Pain management, pain medicine, pain control or algiatry, is a branch of medicine employing an interdisciplinary approach for easing the suffering and improving the quality of life of those living with chronic pain The typical pain management team includes medical practitioners, pharmacists, clinical psychologists, physiotherapists, occupational therapists, physician assistants, nurse practitioners, and clinical nurse specialists. The team may also include other mental health specialists and massage therapists. Pain sometimes resolves promptly once the underlying trauma or pathology has healed, and is treated by one practitioner, with drugs such as analgesics and (occasionally) anxiolytics. Effective management of chronic (long-term) pain, however, frequently requires the coordinated efforts of the management team.
Medicine treats injury and pathology to support and speed healing; and treats distressing symptoms such as pain to relieve suffering during treatment and healing. When a painful injury or pathology is resistant to treatment and persists, when pain persists after the injury or pathology has healed, and when medical science cannot identify the cause of pain, the task of medicine is to relieve suffering. Treatment approaches to chronic pain include pharmacological measures, such as analgesics, antidepressants and anticonvulsants, interventional procedures, physical therapy, physical exercise, application of ice and/or heat, and psychological measures, such as biofeedback and cognitive behavioral therapy.
Pain can have many causes and there are many possible treatments for it. In the nursing profession, one common definition of pain is any problem that is "whatever the experiencing person says it is, existing whenever the experiencing person says it does". Different sorts of pain management address different sorts of pain.
- How intense is the pain?
- How does the pain feel?
- Where is the pain?
- What, if anything, makes the pain lessen?
- When did the pain start?
A common difficulty in pain management is communication. People experiencing pain may have difficulty recognizing or describing what they feel and how intense it is. Health care providers and patients may have difficulty communicating with each other about how pain responds to treatments. There is a continuing risk in many types of pain management for the patient to take treatment which is less effective than needed or which causes other difficulty and side effects. Some treatments for pain can be harmful if overused. A goal of pain management for the patient and their health care provider to identify the amount of treatment which addresses the pain but which is not too much treatment.
Another problem with pain management is that pain is the body's natural way of communicating a problem. Pain is supposed to resolve as the body heals itself with time and pain management. Sometimes pain management covers a problem, and the patient might be less aware that they need treatment for a deeper problem.
Physical medicine and rehabilitation
Physical medicine and rehabilitation employs diverse physical techniques such as thermal agents and electrotherapy, as well as therapeutic exercise and behavioral therapy, alone or in tandem with interventional techniques and conventional pharmacotherapy to treat pain, usually as part of an interdisciplinary or multidisciplinary program.
Transcutaneous electrical nerve stimulation has been found to be ineffective for lower back pain, however, it might help with diabetic neuropathy. Although there has not been adequate evidence based research on acute sensory TENS, chronic conditions are efficacious in relieving pain. TENS is indicated for any chronic musculoskeletal condition under the gate control theory of pain. Essentially, the gate control theory states that sensory fibers carry their signal faster than pain fibers, and thus make their way to the dorsal root ganglion of the spine (the gate) much faster. This in turn causes the pain signal to be blocked by the sensory TENS signal. This theory explains why rubbing a stubbed toe relieves pain. A study conducted by Oncel M and team compared the efficacy of TENS with a non-steroidal anti-inflammatory drug (NSAID, Naproxen sodium) in patients who had patients with uncomplicated minor rib fractures. The researchers found that TENS therapy given twice a day for 3 days resulted in significant pain reduction and was found to be more effective than NSAID or placebo.
Acupuncture involves the insertion and manipulation of needles into specific points on the body to relieve pain or for therapeutic purposes. An analysis of the 13 highest quality studies of pain treatment with acupuncture, published in January 2009 in the British Medical Journal, was unable to quantify the difference in the effect on pain of real, sham and no acupuncture.
Acupuncture is believed to restore the energy balance in the body through stimulation of energy channels called the meridians. It is believed acupuncture therapy reduces pain signals through production of endorphins that are known to be the natural painkillers. Clinical studies suggest that acupuncture can reduce joint pain and so the therapy can be effective in reducing pain caused by knee osteoarthritis.
Interventional procedures - typically used for chronic back pain - include epidural steroid injections, facet joint injections, neurolytic blocks, spinal cord stimulators and intrathecal drug delivery system implants.
