PATHO: Ch. 20 Disorders of Brain Function

Tonic-clonic

________ seizures usually present with a person having a vague warning and experiencing a sharp tonic contraction of the muscles with extension of the extremities and immediate loss of consciousness.

Ischemic, hemorrhagic

________ strokes are caused by an interruption of blood flow in a cerebral vessel, and ________ strokes are caused by bleeding into brain tissue.

Epidural hematomas

________ usually are caused by head injury in which the skull is fractured.

Ischemic

Neuronal cell injury and death

Unprovoked

No identifiable cause can be determined

Vasogenic edema

Occurs when integrity of the blood-brain barrier is disrupted

hemorrhage

The most frequently fatal stroke is a spontaneous ________ into the brain.

Complex partial seizures

Begins in a localized are of the brain but may progress rapidly to involve both hemispheres

Complex partial

________ seizures involved impairment of consciousness and often arise from the temporal lobe.

Simple partial

________ seizures usually involve only one hemisphere and are not accompanied by loss of consciousness or responsiveness.

brain's

A number of regulatory mechanisms, including the blood-brain barrier and autoregulatory mechanisms that ensure an adequate blood supply, maintain the ________ electrically active cells.

tear

A subdural hematoma develops in the area between the dura and the arachnoid and usually is the result of a(n) ________ in the small bridging veins that connect veins on the surface of the cortex to dural sinuses.

seizure

A(n) ________ represents the abnormal behavior caused by an electrical discharge from neurons in the cerebral cortex.

embolic

A(n) ________ stroke is caused by a moving blood clot that travels from its origin to the brain.

Hydrocephalus

Abnormal increase in cerebrospinal fluid (CSF) volume in any part or all of the ventricular system

20

Although the brain makes up only 2% of the body weight, it receives 15% of the resting cardiac output and accounts for ________% of the oxygen consumption.

Hydrocephalus

An abnormal increase in cerebrospinal fluid volume in any part or all of the ventricular system

cerebral aneurysm

Aneurysmal subarachnoid hemorrhage represents bleeding into the subarachnoid space caused by a ruptured ________.

Brain herniation

Displacement of brain tissue under the falx cerebri or through the tentorial notch or incisura of the tentorium cerebelli

hypoxia

Because ________ indicates decreased oxygen levels in all brain tissue, it produces a generalized depressant effect on the brain.

herniation

Brain ________ represents a displacement of brain tissue under the flax cerebri or through the thentorial notch or incisura of the tentorium cerebelli.

brain

Brain death is defined as the irreversible loss of function of the ________, including the brain stem.

c. Electrocardiographic (ECG) findings

Brain death is the term used when irreversible loss of function of the entire brain occurs. A clinical examination must be done and repeated at least 6 hours later with the same findings for brain death to be declared. What is not assessed in the clinical examination for death? a. Blink reflex b. Responsiveness c. Electrocardiographic (ECG) findings d. Respiratory effort

Hypoxic

Can be focal or global, with only one part of the brain being underperfused or all of the brain being compromised

autoregulation

Cerebral ________ has been classically defined as the ability of the brain to maintain constant cerebral blood flow despite changes in systemic arterial pressure.

edema

Cerebral ________ is an increase in tissue volume secondary to abnormal fluid accumulation.

Cerebral edema

Cerebral hemispheres become enlarged, and the ventricular system beyond the point of obstruction is dilated. The sulci on the surface of the brain become effaced and shallow, and the withe matter is reduced in volume

focal, global

Cerebral ischemia can be ________, as in stroke, or ________, as in cardiac arrest.

Generalized onset

Clinical signs, symptoms, and supporting electroencephalographic (EEG) changes indicate involvement of both hemispheres at onset

Excitotoxic

Clouding of consciousness, bilaterally small pupils (approximately 2 mm in diameter) with a full range of constriction, and motor responses topain that are purposeful or semipurposeful (localizing) and often asymmetric

Tentorium cerebelli

Divides the cranial cavity into anterior and posterior fossae

Hypoxic

Decreased oxygen levels in all brain

Hydrocephalus

Depends on the brain's compensatory mechanisms and the extent of the swelling

Hypoxia

Deprivation of oxygen with maintained blood flow

Excitotoxic

Excessive activity of the excitatory neurotransmitters and their receptor-mediated effects

sodium

Excessive influx of ________ during neutral ischemia results in neuronal and interstitial edema.

d. Amygdala

For seizure disroders that do not respond to anticonvulsant medications, an option for surgical treatment exists. What is removed in the most common surgery for seizure disorders? a. Temporal neocortex b. Hippocampus c. Entorhinal cortex d. Amygdala

a.Intravenous (IV) diazepam

Generalized convulsive status epilepticus is a medical emergency caused by a tonic-clonic seizure that does not spontaneously end or recurs in succession without recovery. What is the first-line drug of choice to treat status epilepticus? a. Intravenous (IV) diazepam b. Intramuscular (IM) lorazepam c. IV cyclobenzaprine d. IM cyproheptadine

Brain herniation

Generalized depressant effect on the brain

a. Altered level of consciousness

Global and focal brain injuries manifest differently. What is almost always a manifestation of a global brain injury? a. Altered level of consciousness b. Change in behavior c. Respiratory instability d. Loss of eye movement reflexes

amino acids, proteases

In many neurologic disorders, various mediators, including excitatory ________, catecholamines, nitric oxide, free radicals, inflammatory cells, apoptosis, and intracellular ________ can cause injury to neurons.

Aphasia

Inability to comprehend, integrate, and express language

Increased intercranial volume and pressure

Increase in intercranial tissue causing an increase in intracranial pressure

intracranial

Increased ________ pressure is a common pathway for brain injury from different types of insults and agents.

