What Is Pain Management?
Table of Contents
- 1 What Is Pain Management?
- 2 What Is Chronic Pain?
- 3 The Mechanisms Of Chronic Pain
- 4 Other Factors That Affect Chronic Pain
- 5 Conditions Related To Chronic Pain Management
- 6 Pain Assessment And Its Role In Comprehensive Pain Management
- 7 Comprehensive Pain Management Strategies
- 8 Pharmacologic Approaches
- 9 Interventional Pain Management Or Alternative Strategies
- 10 Conclusion
- 11 References
Pain management programs may involve cooperation between many health professionals and specialists working on the same case. This is known as the interdisciplinary approach to comprehensive pain management. This may involve agreement between these parties and the patient on the best therapies or treatment methods that may be applied to a particular case. Optimal pain management plans are often also dependent on the underlying condition associated with pain, and the type of pain concerned.
A panel of different healthcare professionals and other practitioners typically collaborates to deliver a pain management plan. This team may include pain specialists, mental health professionals, physical therapists, occupational therapists, other or alternative practitioners, and nursing professionals. This team may contribute to the diagnosis or subsequent treatment of the case of pain in question. Treatments using this comprehensive pain management approach may involve one or more options that will be discussed in more detail below.
What Is Chronic Pain?Pain is the result of information-processing in the brain, which should result as an output. This is the perception of pain in reaction to noxious (harmful) stimuli. It also results in psychomotor and psychological reactions to this type of stimulus. However, malfunctions in the nervous tissue that conducts noxious stimulation to the brain may result in pain that is disproportional to the stimulus, or persists beyond reasonable expectations of recovery from it. This is the basis for many chronic pain conditions.
Pain that persists for three months or more satisfies the National Institutes of Health criteria for definition as chronic pain. However, this timeframe may be longer or shorter depending on specific conditions associated with cases of pain. Chronic pain is currently regarded as a serious healthcare and socioeconomic issue. The Centers for Disease Control and Prevention reported that up to 85% of all adults will be subject to some type of back pain (acute or chronic) during at least one point in their lifetime. According to the Institute of Medicine, chronic back pain is present in approximately 116 million people in the United States.
Nearly all human beings experience pain. However, this is a highly subjective experience, i.e. the sensations of pain resulting from the same condition may be described differently by different individuals. This renders the measurement and recording of painful experiences difficult. This fact is particularly challenging for those employed in pain research and pain management science. Some people may find it excessively difficult to cope with and function in the presence of pain, whereas others may not have this difficulty. Therefore, doctors need to assess reports of pain from patients carefully and design management plans for each individual carefully. The goal of this is to effectively and robustly relieve pain, and reduce its impact on everyday life for each patient.
Pain and painful conditions may have significant psychological and physiological effects if left untreated in the long term. Pain can affect many normal activities and functions such as the ability to eat or sleep. It may result in motor and functional impairments in some advanced cases. Some research suggests that chronic pain also has a negative effect on cognitive, attentional, and mnemonic functions. The psychological effects of pain may include increased feelings of helplessness, depressive symptoms, anxiety, fear, reduced coping skills or capacity, and thoughts of suicide in serious cases. Doctors and pain specialists should not ignore these symptoms when treating a case of chronic pain.
The Mechanisms Of Chronic PainPain may originate from injury or dysfunctions in the pain receptors on the sensory nerves in the body. Alternatively, other biochemical or even psychiatric disorders may contribute to a case of pain. The knowledge of and further investigation into these mechanisms is a vital component of pain management. The perception and processing of pain signals are complex mechanisms that involve nerves that run throughout the body from a point of origin in the central nervous system (the brain and spinal cord). Pain may be associated with damage or disorders in this nervous tissue.
The sensation of pain is initiated when tissue damage results in the activation of pain receptors, which sends this information to the brain. Pain receptors are also known as nociceptors. This tissue damage may result in injuries or trauma to the body, often associated with an environmental factor. This is also known as visceral or somatic pain. This type of pain may be categorized into deep somatic or cutaneous pain. Cutaneous (or superficial) pain is associated with the skin or with tissues just under the skin, and deep somatic pain is associated with tissues such as the bones, fascia, blood vessels, and nerves. Visceral pain relates to the noxious stimulation of receptors in the abdominal cavity (or thorax). On the other hand, some cases of pain are not related to the types of damage as above. This may be categorized as idiopathic or psychogenic pain.
