Define Asterixis and its causes, types, symptoms, diagnostic test, treatment and pictures

What is Asterixis?

Asterixis word comes from Greek words “a” means not and “sterixis” means fixed position. Asterixis is defined as an involuntary muscle disorder or tremor, which involves movements of hands and wrists similar to the flapping of the wings. It can also be defined as arrhythmic flexion movements of hands with outstretched arms.

What is the meaning of Asterixis?
What is the meaning of Asterixis?

This is a condition in which tremor or muscle movements are involuntary which is totally out of control of the patient. Flapping of wrists, irregular movements of the hands and lateral movements of the fingers are common symptoms of this disorder. This condition is also known as a liver flap or flapping tremor. Asterixis is of mainly two types based upon how it affects, laterally or bilaterally. The most common type of Asterixis is Bilateral Asterixis. It is also observed in tongue or foot.

What are the types of Asterixis?

There are two types of Asterixis depends upon how it affects you.

Bilateral asterixis

Bilateral asterixis is mainly caused by metabolic encephalopathies especially hepatic and renal. The hepatic failure that causes bilateral Asterixis is known as “liver flap”. Electrolyte abnormalities, drug intoxication, cardiac and respiratory diseases are other main causes of bilateral asterixis. Bilateral asterixis that caused by electrolyte abnormalities is hypoglycemia, hypokalemia, and hypomagnesemia. Another possible cause of bilateral asterixis is drug intoxication which includes barbiturate intoxication, alcoholism, and phenytoin flap (phenytoin intoxication). Wilson’s disease and focal brain lesions in the rostral midbrain tegmentum may also cause asterixis.

Unilateral Asterixis

These are most commonly due to focal brain lesions in the genu and anterior portion of the internal capsule or ventrolateral thalamus. Lesions in the midbrain, parietal cortex, and medial frontal cortex may also cause unilateral asterixis.

What is the pathophysiology of Asterixis?

Diencephalic motor centers of the brain are the center that is responsible for involuntary or uncontrolled jerking. The uncontrolled jerking may lead to abnormal functioning of the muscles of the arms and wrists. When there is damage to the brain cells occurs, it can lead to hepatic encephalopathy. It is so because the liver stops its normal functioning and it may lead to abnormal ammonia metabolism (metabolize the ammonia to urea). The exact mechanism of the asterixis is still unknown and there are many studies undergoing to find the right perspective of the disease.

What are the symptoms of Asterixis?

Asterixis is a motor disorder, symptoms of which include:

  • Inability to maintain a neutral wrist position or a fixed position.
  • Hand tremors with interrupted muscle contraction causing postural lapses with a frequency of 3 – 5 Hz.
  • Arrhythmic jerks or movement of the hands, wrists, and fingers with outstretched hands.
  • Irregular “flapping” of hands.
  • Involuntary movements.
  • Pain and discomfort in hands.
  • Weakness in arms.

What is Asterixis, Know its Causes, Symptoms, Treatment

What are the causes of Asterixis?

Internal malfunction such as when your brain gets jumbled messages to do the things are the indication of involuntary muscles. This is what happens when you suffer from asterixis.

Abnormal functions of the diencephalic motor centers in the brain are not responsible for asterixis. Diencephalic motor centers regulate the muscles involved in maintaining a position which is rarely affected in asterixis. The liver is most commonly affected by this and may lead to liver failure; there are other many causes of asterixis such as:

  • Acute respiratory failure
  • Azotemia
  • Brain issues like subarachnoid hemorrhage, intracerebral hemorrhage, and subdural hematoma
  • Congestive heart failure
  • Chronic renal failure
  • The excess accumulation of CO2 in the blood
  • Hypomagnesemia
  • Hypoglycemia
  • Hypokalemia
  • Metabolic encephalopathy
  • Wilson’s disease

Apart from such cases, there is a number of medications which can be responsible for asterixis. Some examples of such medications are: alcohol, barbiturates, lithium, carbamazepine, phenytoin, sodium valproate, gabapentin, ceftazidime, and metoclopramide.

What are the risk factors associated with Asterixis?

There are several risk factors associated with asterixis and it is quite common to understand. Excessive alcohol consumption is the main risk factor also the people with brain or systemic disorder is most prone to this disorder.  Other high-risk conditions are cardiac, kidney, and respiratory diseases. Few drugs can also occur as risk factors.

How to diagnosis asterixis?

Diagnosis of asterixis is similar to most diagnoses and examinations. In the diagnosis of the asterixis, your doctor will discuss your medical history; he may also ask you about any kind of damage to your brain or liver in the past. After getting the proper information about your medical history, he will conduct a physical exam.

He may ask you to extend your arms, spreading the fingers, and then flexing at the wrists. He may add some pressure on your wrists to find out the inactive tremors and extra pressure can activate the tremors and help the doctor in diagnosis.

If the doctor finds some tremors, he may recommend you to undergo some more tests such as CT scans, blood work, and nerve conditions studies.

How to treat asterixis?

The reason of causing asterixis can determine the treatment of the asterixis. Once the doctor came to know about the severity of the damage done, only then he can decide the treatment. Your doctor can switch your medications from more powerful to lesser ones. In severe cases, such as brain or liver injury, an intense treatment may be needed which depends upon how much issue is needed treatment.

When to see a doctor if you have asterixis?

When you feel like the involuntary flapping of the hands, and you think the situation is not in your control, you should immediately see a doctor. Sometimes, a patient is not able to understand what is going on and what could be the reason behind such tremors, in such cases, a medical history and a physical examination by a doctor can be helpful. So instead of finding solutions at home, you should always rush to the doctor in such cases.

For others still, you may not be able to do anything at all. Regardless, you must remember that it is a symptom of a bigger issue. And the sooner you respond to your symptoms, the sooner you can get a full diagnosis of your medical issues and, hopefully, have time to set them right.

How long does it take to heal a strained trapezius muscle?
Do adults get strep throat? How long does it take to recover from strep throat?