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Patho_exam 3
Question | Answer |
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Seizure | Sudden, explosive, disorderly discharge of cerebral neurons and is characterized by a sudden, transient alteration in brain function, usually involving motor, sensory, autonomic, or psychic clinical manifestations and a temporary altered level of arousal. |
Convulsion | A term sometimes applied to seizures, refers to the jerky, contract-relax (tonic-clonic) movement associated with some seizures |
Epilepsy | seizure activity for which no underlying correctable cause for the seizure can be found; therefore seizure activity recurs without treatment |
Tonic phase | muscle contraction with increased muscle tone; excitation of the subcortical, thalamic, and brain stem areas correspond to the tonic phase |
Clonic phase | alternating contraction and relaxation of muscles; begins when inhibitory neurons in the cortex, anterior thalamus, and basal ganglia react to the cortical excitation |
Agnosia | more severe form of dysphasia and an inability to communicate |
Dysphasia | impairment of comprehension or production of language with impaired communication |
Expressive dysphasia | Broca dysphasia, motor; nonfluent, cannot find words, difficulty writing; relatively intact verbal comprehension; impaired repetition |
Receptive dysphasia | Wernicke dysphasia, sensory; fluent, can produce verbal language but is meaningless, with inappropriate words; impaired repetition |
Acute confusional states | transient disorders of awareness that result from cerebral dysfunction secondary to drug intoxication, metabolic disorders, nervous system disease, trauma, or surgery; arise from disruption of neural network; impaired or lost detection, no concentration |
Delirium | acute state of brain dysfunction associated with right upper muddle-temporal gyrus or left temporal-occipital junction disruption and several neurotransmitters are involved; difficulty concentrating, restlessness, irritable, insomnia, poor appetite |
Hypokinetic confusional state | associated with right-sided frontal-basal ganglion disruption; interfere with neuronal metabolism or synaptic transmission; occur with pt who have fevers or metabolic disorders; decrease in mental function, forgetfulness is prominent |
Uncal herniaton (supratentorial) | occurs when uncus or hippocampal gyrus, or both, shifts from the middle fossa thru the tentorial notch into posterior fossa, compressing ipsilateral 3rd cranial nerve. s/s: dec LOC, pupils sluggish, cheyne-stokes respirations, appearance of decorticate |
Infratentorial Herniation | cerebellar tonsil shifts thru foramen magnum bc of increased pressure. s/s: arched stiff neck, paresthesias in shoulder area, dec LOC, respiratory abn, pulse rate variations |
Central Herniation (supratentorial) | downward shift of the diencephalon thru tentorial notch. Cause: injury or mass. s/s: rapid unconsciousness, apnea, small reactive pupils then dilate, decerebration |
Hydrocephalus | excess fluid in cerebral ventricles, subarachnoid space. inc pressure and dilation cause atrophy of cerebral cortex. Rapid deep coma if not treated STAT with acute state. dec memory & cognitive state |
Hypotonia | decrease muscle tone, passive movement occurs with little or no resistance. cause: pure pyramidal tract damage and cerebellar damage. Tire easily and are weak. Difficulty rising from sitting position, sitting without arm support, walking up and down stair |
Hypertonia | increase muscle tone, passive movement occurs with resistance. tire easily and are weak. may atrophy due to decreased use |
Huntington's Disease | aka Chorea, hereditary, degenerative hyperkinetic movement disorder. age 25-45. gene located on short arm of Chrom 4. s/s chorea, athetosis, ballism. Chorea beings in face and arms(irreg movements) |
Parkinson's Disease | Patho: degeneration of basal ganglia with dysfunctional or misfolded alpha-synuclein protein and loss of dopamine producing neurons. s/s tremor, rigidity, difficulty walking, weakness, dysphagia, slurred speech, drooling, constipation, depression |
Subdural hematoma | bleeding between the dura matter and the brain, acute develop rapidly, chronic found in elderly, act like expanding masses and increase intracranial pressure and compressing the bleeding vessels. |
Extradural hematoma | bleeding between the dura matter and the skull, artery is source of bleeding, temporal fossa is most common site of extradural hematoma caused by injury to the middle meningeal artery or vein |
Intracerebral hematoma | bleeding within the brain, associated with contusions, dec LOC, coma or confusional state from other injuries |
Acute spinal cord injury | Microscopic hemorrhages appear in the central gray matter and pia-archnoid, inc in size until the entire gray matter is hemorrhagic and necrotic. Edema in the white matter occurs, impairing the microcirculation of the cord |
