What Is Pain Management?
Pain management explained by San Antonio, Austin, Houston, Dallas Texas top pain doctors
Pain management is the definition of all the treatments and strategies an individual may employ in an attempt to reduce pain and reverse the deleterious effects of pain on their functional status or life quality. There are many options to alleviate both chronic and acute pain. Pain management, in the form of plans or programs, may include non-medical interventions such as physical therapy or patient education. This may require collaboration between health professionals such as pain specialists, nursing practitioners, and practitioners of other alternative therapies. This is termed the interdisciplinary pain management team. Plans may be the result of consultation between these people and the patient on the best therapies and treatment methods that can 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.
Pain is the body’s response to noxious or harmful stimuli. Its function is to induce avoidance of external pain sources in an individual, or to alert an individual to damage or disorders of internal structures, such as bones or organs. It also results in other effects, including psychological and physiological responses. Some types of pain may result from dysfunction or damage to the nervous tissue that conveys information about noxious stimuli to the brain. This can lead to pain that persists long after the source of this stimulus has gone or is resolved; for example, after an injury has healed. This is associated with a variety of chronic pain conditions.
Other forms of chronic pain may start as a low level of pain that is only vaguely noticeable, but intensify over time to the extent that it significantly affects daily life. On the other hand, pain may have a more abrupt onset and resolve itself within a short time. This is known as acute pain. The severity of acute pain can range from mild to severe, but also warrants treatment. Some forms of acute pain may affect the risk of chronic pain conditions in the future. Acute pain typically lasts a number of days to weeks, whereas chronic pain may persist for a number of months or longer. Chronic pain is often related to decreases in mobility or normal function. Pain management often plays a vital role in the prevention of this.
Current national health guidelines suggest that pain persisting for three months or more may be defined as chronic pain. However, this can be subject to change, based on the specific condition diagnosed as a cause of pain. Research indicates that the effect on measures of functional status such as an individual’s life quality associated with chronic pain is significantly greater than that of any other similar factor. Many researchers and healthcare professionals regard chronic pain as a serious socioeconomic and healthcare issue. Prominent forms of chronic pain include back pain, hip pain, and headache-type pain. These affect millions of people in the U.S. every year.
Pain is a nearly universal experience. However, it is also very subjective, i.e. each individual may describe and perceive pain differently. This makes the standard classification and measurement of pain highly difficult, which is a challenge for many scientists. In addition, people may also exhibit considerable individual differences in the capacity to function and cope with pain. This poses challenges in the analysis of and proposals for treatments in pain research. Pain specialists and treatment practitioners also face these challenges, particularly when diagnosing a case of pain.
Pain that is untreated in the long term is associated with increased risks of significant physiological and psychological adversity. Pain may have an impact on many daily activities and functions such as the ability to sleep or eat. It can lead to functional and motor impairments in advanced or severe cases. Some studies indicate that chronic pain also has a deleterious effect on concentration, cognition, and memory. Psychological effects of pain include depressive symptoms, fear, intense feelings of helplessness, anxiety, impairment coping, and considerations regarding suicide in severe cases. Doctors and pain specialists should consider the possibility of these symptoms when assessing a patient with chronic pain. Members of the team of specialty physicians and other professionals may assess the need for psychological help. This team may include mental health professionals, physical therapists, pain specialists, other or alternative practitioners, and various types of nursing practitioners. This team can deliver a complete treatment plan or diagnosis for the patient in question. Pain management plans may involve one or more medical intervention therapies.
Biological Mechanisms Of Pain
Pain originates from malfunctions or injury in the pain receptors located on the cells of the body’s sensory nerves, or damage to these nerves. Alternatively, other psychiatric or physiological disorders may be associated with pain. Pain management is based on the current understanding of these mechanisms. The processing and perception of pain signals mainly involves peripheral nerves, or nerves that split off from the central nervous system (the spinal cord and brain) to radiate into nearly all body parts.