Pain signals from these (peripheral) nerves is sent or conducted to a part of the brain known as the cerebral cortex. A subdivision of this, called the somatosensory cortex, analyzes the signal in terms of location and intensity. Pain signaling may be said to begin in the spinal cord, or rather the specific region of the spinal cord that is responsible for the area of the body affected by the noxious stimulus in question. Pain signals are picked up by the dorsal horn (a portion of the spinal cord located more toward the front of the body) region of the cord, which is where nociceptors are located. When activated, neurons (nerve cells) carrying these receptors activate other spinal cord neurons, which then activate other neurons closer to the brain, and so on, until the signal reaches the cerebral cortex.
The nerve cells that transmit noxious stimuli from the body area in question are mostly long, thin cells that form “bundles” not dissimilar from the thin wires that form a single fiber-optic cable. These are also known as fibers, and are divided into two general categories.
Fast fibers, or A-fibers, carry signals very quickly, which often translates to the perception of very sharp acute pain in the brain. Slow fibers, or C-fibers, conduct more widespread, burning, and more persistent pain. A-fiber signaling may be used to conduct information about injuries such as pin-pricks or other injuries from sharp objects to extremities such as fingers. The brain would perceive this as a sudden stabbing pain in that exact region. C-fibers then take a few more seconds to signal more generalized, persistent pain. This combination allows the cerebral cortex to assess the entire situation associated with the pain, and what action the body should take in response to it.
The body’s response to pain includes the release of several neurotransmitters and neuromodulators, such as gamma-aminobutyric acid (GABA), endorphins, serotonin, and norepinephrine for natural forms of pain relief. Pain fibers may continue to fire (or signal) for some time after the initial injury or other trauma, to remind the brain and body that the damage is still there and is in need of healing, pain-modulating and other protective mechanisms (including keeping the injury clean or otherwise free of further damage). An understanding of these processes contributes to the clinical investigation and development of improved pain management strategies.
Other Factors That Affect Chronic PainIn addition to this neurobiological basis of pain, other variables or factors may also influence pain severity or perception. These include:
- Individual variations, such as pain tolerance
- Psychological factors
- Cultural factors
Pain tolerance may be defined as the intensity or duration of pain that an individual is willing to endure for a given period of time or extent of another variable. Individual differences in pain tolerance may be considerable. This may be influenced by other factors, such as stress, fatigue, emotional state, psychiatric health, and general health.
The perception and response to pain may change with advancing age. This may also be affected by other factors, such as the stage of brain development. For example, children may be less likely to respond to or cope with pain effectively. Cultural factors may also play a role in pain perception, or in the response to pain. In another example, the overt perception of pain may be considered a sign of increased frailty or inability to cope in some cultures. People from other cultural backgrounds may hold extremely negative beliefs concerning pain. These may influence the response to and recovery from pain. On the other hand, some cultures may view pain as adversity that must be beaten in order to function adequately.
Pain, as mentioned above, can also be affected by psychological factors. These include anxiety, fear, negative beliefs, and depressive symptoms. Some researchers assert that increased anxiety and fear increase pain perception. Coping (or the ability to adapt to or recover from the effects of adverse situations) may also be a component of pain perception. Reduced coping abilities may increase the perception of pain, or affect the rate of recovery from a painful condition. Other factors are pain catastrophization, which is a state of exaggerated fear, anxiety, reduced coping, and negative beliefs in response to or in anticipation of pain. This phenomenon may also affect recovery from trauma or illness. On the other hand, some people believe they can cope with pain adequately without help or treatment. This may lead to developments in serious conditions over time.
Conditions Related To Chronic Pain ManagementPain can be associated with many conditions related to either mechanical trauma or physiological disorders. These include:
- Bone fractures
- Ligament damage (e.g. strains or sprains)
- Tendon damage (e.g. tears or other damage)
- Damage or disorders of fascia (tissue connecting muscle to other forms of tissue)
- Muscle damage
- Joint damage or degeneration (i.e. the progressive erosion of cartilage or other joint components over time)
- Back and lower back pain (this may be associated with damage to the muscles, ligaments, or nerves that surround the spinal column)
- Visceral pain (or pain arising from damage in the major organs located in the abdominal cavity)
- Pain in the genitals
The risks and progression of any of these conditions may be influenced by many variables or factors. These include:
- Nerve damage
- Bone loss
- Muscle tissue loss
- Mechanical wear and tear
Pain Assessment And Its Role In Comprehensive Pain ManagementPain is assessed using a variety of rating systems that measure patient self-reports of pain and assign this to a corresponding place on a scale or other measure of intensity or functional impairment.
Some specific conditions may require variations and adaptations of these scales and systems. These may help in quantifying pain and assigning an appropriate treatment that should elicit the necessary level of relief. Pain assessment should also help analyze the effect of non-treatment or inadequate treatment on long-term conditions or severe cases of some disorders.
