Spinal Cord Injuries: Etiology and Pathophysiology

• Mobility is purposeful body movement that depends on the musculoskeletal and nervous systems, adequate oxygenation, perfusion, and cognition.

Spinal Cord Injuries

• Disruption of individual growth and development is a major issue related to spinal cord injuries
• Potential economic losses and high rehabilitation costs add further complications
• Young adult men between 16 and 30 are at the greatest risk for spinal cord injuries
• 78% of spinal cord patients are 19-year-old males

Etiology and Pathophysiology

• Motor vehicle crashes account for 50% of spinal cord injury causes
• Falls account for 24% of spinal cord injury causes
• Violence accounts for 11% of spinal cord injury causes
• Sport injuries account for 9% of spinal cord injury causes
• Miscellaneous causes account for 6% of spinal cord injury causes
• In large urban areas, gunshot wounds may surpass falls as a cause

Initial Injury

• The spinal cord is wrapped in tough layers of dura
• Direct trauma rarely tears or transects the spinal cord
• Spinal cord injury due to cord compression occurs through bone displacement
• Interruption of blood supply to the spinal cord may cause injury
• Traction resulting from pulling on the spinal cord may cause injury
• Penetrating trauma, like gunshot or stab wounds, can cause injury

Pathophysiology

• Most spinal cord injuries are caused by a sudden, traumatic force that distorts the vertebral column's normal structure
• Bruising or tearing of nerves can occur due to distortions of the vertebral column's normal structure
• Damage to blood vessels in gray matter can occur due to distortions of the vertebral column's normal structure
• Initial trauma events kill neurons, demyelinate axons, and trigger inflammation
• Reduction in blood flow decreases oxygen and nutrients, leading to neuron death, especially in gray matter
• Swelling and edema compress nerves
• Immune cells trapped in blood vessels leak into the spinal cord
• Inflammatory response, scavenge debris, and fight infection can follow spinal cord injuries
• The destruction of nerves and loss of motor and sensory function can occur

Mechanisms of Injury

• Hyperflexion injury in C5-6 can occur through sudden deceleration
• Hyperextension injuries involve backward and downward motion, stretching and distorting the spinal cord
• Axial loading involves vertical compression, such as falling from a height and landing on the feet or buttocks
• Penetrating injuries involve objects like bullets or knives penetrating the spinal cord

Primary and Secondary Injury

• Neurological damage occurs at the moment of impact during the primary injury
• Secondary injuries involve complex biochemical processes affecting cellular functions that can occur within minutes and last for days or weeks, this is a concern after the initial injury

Classification of Spinal Cord Injury

• The ASIA Impairment Scale can classify spinal cord injuries
• Disruption of normal spinal cord function is classified as Complete SCI or Incomplete SCI
• Complete SCI includes tetraplegia or paraplegia: Total loss of all sensory and motor function below the level of injury, diagnosis is determined by the loss of sensory function in the S4-S5 area, and it is usually irreversible
• Incomplete SCI includes partial loss of sensory and motor function below the level of injury, there may be the detection of some sensation but little or no ability to move, or one can have movement with little or no sensation: It has a better chance of recovery

Effects of Spinal Cord Injury Throughout the Body

• Tetraplegia, also called quadriplegia, is paralysis of the upper and lower limbs and trunk, usually associated with cervical injury, lacking total brain & SC communication, and motor & sensory function loss
• Paraplegia is paralysis of all or part of the trunk, legs, pelvic organs, and is usually associated with damage in thoracic or lumbar regions
• Incomplete tetraplegia is the most common neurologic category at discharge, followed by incomplete paraplegia, complete paraplegia, and complete tetraplegia
• Hemiplegia involves paralysis of one half of the body divided along the medial sagittal plane

Common SCI Symptoms

• Pain can be a common affect of SCI
• Bladder and bowel problems can be a common affect of SCI
• Respiratory problems involving complete thoracic or cervical injuries can be a common affect of SCI, the higher the injury, the greater the loss of respiratory muscle control
• Cardiovascular problems like blood pressure instability and arrhythmias can be a common affect of SCI
• Reproductive problems can be a common affect of SCI

Syndromes Associated with SCI

• Syndromes associated with incomplete SCI: Central cord syndrome, anterior cord syndrome, Brown-Sequard syndrome, and Conus medullaris syndrome
• Cauda equina syndrome is not a true SCI

