1531 - Autonomic Dysfunction in Acute Concussion Patients: A Novel Case Study

Case Diagnosis: A 15 year-old woman with no past medical history is diagnosed with an acute concussion due to a soccer injury. She presented with temporal headaches, dizziness, cognitive/physical fatigue, poor concentration, insomnia, blurry vision and cervicalgia. She had been taking nortriptyline daily and was in vision therapy.

Case Description: On exam, she was found to have pupillary asymmetry (sluggish and less reactive right pupil), significant nystagmus with left sided gaze, interrupted saccades in horizontal movements and esotropia in the left eye with vertical movements. Cognitive exam was significant for impaired attention and short-term recall. She had significant balance impairment. Her blood pressure was measured in supine position as 124/70 mm Hg with heart rate of 70 bpm. After standing, her blood pressure increased significantly to 158/119 mm Hg with a heart rate of 113 bpm. After one minute of standing, her heart rate increased further to 126 bpm.

Discussions: She was started on propranolol 10 mg twice daily and amantadine 100 mg twice daily for cognitive fatigue and impaired attention. A videonystagmography and rotary chair test was performed: it indicated both central dysfunction and mixed positional nystagmus consistent with vestibular dysfunction. She was enrolled in a vestibular program. She was evaluated by a neuro-optometrist and prescribed prism glasses. Her blood pressure/heart rate variability improved with only residual photophobia and noise sensitivity.

Conclusions: Autonomic dysfunction after an acute concussion is often underdiagnosed given the constellation of symptoms including visual, cognitive, vestibular and functional impairments. Among patients who demonstrate significant blood pressure and heart rate variability, vestibular dysfunction is often found on videonystagmography and rotary chair test assessment. In addition, subjective dizziness and vertigo present challenges in reintegrating patients to their community. When properly identified, anti-hypertensive medications such as beta-blockers and vestibular rehabilitation to address visuospatial autonomic sensitivity have shown benefit in this unique population.