Pain as a sensation originates when tissue damage results in the electrical stimulation of nerve cells carrying pain receptors (nociceptors), which relay this as more electrical impulses to the brain. This damage may be as a result of trauma or injuries to the body, often related to an external influence. This is known as visceral or somatic pain. The somatic pain type is categorized as either deep somatic or cutaneous pain. Cutaneous somatic pain is associated with the skin or tissues located under the skin, and deep somatic pain is associated with tissues such as the blood vessels, bones, fascia, and nerves. Visceral pain is associated with the stimulation of the pain receptors located in the abdomen (or thorax). Exceptions to these pain types may be defined as psychogenic or idiopathic pain.
Pain signals emanating from nerve cells is relayed or conducted to a brain region termed the cerebral cortex. A part of the cerebral cortex, known as the somatosensory cortex, is capable of analyzing these signals in terms of intensity and location. Pain signaling is initiated in the spinal cord, which interfaces with peripheral nerve endings (or roots). This happens in an area referred to as the dorsal horn of the cord (which is a band of nerve cells that curve up within each half of the cord to resemble a horn). These cells possess nociceptors, which when activated cause the activation of other spinal cord cells, which then activate other cells on the way to the brain, and so on until the signal is eventually picked up by the cerebral cortex.
The nerve cells that transmit noxious stimuli from peripheral areas of the body to the spinal cord are bundled into nerve fibers. These are divided into A-type fibers and C-type fibers. A-fibers or “fast” fibers relay signals at remarkable speeds that often correspond to the perception of very sharp and abrupt pain. C-fibers or “slow” fibers relay more generalized, persistent pain that is often described as a burning sensation. A-fiber signaling may be used to relay the sensations associated with injuries such as specific lacerations or pin-pricks. The brain would process this as an acute lanciating pain in the relevant region. C-fibers then follow this up with more persistent widespread pain. This combination allows the full analysis of the pain by the cerebral cortex, and may also affect pain duration and severity.
The brain responds to noxious stimulation through the release of several types of molecules called neurotransmitters and neuromodulators, such as norepinephrine, gamma-aminobutyric acid (GABA), endorphins, and serotonin. These control natural forms of pain relief and other physiological responses to pain. Pain fibers may be continually active for a period of time after damage such as injury. This maintains the response to pain for as long as necessary, and encourages behavioral reactions such as keeping a wound clean or free from undue stress. Medical or scientific variations or modulations of these functions are the basis of pain management research.
Additional Factors Of The Pain Response
Other factors or variables also play a role in pain perception or severity. These include:
- Age: The response to and perception of pain can vary with age. This may also be affected by other factors, such as brain development, prior experiences with pain, the progression of age-related conditions, or properties such as healing and psychological state. For example, an older adult with a chronic condition may report less pain than expected because they have become “used to” the pain.
- Cultural factors: Cultural factors may play a role in the response to pain or pain perception. Some cultures discourage the expression of pain or seeking treatment for it. Others involve very negative convictions about pain and some conditions relating to pain. Cultural factors may also affect recovery from pain. Alternatively, some cultures view pain as challenging but not impossible to overcome.
- Pain tolerance: This is described as the duration and intensity of pain that an individual is prepared to withstand. This may differ greatly from patient to patient. Pain tolerance can be influenced by its own array of related factors, including fatigue, emotional state, stress, psychiatric health, and overall health.
- Psychological factors: Psychological factors that affect pain include fear, anxiety, depressive symptoms, and negative beliefs. There is some evidence that increased fear or anxiety are inversely correlated to pain perception. Coping (or the ability to confront, recover from, or adapt to adverse situations) may also affect the pain response. Impaired coping skills or strategies can impact the pain perception of, or ability to recover from, pain for a patient. Pain catastrophization is a condition in which a patient experiences disproportional fears, impaired coping, anxiety, and negative beliefs in anticipation of or in response to pain. Studies have demonstrated the effect of pain catastrophization on recovery from pain or other symptoms. Alternatively, other forms of belief lead some people to cope with pain without seeking help or treatment. This may lead to worse deterioration over time.
