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PAIN MANAGEMENT Option Care

CEP-05 Pain Management 110515 of 31 © 2015 Option Care. All Rights Reserved

PAIN MANAGEMENT

CLINICAL EDUCATION PROTOCOL

Latest Revision: 06/01/09

Updated Date: 04/20/10 rebranded

Rebranded to Option Care: 11/05/2015



TABLE OF CONTENTS

I. INTRODUCTION ............................................................................................................................ 4

A. Purpose ............................................................................................................................ 4 B. Definition .......................................................................................................................... 4 C. Diagnoses ......................................................................................................................... 4 D. Classification of Pain…………………………………………………………………………….. 5

1. Acute Pain ............................................................................................................ 5 2. Chronic Pain .......................................................................................................... 6

E. Tolerance, Physical Dependence and Addiction

II. PAIN ASSESSMENT ..................................................................................................................... 7 A. Initial Assessment ............................................................................................................. 7 B. Follow Up Assessment ...................................................................................................... 8 C. Assessment Tools……………………………………………………………………………... 8

III. BASIC PRINCIPLES OF PAIN MANAGEMENT…………………………………………………… . . 9

A. Non-Pharmacological Pain Management ......................................................................... 9 1. Physical Interventions ........................................................................................... 9

2. Cognitive Interventions 3. Other Interventions ............................................................................................... 9

B. Pharmacological Treatment of Pain ................................................................................... 9

1. Analgesic Ladder .................................................................................................. 9 2. Non-Opioid Analgesics 3. Opioid Analgesics ............................................................................................... 11 4. Principles of Oral Opioid Administration…………………………………………… 15 5. Opioid Switching………………………………………………………………………..15

C. Routes and Modes of Administration ............................................................................... 15 1. Oral Administration ............................................................................................. 15 2. Intramuscular Administration ............................................................................... 15 3. Subcutaneous Administration .............................................................................. 15 4. Intravenous Administration………………………………………………………...… 16 5. Intraspinal Administration …………………………………………………………..16 6. Miscellaneous Agents………………………………………………………………… 18

a. Topical. ……………………………………………………………………… 19 b. Rectal……… ………………………………………………………………… 19 c. Transmucosal ……………………………………………………………… 19 d. Intranasal ............................................................................................... 19 e. Inhalation ..…………………………………………….....………………… .19 f. Transdermal ………………………………………………………………...20

D. Analgesic Adjuvants …………………………………………………………………………….20 1. Tricyclic Antidepressants ..................................................................................... 20

2. Antihistamines ................................................................................................... 21 3. Corticosteroids ................................................................................................... 21

4. Psychostimulants……………………………………………………………………….21 5. GABA-B Receptor Agonists ………………………………………………………... 22 6 Anti-Anxiety Agents…………………………………………………………………….22 7. NMDA Receptor Antagonists. .............................................................................. 22 8. Anticonvulsants ................................................................................................... 22

E. Opioid Antagonists ………………………………………………………………………………. 22



IV. DRUG ADMINISTRATION ............................................................................................................ 23 A. Equianalgesic Dosing........................................................................................................ 24 B. Titrating Opioids ................................................................................................................ 24 C. Management of Adverse Effects ....................................................................................... 24 1. Constipation ......................................................................................................... 24 2. Nausea and Vomiting ........................................................................................... 24 3. Sedation …………………………………………………………………………… …25 4. Respiratory Depression……………………………………………………………… 25 5. Itching ………………………………………………………………………………… 26 6. Urinary Retention ……………………………………………………………………….26

V. PAIN MANAGEMENT IN THE PEDIATRIC AND GERIATRIC POPULATION…………………… 26

A. Consideration in treating Pain in Children .....................................................................… 26 B. Consideration in treating Pain in Geriatric Patients ……………………………………… .27

VI APPENDIX A - PAIN RATING SCALES 29

1. Wong-Baker Faces Rating Scale ...................................................................................... 29 2. FLACC Pain Scale……………………………………………………………………………….30

VII. APPENDIX B- INTERNET BASED SOURCE OF PAIN MANAGEMENT…………………… 31 VIII. BIBLIOGRAPHY ............................................................................................................................ 32



I. INTRODUCTION

Pain affects people of all ages, racial and ethnic backgrounds. In the past, many patients went

undertreated for pain. Today, there is much greater awareness among healthcare professionals of the need to address pain.

A. Purpose The purpose of this monograph is to provide Homecare Clinicians with knowledge of the current practice guidelines for the safe and effective management of pain in the alternate care settings. The

primary focus is: - Patient Assessment Methods - Basic Principles in Pain Management - Pharmacologic Treatment for Chronic, mainly cancer related, pain - Parenteral administration in the alternate site setting.

Patients and heath care professionals can find a wealth of information on pain treatment from various professional organizations. Links to their website can be found in Appendix B.

B. Definition

Pain may be defined as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”. (2) This well-accepted, broad-based definition, advanced by the International Association for the Study of Pain, recognizes pain as a complex experience that may involve physical injury to tissue, but is also comprised of emotional and psychological influences.

Margo McCaffery RN, MS, FAAN defines pain as "whatever the experiencing person says it is, existing whenever he/she says it does." (6) This definition recognizes pain as a subjective and personal experience that depends not only on the characteristics of the underlying physical disorder, but also on the meaning ascribed to the experience.

C. Diagnoses

The most common type of pain seen in the alternate site setting is pain secondary to cancer. However, patient needing pain management may present with a variety of other diagnoses. These include, but are not limited to, the following:

Abdominal Pain/Irritable Bowel Syndrome, Somatic Pain

Amputation

Back, Neck, Leg pain

Headaches and Migraines

Neuropathic Pain

Orthopedic Pain

Degenerative Joint Disease, Rheumatoid Arthritis, Osteoporosis

Post surgical pain

Cancer related pain can be caused by (1)

Direct invasion of tumor into soft tissues, bone or nerves

Effects of cancer treatment, i.e. surgery, chemotherapy or radiation.



D. Classification of Pain (2) Multiple systems for classifying pain exist and are based on a variety of factors such as the pain’s characteristics, its duration and underlying pathophysiology. While a detailed discussion is beyond the scope of this monograph, a summary of some key concepts in the classification of pain follows. 1. Acute Pain

The feeling of pain involves a complex array of neural networks in the brain that are acted upon by incoming stimuli to produce the feeling of pain in response to tissue damage. In acute pain, this feeling is relatively short lived (less than 3 months) and while tissue injury can be substantial, the injury does not overwhelm the body’s ability to repair itself. Usually acute pain declines within days to weeks of injury and often terminates even before tissue healing has occurred. Acute pain may be of sudden or slow onset and the intensity may range from a simple pin prick to a traumatic amputation of a limb. Acute pain may originate from a somatic source (skin, muscle bone, joint, connective tissue) or it can originate from an internal organ such as the liver or pancreas (visceral pain). Acute pain may be expressed with objective signs such as grimacing, moaning, and rubbing of the painful area. Examples of acute pain are: pain resulting from a bone fracture or postoperative pain. Patients with acute pain can usually describe its exact location and quality. Somatic (skin, bone, joint etc.) pain is usually described as sharp, aching, throbbing or pressure-like. Visceral pain is described as gnawing, cramping, aching or throbbing. Both types of acute pain (somatic and visceral) fall under the classification of nociceptive pain. Most nociceptive symptoms usually respond to simple analgesics (nonsteroidal anti-inflammatory agents (NSAID’s), acetaminophen and opioids.

2. Chronic Pain When acute pain continues for a duration greater than 3 months, or when structural or neurological changes occur that become irreparable and perpetuate pain,

chronic pain develops. The sensations associated with chronic pain are often described as burning, aching, electrifying, shooting, lancinating or radiating and they may be exaggerated or disproportionate to the original pain, or occur long after the damaged

tissue has healed. Therefore, it is not solely the duration of time that distinguishes acute from chronic pain but rather the body’s ability to repair itself.

Patients suffering from chronic pain may also present with a variety of psycho-social issues such as:

Decreased ability to perform activities of daily living

Sleep disturbance

Social isolation, intimacy and relationship issues

Depression, anxiety, anger, loss of self esteem

Societal issues such as lost work days, increased healthcare costs and disability

Chronic pain can be divided into two categories: nociceptive and neuropathic. Most patient’s suffering with chronic pain present with both components.

o Nociceptive: Pain that results from injury to skin, bone, muscle, etc. It is often described as sharp, dull, aching, or throbbing.

