Raised ICP

Question 1

What fluids are present in the brain?

Answer 1

Brain tissue + ICF
ECF
Blood
CSF

Question 2

What is normal ICP?

Answer 2

0-10 mmHg

Question 3

How do you raise ICP naturally?

Answer 3

cough
sneeze
valasalve maneouvre

Question 4

How can you manually lower your ICP by yourself?

Answer 4

Lie from standing

Question 5

What mass could cause a raised ICP?

Answer 5

tumour, haematoma, abscess

Question 6

Aside from a mass, what can cause raised ICP?

Answer 6

traumatic brain injury

hydrocephalus

Question 7

How is the ICP kept constant?

Answer 7

1. chemoregulation (pCO2, pH, pO2, metabolic byproducts)

2. autoregulation (smooth muscle changes, contraction and relaxation)

Question 8

How does body cope with raised ICP? (compensation mechanisms)

Answer 8

reduce volume of CSF (re-direct into spinal canal)
reduce cerebral blood volume
reduce ECF

Question 9

Which special adaptation in babies/infants can reduce raised ICP?

Answer 9

skull expansion- fontanelle become swollen, skull sutures splay

Question 10

What are the clinical symptoms of raised ICP?

Answer 10

Headache
Disturbed sleep
Nausea and vomiting
Blurred vision
Drowsiness/coma
Delayed development (in children)

Question 11

WHat are the features of raised ICP headache?

Answer 11

generalised
aggravated by bending or coughing
worse in morning on wakening from sleep
severity gradually gets worse

Question 12

What are the signs of raised ICP?

Answer 12

decreased GCS
papilloedema
focal neurological signs

Question 13

What are the investigations for raised ICP in children?

Answer 13

USS babies/infants

CT in older children

Question 14

What are the investigations for raised ICP in adults?

Answer 14

CT

MRI better detail

Question 15

What is the treatment of raised ICP?

Answer 15

Surgical: treat the cause- remove the tumour, resolve haematoma

nonsurgical: steroids, mannitol, sedation, controlled ventilation (+decompressive craniectomy)

Question 16

Which features of raised ICP would be most concerning in relation to blood pressure, heart rate, and wide/narrow pulse?

Answer 16

bradycardia
irregular breathing
wide pulse pressure

Cushing’s triad, compromised of widening pulse pressure, bradycardia and irregular breathing, is a late sign indicating impending brain herniation. Systolic hypertension occurs as a reflex to maintain cerebral perfusion pressure in the presence of raised intracranial pressure.