During spinal cord swelling, what is the MOST important concern that can also be life threatening? | ischemia to tissues; may be life-threatening bc it may impair the diaphragm functions (phrenic nerves exit at C3-C5) and vegetative functions (mediated by the medulla oblongata) |
A seizure that starts in your finger and progressively spreads up the arm and then extends down to the leg with NO LOC is what type of seizure? | focal motor; jacksonian seizure |
Meningitis | inflammation of the brain or spinal cord. causes include bacteria, viruses, fungi, parasites, or toxins. May be acute, subacute, or chronic |
Bacterial meningitis | primarily an infection of the pia matter and arachnoid, the subarachnoid space, the ventricular system, and CSF. s/s: fever, tachycardia, chills, rash, HS, positive Kernig & Brudzinski sign, dec LOC, seizures |
Aseptic meningitis (viral, nonpurulent) | is believed to be limited to the meninges. Produces various symptoms and caused by several infectious agents, primarily viruses. s/s: same as bacterial but milder |
Fungal meningitis | chronic, much less common condition than bacterial or viral meningitis. most often in persons with impaired immune responses or alterations in normal body flora. s/s: develop slowly and insidiously. First sign often dementia or communicating hydrocephalus |
Encephalitis | acute febrile illness, usually viral with nervous system involvement. Caused by arthropod-borne(mosquito-borne) virus and herpes simplex. |
West Nile Virus | Common cause of epidemic meningoencephalitis and leading cause of arboviral encephalitis. s/s: fever, HA, stiff neck, vision loss, altered mental status ranging from confusion to coma |
Multiple Sclerosis | acquired autoimmune inflammatory disorder involving destruction of axonal myelin in the brain and spinal cord. Viral insult to the nervous system has occured in genetically susceptible ppl. s/s: parethesias of the face, trunk, or limbs, weakness, visual |
Myasthenia gravis | acquired chronic autoimmune disease mediated by antibodies agaisnt the acetylcholine receptor at the neuromuscular junction, and is characterized by muscle weakness and fatigability. Results from a defect in nerve impulse transmittion. |
Myasthenia crisis | occurs when severe muscle weakness causes extreme quadriparesis or quadriplegia, respiratory insufficiency with SOB, and extreme difficulty in swallowing. In danger of respiratory arrest. |
Positive Kernig sign | straightening the knee with the hip and knee in a flexed position produces pain in the back and neck regions |
Positive Brudzinski sign | passive flexion of the neck produces neck pain and increased rigidity |
Decorticate posturing | upper extremeties flexed at the elbows and held close to the body and by lower extremeties that are externally rotated and extended; occur when the brain stem is not inhibited by the cerebral cortex motor area |
Decerebrate posturing | increased tone in extensor muscles and trunk muscles, with active tonic neck reflexes. When the head is in a neutral position, all four limbs are rigidly extended. Caused by severe injury to brain and brain stem |
Basal ganglia | Basal ganglia system is believed to exert a stabilizing effect on motor movements. Parkinson's and Huntington's Disease are conditions associated with defects of basal ganglia. |
The Basal ganglia effects what type of motor movements when referring to Parkinson's or Huntington's disease? | involuntary or exaggerated motor movements |
CSF fluid | clear, colorless fluid similar to blood plasma and interstitial fluid. |
ventricles | small cavities |
Choroid plexuses | structures that produce CSF, arise from the pial membrane |
Arachniod villi | protrude from the arachnoid space, through the dura matter, and lie within the blood flow if the venous sinuses. Function as one way valves directing CSF outflow into the blood but preventing blood flow into the subarachnoid space |
Vagus nerve and what happens when stimulate it? | Cranial nerve X; stimulation in the gastrointestinal tract inc peristalsis and secretion, as well as the relaxation of sphincters. |
Cranial nerve I | Olfactory; purely sensory; fibers arise from nasal olfactory epithelium and form synapses with olfactory bulbs, which transmit impulses to temporal lobe; purely sensory, carries impulses for sense of smell; tested by sniffing aromas with each nostril |
Cranial nerve II | Optic; purely sensory, carries impulses for vision; vision and visual field tested with an eye chart |
Cranial nerve III | Oculomotor; contains motor fibers to eye; pupils examined for size shape and equality, reflex tested with penlight |
Cranial nerve IV | Trochlear; motor; tested in common with cranial nerve III and ability to follow moving objects |
Cranial nerve IX | Glossopharyngeal; motor and sensory; gag and swallow reflexes checked, subject asked to speak and cough |
Cranial nerve X | Vagus; sensory and motor; same as cranial nerve IX because they both serve muscles of throat |
Which alpha receptor is responsible for pupil dilation, vasoconstriction, dec gastrointestinal motility, and goose bumps? | Alpha 1 |
Beta receptors | classified as B1 adrenergic receptors (facilitate heart rate and contractility and cause of release of renin from kidney) AND B2 adrenergic (all remaining effects attributed to Beta receptors) |