Neuropathic: Pain that is caused by damage to nerves or pathologic changes in the pheripheral or central nervous system. For example, Phantom limb pain, complex regional pain syndrome, chemo induced, multiple sclerosis or parkinson related pain.



E. Tolerance, Physical Dependence, and Addiction (1)

One of the main barriers to more adequate control of pain is a failure to distinguish between tolerance, physical dependence and addiction. Tolerance and physical dependence are inevitable with chronic opioid use. They are pharmacologic properties and must not be confused with addiction, which is a psychological syndrome that rarely occurs following medical exposure. Tolerance

Tolerance is where the body adapts to constant exposure to a drug. Changes result in a decrease of the drug’s effects over time. To overcome the changes, increased dose of a drug is needed to achieve the same pharmacologic effect.

Tolerance should not be a barrier to the maintenance of pain control. It usually can be managed by simply increasing the dose. The presence of drug tolerance does not imply addiction; therefore, clinicians should be cautioned about reacting negatively to the number of milligrams in a dose and begin to focus on the patient’s response to that dose. More importantly, the following questions must be considered at each assessment:

Are there side effects to the treatment?

Are these side effects dangerous or unacceptable to the patient?

Is the intensity of pain (as rated by the patient on an appropriate pain scale) satisfactory to the patient?

Dosage increases are usually well received as patients may become tolerant to opioid side effects over time. It is worth noting that some patients may become tolerant to some of the effects of the drug while remaining unaffected by the other effects. An alternate strategy to managing tolerance involves the substitution of another similar opioid.

Physical dependence

Physical dependence refers to a condition in which the abrupt discontinuation of a drug or the administration of an antagonist produces symptoms of of physical withdrawal (abstinence). It is an involuntary and inevitable physiologic phenomenon and is unrelated to addiction. The dose should be tapered down in 25-50% increments to help prevent withdrawal. Signs and symptoms of withdrawal differ among the classes but with respect to opioids they include: diarrhea, agitation, runny nose, sleeplessness, irritability, sweating, abdominal cramping, muscle spasms and piloerection (the hairs on arms and legs stand upright). While dependence is commonly used in reference to the opioids, it is also applicable to drugs in other classes for which abrupt withdrawal is problematic. These include beta-adrenergic blockers, antidepressants corticosteroids, and anticonvulsant agents. Addiction Addiction is a behavior of overwhelming involvement with obtaining and

using a drug for its psychological effects, not for approved medical reasons. It is characterized by behaviors that include one or more of the following:

Impaired control over drug use

Compulsive drug use

Continued drug use despite harm and craving.



Most patients discontinue opioid use when the pain stops: however, about one percent of patients have a high tendency to relapse back to continuing the drug use once the pain is gone. Addiction rarely occurs when a person takes opioids solely for pain relief on a mutually agreed-upon schedule and with proper monitoring by a healthcare professional.

II. PAIN ASSESSMENT

A comprehensive assessment is essential to ensure proper pain management. Since pain is inherently subjective, a patient’s self-report of pain is the current standard of care for assessment (1)

The assessment process is challenging component of any pain management plan. A multidisciplinary approach to patient assessment provides the patient with optimal outcomes; therefore include as many healthcare professionals involved in the patients therapy as possible (i.e., physician, nurse, pharmacist, counselor, etc.) as well as the patient. A comprehensive assessment(s) should be conducted:

Initially

At regular intervals after initiation of therapy

After each report of pain

At a suitable interval after pharmacologic or non-pharmacologic intervention (i.e., 15-30 minutes after initiation/change in parenteral therapy or one hour after oral administration).

A. Initial Assessment

The initial assessment of all patients provided treatment in the alternate site must include the following:

Detailed history of past and current medications

Physical examination

Psychosocial assessment With patients admitted for pain management the goal of the initial assessment is to characterize the pain by location, intensity and etiology. Utilize the Assessment Tools that have been adopted by your facility. The essential portion of the assessment is the patient’s self report; therefore, allow the patient to describe:

Location: Ask the patient to indicate where the pain is on the body or use a body diagram. Ask the patient if the pain radiates to other areas of the body.

Intensity: Ask the patient to rate the pain using a scale of 0-10 with 0 being no pain and 10 being the most severe pain or refer to other pain scales. Encourage the patient/caregiver to maintain a log of the pain intensity to report during follow up visits and telephone contacts.

Characterization: Listen to the patient’s description and quality of the pain. Date of onset (acute or chronic); intermittent or constant? Does the patient describe pain as sharp, dull, aching, throbbing, sharp, shooting, burning, twinge, etc.?

Aggravating and relieving factors: Ask the patient when he/she experiences the most pain and the least pain. What relieves the pain?

Cognitive response to pain: The clinician will have to note behavior in cognitively impaired patients or those who have communication problems.



Use appropriate pain assessment tools or ask a family member or caregiver to act as a translator. See section C below. Of particular importance is the historical use of pain medications and or treatments and their

associated efficacy and toxicity information. It is useful to know whether patient’s previous pain management is/was consistent with the treatment guidelines. If not, understanding the contributing factors will be important. Previous response, or lack there of, is often a predictor of future response.

Goals for pain control: Document the patient’s goals for pain control (through the use of scores on a pain scale) to be implemented in an appropriate pain management plan for the patient. An explanation of the common pain scales will be discussed later in this module.

B. Routine Follow Up Assessment

Ongoing pain assessment is crucial to an appropriate pain management plan. Changes in the pattern or the development of a new pain must trigger diagnostic evaluation and possible modification(s) in the treatment plan.

Subsequent pain evaluations must also include the area affected for the purpose of comparisons with the initial pain. Patients will frequently have two or more sources of pain. When the most significant pain is treated, other sources may be unveiled; therefore, as the patient’s treatment varies, continuous evaluation of the pain source is necessary to allow for appropriate therapy.

C. Assessment Tools Assessment of pain and severity are key factors in determining effective pain management. Adequate assessment is an essential component

to developing an understanding of the patient's experience of pain and is a pre- requisite for initiating a treatment plan that will meet mutually shared goals for

pain relief.

The most common assessment tool utilizes the numeric pain rating scale. The numerical scale utilizes numbers ranging from 0 to 10, with 0 illustrating no pain, and 10 reflecting the worst pain a patient has. Patients are initially asked to identify their own acceptable level of pain and are then asked to rate the intensity of their pain regularly using this scale. Employing a tool that quantifies the patients experienced level of pain at any given time in their treatment, enables the clinician to determine realistic goals for their pain management and determining how well the patient is progressing. A common rating scale for children is the Wong/Baker Faces Rating Scale. (Appendix A) This tool utilizes faces to represent a pain level, allowing a child to indicate how they feel. For children or adults who cannot communicate verbally, their pain rating must be made by observation of physiological signs and non-verbal behavior (i.e., crying, heart rate changes, facial expressions The FLACC Pain Scale (Appendix A) allows assessment of pain in based on non-verbal gestures or body actions, allowing for appropriate treatment.

Regardless of the pain scale utilized, it must be individualized based on the given patient’s physical, emotional, developmental, and cognitive needs.



III. BASIC PRINCIPLES OF PAIN MANAGEMENT

A. Non-Pharmacological Pain Management There are a variety of non-pharmacological approaches to managing pain. These approaches may

be used independently to provide analgesia, but most often are used as adjunct techniques to supplement the effects of more traditional pharmacologic treatment. For further information refer to the American Pain Society and National Cancer Institute website listed in Appendix (B).

1. Physical Interventions

a. Heat pads or cold pack applications b. Massage, Pressure, and Vibration c. Exercise d. Repositioning of immobilized patients to maintain correct body alignment and prevent

pressure ulcers. e. Immobilization of factures, or injured limbs and joints f. Stimulation Techniques: Transcutaneous Electrical Nerve Stimulation (TENS) or

Acupuncture.

2. Cognitive Interventions a. Relaxation and Imagery b. Hypnosis c. Cognitive Distraction and Reframing d. Patient and Family Education e. Psychotherapy, Structured Support Groups, etc.

3. Other Interventions

a. Radiation of the tumor b. Radio Frequency Ablation of the tumor c. Surgery of the tumor d. Nerve Blocks e. Neurologic Interventions

B. Pharmacologic Treatment of Pain

Pharmacological approaches to pain management include the use of the non-opioid and opioid analgesics and adjuvant medications. The route of administration depends on the patient's disease state and patient status.

1. Analgesic Ladder (13) The World Heath Organization (WHO) has described a three-step analgesic ladder as the framework for pharmacology pain management. It involves a stepped approach based on the severity of the pain. Clinicians must select the most effective analgesic with the fewest side effects, aim for the simplest dosing schedule, and dispense the medication via a route that is the least invasive first. Substitution of drugs within a category must be tried before switching therapy.

