33305 Lecture 7 - CNS injury - Brain and Spinal Cord

Learning Outcome 1

Describe the pathophysiology and clinical features of traumatic brain injury (TBI) and spinal cord injury (SCI)

Definition of a traumatic brain injury and examples :

TBI = injury to the scalp, skull, or brain caused by external force/trauma.

Examples:

• Falls

• MVAs

• Assault

• Sports injuries

Types of TBI???

Closed Head Injury

• Brain injured without skull penetration - e.g concussion after hitting head in sport

Open Head Injury

• Skull/dura penetrated

• Higher infection risk

• More severe damage

E.g gunshot wound

Primary vs Secondary Brain Injury

Primary injury?

Damage occurring at impact:

• Contusions (bruising)

• Lacerations

• Blood vessel damage

• CANNOT usually be reversed

Primary vs Secondary Brain Injury

Secondary injury?

Occurs after trauma due to:

• Cerebral oedema

• Ischaemia

• Chemical changes

• Increased ICP

CAN worsen brain injury overtime but CAN be reduced with treatment

Grading of TBI?

Mild - Moderate - Severe

Mild

• GCS 13–15

• Brief LOC

• Nausea/confusion

• Headache

Moderate

• GCS 9–12. - more significant neurological impairment

Severe

• GCS <8

• Severe brain dysfunction

• Airway/intubation often needed

What does increased ICP do and what can it lead to?

• bleeding/swelling ↑ intracranial volume

• skull cannot expand

• ICP rises

• ALL OF THIS LOWERS blood flow/oxygen to the brain

Can lead to:

• brain cell death

• herniation

• LOC

Brain Herniation? Raised ICP pushes brain tissue into areas it should not go.

Raised ICP pushes brain tissue into areas it should not go.

Dangerous because it compresses:

• brainstem - controls basic life functions

• breathing centres - control breathing

• circulation centres - control hr and bp

Can cause:

• respiratory arrest

  • death

Monro-Kellie Doctrine

The skull contains:

• brain tissue

• blood

• CSF

Because the skull is rigid:

• if one increases (e.g. bleeding/swelling)

• another must decrease

Otherwise ICP rises.

Example:

• cerebral oedema after TBI increases pressure because there is no room for expansion.

Clinical Manifestations of TBI

• headache

• vomiting

• confusion

• ↓ LOC

• unequal pupils

• weakness

• seizures

• behavioural changes

These occur because the injured/swollen brain cannot function normally.

Causes of SCI?

• falls

• MVAs

• diving/sport injuries

• trauma

Manifestations of SCI

Depend on injury level.

Possible findings:

• paralysis

• loss of sensation

• bladder/bowel dysfunction

• respiratory compromise

Upper body injuries = more respiratory problems.

Why do manifestations of spinal cord injury (SCI) depend on the level of injury?

The spinal cord controls movement, sensation, bladder/bowel function, and breathing below the injury level. Higher spinal injuries affect more of the body and can impair breathing, while lower injuries mainly affect the legs and bladder/bowel function.

Neurogenic Shock

Loss of sympathetic nervous system control after SCI.

Causes:

• vasodilation

• slowed heart rate

Signs:

• hypotension

• bradycardia

• warm dry skin

Because blood vessels cannot constrict properly.

Spinal Shock

Temporary loss of:

• reflexes

• sensation

• motor function

below injury level.

Occurs immediately after SCI.

Learning Outcome 2

Discuss collaborative and nursing management of the individual with TBI or SCI

Priorities in TBI Management?

ABCDE Assessment

• Airway

• Breathing

• Circulation

• Disability

• Exposure

Used to identify life-threatening problems first.

Airway Management In TBI?

Priority because ↓ LOC can obstruct airway.

May require:

• oxygen

• intubation

• ventilation

Goal:

• prevent brain hypoxia.

ICP Management? Goal and interventions

Goal:

• reduce swelling

• maintain cerebral perfusion

Interventions:

• head elevated 30°

• neutral neck alignment

• minimise stimulation

• mannitol

• sedation

Head elevation helps venous drainage from the brain.

Neurological Monitoring?

Assess:

• GCS

• pupils

• LOC

• motor response

• vital signs

Frequent changes may indicate deterioration.

Signs of raised ICP

• headache

• vomiting

• ↓ LOC

• unequal pupils

Cushing’s Triad??/

Late sign of raised ICP:

• bradycardia

• hypertension

• irregular respirations

Indicates brainstem compression.

SCI Management???

Spinal Precautions

• cervical collar

• spinal alignment

• log rolling

Prevents further spinal damage.

Respiratory Management in SCI?

Upper SCI can weaken respiratory muscles.

Monitor:

• RR

• oxygenation

• breathing effort

Preventing complications in SCI - What to do?

Pressure Injury Prevention

SCI patients may not feel pressure areas.

Interventions:

• repositioning

• pressure mattresses

• skin checks

DVT Prevention In SCI patients?

Immobility ↑ clot risk.

Use:

• compression devices

• anticoagulants

• mobilisation if possible

Interdisciplinary team consists of?

• nurses

• neurosurgeons

• physiotherapists

• OT

• speech therapy

• social workers

Learning Outcome 3

Use the nursing process as a framework to care for the patient with TBI or SCI

Assessments???

Neurological Assessment

• GCS

• pupils

• LOC

• motor/sensory function

Used to detect deterioration early.

Respiratory Assessment

• RR

• oxygenation

• airway patency

Especially important in high SCI/TBI.

Nursing diagnosis? Possible problems?

• ineffective cerebral tissue perfusion

• impaired mobility

• impaired gas exchange

• risk for aspiration

• risk for pressure injury

Planning/goals? Goals….?

• maintain airway

• maintain cerebral perfusion

• prevent complications

• maximise safety/function

TBI Nursing interventions????

• frequent neuro obs

• seizure precautions

• reduce stimulation

• maintain oxygenation

Because deterioration can occur rapidly.

SCI nursing interventions????

SCI

• pressure care

• repositioning

• bowel/bladder management

• respiratory support

Because immobility causes complications.

• stable neuro status

• adequate oxygenation

• no complications

• improved mobility/function

A: To check if the patient is improving, staying stable, and not developing complications after TBI/SCI care.