Synonyms: liver flap, flapping tremor, wrist flap
Alternative sites showing the motor disturbance: tongue, eyelids, fingers and elbows
Regular testing method:
(1) The patient is asked to hold both arms outstretched anteriorly.
(2) The wrists are held dorsiflexed (fingers pointing up at 90 degrees to the forearms). Sometimes the examiner will briefly push the fingers towards the trunk, then release the fingers.
(3) The fingers and hands are observed for 30 seconds.
(4) A person with asterixis will have the fingers move back and forth from the vertical.
Clinical Findings
|
Grade
|
no flapping
|
0
|
rare flapping
|
1
|
occasional flapping, usually irregular
|
2
|
frequent flapping
|
3
|
almost continuous or continuous
|
4
|
If the patient is conscious but unable to hold the arms out, then the patient can be asked to squeeze 2 fingers steadily.
Limitations:
• Asterixis is not specific for hepatic encephalopathy.