To maintain freedom from pain, drugs should be given “by the clock”, such as every 4-6

hours, rather than “on demand”. This three-step approach of administering the right drug in the right dose at the right time is basic frame work for pain control. Most cancer pain patients will require Step 2 or 3 analgesic. (13)



Step I: Patients with mild pain (1-3/10) should be treated first with a non-opioid drug (i.e. acetaminophen or a non-steroidal anti-inflammatory) unless there are contraindications to therapy (i.e., sensitivities, gastropathy, bleeding tendencies).

Treatment may be supplemented with an adjuvant drug, if indicated. This usually refers to the use of an antidepressant or anticonvulsant for neuropathic pain. (Refer to the section - Adjuvant Medications)

Step II: Patients suffering with persistent or increasing moderate Pain (4-6/10), should progress in treatment with the addition of a weak opioid (i.e., codeine, oxycodone, or hydrocodone) The opioid component of treatment must be administered around-the-clock (rather than on an as needed or symptomatic basis), with caution to avoid acetaminophen or aspirin toxicity. Step III: For persistent or increasing severe pain (7-10/10), treatment should progress to the administration of a potent opioid (i.e., morphine, hydromorphone, fentanyl, methadone, or levorphanol). The potent opioid should be administered around-the-clock (rather than on an as needed or symptomatic basis) to control basal pain, and supplemented with a short-acting Step II or Step III opioid, on an as needed basis for breakthrough pain. Alternate routes must be considered if the oral route proves ineffective or cannot be effectively utilized.

Patients may access the ladder at any tier and/or progress through the ladder rapidly if necessary to avoid prolonged periods of uncontrolled pain.

2. Non-Opioid Analgesics [4]

Non-opioid analgesics include acetaminophen, aspirin and other salicylates, and non-steroidal anti-inflammatory agents (NSAIDs). Acetaminophen produces its analgesic effect by inhibiting prostaglandin synthesis in the central nervous system. Acetaminophen does not inhibit cyclooxygenase activity; therefore, it is not an anti-inflammatory agent, nor does it interfere with platelet function or cause ulcers. It is rapidly absorbed following oral administration with peak plasma levels seen 30-60 minutes post ingestion. It is metabolized via the liver by hydroxylation and conjugation to inactive metabolites and can cause hepatotoxicity; therefore, it must be used with caution in patients with liver disease, malnutrition, and chronic alcoholism. The maximum dose of acetaminophen in a healthy adult is 4000mg per 24 hours. Nonsteroidal Anti-Inflammatory Agents (NSAIDs) act by inhibiting prostaglandin synthesis in both the peripheral and central nervous system. Note: Prostaglandins are involved in the inflammatory process as well as the production of pain. Examples in which NSAIDs, may help relieve pain are:

Inflammatory conditions such as rheumatoid arthritis

Mild to moderate pain associated with the back or headache

Conditions associated with excessive prostaglandin production at the site of injury or pain, (i.e., where certain malignant tumors exist, in cancer therapies, bone metastases,



postoperative pain)

Adjuvant analgesic in chronic and severe pain. Although NSAID’s have a similar mechanism of action, there are differences in their onset, duration of action, and their potency. Most NSAID’s also have a maximum dose or “ceiling”. Adverse effects associated with NSAID’s may occur when the maximum dose has been exceeded; therefore, clinicians must know the “ceiling” of the agent utilized. Adverse effects of NSAID’s include:

Gastrointestinal effects: Dyspepsia or Peptic ulcers

Fluid retention

Hepatic dysfunction and renal failure

Platelet inhibition

Patient response to the various NSAID’s also varies. If a patient with chronic pain does not respond to a particular NSAID at the the maximum therapeutic dose, an alternative must be considered. The Cyclooxygenase-2 (COX-2) selective NSAID’s provide the efficacy of the nonselective NSAID’s with significantly less risk of gastroduodenal ulceration and bleeding problems, and absence of platelet inhibition. (4), While these agent are useful, they must be used with cautions due to safety issues associated with their use, such as stroke, MI, blood clots, and other cardiovascular events. These adverse effects led to the withdrawal of two COX-2 selective inhibitors, rofecoxib (Vioxx®) in 2004 and (Bextra®) in 2005. The most commonly used COX-2 selective inhibitor for pain is celecoxib (Celebrex®). Although celecoxib is approved for use in patients with acute pain, osteoarthritis, rheumatoid arthritis, dysmenorrhea and ankylosing spondylitis its benefits must outweigh the risks. Its use is only recommended in patients at high risk of GI bleeding or ulceration or failure in alternate treatment options, and should be used at the lowest dose for the shortest duration possible.

3. Opioid Analgesics

Opioid analgesics are the standard for treatment of moderate to severe pain. The choice and dosage of an opioid depends on the severity of the pain, the setting, route of administration, patient preference, efficacy, pharmacokinetics, cost, and adverse effects of the drug. All opioids have similar actions but differ in terms of potency, duration of effect, availability and intrinsic efficacy. Morphine is the standard to which other opioids are compared for potency and effect. Opioids are available in

many dosage forms to meet patient needs. (i.e., oral, sublingual, rectal, parenteral, transdermal, intrathecal, epidural etc.).

Most strong agonists do not have a ceiling. They do however, present with

side effects due to their agonistic binding at the mu-receptor site. These effects include: sedation, nausea, vomiting, confusion, itching, constipation, and urinary urinary retention. With the exception of constipation, most of the side effects will diminish over time. Caution must be utilized in patients with bronchial asthma, impaired ventilation or increased intra-cranial pressure because theses patients may be at risk for further respiratory compromise. The respiratory depression associated with opioid use is usually short lived, occurs more often in opioid-naïve patients, and is antagonized by the patient’s pain.



Allergy to opioids does occur. If an allergy should occur, avoid the use of another opioid from the same chemical class.

Opioids are classified as full morphine like agonists, partial agonist, or mixed agonist-antagonists.

a. Full agonists

Morphine, hydromorphone, codeine, oxycodone, hydrocodone, methadone, levorphanol, and fentanyl are classified as full agonists because their effectiveness with increasing doses is not limited by a ceiling. They are the most frequent choice for the treatment of cancer pain.

Morphine has a short half-life and no toxic or active metabolites. It is generally well tolerated and the first line treatment for injectable analgesia. Morphine may be administered via oral, rectal, IV, SC, intrathecal, inhalation, or epidural route.

Hydromorphone (Dilaudid®) is a synthetic opioid that is an excellent alternative to morphine and is available in a variety of forms (tablets, liquids, suppositories and parenteral). Hydromorphone is useful when pain control is inadequate with morphine or when patients experience side effects or an allergy to morphine.

Codeine is available for mild to moderate pain, with limited use for severe pain. Codeine must be broken down in the liver to morphine to provide analgesia. Nausea and constipation occur more frequently with codeine than with the other opioids at equianalgesic doses.

Oxycodone oxycodone is available as a single entity in an immediate and controlled release form that may be used to treat moderate to severe pain. This synthetic opioid has better oral absorption when compared to morphine and is less likely to cause nausea and vomiting when compared to morphine.

Hydrocodone is a combination product with acetaminophen. These combination products have ceiling doses based on their potential to produce acetaminophen toxicity. (Max. 4 gm/24hr). Thus, dose escalation can limit their usefulness.

Methadone Methadone hydrochloride is similar in safety and efficacy to other narcotic analgesics when used in equal analgesic doses and exhibits actions that are similar to morphine once bound. Methadone exhibits incomplete cross-tolerance with other opiate agonists thus it is an excellent alternative in patients who are refractory to, or intolerant of, dosage increases or other opiate agonists. Methadone hydrochloride exhibits high interpatient variability as well as pharmacokinetic properties depending on the route of administration. It should be noted that with repeated doses, methadone’s duration of action may be prolonged and sedation may be a major problem. Traditionally, methadone has been used to suppress withdrawal symptoms in heroin addicts; however, it is being used fairly frequently by pain specialists.

Levorphanol is a potent synthetic mu-agonist opioid that exerts its action at receptors in the periventricular and periaqueductal gray matter in the brain and spinal cord, thus altering transmission and perception of pain. It produces morphine-like analgesia.

