Concept Review for Patho Final Exam
Vegetative state verses brain death
• Vegetative state
➢ Loss of awareness and intellectual function but continued brainstem function
▪ Result of diffuse brain damage
▪ Person unresponsive to external stimuli
▪ If consciousness recovered may have significant neuro impairment.
• Locked-in syndrome
➢ Individual is aware and capable of thinking but is paralyzed and cannot communicate due to brain
damage (may only be able to move their eyes to say yes or no)
• Criteria for brain death (declared clinically and legally dead)
➢ Cessation of brain function
▪ Including function of the cortex and the brainstem
▪ Flat or inactive electroencephalogram (EEG)
➢ Absence of brainstem reflexes or responses
➢ Absence of spontaneous respirations when ventilator assistance is withdrawn
➢ Establishment of the certainty of irreversible brain damage by confirmation of cause of the dysfunction
➢ Evaluation twice by different physicians
Indicators of increased ICP
• Brain is encased in rigid, nonexpendable skull.
• Fluids, blood, and CSF are not compressible.
• Increase in fluid or additional mass causes increase in pressure in the brain
➢ Ischemia and eventual infarction of brain tissue
• Increased ICP is common in many neurological problems.
➢ Brain hemorrhage, trauma, cerebral edema, infection, tumors, abnormal circulation of CSF
• Early signs—if cause is not removed
➢ Decreasing level of consciousness or decreased responsiveness (lethargy) 1st sign often
➢ Severe headache
▪ From stretching of dura and walls of large blood vessels
➢ Vomiting
▪ Often projectile, not associated with food intake
▪ Result of pressure stimulating the emetic center in the medulla
➢ Papilledema (visualize w ophthalmoscope)
▪ Caused by increased ICP and swelling of the optic disc
• Vital signs
➢ Development of cerebral ischemia
▪ Vasomotor centers respond in attempt to increase arterial blood supply to brain (causes
vasoconstriction) *known as Cushing reflex
➢ Systemic vasoconstriction
, ▪ Increase of systemic blood pressure—more blood to brain to relieve ischemia
➢ Baroreceptor response
▪ In carotid arteries
▪ Increased blood pressure by slowing heart rate
➢ Chemoreceptor response
▪ Respond to low carbon dioxide levels
▪ Reduction of respiratory rate
➢ Improved cerebral circulation
▪ Relieves ischemia
▪ Short time
▪ Increasing ICP causes ischemia to recur; cycle will repeat
• ICP continues to rise, blood pressures rises
➢ Increased pulse pressure is significant in people with ICP. (difference bt systolic and diastolic); caused
by slow heart rate and intermittent rapid cycling of the Cushing’s reflex
Brain tumors
• Space-occupying lesions that cause increased ICP
• Benign and malignant tumors can be life-threatening.
➢ Unless accessible and removable
• Gliomas form the largest category of primary malignant tumors
➢ Classified according to cell derivation and location of the tumor
• Primary malignant tumors rarely metastasize outside the CNS.
• Secondary brain tumors
➢ Metastasize from breast or lung tumors
➢ Cause effects similar to those of primary brain tumors
• Signs and symptoms
➢ Site of tumor determines focal signs
➢ Seizures often first sign
➢ Headaches (increased ICP), vomiting, lethargy, irritability, personality and behavioral changes, possible
unilateral facial paralysis or visual problems
➢ Do not cause systemic signs of malignancy
▪ Will cause death before they cause general effects
• Treatment—may cause damage to normal CNS tissue
➢ Surgery if tumor is accessible
➢ Chemotherapy and radiation (many are radioresistant)
• Interference with blood supply
➢ Local damage and manifestations depend on cerebral artery involved
• Hemorrhage
➢ Increased ICP will cause local ischemia and generalized symptoms.
• Global cerebral ischemia
➢ Impaired perfusion of entire brain
▪ Loss of function and generalized cerebral edema
▪ Brain death if not reversed quickly
TIA’s: Transient Ischemic Attack
• May occur singly or in a series
• Result from temporary localized reduction of blood flow in the brain
➢ Partial occlusion of an artery
➢ Atherosclerosis
, ➢ Small embolus
➢ Vascular spasm
• Signs and symptoms
➢ Difficult to diagnose after the attack
➢ Directly related to location of ischemia
➢ Intermittent short episodes of impaired function
▪ e.g., muscle weakness in arm or leg
➢ Visual disturbances
➢ Numbness and paresthesia in face
➢ Transient aphasia or confusion may develop
▪ Repeated attacks may be a warning sign for obstruction related to atherosclerosis.
CVA’s: Cerebrovascular Accidents
• A CVA (stroke) is an infarction of brain tissue that results from lack of blood.
➢ Occlusion of a cerebral blood vessel
➢ Rupture of cerebral vessel
• 5 minutes of ischemia causes irreversible nerve cell damage.
➢ Central area of necrosis develops
➢ All function lost
➢ Surrounded by an area of inflammation; this zone will regain function following healing.
