Spinal Cord Injury

Yowch My Back :(

Spinal Cord

• Extends from _________ to ____

• _____ pairs of spinal nerves

• Diameter?

• Ending components?

• Extends from foramen magnum to L2

• 31 pairs of spinal nerves

• Diameter?

  • Cervical enlargement → Supplies upper limbs

  • Lumbar Enlargement → Supplies lower limbs

• Ending components?

  • Conus medullaris → Ending, tapered. Between L1 and L2

  • Cauda Equina → Origin of spinal nerves from conus medullaris

What portion of the spinal cord supplies the upper limbs?

Cervical enlargement

What portion of the spinal cord supplies the lower limbs?

Lumbar enlargement

Conus Medullaris

• Inferior ending of spinal cord

• Ends between L1 and L2

Cauda Equina

• Origin of inferior spinal cords

• Extends from conus medullaris

Membrane layers of the meninges

• Dura meter → Strong, outer layer

• Arachnoid mater → Thin, non-vascular

• Pia mater → Inner layer, tightly bound to spinal cord

Dura mater

• Layer of meninges

• Strong and tough

• Outer layer, continuous

Arachnoid mater

• Layer of meninges - Middle

• Thin, non-vascular

Pia mater

• Layer of meninges

• Inner layer

• Tightly bound to spinal cord

Epidural space

• OUTSIDE of dura mater

• Anesthetics injected here

• Fat-filled for padding

Subdural space

• Between dura and arachnoid

• Filled with serous fluid

Subarachnoid space

• Between Pia and arachnoid

• Filled with CSF

• Spinal anesthesia is injected here

Grey matter

• neuron cell bodies, dendrites, and axons

• Divided into horns

  • Posterior

  • Anterior

  • Lateral

White matter

• Myelinated axons

• 3 columns

  • Ventral

  • Dorsal

  • Lateral

Posterior horn of spinal cord

• Sensory roots and ganglia

• “Dorsal half”

Anterior horn of spinal cord

• Motor roots

• “Ventral half”

True or false:

Spinal cord injuries and their associated changes are always permanent

FALSE

• Can be temporary or permanent

• Only type of 100% permanent spinal cord injury → SEVERED

Leading cause of traumatic spinal cord injuries

Motor vehicle crashes

Primary spinal cord injury

• Initial physical trauma

• Unlikely for the severity of it to be changed by surgery or any other interventions

Examples:

• Spinal cord compression

• Penetrating trauma

Secondary Spinal Cord Injury

• Ongoing and progressive damage - Occurs after and as a result of initial injury

• Can be prevented/altered with nursing care!!!

• Occurs minutes to hours after initial injury

  • Edema → Cord compression → Ischemic damage → Neuron destruction

• Glial scar

Glial scar

• Secondary spinal cord injury

• From inflammatory response

• Physical barrier to nerve communication → Irreversible nerve damage

Spinal cord injuries are classified by…

• Mechanism of injury

• Level of injury

• Degree of injury

Major mechanisms of spinal cord injury

• Flexion

• Flexion-Rotation

• Hyperextension

• Rotation

• Vertical compression

What mechanism of spinal cord injury is the most unstable?

Flexion-rotation

Can lead to severe neuro deficits

Flexion Spinal Cord Injury

• Compression of vertebral bodies

Levels of spinal cord injury

• Skeletal → Where the most damage to vertebra and ligaments is

• Neurological → Damage to the cord itself

  • Determine the lowest segment of cord with normal function

Skeletal vs Neurological level of injury

• Skeletal

  • Where the vertebra, ligaments, and supporting structures have the most damage

• Neurological

  • The lowest segment on the spinal cord that has normal functioning

  • Everything below that level is impacted by the injury

How to determine the neurological level of injury

• Test sensory and motor function on both sides

True or false

The skeletal and neurological level of injury are not always the same

True

A spinal cord injury between C1 and T1 results in…

Tetraplegia

• Involvement of all 4 extremities

• Arms may be completely or partially paralyzed/involved, but lower injury is generally better

A spinal cord injury below T2 results in…

Paraplegia

• Lower extremities affected\

• Potential for total independence 🙂

A spinal cord injury between ___ and ___ results in tetraplegia

C1 and T1A

A spinal cord injury below ___ results in paraplegia

T2

Are most spinal cord injuries generally complete or incomplete?

