lesson 7 b

Lesson 7BDisability — Part TwoCentral Nervous System

Trauma:Injuries to the Spinal Cord

Spinal Trauma (1 of 2)

• In the United States, 15,000 to 20,000 spinal injuries occur annually

• It is most common in ages 16 to 35 years• 80% of cases occur in males

Spinal Trauma (2 of 2)

• Causes include:– MVCs: 48%– Falls: 21%– Penetrating injuries: 15%– Sports injuries: 14%– Other: 2%

• Improper assessment and management can result in permanent paralysis

Anatomy: Spinal Column(1 of 2)

• Cervical (7 vertebrae)• Thoracic (12 vertebrae)• Lumbar (5 vertebrae)• Sacrum (5 vertebrae)• Coccyx (4 vertebrae)

Anatomy: Spinal Column(2 of 2)

Anatomy: Spinal Cord(1 of 2)

• The spinal cord fills the spinal canal– Leaves little room for swelling, hemorrhage,

or bone injury • Contains motor and sensory tracts• The tracts form nerves that go to

specific areas of the body– Sensory– Motor

Anatomy: Spinal Cord(2 of 2)

Anatomy: Spinal CordDermatomes and Sensation (1 of 2)

• Sensory levels– Spinal cord

• Nerves exit each vertebral level and detect sensation in specific areas of the body

• Area that each nerve senses is called a “dermatome”

• This creates a sensory map

Anatomy: Spinal CordDermatomes and Sensation (2 of 2)

Pathophysiology of CNS Injury

• Primary injury– Damage that occurs at the moment of impact

• Secondary injury– Damage that occurs subsequent to the initial

impact• Systemic causes• Intrinsic causes

– Prehospital management can often prevent or minimize the effects of secondary injury

Pathophysiology of CNS Injury: Secondary Injury

• Systemic causes– Hypoxia– Hypotension– Anemia (blood loss)– Increased or

decreased CO2

– Increased or decreased blood glucose

• Intrinsic causes– Increased

intracranial pressure (ICP)

– Edema– Hematomas– Seizures

Patient Assessment:Primary Assessment

• Determine the mechanism of injury and the need to consider possible spine injury

• Is there: – Airway compromise?– Ventilatory compromise?– Adequate oxygenation?– Adequate circulation and perfusion?

Patient Assessment

• Neurologic assessment for disability– The complete neurologic exam consists of six

components:• Mental status (MS)*• Cranial nerves*• Motor function*• Sensory function*• Coordination• Reflexes

*In most cases only the first four are completed in the prehospital setting

Patient Assessment: MentalStatus (1 of 3)

• A-V-P-U• Provides an initial impression

– Alert– Responds to Verbal stimulus– Responds to Painful stimulus– Unresponsive

• Glasgow Coma Scale – Use the modified GCS for pediatrics

• The GCS should be scored after the correctible causes of altered mental status have been addressed


Patient Assessment

• Assessing for symmetry of function (movement and sensation) is key– Asymmetry is abnormal until proven otherwise– In some people, asymmetry is a normal or

baseline finding• Always ask, “Is this normal for you?”

Patient Assessment: MotorFunction

• Test upper extremities by having the patient:– Move the hands and arms– Squeeze your fingers

• Test lower extremities by asking the patient to:– Wiggle the toes– Push and pull the feet against resistance

Patient Assessment: SensoryFunction (1 of 3)

• For a patient who is conscious with a suspected spinal cord injury (SCI):– Assess dermatomes to estimate the level of

spine injury– Start at the head and work down to find the

level of loss of sensation

• If loss of sensation is at:– Clavicles: C4–C5 injury– Nipples: T4 injury– Umbilicus: T10 injury– Pelvic rim: T12 injury


• In an unconscious patient, assess for sensation with deep pain response– Sternal rub– Nailbed compression

• Reflex response (from best to worst)– Purposeful withdrawal from pain– Nonpurposeful movement to pain– Flexion (decorticate posturing)– Extension (decerebrate posturing)– No response


Spinal Injury (1 of 2)

• Trauma to the spine may result in:– Spinal column fracture– Spinal cord injury

• Complete transection• Incomplete syndromes

– Brown–Séquard– Anterior cord– Central cord

– Both

Spinal Injury (2 of 2)

Anterior cord syndrome Central cord syndrome

Brown-Séquard syndrome

Spinal Cord Injury: ClinicalFindings (1 of 3)

• Motor– Muscle weakness– Muscle paralysis

• Sensory– Pain– Paresthesia (numbness)– Total loss of sensation

• The extent and location of sensory and motor loss depend on the location and level of the injury

