1127 - The Pacer Test: A rare case of a diaphragm pacer causing autonomic dysreflexia in a cervical spinal cord injury patient

45-year-old male presents after a fall down stairs causing a C2 burst fracture, right vertebral artery dissection, displaced fracture of right C6/7 transverse process and C7 superior articular process. He underwent C1–C3 fusion, C6 open reduction, and C1–T2 posterior fusion then discharged as ventilator-dependent to inpatient rehabilitation. The patient was diagnosed as C2 ASIA B and throughout his rehab course remained unable to generate adequate tidal volumes, prompting evaluation and implantation of a diaphragm pacing system. The patient’s course was complicated by autonomic dysreflexia (AD) due to various noxious stimuli. Shortly after implantation, the patient had an AD episode with hypertension to 174/100. The team attempted to neutralize stimuli including sitting the patient up, removing clothes, flushing the foley and performing a bowel routine. Despite these attempts, the patient continued to be hypertensive and unstable. The decision was made to turn off the diaphragm pacer and the patient's hypertension stabilized. 

Discussions:

Autonomic dysreflexia can be caused by a myriad of noxious stimuli. This patient had many reasons for discomfort, but this particular episode seemed to subside after turning off a diaphragmatic pacer which may have been causing the patient distress leading to the episode. After this episode, the patient was started on scheduled tylenol for possible assistance of pacer discomfort, which seemed to help stabilize his AD episodes that did not have another more common etiology. 

Conclusions:

This case highlights a rare but important potential etiology of autonomic dysreflexia in cervical spinal cord injury patients: diaphragmatic pacer related discomfort. This highlights the range of stimuli which can induce AD and as well as the important role of rehabilitation providers in identifying and treating less common triggers.