- To rationalise why pain needs to be assessed
- Describe the factors which influence pain assessment
- Discuss the process of assessing pain accurately taking into consideration the multidimensional influences on pain perception
Why assess pain?
Robust pain assessment is imperative to ensure that patients receive safe and effective pain management that is tailored to their needs. Pain assessment is fundamental in assisting the diagnosis of the cause of the pain and it should not be assumed that this is self evident. For example, one should not assume that in a post-operative patient a surgical wound is the source of pain experienced, it may be an uncomfortable cannula, a urinary catheter pulling or an unrelated pre-existing pain condition. Pain assessment is thus an integral part of the appropriate treatment and control of pain which drives pharmacotherapy. Pain should be regarded as the 5th vital sign to help raise awareness of the presence of pain and all healthcare professionals should routinely measure a person’s pain and then act on the information obtained.
Pain is a subjective, multifaceted experience that varies considerably between individuals. The same operation can produce different behavioural and physiological effects in different people. Pain experience is influenced by age, character, gender, social class, past experience, individual coping strategies, culture and appraisal of current circumstances. As an example a bad experience of poorly managed pain as a child will influence future experience. The appraisal of current circumstances can also be influential in many ways e.g. a patient who has had bad news broken to them about diagnosis or the uncertainty about outcome in the crisis of critical illness. Thus what one patient may describe as severe to them may be only mild to another patient. Similarly, the quality of pain, such as gnawing or stabbing, may mean different things to different patients making the assessment and measurement of pain even more complex.
The outcome of inadequate pain assessment and thus its subsequent management can be severe with significant physiological and psychological consequences (see Table 1). Increased postoperative morbidity, delayed recovery, a delayed return to normal daily living, and reduced patient satisfaction have all been reported . Furthermore poor postoperative pain management may lead to persistent pain after surgery . Consequently, inadequate pain management increases the use of health care resources and health care costs.
Unfortunately, some patients cannot tell us about their pain e.g the very young and the critically ill and physiological measures of pain e.g tachycardia and hypertension are not reliable because these measures can be confounded by other factors e.g sepsis and behavioural signs only indicate the presence of pain not location or intensity. Furthermore, there are several components to patient comfort and spiritual pain and well being which should be considered. Anxiety, particularly in the critically ill is common and poorly recognised. Also, acute confusional state in the critically ill may be due to sepsis, hypoxia or drug withdrawal and can be a confounding factor in the pain assessment process. In some patients particularly those who have undergone major surgery or experienced multiple trauma there are many different sources of pain. Pain can emanate from the surgical wound, trauma, joint pain secondary to immobilisation, endotracheal suctioning, insertion or removal of lines, traction and pulling on lines when moving or turning the patient.
Pain assessment enables the evaluation of treatment efficacy, helps to relieve suffering and avoid misconceptions. The principles of pain assessment include:
- Pain should be assessed at rest and on movement as the goal is to get the patient to mobilise early
- Pain assessment should be undertaken frequently at regular intervals with timings tailored to the severity of pain recorded, to assess the efficacy of the pain intervention and to observe the outcomes. This frequency can be reduced as the pain reduces.
- Pain assessment will evaluate how well the postoperative intervention is working
- Pain protocols within surgical wards should have pain scores defined at which treatment is offered
- Patients with communication problems (very young, patients with dementia, critically ill sedated patients, those unable to speak English) need to be assessed with bespoke postoperative assessment tools that are behavioural in nature
- Response to treatment needs to be recorded including side effects, complications and how these were managed.
- Clear documentation is important and should be accessible to all the team involved in the patients’ care
- Patients need to be educated about postoperative pain assessment and management, preoperatively if possible and this should include:
- Information about the importance of appropriate treatment
- Available pain treatment methods
- Pain assessment routines
- Patient participation in their own care
The description of painful experiences varies considerably. Consequently a range of adjectives that describe pain has arisen. However, the study of their meaning is relatively recent. Despite this abundance of words that describe pain; individuals still find it difficult to use these words. The main reason is that words such as gnawing, throbbing, shooting have few objective reference points, compared with the use of words like red or green, which although adjectives have definite reference to something we clearly understand .
- Joshi, G.P., Ogunnaike, B.O., 2005. Consequences of inadequate postoperative pain relief and chronic persistent postoperative pain.. Anesthesiol Clin North America, Anesthesiol Clin North America 23, 21-36.
- Macrae, W.A., 2001. Chronic pain after surgery.. Br J Anaesth, Br J Anaesth 87, 88-98.
- Turk, D.C., Melzack, R., Inc., N.L., 2001. Handbook of pain assessment.
- Wall, P.D., Melzack, R., 1999. Textbook of pain, 4thth ed. Churchill Livingstone, Edinburgh.