• High cervical injuries– Paralysis of diaphragm and intercostal

muscles results in total loss of ability to breathe

• Lower cervical injuries– Diaphragm still functions– Paralysis of intercostal muscles only


• Cervical or high thoracic spinal cord injury may result in hypotension– Disruption of sympathetic nervous system results

in unopposed parasympathetic tone• Vasodilation• Bradycardia• Warm, dry skin

• However, the most likely cause of shock in any trauma patient is hemorrhage, which must be ruled out before calling it neurogenic “shock”


CNS Injury Management

• The overall goal is to prevent or recognize and treat secondary spinal cord injuries– Hypoxia– Hypotension– Hemorrhage

• Spinal fractures, in most cases, can only be diagnosed and managed at the receiving hospital

CNS Injury Management:Overview

• Prehospital setting– A-B-C-D-E approach– Spinal motion restriction– Initial resuscitation– Transport and destination decisions

CNS Injury Management:Airway (1 of 2)

• Open it– Maintain spinal motion restriction (as

appropriate for the mechanism of injury)– Jaw thrust

• Clear it– Use suction as needed

• Maintain it– GCS of 9 or more? – Able to maintain patency?

• Consider airway management as necessary

• If active airway management is required, monitor:– Oxygen saturation (95% or higher)– BP – End-tidal carbon dioxide (ETCO2)

• Confirm proper tube placement– Use two methods:

• Physiologic• Mechanical

CNS Injury Management:Airway (2 of 2)

CNS Injury Management:Breathing

• Provide oxygen (100%)– A single episode of hypoxia, O2 saturation

< 90%, worsens outcome in patients with TBI• Assist ventilations (as needed)

– Maintain normal ETCO2 at 35 to 40 mm Hg– Ventilation rates

• Adults: 10 to 12 breaths per min• Pediatric: 12 to 20 breaths per min

– No routine hyperventilation

CNS Injury Management:Circulation (1 of 2)

• Control hemorrhage and prevent anemia:EVERY RBC COUNTS!

• Maintain adequate BP and perfusion

• If BP is normal or elevated:– IV of LR/NS TKO

• If BP is decreased:– IV of LR/NS bolus, with fluid titrated to

maintain BP of 90 to 100 mm Hg • A single episode of hypotension,

BP < 90 mm Hg, worsens outcome in patients with CNS injury

CNS Injury Management:Circulation (2 of 2)

Spinal ImmobilizationAlgorithm: Blunt Trauma (1 of 5)

• Concerning mechanism of injury:– Violent impact to the head, neck, torso, or

pelvis– Sudden acceleration, deceleration, or lateral

bending forces to neck or torso– Falls– Ejection or fall from any motorized or human-

powered transport device– Shallow-water diving incident


• Distracting injuries– Any injury that may impair the patient’s ability

to appreciate other injuries, including: • Long-bone fracture• Suspected visceral injury• Large laceration, degloving, or crush injury• Large burns• Any other injury that produces acute functional

impairment


• Inability to communicate– Speech or hearing impaired– Speaks a foreign language– Small children


Spinal Immobilization Algorithm:Penetrating Trauma (1 of 2)

• Unstable spinal fractures from penetrating trauma are extremely rare

• Life-threatening conditions take priority

Spinal Immobilization Algorithm:Penetrating Trauma (2 of 2)

CNS Injury Management:Spinal Cord

• Prevent secondary injury– Maintain adequate oxygenation– Maintain adequate perfusion (BP)

• Steroids for spinal cord injury– No longer recommended

CNS Injury Management

• Transport and destination– Minimal on-scene time– Supine position– Appropriate receiving facility– Frequent reassessment

Expose

• Component of the primary assessment• Allows visualization of all body areas and

identification of hidden injuries• Remove clothing only as appropriate

– Driven by MOI/kinematics and patient complaints

– If suspected criminal activity, consider evidence preservation

– Maintain patient privacy• Prevent body heat loss

Summary (1 of 2)

• Identify the mechanism of injury• Perform primary assessment

– Identify and treat life-threatening conditions first

• Key determination is if initial findings are changing and in which direction (better or worse)

• Neurogenic “shock” may occur in patients with spinal cord injury– Hemorrhagic shock is still the most common

cause of shock overall and must be ruled out

• Evaluate need for spinal immobilization– When in doubt, immobilize

• Treatment key: minimize secondary injury of the spinal cord– Correct or prevent hypoxemia– Correct or prevent hypotension

• Transport to an appropriate facility

Summary (2 of 2)

Questions?

lesson 7 b

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