Assessment of Pain in Advanced Cancer Patients

Transcription

1 274 Journal of Pain and Symptom Management Vol. I0 No. 4 May 1995 Or/g/ha/Art/de Assessment of Pain in Advanced Cancer Patients Margaret M. Shannon, RN, Maureen A. Ryan, RN, Nancy D'Agostino, RN, and FrankJ. Brescia, MD Calvary Hospital, Bronx, New York Abstract This study tested the feasibility of standardized pain assessment instruments in a population of patients with far advanced cancer at the time of admission to a specialty hospital. As pain is a symptom, pain control must be based on patients' self-report. Cognitive impairment and severe physical illness, however, limited the ability to use these tools. Almost one-half (44.8%) of the patients were unable to use the McGiU-Melzack Pain Questionnaire, the Memorial Pain Assessment Card, or the Faces Pain Rating Scale. Patients with far advanced cancer fall into three groups: those who report pain, those who report no pain, and those who are unable to state whether or not they have pain. This study demonstrates the need to undertake pain assessment while the patient is able to respond and to monitor behaviors that could be indicative of changes in pain. J Pain Symptom Manage 1995;10: Key Words Pain measurement, neoplasms, terminal care, palliative care Introduction The principal goal in caring for dying patients is to minimize symptom distress and promote comfort. Pain is a symptom experienced by more than 70% of patients with advanced cancer. 1 Because pain is a subjective experience, effective pain management depends in large part upon self-report of pain. The purpose of the present study was to test the feasibility of standardized pain assessment tools in the population of dying patients admitted to Calvary Hospital, a specialty hospital that cares for patients with advanced cancer. An ideal pain-assessment tool should charac- Address reprint requests to: Margaret M. Shannon, RN, Clinical Review Department, Calvary Hospital, 1740 Eastchester Road, Bronx, NY 10461, USA. Accepted for publication: September 26, terize, describe, and differentiate various types of pain. The McGill-Melzack Pain Questionnaire (MPQ) measures both the physiologic and psychologic dimensions of pain and has been used in several studies of patients with cancer pain. 2-5 Other studies have shown that cancer pain intensity can be measured accurately with visual analogue and verbal categorical scales. 6-1 The present study assessed the value of these common instruments, and for comparison, also evaluated a tool that could potentially measure pain intensity in patients with reduced cognitive capacity, the Faces Pain Rating Scale. 11 Methods Patients admitted to Calvary Hospital were assessed on the third day of hospitalization. U.S. Cancer Pain Relief Committee, /95/$9.50 Published by Elsevier, New York, New York SSDI (95)00003-H

2 Vol. 10 No. 4 May 1995 Pain Assessment in Advanced Cancer 275 Level of awareness was assessed as follows: level 1, fully awake; level 2, less than fully awake but easily aroused by verbal or tactile stimuli; level 3, responsive to tactile stimuli but difficult to arouse; and level 4, unresponsive. Patients who were awake or easily aroused were questioned regarding the presence of pain; those who responded positively were asked to participate in the study. Those patients who were not experiencing pain at the time of the interview were asked to focus on the worst pain they had experienced since admission. Additional requirements for inclusion were adequate vision and hearing, and the ability to follow directions given in English. Assessment of patients who met these criteria included an evaluation of orientation, a brief pain history, and formal administration of the MPO~ the Memorial Pain Assessment Card (MPAC), and the Faces Pain Rating Scale. The specific measures were as follows: Orientation to Time and Place Orientation to time and place were tested using items taken from the Mini-Mental State Examination (MMSE). To determine orientation to time, the patient was asked to state the current season of the year, day of the week, and date. Orientation to place was elicited by asking the patient to describe his or her present location, i.e., the name of the hospital, the number of the floor, the name of the city or borough, the state, and the country. Brief Pain History Body drawings were shown to the patient, who was asked to indicate specific sites of pain. The patient was then asked to focus on the most recent pain and describe it as continuous, intermittent, or a combination of both. The patient was then asked to focus on this specific pain while completing the rest of the tools. McGill-Melzack Pain Questionnaire This study used the short form of the McGill-Melzack Pain Questionnaire. This instrument consists of 20 subclasses of word descriptors in three major classes--sensory, affective, and evaluative. The 20 subclasses of word descriptors were listed on a one-page form. The patient was asked to point to only one word in a subclass and to omit any subclass that was not