Alterations in Cognitive systems Flashcards
Alterations in arousal
- structural
- metabolic alterations
- psychogenic or psychiatric
Neuro functions critical to eval process
- LOC
- Pattern of breathing
- pupillary reaction
- oculomotor responses
- motor responses
Obtundation
-mild to moderate reduction in arousal w/ limited response to the environment; falls asleep unless verbally or tactilely stimulated; answers questions w/ minimum responses
stupor
-condition of deep sleep or unresponsiveness; person may be aroused or caused to open eyes only by vigorous and repeated stimulation; responses is often withdrawal or grabbing at sitmulus
S/S of alterations in arousal: pattern of breathing
-helps eval level of brain dysfunction and level of coma
-posthyperventilation apnea: lower brainstem centers regulate breathing pattern
-cheyne-stokes respirations
-central neurogenic hyperventilation
-cluster respirations
-ataxic respirations
apneustic respirations
cheyne-stokes respirations
-abnormal rhythm of breathing w/ alternating periods of hyperventilation and apnea
Central neurogenic hyperventilation
-sustained hyperventilation caused by a lesion in the central pons
apneustic respirations
-prolonged inspiratory and expiratory phases caused by injury to the pons or upper medulla
cluster respirations
-periods of clusters of rapid respirations of near or equal depth, resulting from trauma or compressions to the medulla or from chronic opioid abuse
Ataxic respirations
-irregular respirations w/ prolonged periods of apnea associated w/ damage to the medulla
Dilated, fixed pupils
- Ischemia/hypoxia
- atropine/scopolamine
- barbiturate intoxication
- hypothermia
- Opiates: pinpoint pupils
Oculomotor responses
- doll’s eyes
- help determine the levels of brain dysfunction
Brain death (total brain death)
- body cannot maintain internal homeostasis
- irreversible cessation of the entire brain, including brainstem and cerebellum occurs
Brain death criteria
- completion of all appropriate, therapeutic procedures
- unresponsive coma (absence of motor and reflex responses)
- No spontaneous respirations (apnea)
- no brainstem function
- isoelectric (flat) electroencephalography (EEG) for 6-12 hours
Cerebral death
- irreversible coma
- death of the cerebral hemispheres, exclusive of the brainstem and cerebellum
- no behavioral or environmental responses
- brain continues to maintain normal respiratory and cardiovascular functions, temp, control and metabolic functioning
Dysmnesia
-Retrograde amnesia: loss of past memories
-anterograde amnesia
inability to form new memories
Agnosia
- failure to recognize the form and nature of objects
- Can be tactile, visual, auditory
Dysphagias
- wernicke
- conductive
- anomic
- transcortical
- broca aphasia
- global aphasia
Acute confusional states
Disruption of reticular-activating system of upper brainstem and its projections to the thalamus, basal ganglion, and specific areas of the cortex and limbic areas
Hyperactive delrium
- agitated delirium
- excited delirium syndrome
acute state of brain dysfunction
-Associated w/ the right middle temporal gyrus or disruption of the left temporo-occipital junction
Hypoactive delirium: hypoactive confusional state
-is associated w/ the disruption of the right-sided, frontal-basal ganglion
S/S Delrium
- autonomic nervous system overactivity
- typical development of over 2-3 days
- difficulty concentrating
- restlessness and irritability
- insomnia
- tremulousness
- poor appetite
Dementia
- progressive failure of cerebral functions that cause impairment
- pathophys:
- -neuron degeneration
- -compression of brain tissue
- -athersclerosis of cerebral vessels
- -brain trauma
- -genetic predisposition
- -CNS infections
Alzheimer type
- Dementia of the alzheimer type DAT
- Specific dx can only be made by postmortem exam
- leading cause of dementia
- is irreversible
- neurofibrillary tangles
- neuritic plaques
- degeneration of basal forebrian cholinergic neurons (loss of acetylcholine)
Tx alzheimer disease
- no disease-arresting therapies are available
- cholinesterase inhibitors can enhance cholinergic transmission
- antiamyloid drugs
Frontotemporal dementia
- was previously called pick disease
- rare, severe degenerative disease of the frontal lobes
- age onset: younger than 60 yrs
- familial association
Increased ICP
- Stage 1: vasoconstriction and external compression
- stage 2: continued expansion of intracranial content