Fentanyl is 100-fold more potent than morphine with a short half-life and duration of action. It is commonly administered as a transdermal patch that takes 12-24 hours to reach peak effect and last 72 hours. Patients often have exhausted transdermal patch pain control prior to starting injectable therapy. Fentanyl is usually administered as a transdermal patch, IV, inhalation, or epidurally.



b. Partial agonists such as buprenorphine are less effective analgesics and there use in

moderate to severe pain is very limited. (2)

c. Mixed agonist-antagonists (i.e., pentazocine [Talwin®], butorphanol tartrate [Stadol®], denocine [Dalgan®], and nalbuphine [Nubain®]) are neutral at one type of opioid receptor while activating a different opioid receptor. These drugs are contraindicated for use in the patient receiving an opioid agonist because they may precipitate a withdrawal syndrome and increase pain. Their analgesic effect is limited by a dose-related ceiling effect on respiratory depression. (2) Their use in moderate to severe pain is very limited.

d. Meperidine is useful for short courses of pain management to treat acute pain. Meperidine

should be avoided in chronic pain or in patients with compromised renal function due to the accumulation of the toxic metabolite normeperidene.

e. Tramadol is an atypical opioid analgesic with dual action. It is a weak mu opioid agonist and also inhibits the reuptake of norepinephrine and serotonin. (2) The most common side effects are drowsiness, constipation, dizziness, nausea, and orthostatic hypotension. (2)

f. Pure opioid antagonists (i.e., naloxone [Narcan®] and naltrexone [Revia®]) bind competitively to opioid receptors, completely blocking them and producing no analgesic response. Naloxone is used only to reverse the life-threatening respiratory depression effects of opioids if an overdose occurs. (3)

g. Nerve Blocks

Injection of lidocaine, bupivacaine or ropivacaine, alone or with an anti- inflammatory for longer lasting effect can provide relief from nerve or root compression. Placement of a catheter at a sympathetic ganglion extends the block to days or weeks. Destructive agents such as ethanol or phenol can be used to destroy the nerve pathway and provide permanent pain relief.

4. Principles of oral opioid administration include: (1)

Administer analgesics around-the-clock (A-T-C) at a fixed schedule whenever possible to prevent pain (rather than waiting until it is severe).

Several products are available as extended release dosage forms. The controlled-release oral preparations allow administration usually twice-daily (occasionally every eight hours) once steady-state drug concentrations are achieved. They must not be broken, crushed or chewed.

Supplement with as-needed (rescue / breakthrough) doses of short-acting immediate release drugs (i.e., oxycodone, morphine, hydromorphone). Breakthrough doses are generally 10-20% of the total fixed dose.

Dose titration is determined by pain relief and the balance of analgesia with side effects. Strong opioid agonists have no maximum dose or ceiling dose. The rate of increase depends on the drug formulation. Immediate-release products can be increased daily. Increase of 25-50% of the previous dose can be done if pain is uncontrolled. At higher opioid doses increases of 20-30% would be more prudent.

Frequently reassess efficacy and side effects and adjust dose as needed.

If dose reduction or therapy interruption is needed for some rare reasons, taper down rather that abruptly discontinuing the medications.

5. Opioid switching

There is evidence that switching to an alternative opioid can many times result in improved pain management and decreased toxic effects.



The guidelines for opioid switching are intended to reduce the risk of relative overdosing or underdosing as one opioid is replaced by another. These guidelines require a working knowledge of an equianalgesic-dose table. [1] The equianalgesic-dose table provides only a broad guide for dose selection when switching from one opioid to another. An equianalgesic-dose table can be found in Micromedex or other current reference material. Wide ranges in interindividual responses to the various opioids have been noted. [1] Therefore, because of incomplete cross-tolerance in most cases, the calculated dose-equivalent of a new drug must be reduced by 25% to 50% to ensure safety. These figures are based on clinical experience rather than empiric data. The selection of an alternative opioid is largely empirical. There is little clinical evidence to indicate that one opioid has therapeutic superiority over another opioid. A patient, for example, who requires a switch from morphine to another opioid can be switched to hydromorphone, oxycodone, fentanyl, or methadone. [1] In one prospective study of 186 cancer patients being treated with morphine, 25% did not respond and required switching to another opioid (oxycodone). The primary reasons for switching included pain, confusion, drowsiness, nightmares, and nausea. Of the 47 patients who required switching to an alternative opioid, 37 (79%) obtained good relief. This result provides beginning evidence for the prevalence of the need to switch, as well as determining the success rate once switching occurs.[1] Patients should be followed closely after a switch and should be reassessed, and the new opioid dose should be adjusted according to the intensity of pain and lack or presence of adverse effects.

Refer to the Narcotic Analgesic Comparative Review Micromedex, DrugDex Consult (4) for further drug comparisons.

C. Routes and Modes of Administration

1. Oral Administration Oral administration of medication provides many advantages over the more complex, invasive regimens (i.e., intravenous, intraspinal, and subcutaneous). These include, but are not limited to the following:

A lower patient cost

Flexible and convenient dosing for the patient

Ease of administration

Availability of medications (i.e., agents are available in a variety of formulations: immediate-release tablets, capsules, elixirs, and solutions as well as controlled-release tablets and capsules).

When feasible, treatment with oral medications is the preferred route of administration; however, this method of drug delivery may be ineffective, impractical or contraindicated in a variety of conditions (i.e., dry mouth, difficulty swallowing, persistent nausea and vomiting, bowel obstruction, global weakness, malabsorption, coma, and the requirement to ingest a large number of tablets).

2. Intramuscular Administration

The intramuscular (IM) route may be used to treat postoperative pain, however, it is not recommended for chronic pain management mainly due to the pain on injection and need to be administered by a clinician.

3. Subcutaneous Administration Continuous subcutaneous infusion is a well-accepted means of

of administering parenteral opioids chronically in the home. Absorption is reliable, rapid, and consistent serum levels are obtained as when opioids are administered intravenously, but without the requirement for maintaining an intravenous line. Continuous administration is achieved with the use of a small volume infusion pump (e.g., CADD Prizm , Curlin, etc.) and when properly titrated, it minimizes peaks and valleys in plasma drug concentrations. The use of a pump also allows for the addition of patient controlled analgesia (PCA) where the patient and caregiver(s) can be instructed to access and manage their own infusion. Although most opioids



can be administered via the subcutaneous route, morphine or hydromorphone are the most commonly used agents. Patients with advanced illness are sometimes edematous (fluid filled) or cachectic (a muscle wasted state) and as a result, have absorption issues. In these patients intravenous administration may be preferred. The drug is usually put in a cassette or IV bag (50, 100, or 250ml) that can hold a 3-7 day supply. Note: The infusion rate of subcutaneous administration should usually not exceed a volume of 2 milliliters per hour. Therefore, a high concentration solution may be needed. Refer to nursing references if further details are needed.

4. Intravenous Administration

Intravenous route of administration is the route that provides the most rapid onset of analgesia. It is ideal when administering medications that are of short duration, or when the patient has ongoing pain that necessitates a steady level of analgesia. This is a brief summary of the basic things to consider when providing parenteral pain management in the alternate site setting. Refer to your organization Policies and Procedures for further details.

Administration method:

The medication type as well as product stability and compatibility must be taken into consideration when determining how to prepare the medication and the amount of medication to be dispensed. An ambulatory infusion pump with Patient Controlled Analgesea (PCA) features (e.g., CADD Prizm , Curlin, etc.) is generally required. This allows the patient to give boluses during a routine time period before the pain becomes severe.

PCA provides the patient/family member with the ability to administer a precise, pre-calculated bolus dose prior to movement or as a means to manage breakthrough pain. By allowing for prompt relief of the pain they may be more active, and may have enhanced feelings of autonomy and self control. Patients should have a PICC, central line, or implanted port for access to the venous system. Peripheral lines are not recommended due to the chance of line complications and subsequent abrupt therapy interruption. The drug is usually put in a cassette or IV bag (50, 100, or 250ml) that can hold a 3-7 day supply. It is best to have an extra bag available in the home in case one is damaged. Thus it is generally better to dispense two bags per delivery period rather than one 500 or 1000 ml bag. Consider having a back-up pump in the home if the patient lives a long distance from the pharmacy.

