brain edema


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Related to brain edema: encephalitis

edema

 [ĕde´mah]
the accumulation of excess fluid in a fluid compartment. Formerly called dropsy and hydrops. adj., adj edem´atous. This accumulation can occur in the cells (cellular edema), in the intercellular spaces within tissues (interstitial edema), or in potential spaces within the body. Edema may also be classified by location, such as pulmonary edema or brain edema; types found in certain locations have specific names, such as ascites (peritoneal cavity), hydrothorax (pleural cavity), or hydropericardium (pericardial sac). Massive generalized edema is called anasarca. Classification by location does not indicate whether the edema is cellular or interstitial or occupies a potential space (for example, brain edema may be either cellular or interstitial). Edema can be caused by a variety of factors, including conditions that affect osmotic pressure, such as hypotonic fluid overload, which allows the movement of water into the intracellular space, or hypoproteinemia, which decreases the concentration of plasma proteins and permits the passage of fluid out of the blood vessels into the tissue spaces. Other factors include poor lymphatic drainage; conditions that cause increased capillary pressure, such as excessive retention of salt and water and heart failure; and conditions that increase capillary permeability, such as inflammation.
Edema formation. With trauma, increased capillary permeability and dilation cause leaking into tissue space. Initially clear, exudate in the tissue space becomes more viscous with an increase in plasma protein. From Copstead and Banasik, 2000.
alveolar edema pulmonary edema in the alveoli, usually with hypoxemia and dyspnea.
brain edema cerebral edema.
cardiac edema a manifestation of congestive heart failure, due to increased venous and capillary pressures and often associated with renal sodium retention.
cellular edema edema caused by the entry of water into the cells, causing them to swell. This may occur because of decreased osmolality of the fluid surrounding the cells, as in hypotonic fluid overload, or increased osmolality of the intracellular fluid, as in conditions that decrease the activity of the sodium pump of the cell membrane, allowing the concentration of sodium ions within the cell to increase.
cerebral edema swelling of the brain caused by the accumulation of fluid in the brain substance. It may result from head injury, stroke, infection, hypoxia, brain tumors, obstructive hydrocephalus, and lead encephalopathy; it may also be caused by disturbances in fluid and electrolyte balance that accompany hemodialysis and diabetic ketoacidosis. The most common type is vasogenic edema, which may result from increased capillary pressure or from increased capillary permeability caused by trauma to the capillary walls. Cellular edema may occur in ischemia or hypoxia of the brain. Because the brain is enclosed in the solid vault of the skull, edema compresses the blood vessels, decreasing the blood flow and causing ischemia and hypoxia, which in turn result in further edema. Unless measures are taken to reverse the edema, destruction of brain tissue and death will result.
dependent edema edema of the lowermost parts of the body relative to the heart; it is affected by gravity and position, so that the lower limbs are affected if the individual is standing, but the buttocks are affected if the individual is supine.
generalized edema edema that is caused by poor venous return; it is not localized by the effects of gravity, in contrast to dependent edema.
interstitial edema
1. edema caused by the accumulation of fluid in the extracellular spaces of a tissue.
2. pulmonary edema in the interstitial tissues; there is dyspnea but no hypoxemia.
edema neonato´rum sclerema neonatorum.
nonpitting edema edema in which pressure does not leave a depression in the tissues, such as in cellular edema. See also pitting edema.
pedal edema swelling of the feet and ankles.
peripheral edema edema affecting the extremities; seen in heart disease, Crohn's disease, and amyloidosis.
pitting edema edema in which external pressure leaves a persistent depression in the tissues (see pitting); it occurs because the pressure pushes the excess fluid out of the intercellular spaces in the tissue. See also nonpitting edema.
pulmonary edema diffuse extravascular accumulation of fluid in the tissues and air spaces of the lung due to changes in hydrostatic forces in the capillaries or to increased capillary permeability. It is most often symptomatic of left ventricular heart failure, but can also be a complication of mitral stenosis, aortic stenosis, altitude sickness, acute hypertension, volume overload during intravenous therapy, or reduced serum oncotic pressure, as in patients who have nephrosis, cirrhosis, or hypoalbuminemia.