• MRI can determine cause of the stroke
• Risk factors include:
➢ Diabetes, hypertension, systemic lupus erythematosus, atherosclerosis, history of TIAs, increasing age,
obstructive sleep apnea, heart disease, smoking, sedentary lifestyle
➢ Combination of oral contraceptives and cigarette smoking
➢ Congenital malformation of blood vessels
➢ Increasing age
• F.A.S.T. – Signs of Stroke Should Prompt FAST Action
➢ The American Stroke Association developed this easy-to-remember guide to help identify the signs of a
stroke.
▪ F – Face drooping. Is one side of the person’s face drooping or numb? When he or she smiles, is
the smile uneven?
▪ A – Arm weakness. Is the person experiencing weakness or numbness in one arm? Have the
person raise both arms. Does one of the arms drift downward?
▪ S – Speech difficulty. Is the person’s speech suddenly slurred or hard to understand? Is he or
she unable to speak? Ask the person to repeat a simple sentence. Can he or she repeat it back?
▪ T – Time to call 9-1-1. If any of these symptoms are present, dial 9-1-1 immediately. Check the
time so you can report when the symptoms began.
, • Treatment
➢ Clot-busting agents
➢ Surgical intervention
➢ Glucocorticoids
➢ Supportive treatment
➢ Occupational and physical therapists; speech-language pathologists
➢ Treat underlying problem to prevent recurrences.
➢ Rehabilitation begins immediately.
Meningitis
• Inflammation of the membranes (meninges) surrounding the brain & spinal cord
• Can be caused by:
➢ Viral (most common in US) usually mild and clears on it’s own if person has normal immune response
➢ Bacterial (serious and can be fatal) 2 vaccines available that cover four strands
➢ Other rare causes: fungal parasitic, amebic, non-infectious (cancer, lupus, etc)
• Different age groups are susceptible to infection by different causative organisms.
• Children and young adults
➢ Neisseria meningitidis or meningococci
➢ Frequently carried in the nasopharynx of asymptomatic carriers
➢ Spread by respiratory droplets
➢ Occurs more frequently in late winter and early spring
• Neonates
➢ Escherichia coli most common causative organism
➢ Usually in conjunction with a neural tube defect, premature rupture of the amniotic membranes,
difficult delivery
• Young children
➢ Most often caused by Haemophilus influenzae
▪ More often in the autumn or winter
• Older adults
➢ Streptococcus pneumoniae—major cause
• Signs and symptoms
➢ Sudden onset is common.
➢ Severe headache
➢ Back pain
➢ Photophobia
➢ Nuchal rigidity
➢ Kernig sign (next slide)
➢ Brudzinski sign (next slide)
Vegetative state verses brain death
• Vegetative state
➢ Loss of awareness and intellectual function but continued brainstem function
▪ Result of diffuse brain damage
▪ Person unresponsive to external stimuli
▪ If consciousness recovered may have significant neuro impairment.
• Locked-in syndrome
➢ Individual is aware and capable of thinking but is paralyzed and cannot communicate due to brain
damage (may only be able to move their eyes to say yes or no)
• Criteria for brain death (declared clinically and legally dead)
➢ Cessation of brain function
▪ Including function of the cortex and the brainstem
▪ Flat or inactive electroencephalogram (EEG)
➢ Absence of brainstem reflexes or responses
➢ Absence of spontaneous respirations when ventilator assistance is withdrawn
➢ Establishment of the certainty of irreversible brain damage by confirmation of cause of the dysfunction
➢ Evaluation twice by different physicians
Indicators of increased ICP
• Brain is encased in rigid, nonexpendable skull.
• Fluids, blood, and CSF are not compressible.
• Increase in fluid or additional mass causes increase in pressure in the brain
➢ Ischemia and eventual infarction of brain tissue
• Increased ICP is common in many neurological problems.
➢ Brain hemorrhage, trauma, cerebral edema, infection, tumors, abnormal circulation of CSF
• Early signs—if cause is not removed
➢ Decreasing level of consciousness or decreased responsiveness (lethargy) 1st sign often
➢ Severe headache
▪ From stretching of dura and walls of large blood vessels
➢ Vomiting
▪ Often projectile, not associated with food intake
▪ Result of pressure stimulating the emetic center in the medulla
➢ Papilledema (visualize w ophthalmoscope)
▪ Caused by increased ICP and swelling of the optic disc
• Vital signs
➢ Development of cerebral ischemia
▪ Vasomotor centers respond in attempt to increase arterial blood supply to brain (causes
vasoconstriction) *known as Cushing reflex
➢ Systemic vasoconstriction
, ▪ Increase of systemic blood pressure—more blood to brain to relieve ischemia
➢ Baroreceptor response
▪ In carotid arteries
▪ Increased blood pressure by slowing heart rate
➢ Chemoreceptor response
▪ Respond to low carbon dioxide levels
▪ Reduction of respiratory rate
➢ Improved cerebral circulation
▪ Relieves ischemia
▪ Short time
▪ Increasing ICP causes ischemia to recur; cycle will repeat
• ICP continues to rise, blood pressures rises
➢ Increased pulse pressure is significant in people with ICP. (difference bt systolic and diastolic); caused
by slow heart rate and intermittent rapid cycling of the Cushing’s reflex
Brain tumors
• Space-occupying lesions that cause increased ICP
• Benign and malignant tumors can be life-threatening.