suitable. If the patient was unable to read the words, the interviewer read each list, and the patient indicated any word that described his or her pain. Six MPQ scores were calculated. The rank values in each subclass were combined to yield pain rating indices (PRI) for each class--pri-s (sensory), PRI-A (affective), PRI-E (evaluative), and PRI-M (miscellaneous). The total pain rating index (PRI-T) was obtained by adding the rank values of the words selected by the patient from any of the subclasses. The sixth score is a simple count of the number of words chosen (NWC) from all subclasses. Memorial Pain Assessment Card The MPAC is composed of a visual analogue scale (MPAC 1) and a verbal descriptor scale (MPAC 2), which measure pain intensity, and visual analogue scales that measure pain relief (MPAC 3) and mood (MPAC 4). Each scale was presented to the patient separately. For the visual analogue scales, the patient placed a pencil mark on the 100-mm horizontal line at the location that represented his or her perception of pain intensity or relief. With the verbal descriptor scale, the patient was asked to indicate the word that best described his or her pain intensity. Faces Rating Scale The patient examined the illustrations of faces that express different moods (from happy to sad), and selected the one that expressed his or her pain intensity. The facial illustrations are given a range of scores from 1 for the smiling face to 5 for the crying face. Re~ Two hundred thirty-nine consecutively admitted patients were approached for participation in this study. Only 63 (26.4%) used the pain assessment tools. The principal reason for not participating was cognitive impairment (Table 1): 83 patients (34.7%) could not be aroused sufficiently or did not respond to questions. Adequate cognitive capacity for participation was defined as a score of less than 3 of a possible 5 on the orientation to place item of the MMSE. This screening test eliminated 15 more patients (6.3%) who had scores of less than 3, and five more (2.1%) who were not tested for orientation.

3 276 Shannon et al. Vol. 10 No. 4 May 1995 Table 1 Pain Assessment--Participant Selection N % N % Total population Nonparticipants Cognitive impairment Noncommunicative Disoriented to place Total No pain Communication barrier Other Severe physical illness Not tested for orientation Refused Total Participants Twenty-seven other patients (11.3%) were unable to use the tools because of communication barriers. This group included patients who were in respiratory isolation and those with language barriers, tracheostomies, aphasia, and hearing impairment. Nine patients (3.8%) were too ill to participate and two refused. Of the patients who could be assessed, 35 had no pain. The 63 patients who had pain and could use the pain assessment tools were compared with the 98 cognitively impaired patients who were unable to use them. The groups were similar in terms of sex, cancer diagnosis, and metastatic sites. There were, however, statistically significant differences in age and length of stay (Table 2). Participants were more likely to be in the "under 75" years age group, whereas the cognitively impaired patients were more likely to be in the "over 75" years age group. Patients in the cognitively impaired group also had shorter stays and, in most cases, were closer to death; 44.9% of the cognitively impaired group had a stay of 1-9 days compared to 11.1% of the participants. The proportions of participants and cognitively impaired patients who were given opioids on the day prior to the interview are compared on Table 3. It is perhaps significant that there was no statistically significant difference between the two groups in the amount of opioid drugs administered "as needed" only; those who were awake and able to verbally report pain received as many PRN opioids as those Table 2 Comparison According to Cognitive Capacity Participants Cognitively (intact) impaired N = 63 N = 98 N % N % Age Comparison Less than * and over * Length of stay comparison (days) ** "3( z = 7.60, df = 1, P< **Z 2 = 14.82, df= 1, P< who could not be aroused, did not respond to questions, or were disoriented. Forty percent of those who were cognitively impaired were receipting routinely administered opioids. These patients were either being maintained on a regimen that was started at a time when they were able to communicate or were exhibiting behavior that was assessed as indicating pain. Significantly more of the cognitively impaired received no opioids. There were small differences in the participants' ability to complete the MPO~ various scales on the MPAC, and the Faces Pain Rating Scale. The categorical scale on the MPAC could be used by 89% of the participants, while Table 3 Comparison of Opioid Use According to Patients' Cognitive Capacity Participants Nonparticipants Awake and Cognitively Oriented Impaired (N= 63) (N= 98) Opioid Schedule N % N % Routine and PRN Routine only PRN only * None ** Total PRN, as needed. *Z ~ = 1.98, df= 1, P< **Z 2 = 10.70, df= 1, P< 0.01.

