Avoiding trouble when using opiates to treat patient pain
By Jason van Steenburgh
SAN DIEGO—You're treating a patient suffering from acute pain, but you're concerned about giving too much morphine. In general, you tend to administer no more than 5-10 mg of the drug every four hours, but the patient is still complaining of pain.
According to speakers at two Annual Session presentations on pain management, the above scenario is all too common—and it points to what's wrong with the state of pain care. Because many physicians either don't know how—or are afraid to—prescribe the right dose of opiates to control pain, patients suffer.
Michael E. Preodor, FACP, a hospice physician and president of Horizon Hospice in Chicago, said that data show that many physicians can do a better job when it comes to alleviating pain.
According to the Study to Understand Prognoses and Preferences for Outcomes and Risk Treatments (SUPPORT), a study on end-of-life care published in the Nov. 22, 1995, Journal of the American Medical Association, about half of patients who die in U.S. health care institutions end their lives in unrelieved pain.
Dr. Preodor and other speakers acknowledged that physicians face serious issues when it comes to prescribing opiates. Legitimate worries include not only fears about addicting patients to painkillers, but concerns about sanctions for overprescribing the drugs.
Speakers at the meeting, however, gave tips to help physicians aggressively manage pain using all means at their disposal, especially opiates. Their strategies focused on setting appropriate dosages, minimizing side effects and avoiding trouble with local medical boards.
New thinking about dosing
During his presentation, Dr. Preodor said that new ideas about pain began to alter practice patterns about 20 years ago. Instead of viewing pain as a symptom of disease or injury, he explained, physicians began to view it as a problem in its own right.
Not so long ago, for example, traditional thinking held that patients could handle only limited quantities of morphine, a premise known as the ceiling effect. When the AMA brought experts together in 1999 to design a curriculum to instruct physicians on pain management, however, they repudiated the ceiling effect.
Learning modules produced by the AMA's Education for Physicians on End-of-Life Care project say that if patients are suffering from mild to moderate pain, you should increase their morphine dosage by 25% to 50% per day. If patients are in severe or uncontrolled pain, the modules say, raise the dosage by 50% to 100% per day.
Dr. Preodor outlines other ways that pain management strategies have changed over the years by contrasting old and new ways of thinking:
Old: Treat patient pain only when patients rank it 10 on a 10-point scale.
New: Anticipate pain and treat it before it reaches unacceptable levels (usually between four and six on the 10-point scale).
Old: Give a maximum of 10-15 mg of morphine per hour.
New: Use whatever is needed to treat pain.
Old: Use only morphine or another opiate for pain.
New: Use multiple medications and combine morphine with adjuvant medications for better pain control.
Act vs. react
Old: Administer treatment "as needed" when patients report pain symptoms.
New: Use a steady-state treatment and build up a steady level of narcotics to provide complete relief.
Old: Use short-acting preparations.
New: Combine longer-release medications with short-acting preparations for incidents of breakthrough pain.
Physicians often know how to use opiates effectively, but some shy away from the drugs because they worry about side effects and addiction. Jay A. Jacobson, FACP, chief of the medical ethics division for the department of internal medicine at the University of Utah School of Medicine in Salt Lake City, addressed the classic dilemma of respiratory depression during another Annual Session presentation.
Dr. Jacobson said that while physicians tend to worry about respiratory depression in any patient who receives high doses of opiates, relatively few patients will actually experience this problem. He did identify, however, several groups of patients who may be more prone to problems as a result of taking opiates.
You should watch patients who have just had a procedure to relieve pain and still have significant amounts of opiates in them. "If patients still have lots of opiates in their body but their pain has been removed," Dr. Jacobson warned, "that can produce respiratory depression."
That doesn't necessarily mean that you should start to wean patients off opiates before a procedure to relieve pain. Dr. Preodor, for example, suggested taking patients off opiates after the procedure has been deemed a success and monitoring them closely. If they develop any problems, he said, be ready to give them a narcotic-reversing agent like naloxone.
Dr. Preodor also suggested giving chronic opiate users 25% of their normal daily dose of opiates to help ward off withdrawal symptoms. That relatively small amount in a tolerant patient should not place them in any danger of respiratory depression, he said.