Pulsed radiofrequency, neuromodulation, direct introduction of medication and nerve ablation may be used to target either the tissue structures and organ/systems responsible for persistent nociception or the nociceptors from the structures implicated as the source of chronic pain.
An intrathecal pump used to deliver very small quantities of medications directly to the spinal fluid. This is similar to epidural infusions used in labour and postoperatively. The major differences are that it is much more common for the drug to be delivered into the spinal fluid (intrathecal) rather than epidurally, and the pump can be fully implanted under the skin. Interestingly, it is suggested this approach allows a smaller dose of the drug to be delivered directly to the site of action, with fewer systemic side effects, which is thus therapeutically questionable due to the fact that the three main opioid receptors; chiefly the [μ-,Қ-,and δ (Mu-,Kappa-, and Delta- respectively] are limited in their anatomical locations. The 3 main receptors are found dominantly within the brain, CNS and Digestive tract.
A spinal cord stimulator is an implantable medical device that creates electric impulses and applies them near the dorsal surface of the spinal cord provides a paresthesia ("tingling") sensation that alters the perception of pain by the patient.
A small number of patients, especially those with severe pain from untreatable cancer, may benefit surgical treatment such as cordotomy.
Cognitive behavioral therapy
Cognitive behavioral therapy (CBT) for pain helps patients with pain to understand the relationship between one's physiology (e.g., pain and muscle tension), thoughts, emotions, and behaviors. A main goal in treatment is cognitive restructuring to encourage helpful thought patterns, targeting a behavioral activation of healthy activities such as regular exercise and pacing. Lifestyle changes are also trained to improve sleep patterns and to develop better coping skills for pain and other stressors using various techniques (e.g., relaxation, diaphragmatic breathing, and even biofeedback).
Studies have demonstrated the usefulness of cognitive behavioral therapy in the management of chronic low back pain, producing significant decreases in physical and psychosocial disability. A study published in the January 2012 issue of the Archives of Internal Medicine found CBT is significantly more effective than standard care in treatment of people with body-wide pain, like fibromyalgia. Evidence for the usefulness of CBT in the management of adult chronic pain is generally poorly understood, due partly to the proliferation of techniques of doubtful quality, and the poor quality of reporting in clinical trials. The crucial content of individual interventions has not been isolated and the important contextual elements, such as therapist training and development of treatment manuals, have not been determined. The widely varying nature of the resulting data makes useful systematic review and meta-analysis within the field very difficult.
In 2009 a systematic review of randomized controlled trials (RCTs) of psychological therapies for the management of adult chronic pain (excluding headache) found that "CBT and BT have weak effects in improving pain. CBT and BT [behavior therapy] have minimal effects on disability associated with chronic pain. CBT and BT are effective in altering mood outcomes, and there is some evidence that these changes are maintained at six months;" and a review of RCTs of psychological therapies for the management of chronic and recurrent pain in children and adolescents, by the same authors, found "Psychological treatments are effective in pain control for children with headache and benefits appear to be maintained. Psychological treatments may also improve pain control for children with musculoskeletal and recurrent abdominal pain. There is some evidence available to estimate effects on disability or mood."
A 2007 review of 13 studies found evidence for the efficacy of hypnosis in the reduction of pain in some conditions, though the number of patients enrolled in the studies was small, bringing up issues of power to detect group differences, and most lacked credible controls for placebo and/or expectation. The authors concluded that "although the findings provide support for the general applicability of hypnosis in the treatment of chronic pain, considerably more research will be needed to fully determine the effects of hypnosis for different chronic-pain conditions.":283
Hypnosis has reduced the pain of some noxious medical procedures in children and adolescents, and in clinical trials addressing other patient groups it has significantly reduced pain compared to no treatment or some other non-hypnotic interventions. However, no studies have compared hypnosis to a convincing placebo, so the pain reduction may be due to patient expectation (the "placebo effect"). The effects of self hypnosis on chronic pain are roughly comparable to those of progressive muscle relaxation.
A meta-analysis of studies that used techniques centered around the concept of mindfulness, concluded, "Findings suggest that MBIs decrease the intensity of pain for chronic pain patients."
