Electrophrenic respiration after intercostal to phrenic nerve anastomosis in a patient with anterior spinal artery syndrome: technical case report.

Long-term positive pressure mechanical ventilation has been the standard of care for patients with respiratory insufficiency caused by high cervical spine injury. Stimulation of the phrenic nerves, and thus the diaphragm, with an implanted phrenic nerve pacemaker has provided adequate ventilation and an alternative to the standard. Diaphragmatic pacing, also known as electrophrenic respiration, requires an intact phrenic nerve to act as a conduit for the applied stimulus. Propagation of the stimulus is impossible if the injury sustained has led to axonal loss in the phrenic nerve. This may be expected if the damage to the spinal cord is at the C3-C5 level. If the cell bodies of the motor neurons in this region have been damaged, or direct injury to the phrenic nerve has occurred, then diaphragmatic pacing is not feasible by the traditional method. Microsurgical repair of peripheral nerves and nerve grafting have provided the impetus for research into anastomosis of a viable intercostal nerve to a nonfunctional phrenic nerve, with subsequent reinnervation of the diaphragm. Once successful axonal regeneration and diaphragmatic reinnervation have occurred, the distal phrenic nerve may then be paced. This case documents the first successful institution of electrophrenic respiration after intercostal to phrenic nerve anastomosis.