FDA hormone replacement therapy Web site 6

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1 TABLE OF CONTENTS Caring for pain at UIMCC 1-5 FDA hormone replacement therapy Web site 6 P&T Committee Formulary Action - September Caring for pain at UIMCC The International Association for the Study of Pain defines pain as an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. Pain is recognized as a significant cause of morbidity in hospitalized patients, and consequently the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) has developed standards to ensure that healthcare practitioners are aware of and actively managing this issue. It is believed that the most common reason for unrelieved pain in US hospitals is the failure of the staff to routinely assess patients for presence of pain and pain relief. The University of Illinois Medical Center at Chicago (UIMCC) Pain Task Force has been working to improve pain management for patients at the Medical Center. The Task Force has developed clinical care guidelines which can be found on the UIMCC intranet under Clinical Care Guidelines. A pocket card summarizing these guidelines has recently been approved by the P&T committee and will be distributed to staff shortly. The purpose of this edition of the RxPress is to review common issues in pain management with an emphasis on drug therapy. The reader is referred to and encouraged to follow the UIMCC pain assessment and management guidelines when caring for patients. Background Although UIMCC adopts the International Association for the Study of Pain s definition of pain, the Medical Center also recognizes the patient s self-report of pain as an acceptable definition due to the subjective nature of pain. Pain is generally classified as nociceptive or neuropathic. Each of these types of pain occurs through different mechanisms, and they are treated differently. Nociceptive pain encompasses visceral (internal organs) and somatic (skin, bone, joint, muscle, or connective tissue) pain and is caused by injury to the body. The mechanism by which nociceptive pain is transmitted begins with stimulation by noxious stimuli. Noxious stimuli activate nociceptors (free nerve endings) and cause the release of a variety of substances such as prostaglandins, histamine, and substance P. Patients perceive pain when the impulse is transmitted via the spinal cord. Common patient descriptors of nociceptive pain include: Somatic pain pin prick, stabbing/throbbing, and sharp. Visceral pain ache, pressure, or sharp. On the other hand, neuropathic pain results from a disturbance (disease/injury) or abnormal processing in nerve function. Unlike nociceptive pain, there usually is no connection between any injury to the body and the discomfort that is experienced. Common types of neuropathic pain are diabetic neuropathy, trigeminal neuralgia, HIV-associated pain, and post-herpetic neuralgia. Common patient descriptors of neuropathic pain include: burning, tingling, pricking, electric-shock like, or shooting. Assessment Pain is an extremely subjective experience; therefore, assessment of pain must be based on the patient s 1

2 perception/description. Simple methods have been successfully used in hospitals to determine information about the patient and pain control. These methods include the verbal rating scales (VRSs), numerical rating scales (NRSs), visual analog scales (VASs), and the Wong-Baker FACES Pain Rating Scale. Verbal rating scales typically verbal pain descriptions are ordered from least to most intense; patients verbally describe the severity of the pain they are experiencing. Ongoing assessment of pain is essential for proper management and as a follow-up to evaluate treatment. Pain must be assessed before and after each intervention. In the case of a pharmacological intervention, the timing of assessment will depend on the route of administration and onset of action of the agent. In general, it is appropriate to reassess pain 1 hour after a parenteral medication or 2 hours after an oral medication is given. Management of pain Treatment of pain is individualized based on the type and severity. The World Health Organization developed an analgesic ladder which addresses pain management at different intensities (see below adaptation). Numerical pain scales have the patient rate their pain intensity on a scale of 0 (no pain)-10 (worst pain). Patients report a number that best describes the severity of their pain. UIMCC Stepwise approach for caring for pain Step Pain Therapy Examples 1 Mild (1-4 on NRS of 0-10) non-opioid +/- adjuvant acetaminophen or ibuprofen 2 Mild to Moder- non-opioid +/- acetaminophen ate (5-7 on NRS of 0-10) 3 Moderate to Severe (8-10 on NRS of weak opioid +/- adjuvant Strong opioid +/- non-opioid +/- adjuvant + hydrocodone or codeine morphine or fentanyl Visual analog rating scale- the most common VAS consists of a 10-cm horizontal line or vertical line with 2 endpoints: no pain and worst pain ever. Patients are required to place a mark on the 10-cm line at a point that corresponds to the level of pain intensity they feel. Wong-Baker FACE pain rating scale - the patient is told to select the face that most appropriately describes his or her pain. This is a good scale to use when language barriers are present. 0-10) It is very important to remember that it is difficult to control pain once a patient is experiencing severe pain. Optimal treatment is often accomplished by aroundthe-clock administration of analgesics instead of using PRN or as needed scheduling when pain is intense or constant (e.g. present for most of the day). The as needed scheduling can be employed in conjunction with around-the-clock administration schedules to ensure that the patient is receiving optimal care for his/her pain. 2

