I believe you may be referring to asterixis (flapping tremor).
"asterixis/ flapping tremor - An exaggerated muscle tremor characterized by involuntary jerking of the hand in flexion and extension, classically seen in advanced liver disease and hepatic encephalopathy"
The doc will ask you to fully extend your arms straight out perpendicular to your body and face your palms forward (like you are taking an oath with two hands). In certain cases of severe encephalopathy or liver failure, the hands will start to 'flap' involuntarily.
I hope we are refering to the same thing.
I searched this one as well and got the same single result.
I didn't post it as I felt that someone who could post a coherent message couldn't have asterixis.
He didn't say he has it,just that he has heard the term of course.In any event it's a bit of a mystery.