The World Health Organization (WHO) recommends a pain ladder for managing analgesia. It was first described for use in cancer pain, but it can be used by medical professionals as a general principle when dealing with analgesia for any type of pain. In the treatment of chronic pain, whether due to malignant or benign processes, the three-step WHO Analgesic Ladder provides guidelines for selecting the kind and stepping up the amount of analgesia. The exact medications recommended will vary with the country and the individual treatment center, but the following gives an example of the WHO approach to treating chronic pain with medications. If, at any point, treatment fails to provide adequate pain relief, then the doctor and patient move onto the next step.
|Common types of pain and typical drug management|
|Pain type||typical initial drug treatment||comments|
|headache||paracetamol /acetaminophen, NSAIDs||doctor consultation is appropriate if headaches are severe, persistent, accompanied by fever, vomiting, or speech or balance problems; self-medication should be limited to two weeks|
|migraine||paracetamol, NSAIDs||triptans are used when the others do not work, or when migraines are frequent or severe|
|menstrual cramps||NSAIDs||some NSAIDs are marketed for cramps, but any NSAID would work|
|minor trauma, such as a bruise, abrasions, sprain||paracetamol, NSAIDs||opioids not recommended|
|severe trauma, such as a wound, burn, bone fracture, or severe sprain||opioids||more than two weeks of pain requiring opioid treatment is unusual|
|strain or pulled muscle||NSAIDs, muscle relaxants||if inflammation is involved, NSAIDs may work better; short-term use only|
|minor pain after surgery||paracetamol, NSAIDs||opioids rarely needed|
|severe pain after surgery||opioids||combinations of opioids may be prescribed if pain is severe|
|muscle ache||paracetamol, NSAIDs||if inflammation involved, NSAIDs may work better.|
|toothache or pain from dental procedures||paracetamol, NSAIDs||this should be short term use; opioids may be necessary for severe pain|
|kidney stone pain||paracetamol, NSAIDs, opioids||opioids usually needed if pain is severe.|
|pain due to heartburn or gastroesophageal reflux disease||antacid, H2 antagonist, proton-pump inhibitor||heartburn lasting more than a week requires medical attention; aspirin and NSAIDs should be avoided|
|chronic back pain||paracetamol, NSAIDs||opioids may be necessary if other drugs do not control pain and pain is persistent|
|osteoarthritis pain||paracetamol, NSAIDs||medical attention is recommended if pain persists.|
|fibromyalgia||antidepressant, anticonvulsant||evidence suggests that opioids are not effective in treating fibromyalgia|
Mild to moderate pain
Paracetamol, an NSAID and/or paracetamol in a combination product with a weak opioid such as tramadol, may provide greater relief than their separate use. Also a combination of opioid with acetaminophen can be frequently used such as Percocet, Vicodin, or Norco.
Moderate to severe pain
When treating moderate to severe pain, the type of the pain, acute or chronic, needs to be considered. The type of pain can result in different medications being prescribed. Certain medications may work better for acute pain, others for chronic pain, and some may work equally well on both. Acute pain medication is for rapid onset of pain such as from an inflicted trauma or to treat post-operative pain. Chronic pain medication is for alleviating long-lasting, ongoing pain.
Morphine is the gold standard to which all narcotics are compared. Semi-synthetic derivatives of morphine such as hydromorphone (Dilaudid), oxymorphone (Numorphan, Opana), nicomorphine (Vilan), hydromorphinol and others vary in such ways as duration of action, side effect profile and milligramme potency. Fentanyl has the benefit of less histamine release and thus fewer side effects. It can also be administered via transdermal patch which is convenient for chronic pain management. In addition to the intrathecal patch and injectable Sublimaze, the FDA has approved various immediate release fentanyl products for breakthrough cancer pain (Actiq/OTFC/Fentora/Onsolis/Subsys/Lazanda/Abstral). Oxycodone is used across the Americas and Europe for relief of serious chronic pain; its main slow-release formula is known as OxyContin, and short-acting tablets, capsules, syrups and ampules are available making it suitable for acute intractable pain or breakthrough pain. Diamorphine, methadone and buprenorphine are used less frequently. Pethidine, known in North America as meperidine, is not recommended for pain management due to its low potency, short duration of action, and toxicity associated with repeated use. Pentazocine, dextromoramide and dipipanone are also not recommended in new patients except for acute pain where other analgesics are not tolerated or are inappropriate, for pharmacological and misuse-related reasons. In some countries potent synthetics such as piritramide and ketobemidone are used for severe pain, and tapentadol is a newer agent introduced in the last decade.