5. Intraspinal Administration

Epidural and Intrathecal opioid analgesia is an adaption of the administration of local anesthetic by these routes which has been used for surgery for over a hundred years. Administration by these routes began to develop following the discovery of spinal opioid receptors. When opioids are administered directly into the epidural or intrathecal space, they bind to specific opioid receptors. In contrast to the spinal administration of local anesthetics, spinal opioids produce highly selective analgesia without numbness, motor weakness, or the hypotension that follows sympathetic blockade. Intraspinal administration of opioids is effective in the management of severe postoperative, chronic or cancer pain in patients who experience unacceptable and persistent side effects to analgesics administered by other routes. Drugs may be administered by intermittent injection, continuous infusion via an external pump, or automatically through the use of a preprogrammed computerized internal/implanted pump (i.e., SynchroMed). Therapy is



usually preceded by trial infusion through a temporary epidural catheter or by trial “single shot” epidural or intrathecal injections. These trial doses assist in predicting whether spinal administration will be successful and free of side effects. Spinal analgesia tends to be more effective for pain below the mid-chest although it may be used in selected circumstances for pain in any site. Temporary catheters may be placed at the bedside or in an outpatient clinic, while the more sophisticated devices require minor surgery and, possibly a brief hospital admission to initiate therapy. Only preservative free medications and diluents are used intraspinally. Sodium chloride 0.9% is the recommended diluent. The most commonly used drugs are:

Morphine

Hydromorphone

Fentanyl

Bupivicaine

Ropivicaine

INTRATHECAL ONLY

Baclofen

Clonidine

Ziconotide (Prialt®)

These drugs are often utilized in various combinations to treat unresponsive intractable pain. Information is limited regarding these combinations but it is important for the clinician to be aware of this routine. Epidural analgesia produces a 5-10 fold more potent effect than when given intravenously and can usually be achieved with low doses, often as low as (1/10) the intravenous dose and titration is required; therefore, side effects via this method of drug delivery tend to be infrequent. Bupivicaine and ropivacaine are the most commonly used anesthetics in continuous epidural infusions. Morphine, fentanyl, and hydromorphone are also used and often added to the local anaesthetic infusions. Intrathecal analgesia is delivered via a catheter implanted into the subarachnoid space and attached to an implanted port or implanted pump that holds the medication (i.e. SynchroMed®). A needle is inserted through the skin into the port to fill the pump that holds approximately 20mls of the drug solution. The pump is usually filled once a month using a Medtronic Intrathecal refill kit or other preservative-free solution. Because drug is administered even closer to its receptors, the doses required to produce intrathecal opioid analgesia are only about 1/10 of those required for epidural administration, and may be as low as 1/100 of intravenous doses. Note: This dose relationship is approximate, and titration is required. The duration of effective analgesia following single doses of intraspinally administered opioids is considerably longer than systemic administration For example, the effects of a single dose of morphine usually last from 12 to 24 hours. Note: Refer to the pump manufacture references prior to filling the reservoir with any drugs or solutions. Some solutions can precipitate in the pump and cause permanent damage. Most pharmacies do not provide intrathecal combination products due to the need to compound these from non-sterile powders and the lack of concrete stability information. This compounding practice is also classified as High Risk and strict USP <797> standards must be followed. Detailed discussion of intrathecal medication administration is beyond the scope of this monograph. Further information can be found in your company’s internal resources or in the following articles.



Ghafoor V, et al. Intrathecal drug therapy for long-term pain management. Am J Health-Syst Pharm.2007:64:2447-61. Polyanalgesic Consensus Conferene 2007: Recommendations for the Management of Pain by Intrathecal (Intraspinal) Drug Delivery: Report of an Interdisciplinary Expert Panel. Neuromodulation: Technology at the Neural Interface. 2007;10:4. Polyanalgesic consensus conference 2003: An update on the management of pain by intraspinal drug delivery. J Pain Symptom Manage 2004;27:540-53

8. Miscellaneous a. Topical

Other methods of administration include the application of topical medications such as those containing capsaicin, a powerful irritant found in Zostrix®, topical local anesthetics such as lidocaine or benzocaine (available in a variety of forms: ointment, cream, patch, spray, jelly), or rubs and liniments that contain various amounts of menthol, camphor, and methyl salicylate (an anti-inflammatory agent) or a combination there of. Various topical products for minimizing discomfort caused by injections are also employed in pain management. Topical cream containing a eutectic mixture of lidocaine and prilocaine (EMLA® )in reducing pain associated with veni- puncture, lumbar puncture, arterial puncture, and port access. It may also be effective when applied to painful cutaneous lesions (i.e. post- herpetic neuralgic and painful ulcers). For optimal effect the product should be applied and the area of application covered with an occlusive dressing one hour prior to a procedure. Note: EMLA

penetrates the skin to a depth of 5mm.

b. Rectal The rectal route may be considered for selected patients who cannot tolerate or use oral medications or for whom first pass metabolism is an issue. The applicability of this route may be limited by the amount of drug required, rectal pathology or patient/caregiver acceptance. Clinicians must be aware that there is variability in rectal absorption of drugs and this variability may affect the dosage needed to provide analgesia. Rectal administration may be most useful on a temporary basis and its use must be avoided in patients who have diarrhea, a colostomy, anal fissures and hemorrhoids. Rectal suppositories are contraindicated in

neutropenic patients due to the risk of trauma and bleeding. c. Transmucosal: Sublingual and Buccal

Delivery of a pain medication sublingually (under the tongue), or via the buccal route (between cheek and gum) is particularly useful in patients who are unable to swallow and who need short term maintenance drug therapy (i.e. usually when death is imminent). Morphine elixir is often used sublingually. Disadvantages to this route of drug delivery include variable absorption, unpleasant taste, and limiting doses. Oral transmucosal fentanyl citrate (Actiq®) is a prescription opioid that is available as a lonzenge (on a stick) for the management of breakthrough cancer pain in patients who are already opioid tolerant. When placed between the cheeks and gums and slowly sucked for 15 minutes, the drug dissolves and



is absorbed through the mouth’s lining into the blood stream. Full relief may not be reached for up to 45 minutes post dose. Actiq® must not be chewed, nor should the patient consume anything while using the lozenge. Upon completion, Actiq® must be disposed of properly as this agent may be harmful or fatal to a child or other adults for whom this product has not been prescribed. (4) The most common side effects with Actiq® are sleepiness, nausea, or dizziness. Actiq® will also add to the effects of alcohol and other central nervous system depressants (i.e. antihistamines, tranquilizers, sedatives). Each lozenge contains about (½) teaspoon of sugar and may increase the risk of dental caries. Diabetics should inform their physician that they are taking Actiq®. Safety as well as the appropriate dosing of Actiq® in opioid tolerant children with breakthrough cancer pain has not been established below the age of 16 years.

d. Intranasal Intranasal administration involves the delivery of a calibrated, aerosolized dose of medication into the nasal passage where it is picked up and absorbed by the abundant blood supply in the nose. This route of drug delivery avoids first pass metabolism by the liver. Examples of drugs delivered intranasally for pain are butorphanol (Stadol®) and sumatriptin (Imitrex®). Disadvantages of intranasal therapy include local irritation as well as bleeding and runny nose.

e. Inhalation The inhalation method provides systemic administration of the drug, however, there is a

large variation in the amount of absorption. Opiods can be delivered by inhalation via a wet nebulization in a wide range of doses, concentrations, and volumes. The indications include: decrease breathlessness sensation in patients with chronic lung disease, dyspnea at rest associated with severe heart or lung disease, pain after surgery, and for general analgesia. The drugs are generally well tolerated but general side effects include: bitter tastes, cough, and nasal pruritis. Absorption is rapid however, there is very little evidence of local action on the lung. Drugs should be diluted in 3-5 mls of Sodium

Chloride 0.9% and administered every 4-6 hours as needed via nebulizer or similar device. Refer to your companies internal resource for common drugs and dosing guidelines

f. Transdermal (4))

Transdermal fentanyl (Duragesic®) patches are available for use in chronic pain management. Ordinarily a short acting drug when administered IV, the transdermal system converts fentanyl into a long acting agent. The drug is absorbed through the skin into the systemic circulation, providing analgesia of 72 hours duration with each application, once steady state has been achieved. Factors specific to administration include:

The patch must be applied to a non-irritated and non-irradiated area of skin on a flat surface such as chest, back, flank, or upper arm. Do not use soaps, oils, lotions, alcohol or other agents

to clean area, nor shave hair at site prior to application. Absorption of fentanyl is influenced by internal and external heat

Following initial application, there is a 8-12 hour delay before analgesia is established and effects may persist for an additional 8-12 hours after patch removal.

It takes greater than 17 hours for fentanyl serum concentration to fall by 50% after patch removal. If the system must be removed



(due to side effects), careful observation, and occasionally naloxone may be required for up to 12 hours following system removal.

The Duragesic® system is not recommended for rapid titration in patients with unstable angina due to its long latency to effect.

Serious or life threatening hypoventilation can occur with the patch; therefore therapy is contraindicated in patients receiving a dose in excess of 25mc/hr at the initiation of opioid therapy.