Ganglia | Most cell bodies are located within the CNS; those in the PNS usually are found in groups called ganglia |
Dendrites | extensions that carry nerve impulses toward the cell body |
Axons | long, conductive projections from the cell body that carry nerve impulses away from the cell body |
Myelin | segmented layer of lipid material covering an axon which is an insulating substance that speeds impulse propagation |
What is purpose of myelin sheath? | referred to as entire membrane |
Does nerve impulses travel faster or slower when they are myelinated? | Faster |
Nociceptors and where are they located? | Free nerve endings in the afferent peripheral nervous system that selectively respond to different types of stimuli. Located through out the body but are not evenly distributed so the relative sensitivity to pain differs according to their locations. |
Circadian rhythm and responsibility | Internal temperature varies in response to activity, environmental temperature, and daily fluctuation (circadian rhythm). |
Thermoregulation | mediated primarily by the hypothalamus. Peripheral thermoreceptors in the skin and hypothalamus, spinal cord, abdominal organs, and other central locations provide the hypothalamus with info about skin and core temperature |
Methods of heat production: Chemical reactions of metabolism | Chemical reactions of metabolism: occur during ingestion and metabolism of food and while maintaining body at rest (basal metabolism); occur in body core |
Methods of heat loss | Radiation, conduction, convection, vasodilation, evaporation, decreased muscle tone, increased respiration, voluntary mechanisms, adaptation to warmer climates |
Heat stroke | potentially lethal result of an overstressed thermoregulatory center. Very high core temp (>104F). regulatory center ceases to function and the body's heat loss mechanisms fail. s/s: high temp, absence of sweating, rapid pulse, confusion, agitation, coma. |
Heat cramps | severe, spasmodic cramps in the abdomen and extremities that follow prolonged sweating and associated with sodium loss. s/s: fever, rapid pulse, increased BP |
Heat exhaustion | results from prolonged high core or environmental temperatures, which cause profound vasodilation and profuse sweating, leading to dehydration, dec plasma volumes, hypotension, dec cardiac output, and tachycardia. s/s: weakness, dizziness, fainting |
Malignant hyperthermia | lethal complication of rare inherited muscle disorder that may be triggered by inhaled anesthetics and depolarizing muscle relaxants. Altered calcium function in muscle cells with hypermetabolism, uncoordinated muscle contractions, inc muscle work, inc O2 |
Hypothermia | produces depression of the central nervous and respiratory systems, vasoconstriction, alterations in microcirculation and coagulation, and ischemic tissue damage. |
What is ischemic tissue damage and what is the effect on the body? | occurs when blood supply to an area of tissue has been cut off; ex. MI, stroke, thrombotic event; tissue becomes necrotic due to lack of O2. |
What are the reasons therapeutic hypothermia are utilized? | used to slow metabolism and preserve ischemic tissue during surgery, after cardiac arrest or following neurologic injury. |
What is sleep? | active brain process that provides restorative functions and promotes memory consolidations. |
Suprachiasmastic nucleus | Suprachiasmatic nucleus in the hypothalamus controls the timing of the sleep-wake cycle and coordinates this cycle with circadian rhythms |
REM | initiated by REM-on and REM-off neurons in the pons and mesencephalon. Occurs every 90 min beginning 1-2 hrs after nREM sleep begins. Aka paradoxical sleep bc the EEG pattern is similar to the normal awake pattern and brain is very active with dreaming |
NREM | accounts for 75-80% of sleep time. initiated when inhibitory signals are released from the hypothalamus. Temp, HR, BP, RR, and muscle tone decrease Growth hormone is released with corticosteroid levels depressed |
Insomnia | inability to fall asleep or stay asleep. may be transient, lasting a few days and related to travel across time zones or by acute stress. can be idiopathic, or R/T drug or alcohol abuse, pain, depression, aging |
OSAS | Obstructive sleep apnea syndrome; upper airway obstruction with excessive snoring and multiple apneic episodes that last 10 seconds or longer. |
Hypersomnia | excessive daytime sleepiness; associated with OSAS; may fall asleep while driving a car, working, or even while conversing, with significant concerns for safety. |
Narcolepsy | primary hypersomnia of central origin characterized by hallucinations, sleep paralysis, and rarely catplexy(brief spells of muscle weakness); hypothalamic hypocretin deficiency may be r/t immune-mediated destruction of hypocretin secreting cells |
Viral conjunctivitis | caused by an adenovirus; contagious, with s/s of watering, redness, and photophobia. |
Allergic conjunctivitis | associated with a variety of antigens, including pollens |
