Neurologic Emergencies and Stabilization Flashcards
formula for CPP
CPP = MAP - ICP
Hallmark of severe TBI
Coma
The second key clinical manifestation is the development of intracranial hypertension
Cranial nerve dysfunction in intracranial hypertension
6th nerve palsy (lateral rectus palsy)
3rd cranial nerve compression
- anisocoria
- ptosis
- down-and-out position of globe
Conditions with “talk-and-die” scenario
- Epidural hematoma
- Diffuse cerebral edema
Peak ICP generally is seen ______ after TBI
48-72 hours
Conditions that may present with coma without increased ICP
Axonal injury
Brainstem injury
Age-dependent CPP targets
2-6 y/o: 50 mm Hg
7-10 y/o: 55 mm Hg
11-16 y/o: 65 mm Hg
First-tier therapy for intracranial hypertension
- Elevation of the head of the bed
- Midline positioning of the head
- Controlled mechanical ventilation
- Analgesia and sedation
- Neuromuscular blockade
- CSF drainage
- Osmolar agents (HTS, mannitol)
Dose of mannitol
0.25 - 1.0 g/kg IV
Dose of HTS
3% solution, 5-10 mL/kg IV
Use of hyperteonic saline is more common and has stronger literature support than mannitol, although both are used; these 2 agents can be used concurruently
When using osmolar agents, avoid serum osmality more than
320 mOsm/L
Second-tier therapies for refractory raised ICP
- Decompressive craniectomy
- Barbiturate (pentobarbital) infusion
- Mild hypothermia
- Hyperventilation
- Lumbar CSF drainage (only considered if a functioning ventriculostomy catheter is in place and basal cisterns are open)
Remarks on posttraumatic seizures
- Early posttraumatic seizures (<7 days) - anticonvulsant prophylaxis may be given with fosphenytoin, carbamazepine, or levetiracetam
- Late posttraumatic seizures (≥7 days) are NOT prevented by prophylactic anticonfulsants
Remarks on antifibrinolytic agents
Antifibrinolytic agents (tranexamic acid) reduce hemorrhage size, as well as the development of new focal ischemic cerebral lesions, and improve survival in adults with severe TBI
Most effective within 1 hour, effective up to within 3 hours after injury (CRASH-2 trial)