A small proportion of patients will require that their patches be changed every 48-60 hours.

To convert patients from opioid to the transdermal system follow the guidelines provided in Micromedex (4)

D. Adjuvants Medications

Drugs that are not pharmacologically classified as analgesics but are used alone or in combination with opioids to relieve pain are called adjuvant analgesics or co-analgesics. Adjuvant analgesics are used for specific purposes, such as neuropathic pain, anxiety, nausea and vomiting, etc. Adjuvants tend to work for specific conditions, and the dose-response relationship of these agents is not linear. A good example of this is the use of tricyclics and anticonvulsants. These agents may/may not be effective in a given patient, they may take a few days to a few weeks before they are effective, and they tend to work at low doses, with no assurance that analgesia will improve with dosage increases. The adjuvant drugs include the antidepressants, antihistamines, steroids, psy-stimulants (amphetamines), neuroleptics (anticonvulsants, relaxants), local anaesthetics, laxatives, and antiemetics.

1. Tricyclic Antidepressants (1)

Tricyclic antidepressants (TCAs) such as amitriptyline (Elavil®), desipramine (Norpramin®), maprotiline (Ludiomil®), duloxetine (Cymbalta®), nortriptyline (Pamelor®, Aventyl®) and venlafaxine (Effexor®) have an additive benefit to opiate analgesia. They also benefit patients suffering from a variety of diseases such as post-traumatic stress disorder, depression, insomnia, and anxiety. Their mechanism of action is thought to involve the blockade of:

Sodium channels

Serotonin and norepinephrine re-uptake at nerve synapses

N-methyl-D-asparatate receptors. While amitriptyline and desipramine have the best supporting efficacy evidence, while new agents are gaining support. It may take about 2-4 weeks before the analgesic effect is seen in some patients. Their dosing as well as side effect profiles may also vary thus limiting their use particularly in the geriatric population; therefore, the TCA with the lowest risk of adverse effects at the lowest effective therapeutic dose must be given to the patient on the simplest schedule. Even then, commonly reported adverse drug reactions such as constipation, dry mouth, blurred vision, cognitive changes, tachycardia, and urinary retention occur. A slow upward titration is suggested as a good way to avoid side effects.

Patients that present with a history of cardiac arrhythmias, Alzheimer’s disease, or falls should avoid the use of TCA’s.

2. Antihistamines (1) The antihistamine used most frequently is hydroxyzine (Vistaril®, Atarax®). Clinical studies show that 100 mg of hydroxyzine combined with 5 mg of



morphine may produce the same level of analgesia as 10 mg of morphine. Although they may be used for acute pain, they are not practical for the control of cancer pain; therefore they are seldom used. Hydroxyzine also has antiemetic and sedative properties.

3. Corticosteroids (1)

Corticosteroids are used in cancer related pain (i.e., epidural and spinal cord compression, intracranial pressure) and musculoskeletal conditions (i.e. arthritis, bursitis, tendonitis). Likewise they are effective for reducing pain associated with edema pressing on nervous tissue. Additional benefits associated with the use of these steroids includes stimulation of appetite and resultant weight gain, and improved mood. Corticosteroids are generally well tolerated with short-term treatments but adverse reactions and toxicities often evolve with long term, high dose treatment. Dexamethasone and methylprednisone are the main drugs of choice. Their mechanism of action involves inhibition of prostaglandin synthesis. Potential side effects with this therapy include drug induced adrenocortical insufficiency, masked signs of infection, electrolyte/body fluid imbalance, hypertension, psychiatric syndromes, and gastrointestinal issues (i.e., ulcers, bleeding). Steroids must be tapered slowly since abrupt withdrawal may exacerbate pain. NSAID’s must not be used concomitantly with steroid therapy as the combination of these agents will increase the incidence of gastrointestinal side effects.

4. Psychostimulants (1) Amphetamines (dextroamphetamine and methylphenidate) may potentiate the analgesic action of opioids and may decrease the sedative effects produced by opioid therapy. These agents are useful in managing cancer patients with concurrent depression or lethargy.

5. GABA-B Receptor Agonists (1) Baclofen (Lioresal®) is used for spasticity associated with neuropathic pain that is non-responsive to other treatments. It is usually given intraspinally. Baclofen infusions must be discontinued slowly over time

to avoid delirium and seizures which are a direct result of abrupt withdrawal. 6. Anti-Anxiety Agents (1)

Benzodiazepines (e.g., diazepam, lorazepam, alprazolam and midazolam) are useful adjuvants in patients with high anxiety levels, muscle tension and nerve compression.

7. NMDA Receptor Antagonists (1)

Ketamine is a general anaesthetic that is used (in low doses) in patients suffering neuropathic pain (due to cancer) and who are non-responsive to other treatments. In lower doses, the severe CNS side side effects (i.e. delirium, dysphoria, psychosis, and hallucinations) can be avoided. 8. Anticonvulsants (1)

Anticonvulsants are useful in treatment of pain of a neuropathic origin that is intermittent, electrical and shooting in character (seizure-like). These agents are thought to work by preventing or suppressing abnormal, spontaneous, or pathological neuronal firing which occurs from abnormal



to normal neurons. Their mechanism of action is thought to involve the following:

Blockade of the sodium channel conduction and slowing of recovery rate of voltage-gated sodium channels

Modulation of GABA receptors and increase level of GABA in the brain

Inhibition of glutamate, aspartate and acetylcholine release Anticonvulsants commonly used in the management of pain include: carbamazepine (Tegretol®), clonazepam (Klonopin®, gabapentin (Neurontin®), phenytoin (Dilantin®), and valproate acid (Depakote®). Anti-convulsants can be used alone or added to a patients pain regimen if TCA’s alone are inadequate to manage neuropathic pain.

E. Opioid Antagonists (1) Pure opioid antagonists have limited applications in the home care setting. With careful titration and monitoring, a desired analgesic effect can generally be achieved without the potential for overdose. If patients begin to experience excessive side effects, the rate of administration of the opioid can be decreased accordingly. In the event of a life-threatening opioid overdose, the administration of a pure opioid antagonist will rapidly reverse the effects induced by the opioid. Some of these effects include, but are not limited to, depression, hypotension, and

sedation. The only pure antagonists that may possibly be used in the alternate site setting is Naloxone (Narcan®).

IV. DRUG ADMINISTRATION A. Equianalgesic Dosing (3)

Equianalgesic dosing is a methodology for converting between opioids and route of administration. Morphine 10 mg is the generally accepted reference for which all other opioids are compared. Equianalgesic dosing is identified in standard comparison charts and is based on experience in acute, short-term use of these agents. Patients receiving chronic or high dose pain management will exhibit altered pharmacokinetics, decreasing the oral: parenteral ratio by as much as 4-fold. For example, an effective conversion from oral to parenteral therapy in a patient on chronic morphine therapy may require a ratio as low as 1.5:1, as compared to the standard 6:1 ratio. When changing to another opioid (due to a need for increased potency or specific drug intolerance), it is suggested that the conversion start with one-half the equianalgesic dose of the new agent, and then titrate to achieve the desired analgesic effect.

The IM conversion value should be used for intravenous and subcutaneous administration. The standard equianalgesic conversion charts do not address conversations to epidural or intrathecal use. In general, the initial epidural dose is about 1/10 (ten percent) of the intravenous dose; the intrathecal dose is about 1/100 (one percent) of the intravenous dose. The initial response to intraspinal analgesia will vary with the lipophilicity (affinity for lipid molecule) of the drug. Morphine is more hydrophilic, so it will have a delayed onset and prolonged action;



fentanyl is more lipophilic, so it will have a rapid onset and shorter duration. Conversions to epidural or intrathecal should be done in a controlled healthcare setting.

The following case illustrates equianalgesic dosing conversion from oral to continuous subcutaneous morphine. Equianalgesic Case Example: MA is a 67 YOM with terminal pancreatic cancer. His pain is poorly controlled (7 on a scale of 10) with MS Contin 60 mg, five times daily, and 280 mg of Roxanol solution daily, in divided prn doses for breakthrough pain. He has been on morphine for 2 months. He is generally unable to sleep throughout the night.

To convert MA to a PCA parenteral therapy on morphine: Calculate the total daily amount of oral morphine MA takes

300 mg as MS Contin® plus 280 mg as Roxanol® equals 580 mg

Convert the daily oral dose of morphine to the daily parenteral equivalent using an appropriate ratio for the patient's opioid use history.