Another group of patients you should track closely when giving pain killers: individuals who have rarely or never received opiates. Because these individuals are not tolerant, Dr. Preodor said, you should worry about the possibility of respiratory depression when administering a sizeable dose of an opiate. Remember, he added, that a 70 kilogram patient should safely tolerate a 10 mg intravenous dose of morphine without undue risk.
If you're treating patients who have used opiates in the past or who use them chronically to control pain, on the other hand, respiratory depression is not as important. Dr. Jacobson said that these patients often become tolerant to the drugs' side effects. As a result, he added, these patients are typically unaffected by the drugs' tendency to depress respiration.
To give an example, Dr. Preodor recalled a patient who was receiving 10 mg of morphine per hour but mistakenly received 250 mg in just over an hour. A sitter monitored the patient through the night to make sure she suffered no ill effects, and the patient was fine. (Her main comment was that she had never slept better.)
While the case was extreme, it shows that patients who are used to opiates and their side effects can handle much higher doses of the drugs without many of the negative side effects. If the patient was unaccustomed to opiates, Dr. Preodor said, the incident could have turned out badly.
Somnolence and confusion
For many physicians, somnolence and confusion are even more troubling side effects of opiates. While these concerns typically take a back seat to acute pain, they tend to be an issue for patients who don't have long to live and want to remain alert during their last days.
While physicians struggle to balance cognitive function with pain relief, Dr. Preodor said that the confusion opiates cause sometimes leads family members to criticize their use. "They say things like, 'Grandma was never the same after they gave her all that morphine,' " he explained.
To keep confusion in check, Dr. Preodor recommended starting patients on narcotics slowly and using low doses when possible. Although confusion and mental changes will normally clear up in 48 to 72 hours as patients adapt to the drugs, some patients don't have that long to live. If death is near, patients may want to sacrifice clarity in exchange for pain relief.
Because our society is concerned about addiction, Dr. Preodor said, many physicians are concerned about giving narcotics to their patients. But studies show that patients who have no previous history of drug abuse rarely become addicted to opiates in the health care setting.
Speakers at both sessions cautioned physicians not to confuse addiction with tolerance or physical dependence. Addiction is a psychological phenomenon, while tolerance and physical dependence are physiological responses.
When patients take opioids over a period of time, their bodies may respond less and less to the drugs' effects as they develop tolerance. They may also experience a rebound effect or withdrawal when the dose is cut because they have developed physical dependence.
Addicted patients, on the other hand, compulsively use drugs to achieve a psychic effect. They crave drugs to relieve emotional pain more than physical pain.
'When a patient's pain hasn't been controlled for several hours, you bet she's watching the clock!'
—Michael E. Preodor, FACP
Monitoring patients for drug-seeking behavior is important to make sure that your patients are not becoming addicted, but Dr. Preodor warned physicians not to be fooled by "pseudo-addiction." Patients who aren't receiving enough medication for their pain will sometimes become anxious, ask for the drug, ask for higher doses and even watch the clock.
While you may think such behavior indicates an addicted patient, it could just be a sign that the patient is still in pain. "When a patient's pain hasn't been controlled for several hours, you bet she's watching the clock!" he said.
Dr. Jacobson also stressed that the possibility of addiction during end-of-life care should not be a barrier to treatment. He said that because dying patients typically have a well-documented source of pain, physicians are protected legally.
While physicians may worry about the legal fallout if their patients develop an addiction to opiates, the bigger danger is prescribing to known or suspected addicts.
"Prescribing to known addicts is one thing that can definitely get you into trouble with a licensing agency," said Ronald C. Agresta, MD, president of the Federation of State Medical Boards, the umbrella organization of state licensing boards.
To avoid legal troubles, Dr. Agresta says physicians should follow up regularly with patients taking opioids and keep detailed documentation.
While physicians may legitimately fear being deceived by drug-seeking patients, Dr. Agresta said that as long as you follow some common-sense recommendations, you should never have to worry about actions from your regulatory board. He suggested the following steps:
Keep accurate records, note your intentions and plans for treatment, and include as many details as possible.
