Chronic pain

I just went to the California Assoc Nurse Anesthetists Spring meeting in Palm Springs. One of the lecturers was about pain management by Chuck Griffis (I think). He talked about NMDA receptors and the positive feedback of the pain cycle in chronic pain patients. Really detailed and more than you'd want to see here!
But, when I talked to my peers, I found many of the old school anesthetists add 15-25mg of ketamine to their propofol when they induce a patient. They say that it helps with stopping/slowing down the chronic pain cycle, and they wake up nicer since they don't have to use much versed, etc. Anyone else doing this? What are your reasons? Have you found the patients easy to wake up? (Of course not with eye cases!!)