Incomplete!

What type of bony injury results in a singular break of spinous or transverse processes, and alignment of spinal cord generally remains intact?

• Simple fracture

• May cause later spinal column instability!!!

What bony injury occurs when one vertebrae overrides another?

• Dislocation

• May have unilateral or bilateral facet dislocation

Incomplete vs Complete cord involvement

Incomplete → More common, mixed loss of function/activity

Anterior cord syndrome

• Injury details?

• Impaired functions?

• Intact functions?

• Flexion injury w/ anterior cord compression

• Damage to anterior spinal artery → Compromises blood flow to cord

• Impaired functions:

  • Motor paralysis

  • Loss of pain and temperature sensation below level of injury

• Intact functions:

  • Touch, position, vibration, and motion sensations

Central cord syndrome

• Damage to _____ cord

• Most commonly occurs in the _____ region

• More common in what population?

• Upper extremities?

• Lower extremities?

• Damage to central cord

• Most commonly occurs in the cervical region

  • Neck hyperextension

• More common in older adults w/ degenerative disease

• Motor weakness + altered sensation in upper extremities

• Lower extremities usually not affected

Brown-Sequard Syndrome

• Rare

• Damage to half the cord

• Usually caused by penetrating injury

• Same side of body as injury

  • Loss of motor function, light touch, pressure, position, vibration sense

• Opposite side of body as injury

  • Loss of pain, temperature sensation

What rare incomplete spinal cord injury is often caused by penetrating injuries?

Brown sequard syndrome

What is useful for determining where the spinal cord injury occurred and is used when testing sensory function?

Dermatomes → Dividing and assigning body areas to vertebral levels

Classification of SCI severity

• Testing motor and sensory function

• Sensory

  • Light touch/pinprick along dermatomes

• Strength grading of muscles on both sides + motor function

• Categories

  • A = Most severe

  • E = Least severe

Emergency management of a spinal cord injury

ABCs!!

• Ensure patent airway + respirations

• Cervical injury → No head-tilt or chin lift

• Keep SaO2 > 90% → Administer O2

• Stabilize the cervical spine → Prevent further damage

Other things → Assess for other injuries, obtain imaging

Immobilization of spine

• Maintain ______ position

  • Keep patient ______

• Materials:

• Turning → _______

  • Use ______________ if needed

• Spinal immobilization should not interfere with __________

• Maintain neutral position

• Materials:

  • Rigid cervical collar

  • Backboard with straps

• Keep patient supine

• Turning → Log-roll

  • Use reverse trendelenburg if needed

• Spinal immobilization should not interfere with resuscitation

If a patient has a suspected spinal cord injury, what should we also suspect?

Head injuryyy

What characteristics make a SCI patient a possible early surgery candidate?

• Cord compression

• Open/Compound fracture

• Penetrating wounds

• Bony fragments in cord

• Progressive neurologic deficit

Purpose of skeletal traction

• NOT long term!

• Keep cervical spine in alignment until a permanent solution is developed

• Spinal reduction/decompression

True or false:

Gardner-Wells tongs require pin site care due to a risk for potential infection

FALSE

• Typically short term

• No pins!

Skeletal traction

• Short term - No pins!

• Usage of weights (10 pounds, then 40-70 lbs)

• Spinal decompression/reduction

• Crutchfield or Gardner-Wells tongs

Halo Vest

• Used for immobilization with spinal fractures

• Allows movement and ambulation while bones fuse

• Pin Site Care

Contraindications of halo vest

• Ligament instability

• Morbid obesity

• Older age

• Cachexia

• Non-compliance

Pin site care for Halo Vest

Risk for infection!!!