Conditions Related To Pain Management
More specific types of pain may be related to trauma or disorders in many parts of the body, or to nervous tissue damage or disorder as above. Your pain doctor will offer consultations, diagnoses, and treatment plan options for many of these. Pain felt in one part of the body may be explained by damage or dysfunction in a variety of tissue types depending on its location.
Painful conditions and trauma include:
- Bone fractures: These are total or partial cracks that occur in many types of bone in the body. Fractures may be the result of direct mechanical damage, e.g. blunt-force trauma, motor vehicle collisions, etc. The risk of bone fracture tends to increase with old age, as conditions such as osteoporosis affect bone quality, which increases the risk of breakages in this tissue.
- Ligament damage (e.g. strains, sprains): Ligaments are bands of connective tissue that connect one bone to another. Mechanical damage can cause pain in these structures. The risk of ligament damage is influenced by athletic activity, injuries such as falls, abrupt twists of one bone relative to another, and repetitive strain.
- Tendon damage (e.g. tears or other damage): Tendons are structures similar to ligaments that connect muscles to bone. The risk factors of tendon damage are similar to those affecting ligament damage, and may also include undue load or strain on muscles and inadequate warming-up before engaging in athletic activity.
- Damage or disorders of fascia (tissue connecting muscle to other forms of tissue): This connective material can also become damaged in response to repetitive strain, high-volume exercise, and improper exercise techniques. Injuries to fascia can easily be mistaken for other forms of tissue damage.
- Muscle damage: Damage to muscles, particularly those connected to the skeleton, is another common form of pain. The risk factors for muscle damage are similar to those of the tissues, and may also include joint problems, poor posture, and spinal abnormalities.
- Joint damage or degeneration (i.e. the loss of cartilage or other joint components over time): This is another prevalent form of pain, in which the cartilage that protects the surfaces of two bones that form a joint wears away. This may progress to a point at which the surfaces come into direct contact, which is associated with chronic pain and reduced motility in the joint. Cartilage loss can be associated with increasing age, genetic factors, trauma, autoimmune attack (which is seen in conditions such as rheumatoid arthritis), and inflammation. This is commonly diagnosed in the shoulders, hips, fingers, and in the joints between spinal bones (intervertebral joints). Joint pain is associated with chronic pain and functional decline.
- Back pain: This is another prevalent form of pain, in which pain is perceived as emanating from the back. This can be associated with bone, muscle, ligament, or joint damage. Other conditions that result in back pain include spondylosisthesis (a form of spinal deformity associated with inflammation), spinal nerve damage, damage to the discs of cartilage located between spinal bones (which is known as discogenic pain), and vertebral fracture or collapse. This type of pain may require corrective surgery in the absence of early medical treatment. These surgeries are associated with the risk of new-onset chronic pain due to inadvertent nerve damage.
- Neck pain: This is a similar type of pain, associated with many of the factors as above. Neck pain may also result from whiplash, in which the ligaments, muscles, and bones are damaged due to high-speed impacts. Whiplash is associated with motor traffic accidents and may lead to chronic pain.
- Headaches: There are many types of headache, including a number of migraine types, tension-type headaches, cluster headaches, and neck pain-related headaches. The exact cause of many headache types have not yet been defined, but are most likely to be associated with damage to major nerves leading out of the skull, in combination with some other variables, including genetics. Headache-type pain may be acute or chronic, and may be severe and treatment-resistant.
- Pain in the genitals: This is another common form of pain. It may be related to mechanical trauma (including sexual abuse), some types of cancer, or damage to sensory nerves serving the regions. Pain in these areas can be also be acute or chronic.
