Today our topic of discussion is Tensilon Test (Edrophonium Bromide).
Tensilon Test (Edrophonium Bromide)
TENSILON TEST (EDROPHONIUM BROMIDE)
The Tensilon test is a pharmacological challenge study performed to assist in the diagnosis of myasthenia gravis. The drug used is edrophonium chloride (Tensilon), a short- acting form of the drug used to treat this disorder.
The test involves the IV administration of the drug before and during the performance of various muscular movements and the evaluation of these movements for changes in muscle strength. A positive diagnosis is made when the administration of the drug results in an improvement in muscle function. A negative diagnosis is made if muscle fasciculations occur as a result of the drug.
neuromuscular junction. It is caused by a deficiency of acetylcholine receptor sites on the muscle side of the junction. It is thought that the reduction in these sites is caused by an autoimmune response that blocks the receptor site and is responsible for receptor destruction.
The most prominent symptom of the disease is weakness of the involved muscles, which progresses in severity to all areas of the body.
Interfering factors: Corticosteroids, muscle relaxants, and anticholinergics, which can alter test results by their effect on muscle function or on the action of Tensilon.
Indications
Diagnosing myasthenia gravis when fatigue and muscle weakness are present, as revealed by an immediate improvement after injection of Tensilon Monitoring medication regimen of oral anti-cholinesterase to determine whether increase in dose is advised, as revealed by an improvement in muscle strength after IV Tensilon .
Determining whether an overdose is present, which can place the client in cholinergic crisis, as revealed by an exaggeration of muscle weakness after IV Tensilon.
Contraindications: Breathing difficulties or apneic conditions, because the disease can cause respiratory difficulties severe enough to require ventilatory support. Acetylcholine is a neurotransmitter chemical that nerve cells release to stimulate your muscles. People with a chronic disease called myasthenia.
Definition: A provocative best to diagnose myasthenia gravis, using endroonium bromide.
Purpose
- To diagnose myasthenia gravis
- To differentiate between myasthenia and cholinergic crisis.
Equipment
- Injection tray with tensilon
- Atropine
- Tuberculin syringe
- 1.5 mL syringe
- 500 ml. saline or dextrose as ordered
- Tourniquet Spirit
- Cotton balls
- K-basin
- Duster
- Resuscitation equipment 12 ventilator and ECG monitor
Procedure
- A medicine called Tensilon (also called edrophonium) or a dummy medicine (inactive placebo) is given during this test.
- The health care provider gives the medicine through one of your veins (intravenously, through an IV).
- You may also be given a medicine called atropine before receiving
- Tensilon so that you do not know you are getting the medicine.
- You will be asked to perform some muscle movements over and over again, such as crossing and uncrossing your legs or getting up from a sitting position in a chair.
- The provider will check whether the Tensilon improves your muscle strength.
- If you have weakness of the eye or face muscles, the effect of the Tensilon on this will also be monitored.
- The test may be repeated and you may have other Tensilon tests to help tell the difference between myasthenia gravis and other -conditions (Fig. 29.76).
Method
- Dosing: 2 mg of edrophonium is administered intravenously as a test dose
- Monitoring heart rate: Bradycardia or ventricular fibrillation may develop.
- After observing for about 2 minutes, if no clear response develops
- Up to 8 additional mg of edrophonium is injected. double-blind protocol with a saline injection as placebo has been advocated.
- Testing should be performed with patient free of all cholinesterase-inhibitor medications.
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