Review of Pharmacological Pain Management

Transcription

1 Review of Pharmacological Pain Management CHAMP Activities are possible with generous support from The Atlantic Philanthropies and The John A. Hartford Foundation

2 The WHO Pain Ladder The World Health Organization Pain Ladder outlines an overall strategy for pharmacological pain management as follows: Step 3: Severe pain (rated 7-10 ): Requires treatment with strong opioids, with or without the addition of a non-opioid or adjuvant medication. Step 2: Moderate pain (rated 4-6 ): May be treated with an opioid only, or an opioid combined with a nonopioid. Step 1: Mild pain (rated 1-3 ): Can typically be treated with nonopioids. 2 * on a scale of 0-10

3 Principles of Pharmacological Pain Management Key Points to Remember About the WHO Pain Ladder At each step in the pain ladder: The appropriate medication and dose is the one that controls pain with the fewest side effects. Medication choice is based on type and severity of pain and action and duration of medication(s). Frequent dose adjustment may be necessary to arrive at the appropriate dose to relieve pain. Around-the-Clock Dosing 3 Around-the-clock dosing is required with pain that is constant. If pain medication has to be administered every 4 hours, it is usually best to switch to long-acting formulations (like MS Contin) so the patient can sleep through the night without breakthrough. PRN dosing with short-acting, rapid-onset medications may be used along with around-the-clock dosing for breakthrough pain or activity-related pain.

4 Non-Opioid Analgesics Best Choice for Mild to Mild-Moderate Pain Non-opioid analgesics are the best choice for mild pain, or for mild to moderate pain, alone or in combination with opioids. The most common non-opioid pain relievers are acetaminophen, aspirin, and other non-steroidal anti-inflammatory drugs (NSAIDs) Use of these drugs is limited by a ceiling effect higher doses do not relieve pain beyond a certain dose level. Older patients taking NSAIDs should be monitored for adverse effects, including renal and hepatic dysfunction, bleeding, and gastric ulceration 4

5 Non-Opioid Analgesics Using Non-Opioids in Older Adults Many non-opioid analgesics carry a risk of toxicity above the recommended maximum daily dose. The recommended daily dose is further reduced in older adults, particularly those with hepatic dysfunction, or those at risk for GI bleeding and cardiovascular problems. For example, the maximum daily dose of acetaminophen for healthy younger adults is 4000 mg; in older adults with hepatic dysfunction it may need to be reduced by 50-75%. 5

6 Non-Opioid Analgesics NSAIDs: Monitor for Complications Teach the patient to: Promptly report blood in vomit, urine or stool; or black tarry stools. Report signs/symptoms of liver toxicity, including nausea, lethargy, itching, jaundice, RUQ tenderness and flu-like symptoms. Check with his or her physician or home care nurse before taking additional medication. 6

7 Opioid Medications Best Choice for Moderate to Severe Pain Moderate pain (rated 4-6 on a scale of 0-10) may be treated with an opioid. Moderate pain may also require an opioid combined with a non-opioid, but remember, combination regimens may be limited because of the maximum daily dose of the non-opioid. Examples: Hydrocodone, Oxycodone Severe pain (rated 7 and above on a scale of 0-10) requires treatment with strong opioids. Examples: Morphine, Hydromorphone, Oxycodone, Fentanyl 7

8 Opioid Medications Opioid Medications to Avoid with Older Adults (3.2) Meperidine (Demerol): A metobolite produces CNS toxicity that may cause tremor, irritability, cognitive changes and seizures; other opioids are safer and more effective. Propoxyphene (Darvon, Darvocet): Long half-life, metabolite cause CNS and cardiac toxicity; can cause renal injury; analgesia equal to aspirin or acetaminophen; other opioids are safer and more effective. Pentazocine (Talwin ): Causes delirium and agitation in older patients, potential for renal injury; other opioids are safer and more effective : Assessment for High Risk Medications in the Elderly

9 Opioid Medications A Peripheral Analgesic: Lidocaine Patches Although not technically an opioid medication, a newer agent, the topical lidocaine patch 5% (Lidoderm), may be useful for older patients with postherpetic neuralgia (PHN). PHN is a chronic pain syndrome that presents as continuous burning or intense paroxysmal pain which may be severe and disabling. The lidocaine patch is targeted peripheral analgesic, so it does not have the same adverse systematic effects possible with opioids and other medications. It also has a minimal risk of drug/drug interactions. 9

10 Opioid Side Effects Start Low, Go Slow Opioids should be started at low doses and titrated up gradually to reach the point of maximum pain relief with minimum side effects. In older patients, the starting dose is usually lowered. You may have heard this approach described as Start low, go slow. 10

11 Opioid Side Effects Tolerance Tolerance usually develops to many of the side effects of opioids in a few days. Tolerance to the analgesic effect can also develop and may require additional medication over time. If a patient with previously-controlled pain is no longer getting adequate relief, an assessment of worsening pain and disease progression should also be considered. 11 Physical Dependence Physical dependence (as opposed to addiction) is a normal and expected response to continuous opioid therapy Physical dependence is characterized by withdrawal symptoms experienced when an opioid is discontinued. Symptoms may include agitation, insomnia, diarrhea, sweating, and rapid heart beat. If pain is resolved, physical dependence is easily treated by gradually decreased the opioid dose.

12 Opioid Side Effects Common Side Effects and Monitoring for Complications Drowsiness and Nausea Drowsiness and nausea typically resolve in 1-3 days without treatment. Patients and their families should be instructed that these may occur. Rarely, patients may experience confusion or fuzzy thinking, which can be persistent. This can continue to delirium for reasons that are not clearly understood. Any change in mental status with a new opioid or change in opioid dose should be reported to the physician. 12 Respiratory Depression It is the first dose of an opioid that puts the patient at most risk for developing a respiratory event. After that, there is rapid central nervous system tolerance to the respiratory depressive effects of opioids. However, patients with other respiratory risk factors (including alcohol use and pre-existing respiratory disease) should also be monitored closely with opioid dose increases.

13 Opioid Side Effects Common Side Effects and Monitoring for Complications con t Constipation While many of the side effects of opioids resolve in a few days, constipation almost never resolves on its own while the patient is still taking an opioid. Constipation usually occurs after several days of taking opioids, can be quite painful, and may require hospitalization. Constipation should always be anticipated and treated aggressively. All patients taking around-the-clock opioids should have a prophylactic bowel management plan, including appropriate medications. Stool softeners, by themselves, are usually insufficient. In the absence of adequate fluid intake, bulk laxatives such as psyllium (Metamucil) can cause fecal impaction and should be avoided. Pseudo-addiction In pseudo-addiction, patients with severe unrelieved pain can become intensely focused on obtaining relief, and their behavior can mimic aspects of drug seeking behavior. This behavior should resolve when adequate pain relief is provided, without the evidence of loss of control, escalating, and binging that is characteristic of addiction, 13