Chronic pain scales
Pain assessment methods (or tools) require patient interviews that are structured to include specific questions concerning the severity, duration, and location of the pain. A doctor or specialist may ask a patient to rate their pain according to a scale or range that is as universal as possible. These are the basis for tools such as the numerical rating scale (NRS), visual analog scale (VAS), and the Wong-Baker FACES scale.
The VAS has been developed as a straight-line scale with the term “no pain” placed at one end and the term “worst pain imaginable” at the other. A doctor or specialist may instruct a patient to specify a point along the line in either direction where they believe their pain belongs. VAS scores are recorded as numerical values based on the distance of this point from either end of the scale. This helps medical professionals determine pain severity.
The NRS is a numerical scale, from zero to ten. Here, zero corresponds to no pain and ten represents the term “worst pain imaginable.” A patient is required to nominate the number that best represents the severity of pain in their case.
The Wong-Baker FACES scale is a system of pictorial representations of facial expression that also corresponds to a numerical scale. This tool is most useful in pediatric pain and for older people with disorders concerning the ability to order and interpret numerical values. These representations of facial expressions may range from a happy, unconcerned face that could correspond to a zero on the NRS, to a face in extreme pain (that may be crying or otherwise expressing severe adversity) corresponding to a ten.
Diagnosing chronic pain
These tools help to analyze severity of pain. However, they do not answer other pertinent questions such as the duration of pain. These may be covered in other sections of patient interviews, which include questions concerning:
- The exact location of pain (or where the pain is perceived as coming from)
- The frequency of pain (i.e. whether it occurs in regular episodes or is constantly experienced—this is particularly relevant to some chronic conditions)
- A specific event (e.g. an injury) that may be related to the start of pain
- When the pain started, in the absence of the above
- Specific triggers, or factors that seem to be associated with the onset of a pain episode, if any
- The nature and type of pain experienced (e.g. burning, stabbing, etc.)
- Any other factors that affect pain (or may not have the expected effect), such as over-the-counter medications
Other techniques apart from patient interview, such as physical examinations, may also be necessary to assess or diagnose a cause of pain. Physical exams help a doctor identify a condition that is likely to be causing pain, or the severity of an acute injury such as a bone fracture or muscle damage. The physical examination includes assessment of body regions apart from the region(s) from which the pain appears to originate. The physical examination may also involve one or more of these techniques, based on the patient’s history:
- Visual inspection of the body, or specific parts of it, which may allow detection of certain characteristics of specific conditions, if suspected. These may include posture defects, abnormal swelling (e.g. in joints), or limps.
- Palpitation, in which the physician searches for or confirms the presence of the anomalies as above by hand.
- Listening to the patient’s lungs, heart, and blood vessel function using a stethoscope or similar instrument. These vital signs may change in response to pain or illness.
- Tapping the skin over certain organs or structures with a hand or finger. This creates an audible vibration that may help approximate the size and density of these structures.
Diagnosis or assessment may be further enhanced through the use of noninvasive imaging equipment. These may help visualize changes in organs or tissues that indicate an underlying condition or injury. Imaging techniques used in patient assessment include:
- X-ray imaging
- Computerized tomography
- Magnetic resonance imaging
These techniques are accurate enough to scan tissues at the cellular or nearly-cellular level. Therefore, specialists and physicians may locate, identify, and analyze structures such as nerve fibers, and assess the probability of damage in these. Imaging is also used in the guiding of equipment such as needles in the course of surgery. This is also employed to enhance the accuracy of some pain management techniques.
Other diagnostic techniques involve range of motion studies, which assess the levels of motor or functional impairment in some painful conditions. The analysis of some biochemical markers (i.e. increases in the concentrations of some proteins or other biological molecules) of disease may also be useful in diagnostic processes and pain management.
Comprehensive Pain Management StrategiesPain management plans require a comprehensive design to achieve adequate pain relief for the individual patient. Management strategies may be adapted based on the pain type, condition, or injury in question.
To this end, a single comprehensive pain management plan may combine non-pharmacological, drug-based, and interventional pain treatments. The general aim of pain management is to work with patients in order to regain the greatest possible level of mobility and function and improve life quality.
Pharmacologic ApproachesThis may also be known as drug therapy, analgesic treatment, or pharmacotherapy.
