South Med J. 2006 Nov;99(11):1245-55. Links
Opioids for chronic nonterminal pain.Ballantyne JC.
Division of Pain Medicine, Massachusetts General Hospital, Department of Anesthesia and Critical Care, Harvard Medical School, Boston, MA 02114, USA.
[email protected]
This article first reviews the evidence for and against chronic opioid therapy. Evidence supporting the opioid responsiveness of chronic pain, including neuropathic pain, includes multiple randomized trials conducted over months (up to 8 months). Observational studies are conducted for longer, and many also support opioid analgesic efficacy. Concerns have arisen about loss of efficacy with prolonged use, possibly related to tolerance or opioid-induced hyperalgesia. Mechanisms of tolerance and opioid-induced hyperalgesia are explored. Evidence on other important outcomes such as improvement in function and quality of life is mixed, and is less convincing than evidence supporting analgesic efficacy. It is clear from current evidence that many patients abandon chronic opioid therapy because of the unacceptability of side effects. There are also concerns about toxicity, especially when opioids are used in high doses for prolonged periods, related to hormonal and immune function. The issue of addiction during opioid treatment of chronic pain is also explored. Addiction issues present many complex questions that have not been satisfactorily answered. Opioid treatment of pain has been, and remains, severely hampered because of actual and legal constraints related to addiction risk. Pain advocacy has focused on placing addiction risk into context so that addiction fears do not compromise effective treatment of pain. On the other hand, denying addiction risk during opioid treatment of chronic pain has not been helpful in terms of providing physicians with the tools needed for safe chronic opioid therapy. Here, a structured goal-directed approach to chronic opioid treatment is suggested; this aims to select and monitor patients carefully, and wean therapy if treatment goals are not reached. Chronic opioid therapy for pain has not been a universal success since it was re-established during the last two decades of the twentieth century. It is now realized that the therapy is not as effective or as free from addiction risk as was once thought. Knowing this, many ethical dilemmas arise, especially in relation to patients' right to treatment competing with physicians' need to offer the treatment selectively. In the future, we must learn how to select patients for this therapy who are likely to achieve improvement in pain, function and quality of life without interference from addiction. Efforts will also be made in the laboratory to identify opioids with lower abuse potential.
Best Pract Res Clin Anaesthesiol. 2007 Mar;21(1):65-83.Links
The impact of opioid-induced hyperalgesia for postoperative pain.Koppert W, Schmelz M.
Klinik für Anästhesiologie, Universitätsklinikum Erlangen, Krankenhousstrasse 12, D-91054 Erlongen, Germany.
[email protected]
Clinical evidence suggests that--besides their well known analgesic activity - opioids can increase rather than decrease sensitivity to noxious stimuli. Based on the observation that opioids can activate pain inhibitory and pain facilitatory systems, this pain hypersensitivity has been attributed to a relative predominance of pronociceptive mechanisms. Acute receptor desensitization via uncoupling of the receptor from G-proteins, upregulation of the cAMP pathway, activation of the N-methyl-D-aspartate (NMDA)-receptor system, as well as descending facilitation, have been proposed as potential mechanisms underlying opioid-induced hyperalgesia. Numerous reports exist demonstrating that opioid-induced hyperalgesia is observed both in animal and human experimental models. Brief exposures to micro-receptor agonists induce long-lasting hyperalgesic effects for days in rodents, and also in humans large-doses of intraoperative micro-receptor agonists were found to increase postoperative pain and morphine consumption. Furthermore, the prolonged use of opioids in patients is often associated with a requirement for increasing doses and the development of abnormal pain. Successful strategies that may decrease or prevent opioid-induced hyperalgesia include the concomitant administration of drugs like NMDA-antagonists, alpha2-agonists, or non-steroidal anti-inflammatory drugs (NSAIDs), opioid rotation or combinations of opioids with different receptor/selectivity.
The above are a couple of abstracts from pubmed. I copied and pasted them because I think that it is an important concept for patients to learn, that opiates can actually predispose you to more pain. There is a time for treating acute pain, like sickle cell disease, or kidney stone, and there is a time to be more conservative (chronic back pain).
A lot of the time, we get people with chronic pain who come to the ED seeking narcotics. They come for various claims, "My dog ate my prescription. My fibromyalgia is worse and I need IV demerol. I didn't keep my appointment with my PCP and now they won't see my in clinic for another 2 weeks and told me that if it was that bad, to come to the ED." If it is for chronic pain, that is being treated by a PCP, I try to find out where they messed up and make sure that they understand that chronic pain is best treated by one practitioner in one office and that repeated trips to the ED is not the ideal way to deal with chronic pain, and (if I've found inconsistencies in their story and they have numerous ED visits for similar complaints) that their behavior smacks of addiction and drug seeking. I emphasize the hyperalgesic effects of narcotics and try to get them to see that narcotics aren't the best answer for chronic pain.
I always try to give them the benefit of the doubt. If in my heart I think they are bogus and are seeking a high, I avoid giving them IV narcotics by telling them that the oral route is just as effective, will last longer, and will be less likely to be habit forming. (I don't know that this is true, but it sounds good to me).
If they have an acute complaint that sounds kind of bogus, I tell them that I think that OTC ibuprofen and tylenol seems like the best route to go with to me. If they beg, I usually cave and give them like 8 vicodin. If they want to waste 2-8 hours scoring a measly handful of vicodin, then they are stupid.
If they have what seems to be legitimate pain, I err on the side of compassion and give them 12-30 vicodin or percocet depending on the complaint and how long I think it will last.
