Traumatic brain Injury

Question 1

Define dysautonomia

Answer 1

Dysfunction of the ANS

High HR, BP, temp, rigidity
Poor neuro recovery

Decorticate posture - everything ext except elbows
Decerebrate posture - everything ext

Question 2

Describe the pathophysiology of injury to the brain

Answer 2

Traumatic (blunt force, penetrating, #)
Non traumatic (hypoxic, CVA, infection)

Extradural haematoma (assoc with #, craniotomy required)
Subdural haematoma (assoc with acceleration of deceleration. Acute, sub acute or chronic)
Subarachnoid haemorrhage (poor outcome, assoc with aneurysm, high risk vasospasm, hydrocephalus, sudden severe headache)
Intraventricular haemorrhage (bleed into ventricles, acute hydrocephalus as Clots prevent CSF drainage)
Contusion (frontal or temporal lobe, parenchyma like haemorrhage.)
Diffuse axonal injury (widespread damage shear and tensile forces, transmission disrupted, no focal lesion)

Question 3

Calculate and define CPP

Answer 3

Cerebral perfusion pressure

CPP= MABP - ICP
70-90mmHg normal

Question 4

Describe auto regulation of blood flow in the brain

Answer 4

Local chemoreceptors respond to changes in chemicals such as PaCO2 in the blood.

Local baroreceptors respond to changes in blood pressure.

Central regulation involves the cardiovascular and vasomotor centres in the medulla.

Question 5

Discuss the effects of brain injury on respiratory function

Answer 5

Injury of the frontal lobe - loss of accessory muscles of breathing = more work for diaphragm

Injury to respiratory centres - loss of autoregulation, poor response to increased WOB, changes to POB, resetting chemoreceptor levels

Question 6

Discuss the effects of abnormal respiratory function on the brain

Answer 6

Increased PaCO2 = drowsiness, headache, increased ICP (thus poorer perfusion), vasodilation

Decreased PaCO2 = decreased ICP, vasoconstriction, confusion

Question 7

What is the normal ICP?

Answer 7

7-15mmHg

Question 8

Calculate and define CBF?

Answer 8

Cerebral Blood Flow

CBF = CPP / CVR
CVR = resistance

Question 9

Discuss positive and detrimental effects of physiotherapy on brain and lung function (TBI)

Answer 9

Prevent secondary brain injury

MHI decreases CO2 - vasoconstriction and decreased ICP, counteracts other therapy ICP increases.
Manual therapy - secretion clearance
Suction - C/I facial injury, CSF Leak, increased ICP and MABP
Multimodal - fabulous. Increases ICP but CPP okay due to increased MABP.
Exercise - prevents ICU acquired weakness, doesn’t increase ICP
Sitting - reduces ICP

Question 10

What techniques can be used with patients with TBI?

Answer 10

Positioning
MHI
Percussion, vibes, shaking
Suction
Multimodal physio
Sitting/standing
Exercise
MV

Question 11

Suggest modifications to treatment to minimize detrimental effects on TBI patients

Answer 11

Use MHI as a vasoconstriction technique prior to using techniques that will vasodilate

Modify posture to sitting to decrease ICP if required