This option uses a range of conventional drugs that are approved by many regulatory and medical authorities worldwide. In addition to these are new drug products currently in testing or development to assess their contribution to future pain management. These are typically only available in clinical trial or post-market surveillance stages of approval. Many conventional pain medications drugs are associated with effective pain relief, depending on the specific condition or injury concerned. They are also recommended based on a diagnosis of a specific cause of pain, and the severity of pain in each individual case.
Pharmacotherapy generally begins with a conventional first-line pain medications, including those available over-the-counter in many stores. The most common of these are non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen. NSAIDs reduce pain based on the observation that many conditions associated with pain involve the production of excess inflammation. This damages sensory nerves in the vicinity of the inflammation, which results in pain signaling. NSAIDs inhibit an enzyme involved in the production of inflammatory chemicals in the body. Acetaminophen also reduces pain via a different pathway. These drugs may be prescribed continually or be taken at need in response to the onset of pain. However, long-term NSAID intake is associated with adverse effects such as gastric ulceration, kidney damage, and elevated liver enzymes.
These are medications associated with the treatment of epilepsy, but have been found to also possess analgesic properties. Examples of anticonvulsants include:
Antidepressants increase the availability of neurotransmitters, most often serotonin or norepinephrine. In some cases, they have been phased out as medications for depressive disorders by newer medications, and are now exclusively applied to pain management.
Some examples of these include:
Muscle relaxants are also sometimes known as sedatives, and are also used to treat muscular pain. These include:
Muscle relaxants are commonly recommended for musculoskeletal pain, such as some forms of back pain. The side effects associated with these drugs include nausea, dizziness, and liver damage in severe cases.
Some forms of pain, including superficial somatic pain, may be treated by applying cream or gel formations containing active drug ingredients to the skin. This is then absorbed through the skin to the tissues affected by injury or disease.
Drugs included in topical formations include:
- Diclofenac (an NSAID)
Interventional Pain Management Or Alternative StrategiesSome patients may not show an appreciable response to drug therapy, or choose not to engage in this option due to concerns about side effects and other issues such as dependence or cost. These patients can consider other interventional or non-medical options when deciding on their comprehensive pain management plan. These treatments can be non-invasive or minimally invasive, and may result in pain relief and improvements in everyday life.
Many patients experiencing chronic pain attempt many techniques or treatments in order to regain normal function or life quality. Quality of life is defined as normal daily life without disproportional adversity such as pain. This is a common outcome or measure used in many studies of pain management applications and new therapies.
Alternative, or complementary, pain management strategies are often used in conjunction with medical therapies, or as alternatives to this based on patient preference. Interventional pain management procedures are therapies involving the use of drugs or other medical applications, but in ways that require their practice by a licensed and competent healthcare professional. Many studies and research articles indicate that a combination of one or more of the techniques of either category, often with added drug therapy, results in the most effective comprehensive pain management plans.
Both forms of alternative therapy may be available at a pain management clinic or similar facility. Combinations of these are devised following extensive assessment by and consultation with a pain management doctor, and possibly other members of a disciplinary team. The result of these is a comprehensive pain management plan (or “care plan”). These programs may include one or more of the following therapies.
This interventional pain management technique involves the direct delivery of drugs to either the source of pain or to spinal nerve tissue associated with a case of pain. Examples of these include steroid injections. Steroids are drugs that may significantly reduce inflammation and thus pain emanating from a particular body part, such as joints affected by painful conditions like rheumatoid arthritis. Steroids may be injected directly into these regions, in techniques referred to as an intra-articular or joint injection. These drugs may also be injected into the periphery of the spine for more direct pain inhibition. This technique is known as an epidural steroid injection.
Other drugs that may be injected (with or without steroids) include fast-acting numbing agents known as local anesthetics. These target nerves in or near the spine (which are known as nerve blocks) or into some major cranial nerves (e.g. the occipital nerve) for effective pain relief. These drugs are also applied topically, to prevent discomfort as the needle is inserted in the course of an injection procedure. Imaging techniques such as fluoroscopy are used to guide the needle to the appropriate location for injection.
Implantable pain management devices
Some devices may be placed inside the body during often-minimally invasive surgeries to provide comprehensive pain management in cases of severe chronic pain that does not respond to other forms of therapy. These include intrathecal pumps, which are catheter-like devices implanted into areas similar to those that are the target of spinal nerve blocks. These devices are connected to a small reservoir of drugs such as fentanyl, with a pump mechanism that delivers a fixed dose of these through the catheter. These can be activated by the patient when they sense oncoming pain. The intrathecal pump method of pain relief has demonstrated long-term efficacy as an interventional pain management option.
Radiofrequency ablation is an interventional pain management technique that uses a specialized device to disrupt nerve conduction and pain signal transmission. It’s best used for people with back or neck pain, but can be used for multiple other pain conditions.
