clonic convulsion

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Related to clonic convulsion: Tonic clonic seizure


a type of seizure consisting of a series of involuntary contractions of the voluntary muscles. Such seizures are symptomatic of some neurologic disorder; they are not in themselves a disease entity. Convulsions can be produced by any of a number of chemical disorders, such as hypoglycemia and hypocalcemia; metabolic disturbances and hormonal imbalances; brain cell injury from head trauma, tumors, degenerative neural disease, and stroke; anoxia and hemorrhage which deprive brain cells of vital substances; acute cerebral edema which interferes with normal brain cell function; and infection and high fever (€febrile convulsions). Finally, epilepsy is one of the most common of all disorders associated with convulsions.
Patient Care. The plan for patient care should take into account the potential for injury to the patient during a seizure. This includes observing the patient before, during, and after each convulsion, and when possible, preventing or minimizing environmental factors and events in the patient's daily life that are believed to precipitate a seizure.

Protection of the patient from injury is of primary concern. Once a seizure has begun, the person with the patient should remain calm, summon help, and try to help prevent injury to the patient, using mild restraint in order to avoid allowing the extremities to strike nearby hard objects. Vigorous restraint can cause orthopedic injuries, as the muscles contract strongly against resistance. Whatever the location, the patient should not be moved until after the seizure is over. If the patient has some warning and there is time before the seizure actually begins, a soft oral airway or folded towel can be placed between the teeth to prevent tongue biting. Hard objects should never be used to force open the mouth. It is not only useless to attempt this once the jaws are firmly fixed, but teeth can be broken and soft tissues severely injured by trying to force something into the mouth and between the teeth.

It is especially important to observe and report what happened before, during, and immediately after a seizure. This is a critical source of information in the diagnosis of the disorder leading to the convulsion. Observations should include: (1) the time the convulsion began, whether the patient had any warning or specific symptoms just before it, and the length of time it lasted; (2) where the seizure began and what parts of the body were involved; (3) whether the eyes deviated, and a description of the patient's level of consciousness before and during the seizure; (4) whether there was incontinence of urine or stool, vomiting, bleeding, or foaming or frothing at the mouth; (5) the effects of the seizure on the patient's pulse and respirations, and any other objective signs, such as change in skin color or profuse perspiration; and (6) the condition of the patient after the seizure was over (postictal symptoms and signs), such as lethargy, mental confusion, or speech impairment.

Careful attention to environmental factors such as noise or bright light, pain, exhaustion, and other seizure triggers can help identify conditions that might have precipitated seizure activity. Emotional events also should be considered as possible stimulants that can elicit uncontrollable activity.

If the seizures are recurring, as in epilepsy, the patient and the significant others will need instruction in the nature of the illness, an explanation of the prescribed regimen for medications, a list of potential seizure triggers that could precipitate an attack, how to prevent injury during a seizure, and when notification of the health care provider is indicated.
central convulsion a convulsion not triggered by any external cause but due to a lesion of the central nervous system; called also essential convulsion.
clonic convulsion a convulsion marked by alternating contracting and relaxing of the muscles. See also generalized tonic-clonic seizure.
epileptiform convulsion any convulsion attended by loss of consciousness.
essential convulsion central convulsion.
febrile convulsion a seizure occurring in children age 3 months to 5 years in association with a fever at or above 39.5° C (103.2° F), often associated with a family history of febrile seizures. Treatment of children with febrile seizures with no evidence of neurologic dysfunction is usually limited to diagnosis and treatment of the underlying cause of the fever. Phenobarbital may be used to treat the seizure or used prophylactically when the child is ill or is receiving childhood immunizations. Called also febrile seizure.
tetanic convulsion a tonic spasm without loss of consciousness and often associated with hypocalcemia. See also tetany.
tonic convulsion prolonged contraction of the muscles, as a result of an epileptic discharge. See also generalized tonic-clonic seizure.
uremic convulsion one due to uremia, or retention in the blood of material that should have been expelled by the kidneys.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

clo·nic con·vul·sion

a convulsion in which the contractions are intermittent, the muscles alternately contracting and relaxing.
Farlex Partner Medical Dictionary © Farlex 2012

clo·nic con·vul·sion

(klon'ik kŏn-vŭl'shŭn)
A convulsion in which the contractions are intermittent, the muscles alternately contracting and relaxing.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

clo·nic con·vul·sion

(klon'ik kŏn-vŭl'shŭn)
Convulsion with intermittent contractions; the muscles alternately contract and relax.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Groups Dose Latency Time to Mortality Tonic clonic (mg/kg time death rate convulsions i.g.) (min) (min) rate Control 1.3 [+ or 7.9 [+ or 100% 100% -]0,15 -] 2.15 AMEE 200 4.0 [+ or 19.6 [+ or 50% 100% -] 1.7 -] 3.6 ** AMEE 100 2.4 [+ or 16.9 [+ or 60% 100% -] 0.37 -]3.7 * AMEE 50 1.3 [+ or 7.1 [+ or 90% 100% -]0.17 -] 2.7 Diazepam 5 27.6 [+ or 27.7 [+ or 10% 10% -] 2,4 -] 2.3 ** Effects of AMEE in the latency time, time to death, mortality rate and tonic clonic convulsions rate induced by pentylenetetrazol (n = 10).
CASE REPORT: A 20--year--old primigravida with 9 months amenorrhea and in labour was referred from some Delhi Hospital with history of three episodes of generalized tonic clonic convulsions since morning.
(9) Lopez et al reported that three patients with atlanto-occipital fusion have had cervical pain and two patients had tonic or clonic convulsions. (10) Iwata et al reported a case of atlanto-occipital fusion with unusual neurological symptoms.
CASE SUMMERY: A 2 year 3 month old male toddler born to non-consanguineous couple with normal birth and developmental history with a past history suggestive of measles at the age of 9 months presented with progressively increasing myoclonic jerks, ataxia, generalized tonic clonic convulsions and cognitive decline over a period of past 3 months.