Chronic pain, once thought of as something more psychological than physiological, is now better understood because clinicians and pain specialists comprehend more fully how pain and its sensations work at the level of the nervous system. The feeling of pain stimulates a myriad of emotions, but has its basis in the peripheral nervous system and spinal cord and how both interact with the brain to create the actual sensation of pain. The action of neurotransmitters, the chemical messengers that pass nerve signals, suggests possible new modalities to relieve pain, particularly regarding mechanisms to redirect the chemical messengers to modulate the way the brain interacts with the signals.
Opioids, antidepressants, and other drugs that work with specific brain chemicals, such as dopamine, that affect emotions and influence the perception of pain have been the mainstay of pain treatment. However, pain specialists can now prescribe treatments that attack moderate-to-severe chronic pain from different angles using targeted electromedical modalities, such as spinal cord stimulators, electroanalgesic delivery systems, and pulsed radiofrequency therapies, which will be the focus of this article. These technologies have the added advantage of being nonaddictive and drug-free, eliminating drug interactions and minimizing the potential for medical errors, side effects and overdose. New technologies being employed for pain relief also support patients who are being weaned off narcotics.
The use of electrical signals for various medical treatments has been documented in historical records as early as 2750 BC, with reference to the electrical properties and treatment potential of the Nile catfish Malopterurus electricus.1 In more recent historical periods, even Benjamin Franklin documented pain relief by using electrical currents for a number of ailments, including frozen shoulder.1
While prescription medications are still the mainstay of pain relief and can be prescribed using e-prescribing technology in some states, innovative technologies are now being considered to synergize and sometimes replace these therapies.2 Today, the clinical use of electro-medical modalities in both diagnosis and treatment is well documented, with references demonstrating the positive effects on patients for a myriad of medical conditions such as chronic sciatica, pain related to peripheral vascular disease, failed back surgery syndrome, or complex regional pain syndrome.3
While these modalities differ in their delivery mechanisms, they essentially do the same thing by using electrical signals sent to the brain to interrupt and/or block sensations of pain. Several devices, such as the trans cutaneous electrical nerve stimulation (TENS) unit, have the support of the FDA, Medicare, and even the insurance industry, creating a path for coverage and thus accessibility for patient use.4
Spinal Cord Stimulators
Spinal cord stimulators are innovative
devices implanted in the back; they are very compact—the typical size is
as small as a silver dollar. The device is inserted in fatty tissue in
the lower back and the electrodes are inserted into the spinal canal
(see FIGURE 1
below). When in operation, the system sends signals to the spinal cord that redirect the brain to avoid registering pain.5
The patient can turn the device on and off and can control the
frequency of the actual signals with a remote controller similar to a
garage opener. The technology “tricks” the brain into feeling good
sensations rather than bad. This device is usually reserved for those in
constant and persistent pain, such as might occur with such diagnoses
as severe back injuries, shingles, or other chronic pain syndromes, who
have otherwise exhausted their options. It also relies on surgical
implantation, so a patient does run added risk of complications from the
surgery such as infection, bleeding, and paralysis.5
Electroanalgesic Delivery System
Electroanalgesic delivery system treatments involve the use of computer-modulated electronic signals that extinguish or block the function of somatic or sympathetic pain nerve fibers. An electroanalgesic medical device (EAD) is used to produce and deliver high-frequency signal energy using a computer algorithm that continually generates a varying sequential and random pattern interrupting nerve axon transport of pain signals; the signal is delivered via specialty electrodes.6 The signal energy incorporated by the EAD has a much higher electrical frequency than the standard TENS technology, which relies on amplitude modulation (AM) of a lower frequency electrical current being delivered to the body. The TENS technology is similar to the familiar concept of AM radio waves. EAD technology, on the other hand, delivers electrical signal current to the body as amplitude-modulated (AM) current in combination with frequency-modulated (FM) current. This would be like mixing an AM and FM radio station, and it results in a much more complex pattern of current. This complex pattern is so variable that the nervous system cannot accommodate it, and the pain nerves are essentially shut down. EADs appear to be very potent in their ability to mitigate, reduce, or quench acute and/or chronic intractable pain conditions, and are more effective than the older TENS technology. Effectiveness of electroanalgesia nerve blocks at sympathetic ganglia may be as high as 75%, with very little risk.7