Chronic conjunctivitis | results from any persistent conjunctivitis |
Sensory-discriminative system | mediated by the somatosensory cortex and is responsible for identifying the presence, character, location, and intensity of pain |
Affective motivational system | determines an individual's conditioned avoidance behaviors and emotional responses to pain. mediated thought reticular formation, limbic system, and brain stem |
Cognitive evaluative system | overlies the individuals learned behavior concerning the experience of pain and therefore can modulate perception of pain. Mediated through cerebral cortex |
Pain modulation | involves many different mechanisms that inc or dec transmission of pain signals thru nervous system. Modulation can occur before during or after pain is perceived. |
Level of consciousness | state of awareness both of oneself and the environment and a set of responses to that environment; response to external stimuli |
Methods of heat production: Skeletal muscle contraction | gradual increase in muscle tone or rapid muscle oscillations (shivering) |
Methods of heat production: Chemical thermogenesis | Epinephrine is released and produces rapid, transient increase in heat production by raising basal metabolic rate; quick, brief effect that counters heat loss through conduction and convection; involves brown adipose tissue |
Therapeutic hypothermia effects and cautions | stresses the heart, leading to v-fib and cardiac arrest; exhausts liver glycogen stores by prolonged shivering; surface cooling may cause burns, frostbite, and fat necrosis; immunosuppression with inc infection risk; slows drug metabolism |
Benign Tumors | Grows slowly, have a well defined capsule, are not invasive, well differentiated, look like tissue from which they arise, have a low mitotic index, dividing cells are rare, no NOT metastasize |
Malignant Tumors | grow rapidly, are not encapsulated, invade local structures and tissues, poorly differentiated, may not be able to determine tissue of origin, high mitotic index, many dividing cells, can spread distantly, often thru blood vessels and lymphatics |
Tumor | used initially to describe a swelling but now reserved for new growth or neoplasm |
Cancer | refers to malignant tumor or neoplasm |
Benign tumor | can still be life threatening based on size and location such as a benign meningioma at the base of skull |
Not all tumors or neoplasm are cancer | |
Carcinomas | cancers arising in epithelial tissue |
Adenocarcinomas | if the cells arise or form ductal or glandular structures; malignant tumor arising from breast glandular tissue is a mammary adenocarcinoma |
Carcinoma in situ (CIS) | early stage growths are localized; these growths are not malignant; can progress to invasive and metastatic cancers; found in cervix, skin, oral cavity, esophagus, lg bowel, stomach |
Point mutations | most common, events are small scale changes in DNA |
Chromosome translocations | large changes in chromosome structure; a piece of chromosome is translocated to another chromosome |
Inflammation, immunity, and cancer | active immune response in chronic inflammation predisposes to cancer; individuals who suffer with UC for 10 years or more have inc risk of developing cancer; chronic viral hepatitis caused by Hep B or C inc risk of liver cancer |
HPV | infects basal skin cells and commonly causes warts; increase in sexual partners can lead to an increase in cancer risk |
EBV | when individuals are immunosuppressed because of HIV; persistent EBV infection can lead to the development of B cell lymphomas |
Risk factors for cancer | Tobacco: most important cause of cancer; diet, obesity, alcohol consumption, ionizing radiation, ultrasonic radiation, sexual and reproductive behavior, physical activity, personal behavior, air pollution, occupational hazards, hormones-estrogen;table10-1 |
Mechanisms of carcinogenesis | Cancer as a multistage process: 1. initiation; DNA alteration or cell change 2. tumor-promotion; from single mutated cell to formation of tumor 3. tumor-progression; development of malignancy |
TNM classification of cancer | T: Tumor from primary to skin and/or chest wall invasion N: nodes from no nodes involved to fixed nodes M: metastasis from non to suspected and distant metastasis |
Stages of Cancer spread | Stage 1: confined to organ of location Stage 2/B: locally invasive Stage 3/C: spread to local structure like lymph nodes Stage 4/D: spread to distant sites, liver to lung, prostate to bone, ovarian seeding |
Induction chemotherapy | seeks to cause shrinkage or disappearance |
Adjuvant chemotherapy | given after surgical excision of a cancer with the goal of eliminating micrometastases |
Neoadjuvant chemotherapy | given before localized treatment of a cancer |
Radiation | May induce or increase genomic instability by facilitating new mutations |
Ultraviolet radiation | sunlight CAUSES basal cell carcinoma and squamous cell carcinoma |
Developmental plasticity | the degree to which an organism's development is contingent on its environment; requires stable gene expression |