Summary N243 Spinal Cord Injury

SEE CHARTS BELOW Nervous System Review • Ascending Tracts (Sensory) o Carry sensory information from receptors in the skin, muscle, joints, viscera, and blood vessels to higher levels of the CNS • Descending Tracts (Motor) o Carry signals that are responsible for voluntary muscle movement o Upper motor neurons (UMN) ▪ Begin in the cerebral cortex and project downward o Lower motor neurons (LMN) ▪ Influence skeletal muscles of the arms, trunk, and legs; are located in the anterior horn Spinal Cord Injury (SCI) • Definition: A complete or partial damage to the Etiology • Predominant risk factors include young age, male gender, and alcohol/ drug use Pathophysiology: Categories of Injury • Primary Injury: refers to initial mechanical disruption of the axons as a result of stretch or laceration leading to tearing or transection of the spinal cord o Cord compression: bone displacement causes trauma o Penetrating trauma ▪ GSW ▪ Stab wounds o Traction o Spinal Stroke • Neurogenic Shock: result of loss of ANS function below level of injury o Hypotension and bradycardia with warm extremities o Loss of sympathetic nervous system innervation (thoracic and lumbar) o Venous pooling and peripheral vasodilation o Patient does not perspire in in affected portions o Associated with cervical or high thoracic injuries; T6 or higher ▪ High risk for patients who suffer T6 of higher injury; innervation of ANS at this level o Vasopressors given as treatment Classification of Injury • Degree of Injury o Complete: loss of both sensory and voluntary motor communication from brain to periphery ▪ Results in paraplegia or tetraplegia o Incomplete: ability of spinal cord to relay messages to and from the brain is not completely absent • L tact spinal cord that causes permanent changes in sensation and loss of voluntary control below the site of injury • 30% of people with SCI are re-hospitalized one or more times during any given year following injury Tetraplegia/ Quadriplegia o Diseases • Secondary Injury: ongoing progressive damage after initial injury; extent of injury is a direct result of primary and secondary damages o Ischemia & Hypoxia o Microhemorrhage o Edema • Nursing focuses on prevention of secondary injury Types of Shock • Spinal Shock: sudden depression of reflex activity in the spinal cord below level of injury (50% of pts) o Occurs at the time of injury o All cord function below level of injury ceases o Last days to months o Hyporeflexia followed by hyperreflexia • Blue = sensory • Red = motor • Most sensory is posterior • Most motor is anterior • Anterior damage: Cannot move but sensation is intact • Posterior damage: Able to move, but loss of sensation • Brown-Sequard Syndrome (Lateral) • Cause: Transverse hemi- section of the cord (half of the cord is cut from north to south) as a result of knife or GSW injury • Characteristics: Ipsilateral paralysis, with ipsilateral loss of touch, pressure, and vibration; contralateral loss of pain and temperature Level of Injury Remaining Movement C1 to C3 Often fatal, vagus nerve domination of heart, respiratory, blood vessels and all other organs below injury Movement in neck and above, loss of innervation to diaphragm, absence of independent respiratory function C4 Vagus nerve domination of the heart, respirations, and all vessels and organs below injury Sensation and movement in neck and above, may be able to breath without a ventilator C5 Vagus nerve domination of the heart, respirations, and all vessels and organs below injury Full neck, partial shoulder, back, biceps; gross elbow, inability to roll over or use hands, decreased respiratory reserve C6 Shoulder and upper back Vagus nerve domination of the heart, respirations, and all vessels and organs below injury abduction and rotation at shoulder, full biceps to elbow flexion, wrist extension, weak grasp of thumb, decreased respiratory reserve (below level of injury) SCI: Incomplete Lesion • Central Cord Syndrome • Cause: injury or edema of the central cord, usually cervical area; may be caused by hyperextension injuries Characteristics: Motor deficits (in upper extremities), sensory loss more pronounced in upper extremities • Anterior Cord Syndrome • Cause: acute disc herniation or hyperflexion injury; also may be result of anterior spinal artery injury • Characteristics: Loss of pain temperature, and motor function below level of injury o Light touch, position And vibration Sensation remains intact • Posterior Cord Syndrome • Cause: Hyperflexive neck injury, occlusion of spinal artery, tumors, disc compression, syphilis, MS, and vitamin B12 deficiency • Characteristics: Loss of proprioception and vibration senses, ataxia, hypotonia, hyporeflexia of deep tendon reflexes Clinical Manifestations & Interventions • Depend on the extent of the injury to the spinal cord • A complete SCI has loss of both sensory and voluntary motor fibers • Incomplete SCI denotes sensory and/or motor fibers are preserved below the lesion • Cardiovascular Manifestation o Injury above T6 decreases influence of the sympathetic nervous system ▪ Bradycardia ▪ Peripheral vasodilation ▪ Relative hypovolemia o Cardiac Monitoring ▪ If HR 40, Atropine is given o Peripheral Vasodilation ▪ IV fluids or vasopressors to increase BP if fluids ineffective o DVT/ PE prophylaxis o Older Adult ▪ CV disease, heart rate lower C7 to C8 Vagus nerve domination of the heart, respirations, and all vessels and organs below injury All triceps to elbow extension, finger extensors and flexors, good grasp with some decreased strength, decreased respiratory reserve Paraplegia • Diaphragm innervated at C3, C4 and C5 o Diaphragm may function w/ injury to C4, C5 • Respiratory Manifestation o Above C4 ▪ Total loss of respiratory function; vent