Pulsed Radiofrequency
Pulsed radiofrequency (PRF) is a novel therapeutic modality with many potential applications in pain management. PRF is a more sophisticated variation of conventional continuous radiofrequency (CRF), which has been in use since the mid-1970s. CRF causes localized heating of tissue and results in very controlled tissue destruction. PRF offers the advantage of pain control but without associated tissue destruction or other undesirable and painful sequelae associated with CRF.8
Although very promising, PRF is still in its developmental stage. PRF relies more on modulating the electrical or magnetic field without generating excessively destructive thermal/heating effects. It appears that PRF is at least a hundredfold less destructive than CRF. This theoretical benefit of PRF is especially promising in cases of intrinsic neuron-generated (neuropathic) pain in which CRF is relatively contraindicated.8
The mechanism by which PRF controls pain is unclear, but it may involve a temperature-independent pathway mediated by rapidly changing electrical and/or magnetic fields that are thought to modulate the transmission of pain signals.8
Although much anecdotal evidence exists in favor of PRF, there are few quality studies substantiating its utility or exploring the efficacy of PRF in treating pain. Additionally, most reports are retrospective in nature and involve only small patient cohorts. The bulk of PRF research has been conducted in patients with axial low back pain; however, in recent years, PRF has been studied in a wider range of conditions.8
The Role of EHRs
Finally, the use of an electronic health record (EHR) can be useful for capturing data and seamlessly delivering it to the clinician who is taking care of a patient living with chronic pain. Any pain management practice is fraught with complexities, including care plans involving not only innovative technologies but also pharmacologicl treatments, interventional procedures, or alternative therapy. Ensuring that an EHR can support these elements is essential to achieving efficient and reliable quality of care.
It is, however, very important to chose the correct EHR for a pain management program. Some features to look for in an EHR for a pain management practice include the following:
Customized care plans with easy import of data from various sources to demonstrate patient pain improvement over time. These are vital to support pain management programs. Many care plans support these electronic therapeutic modalities and are already pre-formatted and fully customizable for various treatment objectives and goals regarding a specific diagnosis.
Flow sheet capabilities. Flow sheets allow clinicians to review current and past treatments and any laboratory results. Having the ability to review therapies that worked and those that were not successful helps determine the most appropriate care pathway for a patient experiencing pain.
Ability to print controlled substance prescriptions onto state-regulated printing paper. This is helpful for pain specialists, who prescribe controlled substances and would e-prescribe them as well if possible.2
Communication with other care providers, such as the oncologist or the primary care physician, is also critical for coordination of care and is an element of Meaningful Use stage 2. The Meaningful Use program is a Medicare and Medicaid program that provides incentive dollars to providers for the adoption and meaningful use of certified EHRs. Electronic communication of care plans between providers can be accomplished via a health information exchange (HIE), a network allowing EHRs to seamlessly exchange information. When an HIE is not available, the care plan can be transmitted via the Nationwide Health Information Network Direct protocol, which is essentially a form of encrypted e-mail between providers. From a governmental and reimbursement perspective, supporting Meaningful Use stage 2 is vital and requires documentation in each encounter.9
Conclusion
Pain is a universal experience, whether it results from injury or the effects of a disease state. The experience of chronic pain, however, is an enduring challenge, causing in most instances severe debilitation if not effectively treated. Having novel approaches besides the basic pharmacologic modalities can add a dimension of therapeutic support to the clinician who seeks to stabilize a patient’s chronic pain.
REFERENCES
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4. Center for Medicare and Medicaid Services.
Medicare
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www.cms.gov/Regulations-and-Guidance/Guidance/Manuals/downloads/bp102c15.pdf.
Accessed January 14, 2014.
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8. Byrd D, Mackey S. Pulsed radiofrequency for chronic pain. Curr Pain Headache Rep. 2008;12:37-41.
9. CMS.gov. Centers for Medicare and Medicaid Services.
Regulations and guidance. EHR incentive program. Stage 2. Updated
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www.cms.gov/Regulations-and-Guidance/Legislation/EHRIncentivePrograms/Stage_2.html.
Accessed February 14, 2014.
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