thyroid crisis


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Related to thyroid crisis: thyrotoxic crisis

crisis

 [kri´sis] (pl. cri´ses) (L.)
1. the turning point of a disease for better or worse; especially a sudden change, usually for the better, in the course of an acute disease.
2. a sudden paroxysmal intensification of symptoms in the course of a disease.
addisonian crisis (adrenal crisis) the symptoms accompanying an acute onset or worsening of addison's disease: anorexia, vomiting, abdominal pain, apathy, confusion, extreme weakness, and hypotension; if untreated these progress to shock and then death.
aplastic crisis a sickle cell crisis in which there is temporary bone marrow aplasia.
blast crisis a sudden, severe change in the course of chronic granulocytic leukemia, characterized by an increased number of blasts, i.e., myeloblasts or lymphoblasts.
catathymic crisis an isolated, nonrepetitive act of violence that develops as a result of intolerable tension.
celiac crisis an attack of severe watery diarrhea and vomiting producing dehydration and acidosis, sometimes occurring in infants with celiac disease.
developmental crisis maturational crisis.
hemolytic crisis an uncommon sickle cell crisis in which there is acute red blood cell destruction with jaundice.
hypertensive crisis dangerously high blood pressure of acute onset.
identity crisis a period in the psychosocial development of an individual, usually occurring during adolescence, manifested by a loss of the sense of the sameness and historical continuity of one's self, confusion over values, or an inability to accept the role the individual perceives as being expected by society.
life crisis a period of disorganization that occurs when a person meets an obstacle to an important life goal, such as the sudden death of a family member, a difficult family conflict, an incident of domestic violence (spouse or child abuse), a serious accident, loss of a limb, loss of a job, or rape or attempted rape.
maturational crisis a life crisis in which usual coping mechanisms are inadequate in dealing with a stress common to a particular stage in the life cycle or with stress caused by a transition from one stage to another. Called also developmental crisis.
myasthenic crisis the sudden development of dyspnea requiring respiratory support in myasthenia gravis; the crisis is usually transient, lasting several days, and accompanied by fever.
oculogyric crisis a symptom of an acute dystonic reaction in which the person demonstrates a fixed gaze, usually upward; also, the uncontrollable rolling upwards of the eye. It can be a result of encephalitis or a reaction to antipsychotic medications.
salt-losing crisis see salt-losing crisis.
sickle cell crisis see sickle cell crisis.
tabetic crisis a painful paroxysm occurring in tabes dorsalis.
thyroid crisis (thyrotoxic crisis) see thyroid crisis.
vaso-occlusive crisis a sickle cell crisis in which there is severe pain due to infarctions in the bones, joints, lungs, liver, spleen, kidney, eye, or central nervous system.

thyroid

 [thi´roid]
2. pertaining to the thyroid gland.
4. a preparation of thyroid gland from domesticated food animals, containing levothyroxine and liothyronine and used as replacement therapy in the diagnosis and treatment of hypothyroidism and the prevention and treatment of goiter and thyroid carcinoma; administered orally.
thyroid crisis a sudden and dangerous increase of the symptoms of thyrotoxicosis, seen in patients with severe hyperthyroidism or in the period immediately following a thyroidectomy. (However, good postoperative care and the use of radioiodine ablation techniques have greatly reduced the incidence of this once common postoperative complication.) Called also thyroid or thyrotoxic storm.



Thyroid crisis is a serious event that can be fatal if not brought under control. All of the body processes are accelerated to dangerously high levels. The pulse may rise to 200 beats per minute, and there is concurrent rise in the respiratory rate. The temperature control center loses control, bringing about a rapid and steady increase in body temperature. Pulmonary edema and congestive heart failure can also occur.

Treatment is aimed at correction of the hyperthyroidism, control of the symptoms, and prevention of further crisis by treating the underlying cause. Medications are employed to block synthesis of thyroid hormones, block their release, and inhibit conversion of triiodothyronine to thyroxine. plasmapheresis. plasma exchange, or hemodialysis may be necessary to remove the hormones from the circulation.

Supportive care includes administration of oxygen and measures to control hyperthermia, such as the use of ice packs or a hyperthermia blanket. Intravenous hydration is important to prevent shock. The use of glucocorticoids is associated with improved survival rates. propranolol, sympatholytics, and guanethidine are often used, as well as other medications that treat symptoms.
thyroid function test a test of the functioning of the thyroid gland, such as its proper production of thyroid hormones. See radioiodineuptake test, thyroid-stimulating hormone test, thyrotropin-releasing hormone test, and triiodothyronine resin uptake test.
thyroid gland the largest of the endocrine glands, consisting of two lateral lobes connected by an isthmus; a third pyramidal lobe sometimes extends up from the isthmus. The thyroid gland is located in the front and sides of the neck just below the thyroid cartilage and produces hormones that are vital in maintaining normal growth and metabolism (see thyroid hormones). It also serves as a storehouse for iodine.