4 Vol. 10 No. 4 May 1995 Pain Assessment in Advanced Cancer % completed the MPO_~ and the Faces Pain Rating Scale was completed by 81%. The visual analogue scales for pain intensity and mood included in the MPAC were completed by 75% of the participants, the fewest number to use a tool in the small subpopulation that was able to complete any of these measures. The MPQ scores displayed in Table 4 indicate that the responding patients have wide variation in the quality of their pain. The mean Pain Rating Index (PRI-T) was 21.8, with scores ranging from 3 to 48. Each constellation of words selected by a patient represents a multifaced pain experience. As the subject selects, at most, one word from every subclass, the score for the number of words chosen (NWC) also equals the number of subclasses chosen. Patients had relatively higher scores in the evaluative and affective classes than in the sensory' class. Forty-five participants (85%) selected words from the evaluative class; "unbearable" was selected most often, followed by "miserable." The words "exhausting" and "tiring" were chosen most often from the affective subclasses. On the Memorial Pain Assessment Card, the two measures of pain intensity, MPAC 1 and MPAC 2, were correlated at a significant level. More patients completed the verbal descriptor scale (MPAC 2) than any other scale. The Table 4 Scores--Pain Assessment Tools N Mean SD Range McGill Pain Questionnaire PRI-T 53* PR1-S PRI-A PRI-E PRI-M NWC Memorial Pain Assessment Card MPAC ** MPAC ** MPAC MPAC Faces Pain Rating Scale SD, standard deviation. *The MPQwas begun by 53 patients; one discontinued participation after selecting words from the Sensory Subclasses only. **r= 0.365, P< word, "moderate," was selected most often, followed by "excruciating," and then, "strong." D/seuss/on Accurate self-report of pain is crucial to pain management. Health-care providers who rely on their own observations of patients to assess pain often underestimate the intensity of pain. Grossman and colleagues 12 demonstrated this by having patients and their caregivers assess pain intensity using 10-cm visual analogue scales. There was no statistically significant correlation between the ratings for patients with a VAS greater than or equal to 4.0, that is, those who had moderate-to-severe pain. The present study shows that patients with far-advanced cancer fall into three groups: those who report no pain, those who report pain, and those who are unable to slate whether or not they have pain. Fifteen percent of the patients reported that they did not have pain, and 26% were able to describe the multidimensional aspects of their pain using standardized pain-assessment tools. The largest number of patients, however, were unable to use the standardized tools. There is no systematic way of assessing the pain experienced by this latter group. As the majority of cancer patients develop cognitive impairment near the end of life, ongoing pain assessment should be initiated as early as possible in the patient's course. The analgesic regimen that is established to control pain using the patient's verbal reports can be used to guide treatment when cognitive failure develops. A greater problem for caregivers occurs when a patient is already cognitively impaired on presentation and does not present behavioral signs of pain. Often, family members will report that the patient had been in pain previously, and they question whether or not he or she is currently in pain. Given the state of the art of pain assessment, the question cannot be answered with certainty. When a tool requires a level of cognition beyond the current capacity of the patient, or when caretakers use their own observations to determine the patient's level of pain, the assessments may not reflect the actual condition of the patient and may be