• Chlorohexidine swabs twice a day

• Antibiotic ointment

What immobilization method is used for stable thoracic or lumbar spine injuries?

“Body Jacket”

• Thoracolumbar sacral orthosis TLSO

• Limits spinal flexion, extension, and rotation

• Requires meticulous skin care!!!

What immobilization method is used for unstable thoracic or lumbar spine injuries?

Surgery → Decompression and fusion +

• TLSO (body jacket)

• Lumbosacral orthosis LSO

Spinal cord injuries above ___ and ____ result in the requirement for mechanical ventilation

C3 and C4

How do spinal cord injuries above C3 and C4 impact respiratory ability?

• Unable to breathe independently/spontaneously

• Mechanical ventilation ☹

How do spinal cord injuries below C4 impact respiratory function?

• Diaphragmatic breathing (if phrenic nerve is functional)

• Loss of intercostal and abdominal muscles → Hypoventilation

• Intubation might be needed

• Other interventions

  • Monitor for labored breathing, poor cough, or exhaustion

  • Administer O2

  • Chest physiotherapy to clear secretions

Respiratory assessment of spinal cord injury patients

• Breath sounds

• ABGs

  • Uncomplicated = PaO2 >60, PaCO2<45

• Skin color (pallor, cyanosis)

• Breathing patterns

• Sputum

• Ability to count to 20 without taking a breath

What are cardiovascular effects that may occur as a result of spinal cord injury?

• Unopposed vagal response

  • Vagal stimulation may lead to

    • Bradycardia

    • Risk for cardiac arrest

• Loss of SNS in Peripheral vessles

  • Chronic hypotension

  • Orthostatic hypotension

  • Risk for VTE

Possible impacts on the cardiovascular system in spinal cord injuries?

a. Bradycardia

b. Chronic hypertension

c. Stroke

d. Cardiac arrest

A, C, and D

• Unopposed vagal response → Bradycardia and cardiac arrest

• Loss of SNS in peripheral vessels → Chronic hypotension, orthostatic hypotension, and VTE risk

Why might a patient with a spinal cord injury be at risk for bradycardia and cardiac arrest?

• Unopposed vagal response

• Avoid vagal stimulation

Why might spinal cord injury patients be at risk for chronic hypotension or venous thromboembolism?

• Loss of Sympathetic nervous system control in peripheral vessels

If a patient has symptomatic bradycardia, what is the expected treatment?

Atropine and/or pacemaker

In spinal cord injury patients, systolic BP should be kept _____ and MAP should be ______

In spinal cord injury patients, systolic BP should be kept above 90 and MAP should be between 85-90

A spinal cord injury at __ and above results in orthostatic hypotension in patients.

A spinal cord injury at T6 and above results in orthostatic hypotension in patients.

A spinal cord injury at T6 and above results in _________ in patients.

A spinal cord injury at T6 and above results in orthostatic hypotension in patients.

If a SCI patient has symptomatic orthostatic hypotension, what are important nursing interventions?

• Abdominal binder

• Graduated compression stockings

• Midodrine → Venous return

What medication is suggested for orthostatic hypotension?

Midodrine

VTE prophylaxis

• Low-molecular-weight heparin or low-dose heparin

• SCDs and/or graduated compression stockings

• Assess thighs and calves every shift

• ROM exercises + stretching

Urinary retention and SCI

• Immediately following injury

• Neurogenic Bladder → Loss of autonomic + reflex control of bladder and sphincter

Acute → Indwelling catheter

Long-term → Intermittent catheterization

True or false:

For long-term management of neurogenic bladder, indwelling catheters are used.

FALSE

Acute phase → Indwelling catheter

Long-term → Intermittent catheterization

• Chronic catheter increases infxn risk

SCI and GI system:

• T5 → _____________

• T12 → _____________

• T5 → GI hypomotility

  • Paralytic ileus

  • Gastric distension

• T12 → Neurogenic bowel

  • Loss of sphincter control/reflexes

SCI and GI system

__ → GI hypomotility

__ → Neurogenic bowel

• T5 → GI hypomotility

  • Paralytic ileus

  • Gastric distension

• T12 → Neurogenic bowel

  • Loss of sphincter control/reflexes

When a T5 injury impacts GI function…

• What are complications?