The risks and progression of any of the conditions and adverse events as above may be influenced by many variables or factors. These include:
- Inflammation: This is the release of chemicals into a body part that can be associated with increases in temperature and tissue damage in this region. Inflammation is a function of the immune system, which mediates its release into damaged tissue to kill harmful foreign particles such as bacteria and encourage the healing process. Inflammation is also associated with pain, as the exposure of sensory nerves to these chemicals results in pain signaling. Some conditions are associated with excessive or chronic inflammation, and thus chronic pain. These include rheumatoid arthritis, lupus, spondylolisthesis, and many headache types. Inflammation is also released by damaged tissues, and is therefore present in cases of muscle, tendon, or ligament damage.
- Nerve damage: Damage (whether mechanical or physiological) to nervous tissue in or near the spine can result in the perception of chronic pain in the back or in other areas, depending on the peripheral nerves associated with the spinal nerve(s) in question. Damaged nerves can send consistent, uncontrolled pain signals to the brain. This is often referred to as neuropathic or radioculopathic pain. These conditions may also be related to chronic inflammation around these nerves.
- Genetics: Variations or mutations in many genes affect the risk of many chronic conditions, including headaches.
- Bone loss: Osteoporosis is the progressive loss (and failure to repair) bone tissue over time. This is associated with increasing age, menopause, and deficiencies in vitamin D or calcium. These nutrients contribute to bone formation or healing. Osteoporosis is associated with the increased risk of fracture, and may also contribute to the pain of joint damage and to chronic pain in general.
- Muscle tissue loss: This is also known as sarcopenia and is also associated with advanced age. Reductions in tissue mass can result in further deteriorations in joint conditions, as these structures lose the support of the muscles around them.
- Age: This is strongly associated with many painful conditions. Increased pain in older adults may also be associated with the increased risk of disability.
- Mechanical wear and tear: This contributes to progressive deteriorations in cartilage, ligaments, bones, and tendons. Wear and tear over time may affect the progression of chronic pain.
Pain Assessment And Its Role In Pain Management
Pain management plans and their designs are greatly aided by the accurate diagnosis of a condition can cause chronic pain and the assessment of pain severity for each individual patient. A pain specialist may use rating tools such as numerical or visual scales of pain severity to diagnose and analyze pain. He or she may also conduct detailed interviews with the patient to ascertain the nature and duration of the pain.
Physicians and specialists also use other diagnostic tools, such as external imaging techniques. These provide visualizations of injuries such as fractures, strains, or sprains. They can also detect conditions such as neuropathy, joint deterioration, osteoporosis, and spondylolisthesis. Imaging equipment used in diagnosis include computerized tomography, X-ray imaging, magnetic resonance imaging, or fluoroscopy.
Physicians and specialists identify, locate, and assess damage in structures such as spinal nerves, and recommend treatment options based on this. Imaging techniques are also used in the guidance and placement of implements such as catheters during surgery. This reduces the possibility of inadvertent tissue damage. Other diagnostic techniques involve assessing motor impairments, which are associated with some conditions such as arthritis. Laboratory analysis of blood or other samples, for signs of factors such as increased inflammation or damaged cartilage products, are also useful in diagnosis.
Pain Management Strategies
Pain management plans require multiple treatment types to achieve relative freedom from pain. These are recommended in accordance with the condition, pain type, or injury diagnosed. A pain management plan includes pharmacological and interventional treatment techniques. Pain management strategies are offered with the general goal of appreciable pain relief and also improvements in function, mobility, and life quality.
How Are Pain Management Strategies Performed?
This is the treatment of pain through the ingestion (or absorption via other route) of drugs that have demonstrated significant, effective pain relief in clinical trials and studies. Drug therapy can also be delivered by other routes into the body.
- Transdermal skin patch
These include conventional analgesics or painkillers, and also other drugs that were originally marketed for unrelated conditions. Drug therapy types are recommended based on the type of injury or disorder in question. The type of analgesic drug prescribed also depends on pain severity, as some types are more powerful than others.
