- determine whether primary antineoplastic therapy is indicated for palliation
- tailor pharmacologic analgesic therapy to individual needs
- consider concurrent nonpharmacologic analgesic methods
- monitor response and modify treatment accordingly (Figure 1).
Pain history Begin with a thorough history. As there are no objective means with which to verify the presence of pain, one must believe a patient's complaint. The physiologic signs of acute pain-elevated blood pressure and pulse rate-are unreliable in subacute or chronic pain. Most cancer patients report more than one site of pain. A detailed history of each type of pain should be elicited (Table 1). As the chief complaint resolves, what was initially a secondary problem may require attention. Pain-rating scales should be used to establish a baseline against which the success of treatment may be judged (Figure 2). Behavioral observations may be used to assess patients who are unable to communicate. Although there are standardized tools for preverbal children, they are not available for impaired adults. Thus, it is sometimes necessary to treat pain presumptively. Physical examination includes careful neurologic testing, especially if neuropathic pain is suspected. Pain in an area of reduced sensation, allodynia (ie, when normal stimuli are reported as painful), and hyperpathia or summation of painful stimuli indicate a neuropathic process. The assessment should evaluate the putative mechanisms that may underlie the pain. Review of disease extent and current conditions The extent of disease and current medical conditions must be determined. Diagnostic tests should be reviewed and supplemented as necessary. Treatment and drug history Cancer treatment and prior analgesic interventions, along with their outcomes, should be recorded. Psychological dependency on any drug, including alcohol(Drug information on alcohol), must be identified. Psychosocial assessment
To establish trust, the evaluating clinician should explore with the patient the significance of the pain complaint. The impact of pain and other symptoms on functional status must be understood to establish treatment goals. Suffering may be attributable to many factors besides physical complaints. The clinician should ask about such psychological factors as financial worries, loss of independence, family problems, social isolation, and fear of death. Often, cancer patients meet diagnostic criteria for the psychiatric diagnosis of adjustment disorder with anxiety and/or depressed mood. Patient subgroups To help define therapeutic goals, the patient's age and prognosis may be considered. Adjustments in drug doses are usually needed for elderly patients, who are more sensitive to analgesics and their side effects. Adolescents may require relatively larger doses of opioids. Pain in children is underreported and should be specifically elicited using age-appropriate assessment tools.