• Nursing management?

• Results in GI hypomotility

• Can cause paralytic ileus and gastric distension

Interventions:

• NG tube, intermittent suction

• PPI or H2 receptor blockers (omeprazole, famotidine)

T12 injury and GI function

• Neurogenic bowel → Loss of voluntary control

  • Can also occur during spinal shock

• Bowel is areflexic

• Decreased sphincter tone

Interventions:

• When reflexes return → BOWEL PROGRAM

• Aids in sphincter toning, and reflex emptying

When is bowel program initiated?

• Neurogenic bowel

  • Following spinal shock

  • SCI at T12 or below

• When reflexes return!

Decreased thermoregulation is more common in patients with…

High cervical injury

Decreased thermoregulation

• More common w/ high cervical injuries

• Decreased ability to sweat or shiver below the level of injury

• Don’t over cool or overheat the patient!

Neurogenic Shock

• T6 or higher SCI

• Loss of SNS tone → Unopposed PNS response

• Distributive shock!!!!

  • Peripheral vasodilation

    • Reduced venous return, pooling of blood in veins, loss of pressure

  • Hypotension

    • Decreased cardiac output

  • Bradycardia

    • From loss of sympathetic tone/muscle contractility

• Fluid infusions may not help

• Vasopressors may be indicated

  • Norepi, phenylephrine, dopamine

Spinal shock

• ½ of all SCI pts

• Immediate loss of function below level of injruy

  • Loss of Deep tendon/sphincter reflexes

  • Loss of sensation

  • Flaccid paralysis (including bowel/bladder)

• Lasts 1-6 weeks post injury (normally, can be faster)

After spinal shock

• Lasts days to weeks, usually 1-6 weeks post injury

• Spinal neurons gradually regain excitability → Ending of spinal shock

• May mask post-injury neurologic function

  • We won’t know their true ability/severity until spinal shock ends

  • Don’t know if it will be permanent!

Autonomic dysreflexia

• T6 or above

• Occurs following spinal shock

• Returning reflexes → Get out of wack!

  • SNS excitement/overactivation, PNS can’t respond

• MEDICAL EMERGENCY!

How is autonomic dysreflexia often caused?

• Identification and elimination of inciting stimulus can lead to resolution

• Usually caused by distended bladder, rectum, tight clothing/shoes

How does autonomic dysreflexia occur?

• strong sensory input below injury

• SNS below level of injury responds with arteriolar vasoconstriction and increased BP

• PNS unable to fully counteract, but may lead to bradycardia

Manifestations of Autonomic Dysreflexia

• Hypertension

  • 20-40 above systolic baseline, but may reach up to 300

• Nasal congestion

• Bradycardia

  • PNS is trying to respond to HTN

• If these are reported, check BP!!!

  • Throbbing headache

  • Spots/Blurred visual field

  • Anxiety and nausea

• Piloerection (goose bumps) BELOW level of injury

• Diaphoresis and Skin flushing ABOVE level of injury

Treatment of Autonomic Dysreflexia

• FIRST: Elevate head of bed 45 degrees or high-fowlers

• Search for cause

  • Immediate catheterization → Bladder distension

    • Check indwelling

  • Remove skin stimuli → Tight clothes/shoes

  • Rectal exam after applying anesthetics → Stool impaction

• Notify provider

• Antihypertensive meds

  • NTG, nitroprusside, hydralazine

What treatment may decrease or eliminate ventilator requirements in patients with high SCI?

Implanted phrenic nerve stimulator

Electronic diaphragmatic pacemakers

What treatment may decrease or eliminate ventilator requirements in patients with low level SCI?

Respiratory muscle training

Abdominal binders

Overall → Improving performance of respiratory muscles