Head injury Flashcards
Difference between primary and secondary brain injury?
Primary- From time of injury
Secondary- Due to consequences of injury, partly preventable
Pathophysiology of brain injury?
Release of excitatory amino acids
Bind to receptors eg NMDA
Release of intracellular calcium–>Activation of phospholipases, breakdown cell membrane, cell swelling, activation of apoptosis
What is the relationship between the brain, circulating blood, CSF and ICP
An increase in volume of brain, blood or csf must produce a decrease in another component, otherwise increased ICP
How is Cerebral perfusion pressure calculated and what is the target CPP after head injury?
CPP= MAP- ICP
Aim for >60mmHg
ie MAP >80mmHg and ICP
What is normal adult ICP
9-11 mmHg
What do “raccoon/panda eyes” signify?
A fracture in the anterior cranial fossa
What does “battle sign” signify?
A fracture in the middle cranial fossa
How is consciousness assessed?
Glasgow coma scale
Which 3 factors does the GCS take into account?
Eye opening
Verbal response
Best motor response
What causes death in patients with head injury?
Hypoxia
Hypotension
Raised ICP
When should CT be requested in patient with head trauma
Skull fracture
Not orientated (GCS
Which 5 things should be carried out after head injury?
Sedation
Ventilation
Maintain BP
Maintain glucose
Maintain temperature
What desirable effects does sedation have for a patient following head injury?
Reduces cerebral metabolic rate
Reduces cerebral blood flow
Reduces ICP
What are the late effects of head injury?
Epilepsy
CSF Leak
Cognitive problems