Clinical Manifestations of SCI

• Trauma causes cord compression, ischemia, edema, and possible transection, with severity depending on the injury's level and degree
• An incomplete lesion may show a mixture of symptoms
• The higher the injury, the more serious it is, especially when the proximity is to the medulla and brainstem
• Movement and rehabilitation potentials may be better based on the specific injury locations

Brown-Séquard Syndrome

• Damage is to only 1 side of the cord
• Loss of voluntary motor movement occurs on the same side as the injury
• Loss of pain, temperature, and sensation occurs on the opposite side of the injury because pathways cross shortly after entering the spinal cord
• Vasomotor paralysis occurs on the same side (ipsilateral) as the lesion

Central Cord Syndrome

• Occurs when there is cervical hyperextension-hyperflexion injury and hematoma formation in central areas of the cervical cord
• Motor and sensory deficits in upper extremities, varying degrees of bowel and bladder dysfunction, paralysis, loss of fine control of arms and hands
• Sensory loss below the SCI site and bladder control loss may happen
• Damage can happen to the central spinal cord
• This is more common in older adults
• Causes, by trauma, damage to large nerve fibers carrying information from the cerebral cortex to the spinal cord

Anterior Cord

• The most common incomplete SCI
• Injury to the anterior gray horn cells (motor), spinothalamic tracts (pain), anterior spinothalamic tract (light touch), and corticospinal tracts (temperature)
• Loss of movement, fine sensation, motor function, pain, and temperature sensation below the level of injury
• Position sense and sensations of pressure and vibration remain intact below the level of injury
• Caused by flexion and acute herniation from trauma, compression injuries, or ischemia to motor and sensory pathways in the anterior part of the cord

Posterior Cord

• Associated with cervical hyperextension with damage to the posterior column
• Loss of position sense, pressure, and vibration below the level of injury can prevent ambulation
• Sensation of pain, temperature, and motor function remain intact
• Compression or damage to the posterior spinal artery can provoke it, and is rare
• It results in a loss of proprioception

Cauda Equina Syndrome

• Damage to the sacral nerve roots causes progressive neurological syndrome, causing flaccid paralysis of the lower limbs and an areflexic (flaccid) bladder and bowel
• Patients complain of low back/lumbar pain with potential bilateral lower extremity pain
• Decreased or poor anal sphincter tone
• Impaired bladder control resulting in recent onset of bladder retention

Etiology and Pathophysiology- SCI Initial Injury

• Ongoing damage can be caused by various theories
• Apoptosis (cell death) occurs
• Complete trauma can results in severe cord damage and autodestruction of the cord with petechial hemorrhages
• Hemorrhagic areas in the center of the spinal cord can cause damage
• It is critical to provide initial care and management of spinal cord injuries
• Resulting hypoxia can have great harm
• Lactate metabolites & ↑ vasoactive substances are noted in Norepinephrine, Serotonin, and Dopamine levels
• High levels of vasoactive substances cause vasospasms, and hypoxia can lead to subsequent necrosis
• The body has a minimal ability to adapt to vasospasms
• By ≤ 24 hours, permanent damage results in edema and it creates a lack of space for tissue expansion
• Compression of cord and extension of edema above and below injury increases ischemic damage
• Extent of neurologic damage caused by spinal cord injury results from primary injury, and secondary damage -which includes Ischemia, hypoxia, microhemorrhage, and edema
• Extent of injury and prognosis for recovery is most accurately determined at least 72 hours or more after injury

Pathophysiology of Spinal Cord Injuries

• Spinal shock occurs shortly after a traumatic injury to the spinal cord, especially in the cervical & upper thoracic spinal cord, with complete loss of all muscle tone and normal reflex activity below the level of the injury
• The complete loss of all muscle tone includes the loss of rectal tone
• One may appear completely flaccid without function below the injury level
• Neurogenic shock is injury to the descending sympathetic pathways in the spinal cord and from loss of vasomotor tone & sympathetic innervation to the heart
• Return of function is observed through bladder tone, hyperreflexia, and sacral reflexes, and flaccid paralysis is followed by spasticity and hypertonicity

Spinal Shock Syndrome

• It is characterized by a temporary neurologic syndrome
• Complete loss of all muscle tone & normal reflex activity occurs below the level of the injury, including loss of rectal tone, ↓ reflexes, loss of sensation, flaccid paralysis, loss of bladder one, and loss of deep tendon reflexes, urinary bladder tone, peristalsis, and piloerection