Diagnostic tests for thyroid disorders include radioimmunoassay for T3, T4, and thyroid-stimulating hormone (TSH), free thyroxine serum concentration, and free thyroxine index (FTI). These and other thyroid function tests can be distorted by preparations and foods containing iodine, and by oral contraceptives, phenytoin (Dilantin), and several other drugs. The thyroid scan is useful in detecting nodules and active thyroid tissue and, combined with radioactive iodine uptake, measures the ability of the thyroid gland to take in ingested iodine.

Persons who received radiation to the head and neck as children are at higher than normal risk for development of thyroid abnormalities. Of these disorders about one-third are carcinomas of the thyroid. Other problems related to radiation early in life include adenomas and other malignant and benign tumors, hypo- and hyperthyroidism, and thyroiditis. The American Thyroid Association suggests periodic laboratory testing and physical assessment of persons at high risk in order to detect these abnormalities when they are more amenable to treatment.
Thyroid gland.
thyroid hormones iodothyronines secreted by the thyroid gland, principally thyroxine (tetraiodothyronine or T4) and triiodothyronine (T3). The serum level of T4 is normally 45 to 50 times the level of T3. However, T3 is several times more active than T4, and most T3 is produced by metabolism of T4 in peripheral tissues. The pharmaceutical names for T4 and T3 are levothyroxine and liothyronine, respectively. Thyroid hormones influence many metabolic processes. They stimulate the cellular production of heat; stimulate protein synthesis; regulate many aspects of carbohydrate metabolism; stimulate lipid synthesis, mobilization, and degradation; stimulate the synthesis of coenzymes from vitamins; and may affect the response of tissues to epinephrine and norepinephrine.



Secretion of thyroid hormones is regulated by the hypothalamus-pituitary-thyroid control system. Internal environmental conditions, such as low thyroid hormone and norepinephrine serum levels, or external factors, such as cold and stress, activate the hypothalamus, which secretes thyrotropin-releasing hormone (TRH). This hormone acts on the pituitary gland and brings about the release of thyroid-stimulating hormone (TSH). The TSH then stimulates the release of thyroid hormones such as T3 and T4 from the thyroid gland. When sufficient levels of serum thyroxine and other thyroid hormones have been reached, there is negative feedback to the hypothalamus and TRH is no longer secreted. See also hypothyroidism and hyperthyroidism.
thyroid-stimulating hormone test a thyroid function test in which thyrotropin (thyroid-stimulating hormone) is administered intramuscularly and the thyroid gland is monitored over time with scintiscanning or radioimmunoassays for a response or areas of decreased responsiveness. Called also TSH test and TSH stimulation test.

thy·ro·tox·ic cri·sis

, thyroid crisis
the exacerbation of symptoms of hyperthyroidism; severe thyrotoxicosis; can follow shock or injury or thyroidectomy; marked by rapid pulse (140-170/minute), nausea, diarrhea, fever, loss of weight, extreme nervousness, and a sudden rise in the metabolic rate; coma and death may occur; occasionally the entire clinical picture is that of profound prostration, weakness, and collapse, without the phase of muscular overactivity and tachycardia.
Synonym(s): thyroid storm

thyroid crisis

Etymology: Gk, thyreos, shield, eidos, form, krisis, turning point
a sudden exacerbation of symptoms of thyrotoxicosis, characterized by fever, sweating, tachycardia, extreme nervous excitability, and pulmonary edema. It usually occurs in a patient whose thyrotoxicosis treatment is inadequate, and the paroxysm is triggered by a stressful infection or injury. If untreated, the crisis is often fatal. Also called thyroid storm, thyrotoxic crisis. See also Graves' disease.

thy·ro·tox·ic cri·sis

, thyroid crisis (thī'rō-tok'sik krī'sis, thī'royd)
The exacerbation of symptoms that occurs in severe thyrotoxicosis; marked by rapid pulse, nausea, diarrhea, fever, loss of weight, and extreme restlessness; coma and death may occur.
Synonym(s): thyroid storm.

thy·ro·tox·ic cri·sis

, thyroid crisis (thī'rō-tok'sik krī'sis, thī'royd)
Exacerbation of symptoms of hyperthyroidism; marked by rapid pulse, nausea, diarrhea, fever, loss of weight, extreme nervousness, and sudden rise in metabolic rate; coma and death may occur. Also called thyroid storm.

thyroid crisis (thī´roid),

n a sudden exacerbation of symptoms of thyrotoxicosis characterized by fever, sweating, tachycardia, extreme nervous excitability, and pulmonary edema. If untreated, the crisis often is fatal. Also called
thyroid storm.