Drugs of other types can be used to help opioids combat certain types of pain, for example, amitriptyline is prescribed for chronic muscular pain in the arms, legs, neck and lower back with an opiate, or sometimes without it and/or with an NSAID.
From the Food and Drug Administration's website: "According to the National Institutes of Health, studies have shown that properly managed medical use of opioid analgesic compounds (taken exactly as prescribed) is safe, can manage pain effectively, and rarely causes addiction."
Opioid medications can provide short, intermediate or long acting analgesia depending upon the specific properties of the medication and whether it is formulated as an extended release drug. Opioid medications may be administered orally, by injection, via nasal mucosa or oral mucosa, rectally, transdermally, intravenously, epidurally and intrathecally. In chronic pain conditions that are opioid responsive a combination of a long-acting (OxyContin, MS Contin, Opana ER, Exalgo and Methadone) or extended release medication is often prescribed in conjunction with a shorter-acting medication (oxycodone, morphine or hydromorphone) for breakthrough pain, or exacerbations.
Most opioid treatment used by patients outside of healthcare settings is oral (tablet, capsule or liquid), but suppositories and skin patches can be prescribed. An opioid injection is rarely needed for patients with chronic pain.
Although opioids are strong analgesics, they do not provide complete analgesia regardless of whether the pain is acute or chronic in origin. Opioids are efficacious analgesics in chronic malignant pain and modestly effective in nonmalignant pain management. However, there are associated adverse effects, especially during the commencement or change in dose. When opioids are used for prolonged periods drug tolerance, chemical dependency, diversion and addiction may occur.
Clinical guidelines for prescribing opioids for chronic pain have been issued by the American Pain Society and the American Academy of Pain Medicine. Included in these guidelines is the importance of assessing the patient for the risk of substance abuse, misuse, or addiction; a personal or family history of substance abuse is the strongest predictor of aberrant drug-taking behavior. Physicians who prescribe opioids should integrate this treatment with any psychotherapeutic intervention the patient may be receiving. The guidelines also recommend monitoring not only the pain but also the level of functioning and the achievement of therapeutic goals. The prescribing physician should be suspicious of abuse when a patient reports a reduction in pain but has no accompanying improvement in function or progress in achieving identified goals.
Commonly-used long-acting opioids and their parent compound:
- OxyContin (oxycodone)
- Hydromorph Contin (hydromorphone)
- MS Contin (morphine)
- M-Eslon (morphine)
- Exalgo (hydromorphone)
- Opana ER (oxymorphone)
- Duragesic (fentanyl)
- Nucynta ER (tapentadol)
- Metadol/Methadose (methadone)*
- Hysingla ER (hydrocodone bitartrate)
- Zohydro ER (hydrocodone bicarbonate)
*Methadone can be used for either treatment of opioid addiction/detoxification when taken once daily or as a pain medication usually administered on an every 12-hour or 8-hour dosing interval.
Non-steroidal anti-inflammatory drugs
The other major group of analgesics are non-steroidal anti-inflammatory drugs (NSAID). Acetaminophen/paracetamol is not always included in this class of medications. However, acetaminophen may be administered as a single medication or in combination with other analgesics (both NSAIDs and opioids). The alternatively prescribed NSAIDs such as ketoprofen and piroxicam have limited benefit in chronic pain disorders and with long-term use are associated with significant adverse effects. The use of selective NSAIDs designated as selective COX-2 inhibitors have significant cardiovascular and cerebrovascular risks which have limited their utilization.
Antidepressants and antiepileptic drugs
Some antidepressant and antiepileptic drugs are used in chronic pain management and act primarily within the pain pathways of the central nervous system, though peripheral mechanisms have been attributed as well. These mechanisms vary and in general are more effective in neuropathic pain disorders as well as complex regional pain syndrome. Drugs such as gabapentin have been widely prescribed for the off-label use of pain control. The list of side effects for these classes of drugs are typically much longer than opiate or NSAID treatments for chronic pain, and many antiepileptics cannot be suddenly stopped without the risk of seizure.
Chronic pain is one of the most commonly cited reasons for the use of medical marijuana. A 2012 Canadian survey of participants in their medical marijuana program found that 84% of respondents reported using medical marijuana for the management of pain.
Evidence of medical marijuana's pain mitigating effects is generally conclusive. Detailed in a 1999 report by The Institute of Medicine, "the available evidence from animal and human studies indicates that cannabinoids can have a substantial analgesic effect." In a 2013 review study published in Fundamental & Clinical Pharmacology, various studies were cited in demonstrating that cannabinoids exhibit comparable effectiveness to opioids in models of acute pain and even greater effectiveness in models of chronic pain.