- stage 3: brain hypoxia and hypercapnia; autoregulation lost
- stage 4: brain herniates; several herniation syndromes
Herniation
- shifting of brain tissue
- -disrupts blood flow and damages brain tissue
- types: uncal, supratentorial, central, cingulate gyrus, transclavarial, infratentorial
supratentorial herniation
involves the temporal lob and hippocampal gyrus, shifting from the middle fossa to the posterior fossa
infratentorial hernation
involves shift of the cerebellar tonsils through the foramen magnum
Cerebral edema types
- vasogenic: clinically the most important type
- cytotoxic: toxic factors affect the brain parenchyma
- interstitial: volume increases around the ventricles
Hydrocephalus
- Variety of conditions
- excess fluid accumulation w/in the cerebral ventricles, subarachnoid space or both
- caused by interference in cerebrospinal fluid flow
- -decreased reabsorption
- -increased fluid production
- -obstruction in the ventricular system
- Surgery. shunt
Noncommunicating (obstructive) (intraventricular) hydrocephalus
-caused by obstruction
Hypotonia
-Decreased muscle tone
Hypertonia
increased muscle tone
- Spasticity
- paratonia (gegenhalten): resistance to passive movement
- dystonia: increased involuntary muscle contraction
- Rigidity: firm and tense muscles
Hyperkinesia
- excessive movement
- chorea, wandering, tremors at rest, postural tremors
Paroxysmal dyskinesias
abnormal, involuntary movements that occurs as spasms
Tradive dyskinesia
- slow onset, usually from antipsych agents
- rapid, repititive, stereotypic movements
Huntington disease
-aka chorea
-rate, autosomal dominant hereditary-degenerative disorder(short arm chromosome 4)
-severe degeneration of striatum and basal ganglia
-abnormal movements that occur w/ conscious effort, dementia, emotional liability
-no known tx, symptomatic drug therapy
-
Akinesia
-absence of voluntary movement
Parkinsons disease
-severe degeneration of basal ganglia (corpus striatum) involves dopaminergic nigrostriatal pathway
S/S Parkinsons
- rigidity
- postural abnormalities
- autonomic-neuroendrocrine symptoms
- cognitive-affective symptoms and dementia
- loss of dopaminergic-pigmented neurons in substantia nigra
- bradykinesia and akinesia
- resting tremor
Manifestations of Parkinsons
- wide-eyed unblinking staring expression w/ immobile facial muscles
- frequent drooling
- slow gait
- short, shuffling steps
- flexed and abducted arms held stiffly at the side
- slightly forward bending
Tx of parkinsons
- drug therapy: levodopa, anticholinergic drugs, antihistamines, amantadine
- surgery
- rehab
- OT
Upper and lower motor neuron syndromes
- paresis: weakness, partial paralysis
- upper motor neuron syndromes: hemiparesis and hemiplegia
- diplegia (both upper and lower)
- parapesis or paraplegia (lower)
- quadriparesis or quadriplegia
- pyramidal motor syndrome: spinal shock-loss of function below lesion
Motor neuron diseases
- progressive degeneration of the upper or lower motor neurons in spinal cord, brainstem, and cortex
- Amyotrophic lateral sclerosis (ALS)
- Paralytic poliomyelitis
- progressive spinal muscular atrophy
- progressive bulbar palsy
- bulbar palsy
- inflammatory process may injure or destroy anterior horn cells or cranial nerve cell bodies
Amyotrophic lateral sclerosis (ALS)
- AKA sporadic motor system disease, Lou Gehrig disease
- degenerative disorder diffusely involving the lower ad upper motor neurons
- movement is more affected than the brain
- Progressive muscle weakness leads to respiratory failure
ALS s/s
- limb cramping or weakness
- incoordination
- slurring of speech
- single muscle group paresis that spreads
- hypotonia
- difficulty swallowing
ALS Tx
- administer riluzole (Rilutek), and antiglutamate which is standard tx that prolongs life for months but doesn’t cure
- maintain quality of life
- involve family in the tx
Decorticate
-posturing towards body
Decerebrate
-posturing away from body
Frontal lobe ataxic
- wide based
- body sways and falls
- loss of truncal motion
- gait ignition failure
- start hesitation
- shuffling
- freezing
Extrapyramidal motor syndromes: basal ganglia
- involvement of either a paucity or an excess of movements
- rigidity w/ cogwheel phenomenon
- alterations in posture and muscle tone
Extrapyramidal motor syndromes: cerebellar motor syndrome
- chiefly ipsilateral (same side)
- loss of muscle tone
- ataxia
- muscle weakness
- disorders of equilibrium, posture and gait