Chronic administration - use an aggressive ratio (i.e. 3:1) 580 mg PO converts to 193 mg parenteral per 24 hours

Divide by 24 to obtain an hourly rate.

193 divided by 24 equals 8 mg per hour (rounded).

Determine an appropriate continuous rate, bolus dose, and lockout interval for the patient. To initiate parenteral therapy, start at one half the rate and titrate for the first 24-48 hours in 2 to 4 hour intervals. Allow a sufficient bolus dose and frequency within a range to achieve the desired plan level with minimal side effects.

Start MA on 4 mg/hour continuous with 1mg bolus capabilities every 15 minutes (total of 4 mg bolus/hour). Monitor response and bolus usage, and adjust accordingly.

After achieving desired pain level with average activity level, set the continuous rate for constant pain control, and allow bolus doses for breakthrough pain due to activity, such as repositioning or moving.

After 36 hours, MA reports a pain level of 4 (out of 10). He is satisfied with the pain control, using an average of 6 mg per hour, including all boluses. The continuous rate is reset to deliver 6 mg per hour, with 1 mg bolus every 30 minutes. After an additional 48 hours, MA is able to maintain a pain level of 3 to 4 with boluses before climbing the stairs, taking out the garbage and bathing. He sleeps through the night.

B. Titrating Opioids

Analgesia should be considered ineffective if the patient rates his pain level near to or above his specified pain tolerance level. A general rule of thumb

is a pain level of 5 or less on a scale of zero to ten should not warrant dose changes. This is extremely patient specific and a tolerable pain level should be discussed with each patient and the clinician should document this. The dosage should be titrated upward until satisfactory analgesia is reached. The dose can be safely increased in increments of 10-20% of current dose, or by increasing the basal rate by 50% of the total daily bolus requirement for PCA patients to decrease bolus usage. Although there are no ceiling doses or upper limits for opioids, presence and severity of adverse effects and the route of administration need to be considered. If adverse effects make it difficult to increase the opioid dose one or more of the following



measures must be considered:

Aggressive treatment of adverse effects

Trial of a different opioid

Co-administration of nonopioid or adjuvant analgesic

Administration of epidural or intrathecal infusion C. Management of Adverse Effects (1)

1. Constipation (1)

Constipation is the most common side effect of opioid administration and is caused by the binding of opioids to receptor sites in the wall of the gastrointestinal tract, resulting in decreased motility. Constipation in the cancer patient can also be secondary to tumor involvement (bowel obstruction, ascites), cancer therapy (vinca alkaloids, radiation), poor fluid intake, inadequate diet and lack of exercise further complicate the problem.

Tolerance to constipation does not occur over time; therefore, constipation must be anticipated and an aggressive preventative approach must be adopted to avoid problems. It is a good idea to ask the patient/caregiver about the patients usual bowel habits and chosen method to control irregularity. If none are employed, the patient on around-the-clock opioids must be placed on a stool softener with a a mild stimulant laxative. (i.e., docusate/senna). Important points to remember in managing opioid induced constipation:

Select a reasonable goal: A bowel movement every 2-3 days (unless the patient is not taking anything orally.

Encourage fluid intake, exercise, and high fiber foods.

Frequent small liquid stools or fecal incontinence (spurious diarrhea) may indicate fecal impaction

If the stool softener/laxative is ineffective, and the patient is not impacted , Then an additional agent (i.e., mineral oil, magnesium citrated or an enema) may be employed.

Avoid bulk laxatives (i.e., Metamucil®, Citrucil®, Perdiem®). Patients rarely drink enough fluid to facilitation the action of bulk forming agents.

2. Nausea and Vomiting (1) The causes of nausea and vomiting are multi-factorial, and when present all potential causes must be investigated. One third or more patients will experience transient nausea and vomiting on their initial exposure to opioid therapy, or with dose increases. Tolerance develops over time in most patients, and as a result, every effort must be made to maintain opioid therapy until symptoms subside. The initial therapeutic approach involves patient education, reassurance and short-term antiemetic therapy. In most patients, side effects occur not only with morphine but can also occur with its derivatives and other narcotic analgesics. Important points to remember when managing nausea and vomiting:

Nausea if initiated, usually subsides after 48-72 hours.

Nausea is due to stimulation of the chemorecpetor trigger zone, administer prochlorperazine, hydroxyzine or ondansetron. If nausea persists, alternative agents that work by different mechanisms may be substituted or added to the regimen. Note: Scopolamine, which works at the vestibular center, may be helpful if nausea is worse with ambulation.

If nausea is due to slowed motility of the gastrointestinal tract,



metoclopramide, a properistaltic agent may used.

For chronic nausea, metoclopropamide, dronabinol, or the 5HT3 receptor anagonists (i.e., ondansetron, granisetron, dolastetron) as well as corticosteroids or other antiemetics may be used. These drugs must be tapered once symptoms subside.

If nausea/vomiting (n/v) persists, or if (n/v) is not controlled with antiemetics, consider a trial of a different opioid.

Note: Additional causes of nausea/vomiting may include: hypercalcemia, increased amount of sputum, other medications, or unrelieved pain itself.

3. Sedation (1)

Sedation and related phenomena (lethargy, fatigue, confusion, delirium, hallucinations) is not unusual during the first 24-72 hours after the initiation (especially the elderly) of opioid therapy. Potential causes include metabolic disturbances, malnutrition, sleep deprivation, organ dysfunction, medications, brain metastases, etc. These symptoms, like nausea and vomiting, usually resolve after a few days. Initial management employs patient education and reassurance.

Important points to remember in managing opioid-induced sedation include:

Sleep deprivation resulting from unrelieved pain may be the only reason for sedation.

If respiratory function is stable, the person is easily aroused, continue present regimen.

Sedation may occur when a regimen is initiated or when there is a a significant increase in dosage. This should decrease in 1-3 days. If not, it may be necessary to decrease the dose by 10-25% (if pain control can be maintained), substitute an alternate opioid, or add or increase the non-opioid for additional pain relief.

Additional factors such as organ pathology, other medications, or psychological causes may precipitate sedation. Eliminate non- essential CNS drugs.

Note: Sedation can occur without pain relief. Do not doubt the patient who is barely able to stay awake but still rates his pain at 8-10 on a scale of 1-10. Under this circumstance, switching opioids and/or adding adjuvant drugs (amphetamines) may be necessary. Treatment with daytime doses of the psychostimulants (i.e., methylphenidate, dextroamphetamine) often reverses persistent sedation.

4. Respiratory Depression (1)

Opioids cause dose-dependent respiratory depression due to their effects on brainstem respiratory centers. This adverse effect is lessened in patients that are opioid tolerant. Caution must be exercised when these agents are administered to patients with a history of respiratory disease. Since opioids lessen the work of breathing, they are also sometimes prescribed to control dyspnea. Although the agonist-antagonist opioids (pentazocine, butorphanol, nalbuphine) are not recommended for the management of chronic cancer pain, it should be noted that, while these drugs also produce dose dependent respiratory depression in low dose ranges, increases in respiratory depression level off as doses increase.

Important points to remember when managing respiratory depression:

Monitor respiratory status following large initial doses, even in tolerant patients.



Slowly titrate up dosages and be cautious when converting from one route of administration to another.

Monitor respiratory status in the elderly, debilitated patients, in patients on concurrent respiratory depressant drugs (i.e. benzodiazepine, tranquilizers) and patients that have a past medical history for pulmonary disease or sleep apnea

In severe respiratory depression, stop opioid until respiratory depression resolves and reinitiate at 75% of previous dose.

Use spirometry and oxygen on an as needed basis.

Physician orders for a narcotic antagonist (naloxone) should be reserved to reverse severe narcotic effects.

5. Itching (1)

The mechanism behind the itching associated with the administration of opioids is not fully known. It is thought to be related to the release of histamine from mast cells or the disinhibition of itch specific neurons. If the itch is accompanied by a rash, allergy cannot be ruled out. The general approach to the treatment of pruritis (itch) includes: diphenhydramine (Benadryl®), hydroxyzine (Atarax®),cyproheptadine

(Periactin®), naloxone (Narcan®) or nalbuphine (Nubain®).

6. Urinary Retention (1) Urinary retention may occur with any opioid administered by any route, but is infrequent except in males receiving intraspinal opioids. Morphine increases smooth muscle tone in the urinary tract and inhibits bladder motility and the voiding reflex. Bladder catheterization and stimulants may be required while awaiting the development of tolerance.

