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26 Cards in this Set
- Front
- Back
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Neurogenic shock, characterized by hypotension and bradycardia, occurs
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fter an acute spinal cord injury that disrupts sympathetic outflow, leaving unopposed vagal tone.1 The term neurogenic shock must be carefully differentiated from another that has a very different meaning—namely, spinal shock. Spinal shock refers to the temporary loss of spinal reflex activity that occurs below a total or near total spinal cord injury.2 These terms are not interchangeable.
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Neurogenic shock, characterized by hypotension and bradycardia, occurs
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fter an acute spinal cord injury that disrupts sympathetic outflow, leaving unopposed vagal tone.1 The term neurogenic shock must be carefully differentiated from another that has a very different meaning—namely, spinal shock. Spinal shock refers to the temporary loss of spinal reflex activity that occurs below a total or near total spinal cord injury.2 These terms are not interchangeable.
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For high-dose methylprednisolone therapy to be effective, it should be given
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within 8 h of injury
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Acute spinal cord injury is usually caused by blunt trauma; penetrating trauma causes only 10 to 15 percent of cases
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Acute spinal cord injury is usually caused by blunt trauma; penetrating trauma causes only 10 to 15 percent of cases
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Acute spinal cord injury is usually caused by blunt trauma; penetrating trauma causes only 10 to 15 percent of cases
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Acute spinal cord injury is usually caused by blunt trauma; penetrating trauma causes only 10 to 15 percent of cases
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Acute spinal cord injury is usually caused by blunt trauma; penetrating trauma causes only 10 to 15 percent of cases.1,3 The majority of penetrating wounds that produce acute spinal cord injury are caused by gunshot wounds, with a small minority caused by stab wounds.1 Of the blunt trauma causes,
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automobile accidents are the most frequent, followed by falls and sports.5,6 The cervical region is the most commonly injured, followed by the thoracolumbar junction, the thoracic region, and the lumbar segments.
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Acute spinal cord injury is usually caused by blunt trauma; penetrating trauma causes only 10 to 15 percent of cases.1,3 The majority of penetrating wounds that produce acute spinal cord injury are caused by gunshot wounds, with a small minority caused by stab wounds.1 Of the blunt trauma causes,
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automobile accidents are the most frequent, followed by falls and sports.5,6 The cervical region is the most commonly injured, followed by the thoracolumbar junction, the thoracic region, and the lumbar segments.
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The spinal column is composed of
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33 bony vertebrae with interspersed cartilaginous intervertebral disks
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. The typical vertebra consists of
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an anterior vertebral body and a posterior vertebral arch. These elements form the borders of the vertebral foramen, which contains and protects the spinal cord. The superior and inferior articular processes arising from most vertebrae allow the spine to be a strong yet flexible structure. The pedicles and laminae form the sides of the vertebral arch and are notched to allow for the passage of nerves and blood vessels.
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. The typical vertebra consists of
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an anterior vertebral body and a posterior vertebral arch. These elements form the borders of the vertebral foramen, which contains and protects the spinal cord. The superior and inferior articular processes arising from most vertebrae allow the spine to be a strong yet flexible structure. The pedicles and laminae form the sides of the vertebral arch and are notched to allow for the passage of nerves and blood vessels.
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In general, the white matter is the outer covering of the cord. It contains the nerve fibers running up and down the spinal cord in tracts. The gray matter is made up of nerve cells and is formed in the shape of an H when viewed on cross section
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In general, the white matter is the outer covering of the cord. It contains the nerve fibers running up and down the spinal cord in tracts. The gray matter is made up of nerve cells and is formed in the shape of an H when viewed on cross section
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In general, the white matter is the outer covering of the cord. It contains the nerve fibers running up and down the spinal cord in tracts. The gray matter is made up of nerve cells and is formed in the shape of an H when viewed on cross section
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In general, the white matter is the outer covering of the cord. It contains the nerve fibers running up and down the spinal cord in tracts. The gray matter is made up of nerve cells and is formed in the shape of an H when viewed on cross section
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The outflow portion of the sympathetic system starts with
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neuron cell bodies located in the lateral gray horns of the first thoracic to the second lumbar segments. In some cases, they may extend to the third lumbar segment. These cells are controlled by the hypothalamus via descending tracts of the reticular formation. The axons from the sympathetic nerve cells in the lateral gray horns leave the spinal cord in the anterior nerve roots and connect to the ganglia of the paraspinal sympathetic trunk. The sympathetic trunk is located along each side of the spinal column and extends along the entire length of the vertebral column. Axons arising from neurons in the sympathetic ganglia then travel throughout the body. The sympathetic fibers that innervate the heart arise primarily from the second to fourth thoracic segments.
