management is a new field of study. Over the last decade many large

medical centers and some private institutions both nationally and

internationally have opened pain clinics or centers strictly for its

study. These centers and clinics generally focus on the chronic pain

patient. This study is about acute pain, and a good place to begin is by

reviewing the differences between chronic and acute pain. Identifying

the differences helps to explain why the two types of pain are not

studied together.

 Sternbach's (1978) review of the experimental and clinical literature

 reveals a significant difference between acute and chronic pain. Acute

 pain is described as "pain of recent onset or of short duration" (p.

 243). An example of this would be surgical pain. Chronic pain is "pain

 of at least several months duration" (p. 243). An example of this would

 be pain associated with chronic arthritis or recurrent migraine

 headaches.

 Besides temporality, the differences between these two types of pain

are both physiological and psychological. Table 1-1 lists the basic

differences in response to the two types of pain. Acute pain is

generally accompanied by an increase in the release of epinephrine,

causing many physiological symptoms. Investigators have found that

medical or psychological intervention to reduce anxiety associated with

acute pain will diminish the pain response. Likewise, treatment of the

depression associated with chronic pain "frequently results in a signifi-

cant reduction of pain," and "the reduction or abolition of pain reverses

the neurotic depression caused by the pain" (Sternbach, 1978, p. 243).