➢ Unless accessible and removable
• Gliomas form the largest category of primary malignant tumors
➢ Classified according to cell derivation and location of the tumor
• Primary malignant tumors rarely metastasize outside the CNS.
• Secondary brain tumors
➢ Metastasize from breast or lung tumors
➢ Cause effects similar to those of primary brain tumors
• Signs and symptoms
➢ Site of tumor determines focal signs
➢ Seizures often first sign
➢ Headaches (increased ICP), vomiting, lethargy, irritability, personality and behavioral changes, possible
unilateral facial paralysis or visual problems
➢ Do not cause systemic signs of malignancy
▪ Will cause death before they cause general effects
• Treatment—may cause damage to normal CNS tissue
➢ Surgery if tumor is accessible
➢ Chemotherapy and radiation (many are radioresistant)
• Interference with blood supply
➢ Local damage and manifestations depend on cerebral artery involved
• Hemorrhage
➢ Increased ICP will cause local ischemia and generalized symptoms.
• Global cerebral ischemia
➢ Impaired perfusion of entire brain
▪ Loss of function and generalized cerebral edema
▪ Brain death if not reversed quickly
TIA’s: Transient Ischemic Attack
• May occur singly or in a series
• Result from temporary localized reduction of blood flow in the brain
➢ Partial occlusion of an artery
➢ Atherosclerosis
, ➢ Small embolus
➢ Vascular spasm
• Signs and symptoms
➢ Difficult to diagnose after the attack
➢ Directly related to location of ischemia
➢ Intermittent short episodes of impaired function
▪ e.g., muscle weakness in arm or leg
➢ Visual disturbances
➢ Numbness and paresthesia in face
➢ Transient aphasia or confusion may develop
▪ Repeated attacks may be a warning sign for obstruction related to atherosclerosis.
CVA’s: Cerebrovascular Accidents
• A CVA (stroke) is an infarction of brain tissue that results from lack of blood.
➢ Occlusion of a cerebral blood vessel
➢ Rupture of cerebral vessel
• 5 minutes of ischemia causes irreversible nerve cell damage.
➢ Central area of necrosis develops
➢ All function lost
➢ Surrounded by an area of inflammation; this zone will regain function following healing.
• MRI can determine cause of the stroke
• Risk factors include:
➢ Diabetes, hypertension, systemic lupus erythematosus, atherosclerosis, history of TIAs, increasing age,
obstructive sleep apnea, heart disease, smoking, sedentary lifestyle
➢ Combination of oral contraceptives and cigarette smoking
➢ Congenital malformation of blood vessels
➢ Increasing age
• F.A.S.T. – Signs of Stroke Should Prompt FAST Action
➢ The American Stroke Association developed this easy-to-remember guide to help identify the signs of a
stroke.
▪ F – Face drooping. Is one side of the person’s face drooping or numb? When he or she smiles, is
the smile uneven?
▪ A – Arm weakness. Is the person experiencing weakness or numbness in one arm? Have the
person raise both arms. Does one of the arms drift downward?
▪ S – Speech difficulty. Is the person’s speech suddenly slurred or hard to understand? Is he or
she unable to speak? Ask the person to repeat a simple sentence. Can he or she repeat it back?
▪ T – Time to call 9-1-1. If any of these symptoms are present, dial 9-1-1 immediately. Check the
time so you can report when the symptoms began.
, • Treatment
➢ Clot-busting agents
➢ Surgical intervention
➢ Glucocorticoids
➢ Supportive treatment
➢ Occupational and physical therapists; speech-language pathologists
➢ Treat underlying problem to prevent recurrences.
➢ Rehabilitation begins immediately.
Meningitis
• Inflammation of the membranes (meninges) surrounding the brain & spinal cord
• Can be caused by:
➢ Viral (most common in US) usually mild and clears on it’s own if person has normal immune response
➢ Bacterial (serious and can be fatal) 2 vaccines available that cover four strands
➢ Other rare causes: fungal parasitic, amebic, non-infectious (cancer, lupus, etc)
• Different age groups are susceptible to infection by different causative organisms.
• Children and young adults
➢ Neisseria meningitidis or meningococci
➢ Frequently carried in the nasopharynx of asymptomatic carriers
➢ Spread by respiratory droplets
➢ Occurs more frequently in late winter and early spring
• Neonates
➢ Escherichia coli most common causative organism
➢ Usually in conjunction with a neural tube defect, premature rupture of the amniotic membranes,
difficult delivery
• Young children
➢ Most often caused by Haemophilus influenzae
▪ More often in the autumn or winter
• Older adults
➢ Streptococcus pneumoniae—major cause
• Signs and symptoms
➢ Sudden onset is common.
➢ Severe headache
➢ Back pain
➢ Photophobia
➢ Nuchal rigidity
➢ Kernig sign (next slide)
➢ Brudzinski sign (next slide)