The following video gives a demonstration of a radiofrequency ablation procedure. You can find even more demonstrations of interventional pain management techniques on our YouTube page.
This is a form of manipulation in which practitioners mainly work on conditions affecting joints or muscles. Chiropractic manipulation is linked to improvements in:
The joints between individual bones in the spine (vertebrae) may be subject to abnormalities in terms of their normal alignments or interfaces. This can result in damage or strain to the surrounding muscles or nerves, which results in pain. Chiropractors employ manipulation to correct these deformities, returning spinal bones to their correct location or alignment over time. Some studies have demonstrated positive effects on pain as a result of chiropractic manipulation.
Acupuncture is a complementary pain management option that is derived from traditional Chinese medicine. This involves the insertion of thin, sterile needles through the skin. These needles may target the area associated with pain and alternate locations. This is thought to promote the release of endorphins, thus improving the body’s response to pain. Acupuncture may also enhance blood flow, which is also linked to the improved response to pain-relief treatments.
Active release technique (ART)
This is a form of manual therapy (similar to chiropractic manipulation) that uses specific manipulations with the fingers and hands, while the patient makes corresponding or opposing muscle movements. This is thought to relieve strain and damage to muscle tissue, and improve movement and function in cases of musculoskeletal pain. ART is also linked to improvements in pain associated with scar tissue and other forms of tissue damage. This treatment may also improve muscle structure and function in some patients. It is also linked to pain and reduced functionality in some rare cases.
Biofeedback is a non-interventional pain management procedure in which the patient learns improved coping skills. This is done through their education on several different vital signs (e.g. heart function, skin temperature) and how they are measured (i.e. by electrocardiograms, galvanic response, etc.), and how these may change in response to pain. Patients are then taught relaxation and coping exercises, and how to apply them in response to these changes. The patient may monitor these vital signs using small mobile devices or monitors. Some studies have demonstrated the beneficial effects of biofeedback training on many cases of pain.
Botulinum, or botulinum-A toxin, is a compound that disrupts the connections between nerve cells and muscle. This has been shown to reduce pain in cases of musculoskeletal damage or disorders. This interventional pain management option has also demonstrated positive results in trials including patients with migraine and neck pain.
Cold laser therapy
Cold laser therapy is a form of laser (or highly focused light) that when directed at human tissues causes cell behavior alterations. This has been found to enhance healing and thus facilitates pain relief. Cold laser therapy is FDA-approved for the treatment of chronic and acute forms of pain.
Cognitive-behavioral therapy (CBT) is a type of psychotherapy that focuses on the promotion of positive and constructive thinking at the expense of negative thinking. This may alleviate the effect of psychological factors, such as negative beliefs and catastrophization. CBT may enhance coping and recovery from pain in this way. CBT is associated with beneficial effects in conditions such as rheumatoid arthritis, back pain, fibromyalgia, and cancer. Using CBT or another type of approved talk therapy is an important consideration when creating a comprehensive pain management plan.
Exercise counseling and nutrition
Many comprehensive pain management plans involve patient education on the effects of diet and lifestyle on painful conditions and overall health. This includes information on the role of exercise and improved nutrition in recovery from pain. For example, deficiencies in vitamin D or calcium may aggravate conditions such as osteoporosis. In addition, there is evidence that behaviors such as alcohol abuse and smoking have a negative impact on tissue healing, pain perception, and recovery from pain.
ConclusionNearly all human beings are at a risk of pain through mechanical or physiological damage. Acute or chronic forms of pain may have a considerable effect on normal function or life quality for many people. There are many theories and scientific advances in the study of pain and pain relief, but also much potential for further learning and development. Pain, particularly when related to untreated chronic conditions, can have significant effects on an individual. These include the inability to complete normal everyday tasks, function in an occupational capacity, and maintain a normal psychological state.
A comprehensive pain management approach depends on the accurate diagnosis of underlying conditions and trauma. This diagnosis may also dictate the types of pharmaceutical, alternative, or interventional pain management strategies used to improve life quality for the individual patient. A pain specialist or physician must often work with other practitioners, including mental health professionals, practitioners of complementary therapies, and nurses providing healthcare and patient education, to deliver an optimal pain management plan.
These plans may include a combination of drug therapy, interventional pain management, and complementary therapy. Comprehensive pain management plans may also need to adapt and change in the event that a patient does not respond as expected to one or more of these treatments. The overall goals of comprehensive pain management include the effective, robust, and reproducible alleviation of pain and the maximal retention of life quality and function for all patients.
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