6. Head Injuries Flashcards
Epidural haematoma most likely from what vessels?
Meningeal arteries.
Most common bleeder is middle meningeal artery.
Or, laceration of venous sinuses.
What is uncal herniation?
Herniation of the uncus (medial part of the temporal lobe) through the tentorial notch.
Compression at the midbrain will result in weakness on which side of the body?
Opposite side
What are the classic clinical signs of uncal herniation?
Pupillary dilatation on the injured side.
Motor weakness on the opposite side.
Typical ICP?
10mmHg
Why must MAP be maintained within normal range during TBI
If MAP is too low, there is underperfusion of the brain, leading to ischaemia and infarction.
If MAP is too high, brain swelling occurs with elevated ICP.
Categories of brain injury based on GCS:
13-15: mild
9-12: moderate
<8: severe
Target PCO2 in head injured patients
35mm Hg
In other words, avoid hyperventilation unless there are clear signs of current herniation
What treatments are given in severely head injured patients?
These are usually given after consultation with a neurosurgeon:
- Mannitol
- Hypertonic saline
What effect does brain injury have on BP?
Usually none.
Hypotension can occur in the terminal stages when medullary failure supervenes.
Early sign of uncal hernaiation
Dilation of pupil, loss of pupillary response to light.
Anticoagulation reversal for: antiplatelet therapy
Platelets
Anticoagulation reversal for: warfarin
FFP, vitamin K, prothrombin complex concentrate, factor VII
Anticoagulation reversal for: heparin
Protamine sulfate
Anticoagulation reversal for: LMWH (e.g. enoxaparin)
Protamine sulfate
Anticoagulation reversal for: direct thrombin inhibitors
Idarucizumab
Anticoagulation reversal for: rivaroxaban
None
Main contraindication to mannitol
Hypotensive patients (mannitol doesn’t work in hypovolaemic patients; mannitol is a potent diuretic)
When should one give mannitol?
Acute neuro deterioration (inc. dilated pupil, hemiparesis, LoC)
When should anticonvulsants be used in head injured pateints?
Only when absolutely necessary.
Not for routine use, as they can inhibit brain recovery.
Typical anticonvulsants used in head injured patients with seizures
Phenytoin. 2g, given at 50mg/minute.
Can supplment with diazepam or lorazepam.
Why is it important to control seizures?
Prolonged seizures can cause secondary brain injury.
What is the role of antibiotics in head injured patients?
Broad spectrum Abx should be given prophylactically in patients with penetrating head injury
