UI - 000071

AU - Ellis JS Jr.

AU - Ramamurthy S

AU - Schoenfeld LS

AU - Hoffman J

AU - Walsh NE

TI - Diagnostic epidural opioid technique

AB - Diagnostic epidural blocks were performed on 27 chronic pain patients sequentially using saline,

fentanyl, and lidocaine solution. The patients were divided into one of four groups based on their response

to the epidural solutions: placebo response group--pain relief with placebo solutions; fentanyl response

group--pain relief with epidural fentanyl; lidocaine response group (LRG)--pain relief with lidocaine but not

fentanyl; and no response group--no pain relief with any of the solutions used. The four groups were

compared on the basis of age, sex, site of pain, duration of pain, narcotic use, pain assessment index, and

workmen's compensation claims. The comparisons resulted in the conclusion that LRG patients had a much

longer average duration of pain than the other groups. On the basis of the information gathered, it was

theorized that, despite their response to epidural lidocaine, LRG patients may actually be a group of operant

pain patients. Their failure to receive analgesia from epidural fentanyl may be a learned response such that

they associate any sensory input from the affected area as painful. If follow-up studies support these

findings, then the diagnostic opioid technique may be a more sensitive tool in diagnosing chronic pain

SO - Clinical Journal of Pain 1989;5:211-21