A patient diagnosed with arthritis or with an acute injury may be advised to try conventional first-line analgesics, available over-the-counter or on prescription. These include acetaminophen or many non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDs reduce pain by inhibiting enzymes involved in the production of inflammatory chemicals in tissues. Therefore, they effectively reduce pain associated with inflammation. Acetaminophen also reduces pain, but does not significantly affect inflammation. Depending on the condition or injury, these drugs may be taken at need in response to the onset of pain or be prescribed at a continual low dose to control pain in disorders such as spondylolisthesis. However, the use of NSAIDs, especially at a high or consistent dose over time, is associated with side effects such as kidney damage, gastric ulceration, and transient acute headache.
If treatment with conventional painkillers fail, i.e. does not result in effective pain relief, the physician or specialist may then recommend other forms of drug therapy. These include milder opioid or opiate drugs, including codeine and hydrocodone. Some others not normally associated with pain treatment, such as tramadol, have shown positive results in studies of alternative pain management. Opioids are a class of drugs that inhibit nociceptors in the spinal cord (and gut) thus relieving pain effectively. Therefore, they are commonly used in pain treatment. However, these drugs are associated with a number of adverse effects and events.
The use of opioids is associated with high tolerance, or the need for increased concentrations of a drug for the same result over time. This may increase doses taken, and thus the risk of adverse effects. These include skin complaints, nausea, sedation, constipation, respiratory distress, and organ damage. Opioid use can also be associated with other effects, such as overdose and immune system defects. Prescription opioids are most often available as oral tablets or transdermal patches.
Other drugs in this class include:
Patients with chronic, severe, and treatment-resistant pain who are not satisfied with these strategies may consider other opioids such as fentanyl or morphine. These drugs can be taken transdermally, orally, or via intrathecal pump. These drugs, however, are related to an increased profile of abuse or addiction. Abuse is defined as the addiction to or over-use of a substance to the extent when an individual significantly loses the ability to work, socialize, or function as normal.
Some other drugs are currently prescribed as pain treatments that have been found to effectively reduce chronic or acute pain in clinical studies. These may be members of drug classes not historically linked with analgesia, but have been re-purposed as alternative pain management strategies in recent times.
These are medications originally intended to treat epilepsy, but they have been found to reduce pain for many patients. Examples of these drugs include:
Antidepressants increase the availability of, or prevent the metabolism of, some neurotransmitters, most often norepinephrine or serotonin. In some cases, these are older products in this class, and have been found to be ineffective in the treatment of psychiatric disorders compared to newer compounds. However, they have proven effective in studies of headache (most often migraine or cluster-type headache) treatment.
Some examples include:
These are also sometimes known as neuromuscular blockers, and are useful in the treatment of muscle damage and some types of back pain.
Examples of muscle relaxants include:
The side effects associated with these drugs include dizziness, skin disorders, nausea, and liver damage in severe cases.
Alternative Routes Of Pain Treatment
Some forms of pain, including superficial cutaneous pain, may be treated by the application of creams or gels containing low concentrations of some analgesic drug to the skin (or muscles under skin) affected by pain. These drugs are absorbed into or through this skin to the damaged or otherwise painful tissues.
Drugs included in these formations include:
- Diclofenac (an NSAID)
- Carbamazepine (another muscle relaxant)
Interventional And Alternative Treatment Options
Some patients may not be satisfied with drug therapy, due to failure of analgesia in these cases, side effects, or other issues such as cost and dependence. In these cases, your pain doctor may recommend interventional therapies. These treatments are generally minimally invasive, or non-invasive, and are also associated with pain relief, as well as improvements in functional status and life quality. The life quality of an individual may be defined as everyday life without excessive disruptions by factors such as pain. This is also a common focus in pain management research and applications. Many patients with chronic conditions respond well to interventional treatment options, as they are often associated with longer periods of pain relief than drug therapy.
Interventional therapies may include one or more of the following options.
These involve the more direct administration of drugs to either spinal nerve tissue or the structure associated with pain via a catheter or needle. Examples of injection therapy include corticosteroid injections. These are drugs that may significantly reduce inflammation and thus pain associated with joint damage or other similar conditions. They are commonly recommended to patients suffering from rheumatoid arthritis.
