More complications of TBI

1. How does tentorial (uncal) herniation occur?
2. What symptoms are produced from uncal herniation?
3. Why does post-TBI HTN occur?
4. What is the recommended treatment for post-TBI HTN?

Answers:
1. The medial part of one temporal lobe (uncus and parahippocampal gyrus) is displaced over the edge of the ipsilateral tentorium cerebelli as a result of increased supratentorial pressure from hematoma or brain tumor.
2. Stretching of CN III causes ipsilateral pupil dilation or third nerve palsy; ipsilateral hemiparesis from pressure on corticospinal tract; contralateral hemiparesis due to pressure on precentral motor cortex or internal capsule; late reduced consciousness.
3. Sympathetic hyperactivity, demonstrated by increased plasma and urine catecholamines.
4. Propranolol.