A pain scale measures a patient's pain intensity or other features. Pain scales are a common communication tool in medical contexts, and are used in a variety of medical settings. Pain scales are a necessity to assist with better assessment of pain and patient screening. Pain measurements help determine the severity, type, and duration of the pain, and are used to make an accurate diagnosis, determine a treatment plan, and evaluate the effectiveness of treatment.[ medical citation needed ] Pain scales are based on trust, cartoons (behavioral), or imaginary data, and are available for neonates, infants, children, adolescents, adults, seniors, and persons whose communication is impaired. Pain assessments are often regarded as "the 5th vital sign". [1]
A patient's self-reported pain is so critical in the pain assessment method that it has been described as the "most valid measure" of pain. [2] [3] The focus on patient report of pain is an essential aspect of any pain scale, but there are additional features that should be included in a pain scale. In addition to focusing on the patient's perspective, a pain scale should also be free of bias, accurate and reliable, able to differentiate between pain and other undesired emotions, absolute not relative, and able to act as a predictor or screening tool. [2]
Pain is a complex experience with both sensory and emotional elements that typically indicates a potential issue in the nervous system. It alerts organisms to potential injuries and medical conditions that may require medical assistance. The sensation of pain is an unpleasant or discomforting feeling that can manifest as sensations such as pricking, tingling, burning, stinging, shooting, aching, or electric. Pain can vary in intensity, from very mild to very severe; duration, short-lived to chronic; and location, one localized area or all over the body. [4]
There are three different types of pain based on the duration of the sensations: acute, episodic, and chronic. The most common are acute and chronic. Acute pain occurs suddenly, is sharp, and goes away once the issue is treated. Acute pain is caused by things like broken bones, childbirth, strained muscles, or burns. [5] Episodic pain occurs irregularly from time to time. It may be caused by underlying medical conditions or it can come out of nowhere. [5] Chronic pain is pain that is consistent for at least 3 months. Acute pain can become chronic, however, there usually is no known cause for chronic pain. Chronic pain can have negative effects on relationships, daily living, work, extracurricular activities, etc. [5]
The experience of pain is extremely unique for an individual, as all people feel pain differently. As a result of this, self-reporting is the best and most common practice for describing pain to medical personnel. [5]
The practice of measuring pain has been a topic in research since the late 1800s. There were many methods used for assessing the intensity of pain, in humans as well as animals, using electrical, mechanical, and heat stimuli. Over time these methods have evolved; however, there were limitations to these historical methods. The limitations were in addressing the dimensions of pain duration, modality, locus, and response type. The main focus at the time was on acute pain rather than chronic pain. Researchers and clinicians are more interested in information on chronic pain due to its longevity. The locus of pain also differs between clinical and experimental settings; clinical pain is usually deeper while experimental pain is superficial. Furthermore, the response type to pain can contribute to further challenges for interpretation in both preclinical and clinical research. [6] [7]
The Dolorimeter, created in 1940 at Cornell University, was one of the first methods used to gather information on pain threshold and tolerance. The instrument applied steady pressure, heat, or electrical stimuli to measure sensations of pain. Beecher was one of the first to suggest something other than the dolorimeter; he suggested that clinical pain be measured by its relief using subjective ratings. Numerical rating scales (NRS), verbal rating scales (VRS), and visual analog scales (VAS) on a 10-cm continuum are the scales used to attain these ratings. Melzack and Torgerson developed the McGill Pain Questionnaire which rates pain quantitatively by sensory, evaluative, and affective descriptors. These are things like burning, shooting, and agonizing. [7]
There have been many methods developed that use observational techniques where pain is evaluated by others. Such a method, for example, is the FLACC scale. It is for young children who are too young to be able to tell anyone how they feel. It measures facial expressions, leg position, activity, crying, and concealability on a 0–2 scale. [7]
There are many different instruments used to assess both the intensity of pain as well as the effect of pain. A few are listed below:
The Numeric Rating Scale (NRS-11) is an 11-point scale for patient self-reporting of pain. It is based solely on the ability to perform activities of daily living (ADLs) and can be used for adults and children 10 years old or older. [8]
Rating | Pain Level |
---|---|
0 | No Pain |
1–3 | Mild Pain (nagging, annoying, interfering little with ADLs) |
4–6 | Moderate Pain (interferes significantly with ADLs) |
7–10 | Severe Pain (disabling; unable to perform ADLs) |
Pain interferes with a person's ability to perform ADLs. Pain also interferes with a person's ability to concentrate, and to think. A sufficiently strong pain can be disabling on a person's concentration and coherent thought, even though it is not strong enough to prevent that person's performance of ADLs. However, there is no system available for measuring concentration and thought.