Neurogenic Shock

• Injuries to the descending sympathetic pathways in the spinal cord cause it
• It is observed with SCI at the level of T6 or higher**
• Loss of vasomotor tone & sympathetic innervation to the heart causes a decrease in SVR & BP
• A type of distributive shock is characterized by hypotension, bradycardia, and warm, dry skin which are important clinical cues of CV compromise
• Hypovolemia & hypovolemic shock occurs r/t relative loss
• Loss of sympathetic nervous system innervation causes peripheral vasodilation, venous pooling, and ↓ cardiac output r/t sympathetic blockade
• Often associated with a cervical or high thoracic injury
• Pts are watched carefully during positioning because they can have orthostatic hypotension
• There is a high risk for DVT: patients need to be on prophylaxis therapy, PROM, SCOD, and anticoagulant therapy
• Patient is Poikilothermic- dependent on environment for regulation, the body will adjusts to the ambient temperature

Level of Injury

• Injury is located in the cervical spine, this will affect the upper and lower limbs
• Injury is located in the thoracic, this will affect the torso and legs
• Injury is located in the lumbar, this will affect the lower extremities

Quadriplegia

• Injury from may be located between C1 to T1

Paraplegia

• Injury is located in the thoracolumbar region from T2 to L1
• Pts have full use of arms but need a wheelchair to get around

SCI Assessment After

• Airway is assessed, it is determined if the patient is able to breath on their own. You must check for airway clearance. Maintain the neck in a neutral position and ensure proper airway management
• Breathing is assessed, see Table 24-7 from page 483 for more information
• Circulation is assessed, one must check for tissue perfusion. Cardiac monitor due to a risk for a bradycardia
• Circulation is assessed, one must check for tissue perfusion. Cardiac monitor due to a risk for bradycardia, or dysrhythmias
• A complete neurological assessment is needed to assess the motor skills and all possible damage location
• The most common diagnostics procedure is a CT, tomography, myelography, and MRI
• A screening will be performed. 15% of all trauma patients will have a cervical spine injury. The primary spinal screen assessment is a CT. Head/Neck and spine stabilization is important in these patients. Pts are places under bed rest with a hard collar in place. Keep applying the proper treatment until the correct diagnosis

Immediate Postinjury Problems

• Maintaining a patent airway
• Providing adequate ventilation
• Maintaining an adequate circulating blood volume
• Preventing extension of cord damage (secondary damage)

Clinical Manifestations- Respiratory System

• Respiratory complications correlate with the level of the injury. 02 sat levels have to maintain higher then 93%.
• Cervical injuries above the level of C4 causes special problems as result of high total loss of respiratory muscle function. Pts will need the usage of a mechanical ventilator to keep them alive
• The table from pg483 has the effects the C-spine has on the ventilator function
• Cervical injures below a C4 level will still need diaphragmatic breathing if the right phrenic nerve is working. Cord Edema in the spinal may cause respiratory issues. As a result of reduce vital volume there might by an Hyopvetilation
• Cervical and throatic Injuries are likely to cause paralysis
• You can have a hard time doing proper cough, there is techniques that place manual pressure so there lungs can be freed. If the coughing method does not work there is and artifical airway to let you breath and chest physiotherapy
• Possible outcomes may be; Neurogenic pulmonary edema, Pulmonary edema as result of fluid overload

Clinical Manifestations- Cardiovascular System

• Any Injury to the chord above a T6 will decrease the SNS level. Bradycardia will occur
• Prephial vasodilation which will lead to hypotention
• Relative hypovolemia happens as result of volume in the venus capacity being larger
• Decrease the risk for blood to exit to the heart. Use IV drugs and Vaso' to help keep levels fine

Clinical Manifestations- Urinary System

• Pts are exposed to a urinary retentions. To drain the bladder an intermittent catherter should begin shortly once the pt is stablize
• Regular intervels are needed to maintain, and to maintaine bladder infection

Clinical Manifestations- Gastrointestinal System

• Pts are suseptible to an decreased volumentary nuorgenic control over bowel
• Bowel is Areflexic and the Sphincter tone will be smaller. As reflexes are enhanced one of the outcomes can be a bowel that is more relfiex
• The reflex enhanced means Spinchter tone is enhanced, and it might need to be maintained with a bowel program