Ischemic

Interferes with delivery of oxygen and glucose as well as the removal of metabolic wastes

a. Lumbar puncture

Intracranial aneurysms that rupture cause subarachnoid hemorrhage in the patient. How is the diagnosis of intracranial aneurysms and subarachnoid hemorrhage made? a. Lumbar puncture b. Magnetic resonance imagine (MRI) c. Loss of cranial nerve reflexes d. Venography

Macroneurons

Large cells with long axons that leave the local network of intercommunicating neurons to send action potentials to other regions of the nervous system

c. Brain edema and disturbances in blood flow

Manifestations of brain tumors are focal disturbances in brain function and increased intracranial pressure (ICP). What causes the focal disturbances manifested by brain tumors? a. Tumor infiltration and increased blood pressure b. Brain compression and decreased ICP c. Brain edema and disturbances in blood flow d. tumor infiltration and decreased ICP

Tonic-clonic

Most common major motor seizure

Absence seizures

Motion takes the form of automatisms such as lip smacking, mild clonic motion (usually in the eyelids), increased or decreased postural tone, and autonomic phenomena

a. Bowel and bladder incontinence, c. Lack of language comprehension, e. Variable preserved cranial nerve reflexes

Much as with brain death, there are criteria for the diagnosis of persistent vegetative state, and the criteria have to have lasted for more than 1 month. What are criteria for the diagnosis of persistent vegetative state? Mark all that apply. a. Bowel and bladder incontinence b. Ability to open the eyes c. Lack of language comprehension d. Lack of sufficient hypothalamic function to maintain life e. Variable preserved cranial nerve reflexes

muscle contractions

Myoclonic seizures involve brief, involuntary ________ induced by stimuli of cerebral origin.

Ischemia

Reduced or interrupted blood flow

Decorticate posturing

Results from lesions of the cerebral hemisphere

status epilepticus

Seizures that do not stop spontaneously or occur in succession without recovery are called ________.

a. Focal lesions of laceration, b. Contusion, d. Diffuse axonal, e. Hemorrhage

Several types of brain injuries can occur What are the primary (or direct) brain injuries? Mark all that apply. a. Focal lesions of laceration b. Contusion c. Hypoxic d. Diffuse axonal e. Hemorrhage

Microneurons

Small cells intimately involved in local circuitry

Cerebral edema

Swelling of the brain

vegetative

The ________ state is characterized by loss of all cognitive functions and the unawareness of self and surroundings.

primary, cerebral hypoxia

The effects of traumatic head injuries can be divided into two categories: ________ injuries, in which damage is caused by impact, and secondary injuries, in which damage results from the subsequent brain swelling, infection, or ________.

vasogenic

The functional manifestations of ________ edema include focal neurologic deficits, disturbances in consciousness, and severe intracranial hypertension.

d. 60 mm Hg

The regulation of cerebral blood flow is accomplished through both autoregulation and local regulation. This allows for the brain to meet its metabolic needs. What is the low parameter for blood pressure before cerebral blood flow becomes severely compromised? a. 30 mm Hg b. 40 mm Hg c. 50 mm Hg d. 60 mm Hg

cerebral artery

The specific manifestations of stroke of TIA are determined by the ________ that is affected by the area of brain tissue that is supplied by that vessel and by the adequacy of the collateral circulation.

carbon dioxide, hydrogen ion, oxygen

The three metabolic factors affect cerebral blood flow: ________, ________, and ________ concentration.

chemotherapy

The use of ________ for brain tumors is somewhat limited by the blood-brain barrier.

Atonic

These seizures also are known as drop attacks

Increased intercranial volume and pressure

Tissue perfusion becomes inadequate, cellular hypoxia results, and neuronal death can occur

Hemineglect

To attend to and react to stimuli coming from the contralateral side

ministroke, angina

Transient ischemic attack (TIA) or "________" is equivalent to "brain angina" and reflects a temporary disturbance in focal cerebral blood flow, which reverses before infarction occurs, analogous to ________ in relation to heart attack.

b. Burdzinski sign and Kernig sign

When the suspected diagnosis is bacterial meningitis, what assessment techniques can assist in determining the presence of meningeal irritation? a. Kernig sign and Chadwick sign b. Brudzinski sign and Kernig sign c. Brudzinski sign and Chadwick sign d. Chvostek sign and Guedel sign

b. Decorticate posturing

You are the nurse caring for a 31-year-old trauma victim admitted to the neurologic intensive care unit (ICU). During your initial assessment, you find that the patient is flexing arms, wrists, and fingers. There is abduction of the upper extremities with internal rotation and plantar flexion of the lower extremities. How would you describe this in your nursing notes? a. Decerebrate posturing b. Decorticate posturing c. Extensor posturing d. Diencephalon posturing

Thrombi

________ are the most common cause of ischemic strokes, usually occurring in atherosclerotic blood vessels.

Cytotoxic

________ edema involves an increase in intracellular fluid.

Lacunar

________ infarcts result from occlusion of the smaller penetrating branches of large cerebral arteries, commonly the middle cerebral and posterior cerebral arteries.

Consciousness

________ is the state of awareness of self and the environment and of being able to become oriented to new stimuli.

Stroke

________ is the syndrome of acute focal neurologic deficit from a vascular disorder that injures brain tissue.

Arteriovenous

________ malformations are a complex tangle of abnormal arteries and veins linked by one or more fistulas.

Vomiting

________ occurs with or without nausea, may be projectile, and is a common symptom of increased intracranial pressure (ICP) and brain stem compression.

Laminar necrosis

________ refers to short serpiginous segments of necrosis that occur within and parallel to the cerebral cortex, in areas supplied by the penetrating arteries during an ischemic event.

Encephalitis

________ represents a generalized infection of the parenchyma of the brain or spinal cord.