The verbal rating scale (VRS) is a pain measurement tool that uses adjectives to express various levels of pain. The scale is rated similarly from no pain at all to the most extreme pain ever felt. When doing clinical trials there is usually a four-to six-point VRS. There are a few limitations to this scale. Some people might find it hard to accurately express their pain with the limited number of options to choose from. Interpretation of the options is also a potential issue, as people could interpret them all differently. [9]
The visual analog scale is a visual scale that has two endpoints: "no pain" and "pain is as bad as it could be". When it was first created people had to physically write their answers on the scale. There are mechanical ones now to make the scoring of them easier. [9]
Self-report | Observational | Physiological | |
---|---|---|---|
Infant | — | Premature Infant Pain Profile; Neonatal/Infant Pain Scale | — |
Child | Faces Pain Scale – Revised; [10] Wong-Baker FACES Pain Rating Scale; Coloured Analogue Scale [11] | FLACC (Face Legs Arms Cry Consolability Scale); CHEOPS (Children's Hospital of Eastern Ontario Pain Scale) [12] | Comfort; Wharton PAIN Scale |
Adult | Visual Analog Scale (VAS); Verbal Numerical Rating Scale (VNRS); Verbal Descriptor Scale (VDS); Brief Pain Inventory | Wharton Impairment and Pain Scale | Wharton PAIN Scale |
The most common pain scale for quantification of endometriosis-related pain is the visual analogue scale (VAS). A review came to the conclusion that VAS and numerical rating scale (NRS) were the best adapted pain scales for pain measurement in endometriosis. For research purposes, and for more detailed pain measurement in clinical practice, the review suggested use of VAS or NRS for each type of typical pain related to endometriosis (dysmenorrhea, deep dyspareunia and non-menstrual chronic pelvic pain), combined with the clinical global impression (CGI) and a quality of life scale. [17]
Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage."
Palliative care is an interdisciplinary medical caregiving approach aimed at optimizing quality of life and mitigating suffering among people with serious, complex, and often terminal illnesses. Within the published literature, many definitions of palliative care exist. The World Health Organization (WHO) describes palliative care as "an approach that improves the quality of life of patients and their families facing the problems associated with life-threatening illness, through the prevention and relief of suffering by means of early identification and impeccable assessment and treatment of pain, illnesses including other problems whether physical, psychosocial, and spiritual". In the past, palliative care was a disease specific approach, but today the WHO takes a broader patient-centered approach that suggests that the principles of palliative care should be applied as early as possible to any chronic and ultimately fatal illness. This shift was important because if a disease-oriented approach is followed, the needs and preferences of the patient are not fully met and aspects of care, such as pain, quality of life, and social support, as well as spiritual and emotional needs, fail to be addressed. Rather, a patient-centered model prioritizes relief of suffering and tailors care to increase the quality of life for terminally ill patients.
Pain management is an aspect of medicine and health care involving relief of pain in various dimensions, from acute and simple to chronic and challenging. Most physicians and other health professionals provide some pain control in the normal course of their practice, and for the more complex instances of pain, they also call on additional help from a specific medical specialty devoted to pain, which is called pain medicine.
Vital signs are a group of the four to six most crucial medical signs that indicate the status of the body's vital (life-sustaining) functions. These measurements are taken to help assess the general physical health of a person, give clues to possible diseases, and show progress toward recovery. The normal ranges for a person's vital signs vary with age, weight, sex, and overall health.
Nursing assessment is the gathering of information about a patient's physiological, psychological, sociological, and spiritual status by a licensed Registered Nurse. Nursing assessment is the first step in the nursing process. A section of the nursing assessment may be delegated to certified nurses aides. Vitals and EKG's may be delegated to certified nurses aides or nursing techs. It differs from a medical diagnosis. In some instances, the nursing assessment is very broad in scope and in other cases it may focus on one body system or mental health. Nursing assessment is used to identify current and future patient care needs. It incorporates the recognition of normal versus abnormal body physiology. Prompt recognition of pertinent changes along with the skill of critical thinking allows the nurse to identify and prioritize appropriate interventions. An assessment format may already be in place to be used at specific facilities and in specific circumstances.
A patient-reported outcome (PRO) is a health outcome directly reported by the patient who experienced it. It stands in contrast to an outcome reported by someone else, such as a physician-reported outcome, a nurse-reported outcome, and so on. PRO methods, such as questionnaires, are used in clinical trials or other clinical settings, to help better understand a treatment's efficacy or effectiveness. The use of digitized PROs, or electronic patient-reported outcomes (ePROs), is on the rise in today's health research setting.
Thiocolchicoside is a muscle relaxant with anti-inflammatory and analgesic effects. Its mechanism of action is unknown, but it is believed to be act via antagonism of nicotinic acetylcholine receptors (nAchRs). However, it also appears to be a competitive antagonist of GABAA and glycine receptors. As such, it has powerful convulsant activity and should not be used in seizure-prone individuals.