Corticosteroids can be injected directly into painful joints, in procedures known as a joint or intra-articular injection. These drugs may also be injected into the vicinity of (not directly into) spinal nerves to relieve the pain of neuropathic conditions. This is known as an epidural corticosteroid injection. Other drugs that may be included in these injections (with or without corticosteroids) include local anesthetics such as prilocaine or lidocaine. These may also be injected near spinal nerves. These are known as nerve blocks. They can also be applied to major cranial or peripheral nerves.
Types of nerve-blocking injections include:
- Celiac plexus block
- Occipital nerve block
- Sphenopalatine ganglion block
- Pterygopalatine ganglion block
- Medial branch block
Local anesthetics are also applied to the skin through which a needle is inserted, to prevent discomfort at the start of an injection procedure. Imaging equipment such as fluoroscopy is used to enhance the accuracy of the needle during the procedure.
Some devices can be implanted within the body using minimally-invasive surgical techniques. They provide long-lasting pain relief in some cases of severe chronic pain. Intrathecal pumps are catheter-like devices that are placed in areas close to spinal nerves (as with injection therapy). The catheter is connected to a small reservoir containing drugs such as morphine, and a small pump that introduces a controlled dose through it. The pump can be activated by the patient in response to an episode of pain. Intrathecal pump implants may effectively reduce pain related to conditions such as chronic pain resulting from failed back surgery.
Spinal Cord Stimulation
This is another type of implant also placed in the epidural space of the spine. However, this device delivers electrical stimulation in place of drugs. This stimulus mimics the signals of nerves relaying normal-state signals to the brain. Therefore, spinal cord stimulator implants may correct or over-ride abnormal pain signal levels emanating from damaged or dysfunctional nervous tissue. This is associated with effective, long-term relief from hip, back, or neck pain related to radiculopathy or neuropathy.
Peripheral Nerve Stimulation
This is similar to spinal cord stimulation, but involves the implantation of devices along peripheral nervous tissue instead of spinal nerves. This has demonstrated efficacy in the treatment of conditions such as peripheral neuropathy or headaches (i.e. through implants placed along the occipital nerves). Stimulator devices are placed during minimally- or moderately-invasive surgeries, and have many advantages over other treatments. These include their extended duration of effect, which depends on a battery pack (which can also be placed under the skin and is rarely visible or obtrusive) and may be associated with improvements in mobility and life quality in chronic pain. These devices are recommended for patients who do not respond or are not satisfied with other treatment options. Nerve stimulation, or neuromodulation, may also reduce the intake of pain medications necessary for many patients.
Botox, or botulinum toxin-A, is a neurotoxin that temporarily destroys the connections between muscles and nerve cells. This results in a numbing effect that can reduce musculoskeletal pain. This has also shown potential in the treatment of some headache types. Botox has demonstrated positive results in trials involving patients with migraine headaches and neck pain.
Pain is an almost universal experience, and is typically encountered in conjunction with injury or some medical condition. Pain may be acute or chronic, and it can significantly affect life quality or normal function for those who are subject to it. Pain, especially when left untreated, may adversely affect mobility, functional status, or mental health. Chronic pain is currently regarded as a major factor in healthcare burden, economic burden, and society in general. Pain management is the combination of strategies and techniques to help people reduce and cope with pain.
Pain management options are offered in accordance with the severity of the pain in question and with specific conditions associated with pain, if present. These conditions include neuropathy, rheumatoid arthritis, and osteoporosis. Acute injuries such as bone fractures also require pain management. Your pain specialist may recommend first-line drug therapy at the start of treatment. If these fail, a patient can consider alternative pharmacotherapy or interventional therapies. These include injection therapies, which can produce positive results in cases of arthritis or spinal pain. Other patients with treatment-resistant neuropathy may consider neuromodulation techniques, such as peripheral nerve stimulation.
The ideal outcomes of pain management include long-lasting effective relief from pain and the fullest extent of life quality and functional status improvements possible. If you think your pain management plan may benefit from one of these, contact your doctor today.
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