If the spinal cord injury occurs in C-3 or higher, the phrenic nerve is no longer stimulated and the diaphragm does not function. This means the individual will need mechanical assistance - a ventilator - to breathe.

     Persons with spinal cord injury at the mid-thoracic level and higher will have trouble taking a deep breath and exhaling forcefully. They have also lost the ability to forcefully cough or to cough with even normal force because of the loss of the intercostal and/or abdominal muscles. This loss of the ability to cough can lead to lung congestion and respiratory infections.