5 278 Shannon et al. Vol. 10 No. 4 May 1995 misleading. In either case, it is probable that analgesics will be administered inappropriately. Bruera and colleagues 1:~ studied assessment of pain intensity in patients with advanced cancer using a visual analogue scale (VAS). When patients experienced a cognitive failure episode, the tool was completed by the attending nurse. The 11 patients who showed evidence of agitation received more than twice as many "as needed" doses of an opioid as other patients. Upon recovery from the cognitive failure episode, none of the patients recalled having pain. The VAS completed by the nurse was significantly higher than the patient's assessment of pain intensity both before and after the cognitive failure episode. Eland 14 noted a study showing that 13 young children undergoing surgery received no analgesics, while 18 alert adults matched for diagnosis received 672 doses of analgesics. It is probable that the children were not given analgesics because they could not verbally express their pain. Cognitively impaired adults might be treated similarly to young children. In patients with advanced cancer, multidimensional pain assessment should be undertaken as early as possible and followed by ongoing monitoring so that changes in pain can be recognized and treated. As standardized pain-assessment tools for patients with at least a minimal level of cognitive capacity are available, self-report of pain should be the standard of care. Scales that measure behaviors indicative of negative emotional and/or physical states might substitute for verbal scales with cognitively impaired patients. Hurley and colleagues 15 developed such a scale for measuring discomfort in noncommunicative patients with advanced Alzheimer's disease. Development of behavioral assessment tools for pain assessment in cognitively impaired patients with far-advanced cancer should continue so that all patients receive appropriate pain-relief interventions. R ~f6q-6q/gd3$ 1. Brescia FJ, Portenoy RK, Ryan M, Krasnoff L, Gray G. Pain, opioid use, and survival in hospitalized patients with advanced cancer. J Clin Oncol 1992; 10: Melzack R. The McGill pain questionnaire: major properties and scoring methods. Pain 1975;1: Graham C, Bond SS, Gerkovich MM, Cook MR. Use of the McGill pain questionnaire in the assessment of cancer pain: replicability and consistency. Pain 1980;8: McGuire DB. Assessment of pain in cancer inpatients using the McGill pain questionnaire. Oncol Nurs Forum 1984;11: Zimmerman L, Duncan K, Pozehl B, Schmitz R. Pain descriptors used by patients with cancer. Oncol Nurs Forum 1987;14: Ahles TA, Ruckdeschel JC, Blanchard EB. Cancer-related pain. II. Assessment with visual analogue scales. J Psychosom Res 1984;28: StambaughJE, McAdamsJ. Comparison of verbal and visual analogue descriptors of analgesic efficacy of parenteral dezocine (Dalgan) to butorphanol and placebo in patients with chronic cancer pain. J Clin Pharmacol 1984;24: Littman GS, Walker BR, Schneider BE. Reassessment of verbal and visual analogue ratings in analgesic studies. Clin Pharmacol Ther 1985;38: Bond MR, Pilowsky I. Subjective assessment of pain and its relationship to the administration of analgesics in patients with advanced cancer. J Psychsom Res 1966;10: Fishman B, Pasternak S, Wallenstein SL, Houde RW, Holland JC, Foley KM. The Memorial pain assessment card. Cancer 1987;60: Whaley L, Wong D. Nursing care of infants and children, 3rd edition. St. Louis, Missouri: Mosby Year Book, 1987: Grossman SA, Sheidler VR, Swedeen K, Mucenski J, Piantadosi S. Correlation of patient and caregiver ratings of cancer pain. J Pain Symptom Manage 1991;6: Bruera E, Fainsinger RL, Miller MJ, Kuehn N. The assessment of pain intensity in patients with cognitive failure: a preliminary report. J Pain Symptom Manage 1992;7: ElandJM. Pain in children. Nurs Clin North Am 1990;25: Hurley AC, Volicer BJ, Hanrahan PA, Houde S, Volicer L. Assessment of discomfort in advanced Alzheimer patients. Res Nurs Health 1992;15: