SGPT & SGOT Blood Tests

I have Reflex Sympathetic Dystrophy of the upper and lower extremities.  I am on Oxycontin 240mg, BID and Darvocet-N 100mg q6hrs, for pain.  I also take an aspirin 325mg qday for a MI I had in 2001. I have been on the Oxcontin 240mg for approximately 9-10 years, why would my doctor order an SGPT and an SGOT after all this time?  
I am also a diabetic, Type 2, and take oral medication for that, Metformin 1000mg daily and ctos 15mg daily.  I also take Lyrica 150mg BID and Baclofen 20mg TID, Lipitor 20mg qevening,  Lofibra 200 daily,  Synthroid 150mg qAM, I take other medications on a daily basis, but those are the main ones.  
Woulld these tests be able to tell how many Oxycontin's I take a day, or if I am taking more than I should?  I don't care if that's why my doctor is doing it, because I take all my medications as perscribed, I'm on too many to fool around with them.      Thank you.   Smokey481

[SassyLassie]

He is testing for liver function and liver enzymes in the blood.

An initial step in detecting liver damage is a simple blood test to determine the presence of certain liver enzymes in the blood. Under normal circumstances, these enzymes reside within the cells of the liver. But when the liver is injured for any reason, these enzymes are spilled into the blood stream. Enzymes are proteins that are present throughout the body, each with a unique function. Enzymes help to speed up (catalyze) routine and necessary chemical reactions in the body.

Among the most sensitive and widely used of these liver enzymes are the aminotransferases. They include aspartate aminotransferase (AST or SGOT) and alanine aminotransferase (ALT or SGPT). These enzymes are normally contained within liver cells. If the liver is injured, the liver cells spill the enzymes into blood, raising the enzyme levels in the blood and signaling the liver damage

It seems the doctor has waited a long time to do these, but, maybe he feels it is time to see if the dosages needs to be changed and just how well your liver is working while you have been on them for this length of time.