V. PAIN MANAGEMENT IN THE PEDIATRIC AND GERIATRIC POPULATION

A. Considerations in treating Pain in Children

Assessment techniques used in children need to be simple to use. The Wong Baker FACES scale is a common tool that allows the child to describe their pain based on facial expressions. (Appendix A)

Assessing pain in children employs the following concepts:

Before assessment: Find out child’s word(s) for pain. Have child give examples.

Discuss pain with the child, family and other caregivers. Include history of previous pain experiences, types of pain and child’s reaction to pain.

Identify pathology or procedures known to cause pain

Observe behavior (i.e., vocalization, facial expressions, body movements, autonomic responses, changes in daily activity or usual behavior.

In choosing the starting dose of an opioid analgesic for children with postoperative or cancer pain, the age, weight and prior opioid experience of the child must be considered. Refer to common reference source for opioid and non-opioid analgesics safe to use in pediatrics. As a general guideline, it is usually recommended that:

children 12 years of age or older receive full adult doses

children 7-12 years of age generally require 50% of the starting adult dose

children 2-6 years of age require 20-25% of the starting adult dose

Recommended Tools for Assessing Children’s Pain



Assessment tool Recommended age

Description

Wong-Baker FACES Scale 3-17 years From a series of faces that show increasing levels of distress, children select the face that most closely resembles their pain level.

FLACC Pain Scale 1-3 years A behavior and pain assessment scale for use in patients unable to perform verbal responses, such as pediatrics or cognitively impaired patients. Based on 5 categories: Face, Legs, Activity, Crying, and Consolability.

B. Considerations treating pain in Geriatric Patients over 65 years old Age related physiological changes and functional decline occur in most of the major organ systems in the geriatric patient thus affecting the absorption, distribution, metabolism and excretion of drugs.

Many geriatric patients take between 8 and 12 medications a day; therefore, they often present with complex medication regimens that put them at increased risk for drug-drug and drug-disease interactions.

Elderly patients may be at risk for under treatment of pain because of a global under-

underestimation in their sensitivity to pain. This in part is due to a variety of factors both physical (i.e., neuropathy, poor blood circulation, decline in sensory input [sight, hearing] and mental disease such as Alzheimer’s) and psychosocial (i.e., limited ability to communicate and follow instruction as a result of educational, cost and income barriers).

Observation of non-verbal behavior are extremely important in assessing patients with such difficulties. Pain scales must be used with sensitivity to the patient’s disabilities. For example, large print may be helpful when a patient has a vision impairment. Also additional time may be necessary to allow the impaired elderly patient to understand and respond to questions. The elderly relate best to pain-measuring scales that include the 0-10 scale or the happy to sad Wong-Baker FACES scale used for children. In the comatose patient, agitation, restlessness, pupil dilatation and sweating may be clues to increased pain.

Nonsteroidal anti-inflamatory drugs (NSAIDs) are more likely to cause gastric and renal toxicity and other side effects in older patients. Opioid management in the geriatric population differs from that of the general population. Opioids have a prolonged action due to their reduced renal clearance and altered pharmacokinetics associated with the aging process. This results in slower opioid clearance and increased sensitivity to the undesirable drug effects of the opioid. These effects include, but are not limited to sedation, urinary retention and respiratory depression. In general, analgesics may be given safely to geriatric patients; however the dose(s) usually need adjustment. The overall rules for drug therapy in the elderly are: start low, go slow but go. It is usually prudent to initiate therapy in lower than normal dose range (25-50% reduction), and titrate upward slowly (with 25% increases). Geriatric patients experience higher peak effects and longer duration of action.

Opioids to avoid in the elderly include those with long half-lives such as methadone hydrochloride because of accumulation, pentazocine (Talwin) because pulmonary artery constriction, delirium, and agitation occur more frequently in the elderly and Darvon (propoxyphene) and Demerol (meperidine) due to metabolite accumulation causing delirium and seizures.

VII. APPENDIX A



PEDIATRIC PAIN RATING SCALES

1. Wong/Baker Faces Rating Scale

A. Explain to the child that each face is for a person who feels happy because he has no pain (hurt, or whatever word the child uses) or feels sad because he has some or a lot of pain.

B. Point to the appropriate face and state, "This face is . . .":

0 "very happy because he doesn't hurt at all." 1 "hurts just a little bit." 2 "hurts a little more." 3 "hurts even more." 4 "hurts a whole lot." 5 "hurts as much as you can imagine, although you don't have to be

crying to feel this bad." C. Ask the child to choose the face that best describes how he feels. Be specific about

which pain (e.g., "shot" or incision) and what time (e.g., now?, earlier before lunch?). From Wong, D, and Whaley, L: Clinical Handbook of Pediatric Nursing, ed. 2, p. 373, St. Louis, 1986, The C.V. Mosby Company. Printed with permission of the publisher and authors who also give their permission for this to be duplicated and used in the care of children with pain. Can be duplicated for use in clinical practice.

http://www.med.umich.edu/pain/apainmgt.html




2. FLACC Pain Scale

The five categories are scored from 0-2 with a total score ranging from 0-10.

Categories

Scoring

0 1 2

Face

No particular expression or smile, eye contact and interest in surroundings

Occasional grimace or frown, withdrawn,

disinterested, worried look to face, eyebrows lowered, eyes partially closed, cheeks raised,

mouth pursed,

Frequent to constant frown, clinched jaw, quivering chin, deep furrows on forehead, eyes closed, mouth

open, deep lines around nose/lips

Legs

Normal position or relaxed

Uneasy, restless, tense, increased tone, rigidity, intermittent flexion or

extension of limbs

Kicking or legs drawn up, exaggerated flexion or

extension of limbs, tremors

Activity

Lying quietly, normal position, moves freely

and easily

Squirming, shifting back and forth, tense, hesitant

to move, guarding, pressure on body part

Arched, rigid, or jerking fixed position, rocking,

side to side head movement, rubbing of

body part

Crying

No cry/moan (awake or asleep)

Moans or whimpers, occasional cries, sighs,

complaint

Crying steadily, screams, sobs, moans, grunts, frequent complaints

Consolability

Calm, content, relaxed, does not require

consoling

Reassured by occasional touching hugging, or

‘talking to’, Distractible.

Difficult to console or comfort

Adapted from www.childcancerpain.org http://www.med.umich.edu/pain/apainmgt.html




VII. APPENDIX B Internet-Based Sources of Pain Management Information

Source and intended Audience URL

American Pain Society – Healthcare Professionals

www.ampainsoc.org/

Inflexxion, Inc. – Healthcare Professionals www.painedu.org/

American Academy of Pain Medicine – Healthcare Professionals and Patient

www.painmed.org/

Pain.com – Healthcare Professionals and Patient

www.pain.com

National Cancer Institute - Healthcare Professionals and Patient

www.cancer.gov

American Pain Foundation - Patient www.painfoundation.org/

M.D. Anderson Cancer Center - Patient www.mdanderson.org/topics/paincontrol

http://www.ampainsoc.org/

http://www.painedu.org/

http://www.painmed.org/

http://www.pain.com/

http://www.painfoundation.org/

http://www.mdanderson.org/topics/paincontrol



VIII. BIBLIOGRAPHY

1. Pain PDQ (Physicians Data Query) Health Professional Version, National Cancer Institute, Feb.2009.

2. Mershey H, Bogduk N: Classification of Chronic Pain, Second Edition. Part III: Pain Terms A Current List with Definitions and Notes on Usage”. International Association for the Study of Pain, Task Force on Taxonomy. IASP Press, Seattle 1994: pp 209-214.

3. National Comprehensive Cancer Network: NCCN Clinical Practice Guidelines in Oncology Adult

Cancer Pain v1.2009. Available at http://www.nccn.org/patients/patient_gls/_english/_pain/contents.asp. Accessed May 2009

4. MicroMedex, Accessed May 2009

5. Chou, R et.al. Clinical Guidelines for the Use of Chronic Opioid Therapy in Chronic Noncancer Pain,

The Journal of Pain Vol 10,No 2 (February), 2009:pp 113-130

6. McCaffery M, Pasero C: Pain Clinical Manual, Jan. 1999, Mosby.

7. Principles of Analgesic Use in the Treatment of Acute Pain and Cancer Pain, Fifth Edition, American Pain Society, 2003.

8. American Pain Society website: http://www.ampainsoc.org/, Accessed May 2009.

9. National Cancer Institute website: http://www.cancer.gov/, Accessed May 2009

10. World Health Organization: http://www.who.int/about/en/, Access May 2009

http://www.nccn.org/patients/patient_gls/_english/_pain/contents.asp

http://www.ampainsoc.org/

http://www.cancer.gov/

http://www.who.int/about/en/

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