Pain Management Lecture 3 - PDF

# Chapter 5 Pain management and 'last offices' ## Classifying pain ### Background Pain is the commonest reason for patients to seek medical attention. The International Association for the Study of Pain has defined pain as 'an unpleasant sensory and emotional experience associated with actual or...

# Chapter 5 Pain management and 'last offices' ## Classifying pain ### Background Pain is the commonest reason for patients to seek medical attention. The International Association for the Study of Pain has defined pain as 'an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage'. It is a subjective experience that is influenced by physiological, psychological, social and cultural factors. The management of pain often requires a multi-professional and multifaceted approach, involving both pharmacological and non-pharmacological measures. It is important to identify and treat the underlying pathology, if possible. ### Classification of pain * Pain can be classified according its site, cause, type and chronicity. * There are 2 main types of pain: nociceptive and neuropathic. * Nociceptive pain is the reaction of the body to injury, such as trauma, surgery, or the inflammatory response. It can be classified as follows: * **Somatic** - which involves skin, muscle, or bone and is described as 'aching', 'throbbing', 'pressure', or 'stabbing'. * **Visceral** - which involves organs, is more difficult to pinpoint, and might be described as 'gnawing', 'cramping', 'aching', or 'sharp'. * Neuropathic pain is the result of injury to or malfunction of the peripheral or central nervous system. * The term **functional pain** is used when there is no obvious injury or pathological condition to account for the pain experienced. * **Acute** pain follows an injury to the body and usually dissipates when the injury heals. * Pain persisting for >3 months is categorized as **chronic**. It can be owing to a multitude of causes, including cancer and arthritis. Psychological factors can play a major role in chronic pain. ## Assessing pain ### Background The effective assessment of the patient with pain is essential for choosing the most appropriate intervention(s) to treat it. The system of assessment is similar for acute and chronic pain (LLD on p. 106 for definitions) although the urgency to initiate treatment is greater in acute pain. The assessment should be systematic and holistic, taking into account biological, psychological, cultural and social factors. ### Equipment * Pain scale * Usual equipment required for assessment of a patient including pen torch, thermometer, stethoscope and sphygmomanometer. ### Procedure * Take a history from the patient, including allergies, medications and the previous response to analgesia. * Characterize the pain using the following headings: * Onset * Location * Character * Duration * Frequency * Periodicity * Severity * Aggravating or relieving factors * Radiation * Use a pain scale to assess the severity of pain (on p. 108). * Review the patient's medical records. * Ask about associated symptoms, e.g. sweating. * Evaluate how the pain impacts on the patient's lifestyle. * Observe the patient - how are they moving? How are they holding the affected area? Are they guarding (protecting the affected area by holding it still)? Is there facial grimacing or wincing? * Perform a full or focused examination, as appropriate, to try and elicit the cause of the pain. ### Practice tips * Questionnaires can be useful for assessment of the impact of pain on the patient's life and activities of daily living. * Reassure the patient that taking analgesia will not interfere with your assessment of their pain. Patients often think that analgesia will mask their symptoms or signs and prevent the health care worker (HCW) elucidating the cause. ### Pitfalls * Not providing pain relief to a patient in severe pain before assessing them in depth. ## Use of pain scales ### Background The severity of pain can be assessed using verbal, visual, or numerical scales, which can be adapted to the patient's age or understanding. There are numerous pain scales, so it is important to choose one that is suitable for your area of work. A representative sample of rating scales for assessment of the intensity of pain is described below. ### Equipment * Pain scale ### Procedure * Choose a pain scale appropriate to the patient's age and level of understanding. * Explain the procedure and gain consent. ### Types of pain scale * **The Categorical Pain Scale** has four categories (none, mild, moderate, and severe). Ask the patient to select the category that best describes their pain. * **The Numerical Rating Scale** assigns a number to grades of pain, with 0 usually representing no pain and 10 representing the worst pain imaginable. Explain to the patient the meaning of the numbers and ask them to identify how much pain they are having by choosing a number from 0 to 10. * **The Visual Analogue Scale** is a straight line, with the left end of the line representing no pain and the right end representing the worst pain imaginable. Ask the patient to mark a point on the line where they think their pain is in relation to the two extremes. * **The Pain Faces Scale** uses four to six faces with different expressions, ranging from a happy face (representing no pain) to increasingly sad faces (representing pain of worsening severity). This scale can be used by people aged 3 years and older. Ask the patient to point to the face that best describes how they are feeling. * **The Face, Legs, Activity, Cry, Consolability (FLACC) Scale** is derived from observation of pre-verbal children. Numerical values are assigned to permutations of the various elements, which are then added up to give a severity score for pain. * **The Pain Ladder Scale** combines pain severity with the effect of pain on function. Ask the patient about the severity of the pain and what the pain prevents them from doing. * Document the episode of care, recording the level of pain and method of assessment used. * Repeat the procedure after administering analgesia, to assess its effect. ### Practice tips * Ensure that the patient is as relaxed as possible. Anxiety ↑ the patient's perception of pain. * One-off assessments of pain are performed most easily using the Categorical Pain Scale. A numerical value of pain is of little use as a one-off measurement. Numerical values or Visual Analogue Scales are useful, however, for sequential assessment (e.g. evaluation of the effects of treatments). * Ask the patient about pain at rest and on movement. A patient with a hip fracture might be pain-free while sitting on a trolley and then experience severe pain if moved for radiography or transfer. * Elderly people tend to be stoical and understate their pain. ### Pitfalls * Using pain scales in isolation from observation of the patient as a whole. It is unlikely that a person who self-scores 10 out of 10 for the severity of their pain and is sitting comfortably and chatting is truly experiencing pain of the worst severity. The reverse is also true, and patients can understate their pain when they are obviously in distress. * Not believing the patient's chosen place on the scale. It is easy to dismiss a patient's description of their pain intensity, particularly if no diagnosis has been found to explain it. All too often, patients with conditions such as cancer, fracture and compartment syndrome have been fobbed off as 'hysterical'. ## Pain Scales The document then contains numerous pain scales with visual and verbal illustrations. The scales are: | Scale | Description | |---|---| | Numerical pain scale | 0- 10 | | FLACC Scale | Assess children | | Pain Ladder Scale | Describes how pain severity affects function | | Visual Analogue Scale | Line of pain severity | | Face Rating Scale | Various facial expressions representing pain | | The Pain Faces Scale | Faces showing increasing pain |