During the initial stage of pulmonary edema, patients may complain of restlessness and anxiety and the feeling that they are getting a common cold. Other signs include a persistent cough, slight dyspnea, and intolerance to exercise. On auscultation, rales can be heard over the dependent portion of the lung. As fluid continues to fill the pulmonary interstitial spaces the dyspnea becomes more acute, respirations increase in rate, and there is audible wheezing. The cough becomes productive of frothy sputum tinged with blood, giving it a pinkish hue. Eventually, if the condition persists, the patient becomes less responsive to stimuli as levels of consciousness decrease. Ventricular arrhythmias develop and breath sounds diminish. In some patients these phases are telescoped as the pulmonary edema develops rapidly and the final stages of respiratory insufficiency are evident in a very short period of time.

Treatment is aimed at enhancing gas exchange, reducing fluid overload, and strengthening and slowing the heart beat. To accomplish these goals the patient is often given oxygen by mask or through mechanically assisted ventilation. Drug therapy includes diuretics to remove excess alveolar fluid and morphine to relieve anxiety and reduce the effort of breathing. Administration of other medications depends on the cause of the edema, as well as what other problems the patient may be having.
vasogenic edema that characterized by increased permeability of capillary endothelial cells; the most common form of cerebral edema.

ce·re·bral e·de·ma

brain swelling due to increased volume of the extravascular compartment from the uptake of water in the neuropil and white matter.
See also: brain swelling.
Synonym(s): brain edema

brain edema

brain edema

Cerebral edema Neurology Fluid accumulation outside the vascular compartment of the brain–ie, within cerebral tissue. Cf Brain edema.

ce·re·bral e·de·ma

(ser'ĕ-brăl ĕ-dē'mă)
Brain swelling due to increased volume of extravascular compartment from uptake of water in neuropil and white matter.
Synonym(s): brain edema.

brain

encephalon; that part of the central nervous system contained within the cranium, comprising the forebrain, midbrain and hindbrain, and developed from the embryonic neural tube. It is connected at its base with the spinal cord. The brain is a mass of soft, pinkish gray nerve tissue. For specific brain diseases see under headings relating to etiology and lesion.

