When it comes to protecting the body, pain perception and sensation is crucial to our physical welfare and care. Unlike some receptors which are limited, such as those stimulate by light or chemicals, pain specific receptors known as nociceptors are found everywhere in the body and are constantly at work to warn of possible injury. Of course, being so important, the transduction mechanism is incredibly complex, relying not only on signals generated by the harmful stimulus on the nociceptor, but also on the supportive and regulator roles of surrounding cells.
In the simplest sense, pain is perceived when a painful stimulus acts upon a nociceptor and causes the cell membrane of the receptor to depolarize and generate a signal. This signal is then transmitted to the central nervous system to be interpreted through the sequential depolarizing and hyperpolarizing of the cell membrane as it travels down the nerve. Besides this general picture, nociceptive activity can be augmented by nociceptive sensitizing agents released by surround cells, such as cells damaged during an injury, (Argoff 2011). By releasing pro-inflammatory factors such as bradykinin, prostaglandin E2, nerve growth factor, and others, these mediators affect the membrane potential of the nocieptors and lower the threshold needed for activation (Argoff 2011). Studies show that glial cells, once thought of as only supporting cells, also have the ability to increase nerve excitability through the release of nociceptive sensitizing agents and thus also play a role in the initiation and maintenance of enhanced pain states (Argoff 2011).
As studies continue and greater understanding is gained, health professions are discovering more efficient ways to treat their patients and provide management practices. Recently, it has been found that, single analgesic therapies may be limited in their ability to comprehensively target certain mechanism and be effective in chronic pain management (Argoff 2011). Because of the complexity and variety of physiological mechanism involved, single-agent therapies are not optimal because they address a limited number of transmission and modulatory pathways (Argoff 2011). In comparison, multi-drug analgesic approaches take advantage of complementary mechanism to reduce pain and thus decrease the dosage needed and negative side affects (Argoff 2011). In a study involving post-surgery shoulder pain, it was found that combining ropivacain, morphine, and ketorolac reduced the incidence of nausea, lowered postoperative pain at rest and with movement, and reduced post-operative morphine consumption (Argoff 2011).
Still what are some difficulties that arise with the use multiple drugs? Why is this not implemented more when it comes to pain management?
Argoff, Charles. (2011). Review: Mechanisms of pain transmission and pharmacologic management. Current Medical Research and Opinion, 27, 2019-2031.
Pharmaceutical drugs and pain killers are many times referred to as controlled toxins. Obviously the more drugs taken the higher the risk of side effects or a bad combination of toxins can occur, so the least amount taken the better. I’ve seen a shoulder nerve block done while shadowing an anesthesiologist and have also experienced it. It was by far the best pain inhibitor because I couldn’t feel anything in my shoulder or arm the first 24 hours which is the most painful time following surgery. This helped reduce my intake of pain killers by the anesthesiologist utilizing a minimal amount of local anesthesia in the correct place. The anesthesiologist will penetrate the neck with a long needle that emits electrical pulses to see how the muscles contract to locate the correct spot. A local anesthetic will then be administered right around a bundle of nerves, and will completely block AP’s from occurring down the shoulder all the way to the fingers, and will cause complete numbness. This will keep the area numb for approximately 12-24 hours. The benefits are reduced amounts of general anesthesia, reduced risk of nausea, earlier intake of nutrients, great pain control, and usually aids in quicker discharge of the hospital. This nerve block can be utilized for other surgeries as well.
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While I agree, the use of techniques such as nerve block to manage pain is very useful in not only controlling pain, but also reducing the use of pain medication, I don't believe enough patients or physicians utilize such methods. I feel the majority of patients I've come in contact with do not want to explore alternative methods of pain control, but rely heavily on pain medications. This often time leads to abuse of the medication, and can lead to withdrawls if their physician is no longer willing to prescribe pain medications. This can bring on a whole other set of problems for both doctor and patient. On the other hand, I also see physicians too willing to prescribe pain medications, either because they are unwilling to explore alternative therapies and/or too busy/distracted/uninterested to really investigate the source of a patient's pain. So it's wonderful to continue investigating alternative methods to pain management, but they will continue to be ineffective until more physicians are persuaded to use them in their everyday practice.
ReplyDeleteSteven's point of utilizing nerve blocks and other alternative methods for pain management rather than turning to pharmaceutical drugs is an important point to make in regards to the medical world. This made me think of an experience I had while shadowing and oral surgeon, in which a female patient came in for an issue with jaw and tooth infections. She was going to have to have her tooth extracted. While the surgeon was informing the patient about the pending extraction and what the procedure would entail, she informed the surgeon that she used to have an addiction to analgesics, and she did not want to utilize any sort of pharmaceutical drugs beyond over-the-counter advil or aspirin.
ReplyDeleteThis procedure would cause the woman to be in excruciating pain. Would some sort of alternative pain management benefit this woman? She is the perfect illustration of how careful medical providers need to be in their over-prescription of drugs. Not only can dependency ensue, but this can cause trauma for later procedures.
Over the summer, I shadowed a D.O who specialized in chronic pain control he used to methods, which I did not see discussed in the blog, but seemed effective in his chronic pain patients. The methods were of particular interest because they did not use opiates or other forms of possibly addictive painkillers. Dr. Cheng used the off label designation of BOTOX to control pain in several of his patients. BOTOX works to control pain by blocking the neuromuscular junction mechanism for relief of spasm and by potentially altering neuropathic pain messenger systems by blockade of glutamate transmission at the post-ganglion receptor site and by modulating substance-P(Herskowitz). This method works effectively with relatively little side effects aside from the paralysis risk associated with Botox and the fact that BOTOX is costly due to its use in cosmetics. The other method Dr. Cheng implemented was requiring all of his patients to see a physiologist in conjunction with their pain treatment. His philosophy was that while some pain is genuine in its physiological causes, other pain is a manifestation of psychosocial issues. Thus, by treating both the physical and mental aspects of the patient, he has had a better outcome with chronic pain patients, especially those with addiction problems. This idea is mirrored in several studies that show treating pain as an illness rather than a disease and learning to manage it though counseling and self- evaluation proves to be a very effective method in alleviating pain(Roditi and Robinson). Furthermore, 63% of primary care visit are related to chief complaints of pain of some sort or another(Roditi et al). Therefore, it is important that future physicians understand the vast amount of treatment options for patients with pain of one type or another.
ReplyDeleteA. Herskowitz, Novel therapeutic agents: BOTOX (Botulinum Toxin Type A) treatment of patients with sub-acute low back pain: A randomized, double blind, placebo-controlled study, The Journal of Pain, Volume 5, Issue 3, Supplement, April 2004, Page S62, ISSN 1526-5900, 10.1016/j.jpain.2004.02.214.
Roditi Daniela, Robinson, Micheal. The role of psychological interventions in the management of patients with chronic pain. Psychol Res Behav Manag. 2011; 4: 41–49. Published online 2011 May 11. doi: 10.2147/PRBM.S15375