The Brief Pain Inventory is a medical questionnaire used to measure pain, developed by the Pain Research Group of the WHO Collaborating Centre for Symptom Evaluation in Cancer Care. The Brief Pain Inventory (BPI) is widely used around the world today to help with measuring a patients' pain intensity and the amount of interference the pain has on their being able to function in everyday life. BPI was originally intended to help measure cancer patients pain, but today it is used in cancer related cases as well as non-cancer related cases.
The visual analogue scale (VAS) is a psychometric response scale that can be used in questionnaires. It is a measurement instrument for subjective characteristics or attitudes that cannot be directly measured. When responding to a VAS item, respondents specify their level of agreement to a statement by indicating a position along a continuous line between two end points.
In general, quality of life is the perceived quality of an individual's daily life, that is, an assessment of their well-being or lack thereof. This includes all emotional, social and physical aspects of the individual's life. In health care, health-related quality of life (HRQoL) is an assessment of how the individual's well-being may be affected over time by a disease, disability or disorder.
An electronic patient-reported outcome (ePRO) is a patient-reported outcome that is collected by electronic methods. ePRO methods are most commonly used in clinical trials, but they are also used elsewhere in health care. As a function of the regulatory process, a majority of ePRO questionnaires undergo the linguistic validation process. When the data is captured for a clinical trial, the data is considered a form of Electronic Source Data.
The Patient Health Questionnaire (PHQ) is a multiple-choice self-report inventory that is used as a screening and diagnostic tool for mental health disorders of depression, anxiety, alcohol, eating, and somatoform disorders. It is the self-report version of the Primary Care Evaluation of Mental Disorders (PRIME-MD), a diagnostic tool developed in the mid-1990s by Pfizer Inc. The length of the original assessment limited its feasibility; consequently, a shorter version, consisting of 11 multi-part questions - the Patient Health Questionnaire was developed and validated.
The Oxford Hip Score (OHS) is a standard patient-reported outcome (PRO) measure, or PROM, developed to assess function and pain in patients undergoing total hip replacement (THR) surgery, particularly in the context of clinical trials. The OHS has also been used for the assessment of patient outcomes, including physical therapy, and use of joint supplements(disease specific and general health measure are two other outcome measures)
Catastrophic thinking has widely been recognized in the development and maintenance of hypochondriasis and anxiety disorders. This broadly accepted understanding has classified catastrophizing as a tendency to misinterpret and exaggerate situations that may be threatening. Pain is an undesirable sensory and emotional experience in response to potential or actual tissue damage. A general consensus of pain catastrophizing involves an exaggerated negative perception to painful stimuli. The components of catastrophizing that are considered primary were long under debate until the development of the Pain Catastrophizing Scale (PCS) by Michael J. L. Sullivan and Scott R. Bishop of Dalhousie University in 1995. The PCS is a 13 item scale, with each item rated on a 5-point scale: 0 to 4. The PCS is broken into three subscales being magnification, rumination, and helplessness. The scale was developed as a self-report measurement tool that provided a valid index of catastrophizing in clinical and non-clinical populations. The results of the initial development and validation studies, performed by Sullivan and Bishop, indicated that the PCS is a reliable and valid measurement tool for catastrophizing, according to Sullivan and Bishop. The high test-retest relationships concluded that individuals may possess enduring beliefs with regards to the threat value of painful stimuli. It was also found that from a clinical perspective, the PCS may be useful in identifying individuals that may be more susceptible to high distress responses from aversive medical procedures such as chemotherapy or surgery.
Chronic wound pain is a condition described as unremitting, disabling, and recalcitrant pain experienced by individuals with various types of chronic wounds. Chronic wounds such as venous leg ulcers, arterial ulcers, diabetic foot ulcers, pressure ulcers, and malignant wounds can have an enormous impact on an individual’s quality of life with pain being one of the most distressing symptoms.
EQ-5D is a standardised measure of health-related quality of life developed by the EuroQol Group to provide a simple, generic questionnaire for use in clinical and economic appraisal and population health surveys. EQ-5D assesses health status in terms of five dimensions of health and is considered a ‘generic’ questionnaire because these dimensions are not specific to any one patient group or health condition. EQ-5D can also be referred to as a patient-reported outcome (PRO) measure, because patients can complete the questionnaire themselves to provide information about their current health status and how this changes over time. ‘EQ-5D’ is not an abbreviation and is the correct term to use when referring to the instrument in general.
Pain management in children is the assessment and treatment of pain in infants and children.
Sarah Elizabeth Hewlett is an emeritus Professor of Rheumatology Nursing at the University of the West of England and expert on rheumatoid arthritis (RA). She was appointed an Officer of the Order of the British Empire in the 2019 Birthday Honours.
Carl L. von Baeyer is a Canadian psychologist, academic, and author. He is a professor emeritus of psychology at the University of Saskatchewan.