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The outflow portion of the sympathetic system starts with
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neuron cell bodies located in the lateral gray horns of the first thoracic to the second lumbar segments. In some cases, they may extend to the third lumbar segment. These cells are controlled by the hypothalamus via descending tracts of the reticular formation. The axons from the sympathetic nerve cells in the lateral gray horns leave the spinal cord in the anterior nerve roots and connect to the ganglia of the paraspinal sympathetic trunk. The sympathetic trunk is located along each side of the spinal column and extends along the entire length of the vertebral column. Axons arising from neurons in the sympathetic ganglia then travel throughout the body. The sympathetic fibers that innervate the heart arise primarily from the second to fourth thoracic segments.
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The outflow portion of the sympathetic system starts with
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neuron cell bodies located in the lateral gray horns of the first thoracic to the second lumbar segments. In some cases, they may extend to the third lumbar segment. These cells are controlled by the hypothalamus via descending tracts of the reticular formation. The axons from the sympathetic nerve cells in the lateral gray horns leave the spinal cord in the anterior nerve roots and connect to the ganglia of the paraspinal sympathetic trunk. The sympathetic trunk is located along each side of the spinal column and extends along the entire length of the vertebral column. Axons arising from neurons in the sympathetic ganglia then travel throughout the body. The sympathetic fibers that innervate the heart arise primarily from the second to fourth thoracic segments.
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In evaluating patients with spinal cord injuries, the concepts of primary and secondary cord injury are important, basically...
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When the spinal cord is initially injured, the pathologic picture may be relatively benign, showing some scattered hemorrhages and edema.7 Several weeks later, the appearance is much worse, with large cavities surrounded by gliosis and fibrosis.7
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In evaluating patients with spinal cord injuries, the concepts of primary and secondary cord injury are important, basically...
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When the spinal cord is initially injured, the pathologic picture may be relatively benign, showing some scattered hemorrhages and edema.7 Several weeks later, the appearance is much worse, with large cavities surrounded by gliosis and fibrosis.7
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The blood supply to the spinal cord is, in general, not very substantial, and can be easily disrupted by either local trauma to the
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small anterior and posterior spinal arteries or injury and thrombosis to a large regional vessel, such as the great radicular artery of Adamkiewicz. General systemic hypotension and shock, if severe enough, can cause a low-flow state such that blood flow to the cord is compromised, even with an intact arterial supply.
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The blood supply to the spinal cord is, in general, not very substantial, and can be easily disrupted by either local trauma to the
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small anterior and posterior spinal arteries or injury and thrombosis to a large regional vessel, such as the great radicular artery of Adamkiewicz. General systemic hypotension and shock, if severe enough, can cause a low-flow state such that blood flow to the cord is compromised, even with an intact arterial supply.
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Patients with neurogenic shock are
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hypotensive and usually have warm, dry skin.8 Bradycardia is characteristic but not universal. The patient may lose the ability to redirect blood from the periphery to the core because of the loss of sympathetic tone resulting in excessive loss of heat from the skin, with subsequent hypothermia.8
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Patients with neurogenic shock are
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hypotensive and usually have warm, dry skin.8 Bradycardia is characteristic but not universal. The patient may lose the ability to redirect blood from the periphery to the core because of the loss of sympathetic tone resulting in excessive loss of heat from the skin, with subsequent hypothermia.8
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These symptoms of neurogenic shock can be expected to last
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from 1 to 3 weeks.9 In some cases, significant rehabilitation using elastic stockings, an abdominal binder, and a tilt table may be required to prevent an orthostatic drop in blood pressure when the patient is placed upright.10
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These symptoms of neurogenic shock can be expected to last
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from 1 to 3 weeks.9 In some cases, significant rehabilitation using elastic stockings, an abdominal binder, and a tilt table may be required to prevent an orthostatic drop in blood pressure when the patient is placed upright.10
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The anatomic level of the spinal cord injury influences the likelihood and severity of neurogenic shock.
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Any injury above T1 should be capable of disrupting the spinal tracts that control the entire sympathetic system. Any injury from T1 to L3 has the potential to partially disrupt the sympathetic outflow; intuitively, the higher the injury in this zone, the more likely or more severe the resulting neurogenic shock.1
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The anatomic level of the spinal cord injury influences the likelihood and severity of neurogenic shock.
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Any injury above T1 should be capable of disrupting the spinal tracts that control the entire sympathetic system. Any injury from T1 to L3 has the potential to partially disrupt the sympathetic outflow; intuitively, the higher the injury in this zone, the more likely or more severe the resulting neurogenic shock.1
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The anatomic level of the spinal cord injury influences the likelihood and severity of neurogenic shock.
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Any injury above T1 should be capable of disrupting the spinal tracts that control the entire sympathetic system. Any injury from T1 to L3 has the potential to partially disrupt the sympathetic outflow; intuitively, the higher the injury in this zone, the more likely or more severe the resulting neurogenic shock.1
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