Ch59 Head injury Long term management

Question 1

What are the calorific requirements following head injury?

Answer 1

100% if paralysed

140% if not paralysed

Mortality is reduced if this is achieved by day 7 and started within 72 hours.

>15% should of calories should be protein.

Enteral route is prefered

Question 2

How is the calorific requirement calculated?

Answer 2

As the basal energy expenditure (BEE) using the Harris-Benedict equation.

Question 3

Why does urea increase following trauma?

Answer 3

Catabolic state breaks down proteins and Nitrogen is excreted as urea. To replace this >15% of the BEE should be protein.

Question 4

How do you differentiate post-traumatic hydrocephalus from ex vacuo hydrocephalus?

Answer 4

High pressure on >1 LP Papilloedema Headaches Transependymal oedema Neurological decline or altered rehabilitation

Question 5

Which basal cisterns are viewed following trauma?

Answer 5

The quadrigeminal and 2x ambient cisterns. Correlated with mortality.

Question 6

What is the biparietal diameter?

Answer 6

A measure of midline shift. Measure the inner skull vault distance at the level of the foramen of Monroe, dividing by 2 and subtracting the distance of the septum pellucidum from the inner table of the vault.

Question 7

What is a genetic risk factor for severe head injury?

Answer 7

Apolipoprotein E4 (also risk factor for Alzheimer’s!)

Question 8

What are the delayed complications of head injury?

Answer 8

Seizures (10% severe, 5% moderate and 0% mild)

Encephalopathy

Pituitary deficiencies

Question 9

What are the histological findings in chronic traumatic encephalopathy?

Answer 9

Beta-Amyloid plaques and cererbral amyloid angiopathy - similar to Alzheimer’s disease. Present with clinical features of Parkinsonism.

Question 10

What underlies the risk of second impact syndrome?

Answer 10

Dysfunction of cerebral autoregulation causing diffuse cerebellar swelling