Monitor and evaluate patients on a regular basis. Prescribing without follow-up is asking for trouble.
Stop prescribing if pharmacists warn you that a patient is receiving multiple prescriptions for medications from other physicians. Dr. Agresta said that pharmacists often go directly to the Drug Enforcement Administration or the police if you ignore their warnings.
Avoid prescribing for yourself or your immediate family. Although medical boards do not consider it as much of an automatic infraction as in the past, you will still get their attention.
Have patients sign an informed consent form and keep it on file.
Show that you are willing to refer your patients to pain specialists and addictionologists when patients show signs of addiction such as losing prescriptions or requiring escalating dosages that are not consistent with their condition or treatment plan. Dr. Agresta pointed out that documenting difficulties and enlisting the help of experts will help absolve you if there is an investigation.
To help ease physicians' fears that regulatory agencies and licensing boards are looking for an excuse to investigate opiate prescribing patterns, Dr. Agresta noted that state medical boards typically initiate investigations only in response to a complaint. They are not policing organizations that look at prescribing patterns without cause.
Dr. Agresta said that while working for the state medical board of Ohio, he saw a drop in prescribing violations for controlled substances. He explained that this reflected a nationwide trend in the licensure community to change how it deals with physicians who treat pain. Most medical boards now encourage education about pain management rather than suspension or license revocation.
Dr. Agresta said that many medical boards use the "Model Guidelines for the Use of Controlled Substances for the Treatment of Pain" from the Federation of State Medical Boards. The guidelines, which acknowledge the important role opiates play in pain management, were designed to alleviate physician uncertainty and encourage better pain treatment. (The guidelines are available online.)
More than half of patients who die in hospitals suffer from unrelieved pain, largely because many caregivers are afraid to aggressively use powerful opiates like morphine. A chief concern? Patients who take morphine over an extended period of time can develop toxicity.
At an Annual Session presentation, however, internist Michael E. Preodor, FACP, gave tips on how to spot patients who may be developing morphine toxicity. He also gave pointers on how to safely switch those patients to methadone.
Dr. Preodor, president of Horizon Hospice, a palliative care center in Chicago, said that while most patients have no upper limit for morphine use, some will develop morphine toxicity at high doses. The condition, he said, is characterized by delirium, twitching and escalating pain.
While switching these patients to methadone is a good strategy, he warned that you have to be careful. Methadone has a long half-life, Dr. Preodor said, so it remains in the patient's system for a relatively long time. The up side, however, is that it often brings renewed pain relief at much lower doses.
When switching patients from morphine to methadone, many textbooks suggest giving half as much methadone. If you're giving a patient 2 mg of morphine, for example, you should convert that to 1 mg of methadone.
While that may seem like a simple enough formula, Dr. Preodor cautioned that it is correct only at low doses. For patients receiving higher doses of morphine, the conversion ratios are nonlinear.
If your patient receives 300 mg of morphine orally per day, for example, you would use a conversion ratio of 8-1. If your patient receives more than 1,000 mg of oral morphine per day, you would use a conversion ratio of about 10-1 or 20-1.
Because these dramatic conversion ratios allow you to reduce a patient's narcotic load, Dr. Preodor said, methadone is a much better alternative than other narcotics, which allow you to reduce the drug load by only about 33%.
He warned, however, that methadone conversion can be difficult because the drug lingers in the system much longer than morphine. The half-life of morphine is only four hours, compared to the 12- to 58-hour half-life of methadone. (Researchers have found that for some patients, the half-life of methadone can be up to 200 hours.)
Dr. Preodor noted that this wide variance presents some challenges. For instance, he said that he doesn't recommend changing doses more often than once every five days.
The AMA has released the first of four free, self-study CME modules on pain management.
The first module, "Pain Management: Overview of Physiology, Assessment and Treatment," addresses barriers to pain management, comprehensive pain assessment and both pharmacologic and nonpharmacologic treatment strategies.
Later modules are scheduled to address pain in children, older adults, certain ethnic groups, substance abusers, cancer patients and the dying. You can order the program online.
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