Clinical Manifestations- Metabolic Needs

• Nusoguatric suctioning is not a thing anymore. Pts are tested for acidosis levels, electrolyte levels
• Loss of weight level of 10% is expected. Nutritonal diet are highly requested as well as skins breakdown is highly important

Clinical Manifestations- Integumentary System

• One outcome from reduced movement will result in skins breakdown. Pressure ulcers as well as the need to frequently asses labs

Clinical Manifestations- Thermoregulation

• Poikiwothermism is a outcome and it's importnat to test temp to test for it. It is importnatn to regualte it
• Asses if a pt is shivering and sweating as well as a possible sign that the regulation is lacking

Clinical Manifestations- Vascular Problems

• High chace for deep veins thrombosis to occur
• Check a Dupler and always asses for an measurement

Medical Management- SCI

• Doctors need to assess the current patients conditions as well has their preferences as well. The goal is to stablize.
• Pharmacological management such by methypredonisne
• One major consdieration with cerival injures are to what consdieratiosn their are with the halo's
• One to the consdieraiton is a thorasic injrues
• For thracic injrues

Collaborative Care

• The starting goal is to sustatin the patients life. and making sure not to damage the chord more
• At cervival levels the body needs to be maintained util the full extent of the damage
• Systemic and neurogenic shock has to be treated as well

Collaborative Care- Surgical tx

• Doctors need to assess and chose proper treatments for the damage. Reduce the chords 2 degree of injury
• There is sepcific protocls to dececompress what is necceesary

Nursing Management- SCI

• The focus is to prevent and to reduce and to rehab these types of patietns

Care/Drug Therapy

• Vassopressors and Dopamine is a go to treamtent
• It is to treat specific atuonomic dysfunctions by enhancing artierial pressure

Immobilization'

• You must asses and watch for any realignment or any site that might indicate a further injruy
• This happens with kinetc therapy, which help stabalize the skin

Respiratory Dysfunction

• When they see some spinal cjords spinal cord edema, then respaitory ditess
• If the injrues is 0 above C4, the pt might need ventilation by endotracheal or traechopstomy

Respiratory Dysfunction

• The list of the potentail potbalmes on the pt include arest and ahteletsic

Cardiovascular Instability

• Low < to 60 beates, the loss, this coud result if they are any vagal stiumation
• An antichiolnergnic such at Atrpien cna work.

Fluid and Nutritional Maintenace

• NG is important and it needs to insrted
• Pt also has and elertrly and has food it is given with the food
• And hgih calories

Bladder and Bowel Management

• Pt need to have regular and completes, Caths and assesments

Temperature Control

• You lose control below the level of what that you want. Monitor the pts temp
• Try to asses them regaurlly

Stress Ulcers

• As result the ulceration of high dose of the corticorestrids it's important to test it daily and asses it.

Sensory Deprivation

• Pts can be confused. It might a long time for them to cope with this level, and it's ok

Reflexes

• Pay to thim when they return.

Autonomic Dysreflexia

• This is high CV system. You need toasses it often, for safety reasons, to prevent them by injury
• Asseing it from the carotid or the change in the aorta. This is from above the injruy

Autonomic dysreflexia

• High threat for compilation with high level hypertension, sever facila fushing, and ehadchees and pt

Autonomic Dysreflexia- Actions

• Raise the patients bed. Call doctor if needed
• Immedated cathilnzatioh as well
• Teach youself about symptoms

Neurogenic Bladder

• A type of bladder that has dysfucntion.
• Can ahve issues and needs to be monired. and has to test high level of extremity
• Plan the proper for you by your doctor

Neurogenic Bowel

• Voluantry might get lost.

Neurogenic Skin

• The protection of the skin is importnat. Teach people about the consitons

Sexuality

• Have proper auroess and acceptance. Must habel hum,an knowdge and respect
• Asses the proper level that is needed to address it.

Grief and Depressen

• Sympathy is not helpful, be patient and encouraging help with treatment
• Involve in decision making and be an the proper process

Explore the causes and mechanisms of spinal cord injuries, focusing on the role of motor vehicle crashes, falls, violence, and sports injuries. Understand the demographics, economic impact, and developmental challenges associated with these injuries. Learn about the initial injury process, including the protective role of the dura.