brain abscess
common signs caused by an abscess in the brain are circling, rotation of the head, abnormal reflexes in one eye. The CSF may show evidence of infection.
brain aneurysm
see berry aneurysm.
brain anoxia
acute or chronic insufficiency of the blood supply to the brain causes anoxia which causes clinical signs that vary with the severity of the deprivation. Acute anoxia causes muscle tremor, recumbency, convulsions and death or recovery if the anoxia is relieved soon enough. Chronic anoxia causes lethargy, weakness, blindness and sometimes convulsions. In either case there may be permanent damage.
brain case
the cranium.
brain cestodal cyst
brain coup lesion
a derivation from contrecoup.
brain dead
irreversible coma with apnea, loss of all brainstem reflexes and absence of activity on an electroencephalogram.
brain decompression
relieving the pressure within the cranial vault. This may be done surgically by opening the cranium, or medically by administering hypertonic solutions of slowly metabolized materials, such as mannitol, intravenously.
brain edema
an important part of a number of acute diseases, e.g. lead poisoning, encephalitis, salt poisoning in swine, polioencephalomalacia of ruminants and hypoxia due to any cause. Clinically manifested by blindness, opisthotonos, nystagmus, recumbency and tonic convulsions. Inherited in polled and horned Herefords; calves are recumbent at birth and are never able to stand but consciousness is normal. See also neuraxial edema.
brain ependymal lining
brain hematoma
may occur with trauma, in extradural, subdural or intraparenchymal locations. They can cause progressive increase in intracranial pressure and eventually death.
brain hemorrhage
intracranial hemorrhage affecting the brain usually follows traumatic injury but spontaneous hemorrhage may result from an intrinsic vascular lesion. Loss of consciousness is a common sign followed by residual signs depending on the locality and size of the hemorrhage. Ataxia and convulsions are common sequelae.
brain herniation
displacement of brain from the cranial vault through the foramina (tentorial notch or foramen magnum) or ventral to dural septae. The usual causes are brain edema or hemorrhage with resulting increase in intracranial pressure.
brain hypoxia
see brain anoxia (above).
brain infarction
see feline ischemic encephalopathy.
brain ischemia
see brain anoxia (above).
brain laceration
occurs in cranial trauma that fractures the skull, causes severe acceleration or deceleration, or penetrates the skull and brain tissue.
brain necrosis
brain pigmentation
occurs in phalaris spp. poisoning; a characteristic greenish brown color grossly of the gray matter in brainstem nuclei and spinal cord, caused by a suspected lysosomal storage of granules of pigment material; usually associated with some degree of Wallerian degeneration within spinal cord tracts.
brain sand
brain scanning
a radiographic, magnetic or nuclear medical procedure for the detection of brain tumors, abscesses, hematomas and other intracranial lesions. Not widely used in veterinary medicine because of the expensive equipment required.
brain spongy degeneration
brain staggers
see dummy.
brain trauma
injury to the brain, including that caused by migrating worm larvae, will have diffuse effects including the development of edema, and local effects due to pressure by displaced bone or to hemorrhage. Initial shock, manifested as unconsciousness, is likely to be followed by residual localizing signs, e.g. facial paralysis, head rotation.
brain tumors
cause signs suggestive of local space-occupying lesion in the cranial cavity, including the increased intracranial pressure syndrome, blindness with disturbance of ocular reflexes, head rotation, circling and jacksonian epileptic episodes.
brain ventricles
see third, fourth, fifth ventricle.
References in periodicals archive ?
The treatment of Tan IIA significantly attenuated the brain edema formation as well as the infarct area determined at 24 h after ischemic injury (Fig.
Similarly, THR-18 reduced by more than twice the occurrence of brain edema (p<0.
Fishman RA: Brain edema and disorders of intracranial pressure.
Chan P, Longar S, Fishman R: Protective effects of liposome-entrapped superoxide dismutase on post-traumatic brain edema.
In acute liver failure, hyperammonemia can lead to cerebral hypertension, which can cause brain edema and death and may require a liver transplant.
The open-label Phase I/II study is designed to evaluate the tolerability of CRF in patients with peritumoral brain edema and to determine if the administration of CRF produced improvements in neurological symptoms or decreases in magnetic resonance imaging (MRI) measurements of peritumoral brain edema.
The company also presented data today demonstrating the potential of AST-120 to lower ammonia and reduce brain edema (swelling) in a preclinical model of cirrhosis.
Celtic Pharma")announced today that the databases have been locked and preliminary analyses completed on the two double-blinded studies of XERECEPT(R) (corticorelin acetate), as a treatment for peritumoral brain edema, as well as an initial database lock on the open-label study of XERECEPT's long-term safety and efficacy.
We are now conducting five studies of CRF in three indications; two Phase II studies in asthma, two Phase I/II studies in peritumoral brain edema and a Phase I/II study in rheumatoid arthritis.
Celtic Pharma") announced today that the databases have been locked and preliminary analyses completed on the two double-blinded studies of XERECEPT(R) (corticorelin acetate), as a treatment for peritumoral brain edema, as well as an initial database lock on the open-label study of XERECEPT's long-term safety and efficacy.
Two of the trials are designed to evaluate the safety and effects of CRF on peritumoral brain edema and the third is designed to evaluate the effect of CRF on rheumatoid arthritis.
The two-part study, consisting of a brain CT scan and a scoring system, showed Pycnogenol(R) lowered symptoms of jetlag such as fatigue, headaches, insomnia and brain edema (swelling) in both healthy individuals and hypertensive patients.