The Royal Marsden Hospital Manual of Clinical Nursing Procedures - Lisa Dougherty [334]
Some degree of caution, however, must be exercised with the use of pain assessment tools. The nurse must be careful to select the tool that is most appropriate for a particular type of pain experience (Box 9.12). For example, it would not be appropriate to use a pain assessment tool that had been designed for use with patients with chronic pain to assess postoperative pain. Furthermore, pain tools should not be used totally indiscriminately. Walker et al. 1987 found that pain tools appeared to have little value in cases of unresolved or intractable pain.
Box 9.12 Most commonly used pain assessment tools
The most commonly used pain assessment tools meet the following criteria (Fitzpatrick et al. 1998).
Simplicity: ease of understanding for all patient groups.
Reliability: reliability of the tool when used in similar patient groups; results are reproducible and consistent.
Valid: the tool measures the patient’s perception of pain.
Sensitivity: sensitivity of the tool to the patient’s pain.
Accuracy: accurate and precise recording of data.
Interpretable: meaningful pain scores or data are produced.
Feasiblity/practicality: the degree of effort involved in using the tool is acceptable; a practical tool is more likely to be used by patients.
The use of pain assessment tools for acute pain has been shown both to increase the effectiveness of nursing interventions and to improve the management of pain (Harmer and Davies 1998, Scott 1994). Several pain assessment tools are available. Verbal descriptor scales (VDS) are based on numerically ranked words such as ‘none’, ‘mild’, ‘moderate’, ‘severe’ and ‘very severe’ for assessing both pain intensity and response to analgesia. Numerical rating scales (NRS) have both written and verbal forms. The written forms are either a vertical or a horizontal line with ‘0’, indicating no pain, located on one extremity of the line and ‘10’, indicating severe pain, at the other extremity. This type of scale is easily used as a verbal scale of 0–10 if patients are unable to see or focus on a written scale. Although originally published as a line with a scale of 0–10, there are many versions of it (Flaherty 1996). Since many of these scales focus on assessing the intensity of pain, it is important that nurses remember to combine their use of these tools with an assessment of the patient’s psychosocial needs.
For practical purposes, a combined pain assessment and observation chart is frequently used in the postoperative period. The Royal Marsden Hospital Postoperative Observation and Pain Assessment Chart is one example of these (Figure 9.10). The patient’s assessment of their pain is recorded on the numerical rating pain scale at the bottom of the chart at the same time that other observations are carried out (usually 2–4 hourly but more frequently if pain is not controlled).
Figure 9.10 The Royal Marsden Hospital NHS Foundation Trust Postoperative Observation and Pain Assessment Chart.
Other pain assessment tools have been developed to capture the multidimensional nature of pain. These specifically measure several features of the pain experience, including the location and intensity of pain, pattern of pain over time, the effect of pain on the patient’s daily function and activities, the effect on the patient’s mood and the ability to interact and socialize with others. Examples of these include the McGill Pain Questionnaire (MPQ) (Melzack 1975) and the Brief Pain Inventory (BPI) (Cleeland 1991). These are more commonly used in chronic pain assessment.
Neuropathic pain may require a specific assessment tool. Patients may describe spontaneous pain (arising without detectable stimulation) and evoked pain (abnormal responses to stimuli) (Bennett 2001). The Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) pain scale (Bennett 2001) was developed to more accurately assess this type of pain.
The Royal Marsden NHS Foundation Trust currently uses a patient-held pain tool for patients with chronic cancer pain (Figure 9.11).
Figure 9.11 The Royal Marsden