition, the phrenic nerve controls feeling in the abdominal cavity. When the phrenic nerve is damaged, these areas of the body lose sensation and are unable to perform properly.
Surgery
Neurosurgeon Dr. Abbott Krieger has been working on a technique to repair the phrenic nerve by way of grafting. He uses a living intercostal nerve and grafts it to the phrenic nerve. Approximately six months later, nerve regeneration occurs and the phrenic nerve comes to life, so to speak. This regeneration helps the phrenic nerve regain electrical function.
A pacemaker, similar to the kind used for cardiac patients, is then inserted to help the fused nerve send correct "breathing" signals to the diaphragm, which is called "pacing the phrenic nerve." This fairly new innovation has showed promising results, says Dr. Krieger, and is a viable alternative to living on a ventilator, which can shorten your life due to possible complications.
At this time, surgery for phrenic-nerve damage is the only treatment known to repair it.