Other drugs are often used to help analgesics combat various types of pain, and parts of the overall pain experience, and are hence called adjuvant medications. Gabapentin — an anti-epileptic — not only exerts effects alone on neuropathic pain, but can potentiate opiates. While perhaps not prescribed as such, other drugs such as Tagamet (cimetidine) and even simple grapefruit juice may also potentiate opiates, by inhibiting CYP450 enzymes in the liver, thereby slowing metabolism of the drug. In addition, orphenadrine, cyclobenzaprine, trazodone and other drugs with anticholinergic properties are useful in conjunction with opioids for neuropathic pain. Orphenadrine and cyclobenzaprine are also muscle relaxants, and therefore particularly useful in painful musculoskeletal conditions. Clonidine has found use as an analgesic for this same purpose, and all of the mentioned drugs potentiate the effects of opioids overall.
Society and culture
Consensus in evidence-based medicine and the recommendations of medical specialty organizations establish the guidelines which determine the treatment for pain which health care providers ought to offer. For various social reasons, persons in pain may not seek or may not be able to access treatment for their pain. At the same time, health care providers may not provide the treatment which authorities recommend.
Acute pain is common in children and adolescents as a result of injury, illness, or necessary medical procedures. Chronic pain is present in approximately 15–25% of children and adolescents, and may be caused by an underlying disease, such as sickle cell anemia, cystic fibrosis, rheumatoid arthritis, or cancer or by functional disorders such as migraines, fibromyalgia, or complex regional pain.
Pain assessment in children is often challenging due to limitations in developmental level, cognitive ability, or their previous pain experiences. Clinicians must observe physiological and behavioral cues exhibited by the child to make an assessment. Self-report, if possible, is the most accurate measure of pain; self-report pain scales developed for young children involve matching their pain intensity to photographs of other children's faces, such as the Oucher Scale, pointing to schematics of faces showing different pain levels, or pointing out the location of pain on a body outline. Questionnaires for older children and adolescents include the Varni-Thompson Pediatric Pain Questionnaire (PPQ) and the Children’s Comprehensive Pain Questionnaire, which are often utilized for individuals with chronic or persistent pain.
Caregivers may provide nonpharmacological treatment for children and adolescents because it carries minimal risk and is cost effective compared to pharmacological treatment. Nonpharmacologic interventions vary by age and developmental factors. Physical interventions to ease pain in infants include swaddling, rocking, or sucrose via a pacifier, whereas those for children and adolescents include hot or cold application, massage, or acupuncture. Cognitive behavioral therapy (CBT) aims to reduce the emotional distress and improve the daily functioning of school-aged children and adolescents with pain through focus on changing the relationship between their thoughts and emotions in addition to teaching them adaptive coping strategies. Integrated interventions in CBT include relaxation technique, mindfulness, biofeedback, and acceptance (in the case of chronic pain). Many therapists will hold sessions for caregivers to provide them with effective management strategies.
Acetaminophen, nonsteroidal anti-inflammatory agents, and opioid analgesics are commonly used to treat acute or chronic pain symptoms in children and adolescents, but a pediatrician should be consulted before administering any medication.
Pain management practitioners come from all fields of medicine. In addition to medical practitioners, a pain management team may often benefit from the input of pharmacists, physiotherapists, clinical psychologists and occupational therapists, among others. Together the multidisciplinary team can help create a package of care suitable to the patient.
Pain physicians are often fellowship-trained board-certified anesthesiologists, neurologists, physiatrists or psychiatrists. Palliative care doctors are also specialists in pain management. The American Board of Anesthesiology, the American Osteopathic Board of Anesthesiology (recognized by the AOABOS), the American Board of Physical Medicine and Rehabilitation, and the American Board of Psychiatry and Neurology each provide certification for a subspecialty in pain management following fellowship training which is recognized by the American Board of Medical Specialties (ABMS) or the American Osteopathic Association Bureau of Osteopathic Specialists (AOABOS). As the field of pain medicine has grown rapidly, many practitioners have entered the field, some non-ACGME board-certified.
- Pain ladder
- Opioid comparison, an example of an equianalgesic chart
- Pain Catastrophizing Scale
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