A 73-year-old man attended the ED following an assault where he sustained multiple traumatic blows to the head. He was alert, complained of headache but provided a detailed account. There were facial injuries but no clinical signs of cranial or skull base fractures. There was injury to the right eye, in which he had pre-existing visual impairment from previous injury. Vision was normal in the left. Right pupillary light reflex was absent but left was normal. The remainder of the neurological examination was unremarkable. CT-Head identified a small traumatic subarachnoid hemorrhage over the left cerebral convexity and a small contusion in the left temporo-parietal region. Vitreous hemorrhage was evident in the right eye. 

Clinically stable, follow-up CT on day 3 showed small intra-cerebral haemorrhage within the contusion, with minimal mass effect. However, on day 8, his GCS dropped and he was admitted to the ITU for airway management. Both pupils were non-responsive to light. Expansion of haemorrhage was suspected, however repeat CT was stable. EEG showed slowing over the left hemisphere without epileptiform activity. MRI excluded alternative causes for his neurological status such as brainstem ischaemia.

With no clinical improvement, formal brainstem death testing was initiated. No potential confounders were recognised. The pupillary, corneal, oculocephalic, cough and gag reflexes were absent. Unexpectedly, deep tendon reflexes were absent in all limbs. A peripheral nerve stimulator using a train-of-four test protocol found no response. Post-traumatic Guillain-Barré syndrome (GBS) was suspected. 

Intravenous immunoglobulin was commenced. Nerve conduction studies found absent motor and sensory responses in all limbs. EMG showed fibrillation potentials and sharp waves. These findings were consistent with acute motor-sensory axonal neuropathy (AMSAN) variant of GBS. Serum Anti-GM1 antibodies were identified. After multiple rounds of plasmapheresis the patient was weaned from the ventilator. Nevertheless, severe neurological disability remained.