3 Pharmacologic Therapies Non-opioids Acetaminophen, non steroidal anti-inflammatory agents (NSAIDs) and salicylates are commonly prescribed pain medications. The table below provides a summary of select non-opioid analgesics: Non-opioids Drug Usual adult dose Select side effects Contraindications Acetaminophen (APAP) 500 to 1000 mg po q 4-6 hours (Max of 4 g/day) Hepatotoxicity is the most concerning event otherwise acetaminophen is generally well tolerated Dosage reduction is necessary in patients with hepatic or renal dysfunction or those who drink alcohol excessively Ibuprofen 200 to 600 mg po q 4 to 6 hours (higher-end doses are used for inflammation; lower-end doses are used for analgesia) GI (upset, bleeding), renal, hepatic, prolonged bleeding time, dizziness, HA, fatigue, fluid retention -NSAID hypersensitivity -aspirin induced asthma Ketorolac 30 mg IV/IM q 6 hours (do not give intrathecally or epidurally) GI (upset, bleeding), renal, hepatic, prolonged bleeding time, dizziness, HA, fatigue, fluid retention -renal dysfunction -patients with suspected or confirmed bleeding OR those at high risk for bleeding -use during labor and delivery (potential effect on fetal circulation/uterine contractions) -do not exceed 3 days of therapy (UIMCC policy) Rofecoxib (Note: use restricted to patients at high risk for GI bleed) 12.5 to 50 mg po daily GI (upset, bleeding), renal, hepatic, prolonged bleeding time, dizziness, HA, fatigue, fluid retention -NSAID hypersensitivity -aspirin induced asthma Opioids Opioids are used in the management of moderate to severe pain or when the patient s pain cannot be controlled by non-opioids. Opioids work by blocking the release of substance P by interacting with one or more subclasses of opioid receptors, which prevents the pain impulse from crossing the synapse. According to the American Pain Society, morphine is the opioid of first choice. However, the selection of an alternative opioid is largely empiric. Keep in mind that there is little clinical evidence to indicate that any one opioid has therapeutic superiority over another. The table below provides dosing and equianalgesic doses for select opioids. 3

4 Short-acting opioids* Drug Equianalgesic dose IM/IV Equianalgesic dose oral Usual starting dose Adults** (IV or SC) Usual oral starting dose Adults** Morphine 10 mg 30 mg 2-5 mg q 3-4 hrs mg q 3-4 hrs Hydromorphone 1.5 mg 7.5 mg mg q 4-6 hrs 2-4 mg q 3-4 hrs Fentanyl 100 mcg N/A 50 mg IV q 1-2 hrs N/A Codeine 120 mg (IM only) 200 mg 15 mg q 4-5 hrs 30 mg q 4-6 hrs Hydrocodone N/A 30 mg N/A 5 mg q 4 hrs Oxycodone (nonformulary) N/A mg N/A 5 mg q 4 hrs *Adapted from the American Pain Society Guidelines, **for opioid naïve patients; dosage adjustments may be needed for the elderly or patients with hepatic/renal impairment. Of note, oxycodone and hydrocodone are available as combination products with acetaminophen. Hydrocodone is also available in combination with ibuprofen. Although there is no maximum dose of opioids, the doses of these combination products are limited by the non-opioid component. Switching opioids Equianalgesic doses are used to convert patients from 1 opioid to another. Conversions are performed for a variety of clinical situations including: patient response to a given analgesic, duration of action, desired dosage form, intolerable side effects, or the need to change the route of administration. These conversions should only be used as a guide and doses should be titrated based on patient specific characteristics including the severity of pain. It is sometimes advisable to start with a slightly lower dose of the new opioid (1/2 to 1/3 of calculated equianalgesic dose) to account for potential opioid cross-tolerance. To execute these calculations one should follow the following steps: (1) Calculate the total dose of the old opioid in a 24 hour period and put into the following equation: Current dose of old opiate (per 24 h) = Equianalgesic dose old opiate X (total daily dose of new opiate) Equianalagesic dose new opiate (2) Remember that you get the total daily (24 hour) dose of the new opiate when solving for X; therefore, divide the 24 hour dose of the new opioid to obtain the desired dose according to interval dose (such as dividing by two for a drug dosed every 12 hours or dividing by 4 for a drug dosed every 6 hours) Adverse Events Patients should be monitored for adverse effects such as mood changes, sedation, respiratory depression, nausea, vomiting, decreased gastrointestinal motility, dependence, and tolerance that commonly occur with opioid therapy. Sedation, constipation, nausea, vomiting, and itching are the most common side effects of opioids; dizziness, confusion, dry mouth, sweating, edema, and urinary retention are other side effects that may occur. Due to the risk for respiratory depression, extreme caution is advised when using opioids in patients with impaired ventilation, bronchial asthma, liver failure, and increased intracranial pressure. In fact, in patients with sleep apnea, airway obstruction can occur even when the dose and level of sedation are minimal. 4

5 Prevention and Management of Opioid Side Effects Adverse Effect Prevention and Management Constipation All patients on regularly scheduled opioids should be taking a mild stimulant laxative (e.g. senna, bisacodyl) ± stool softener (e.g. docusate). If no BM in 48 hours, give 30 ml sorbitol. Assess for fecal impaction if no BM in 72 hours. Nausea/Vomiting Add antiemetic - prochlorperazine, promethazine, or metoclopramide. Decrease opioid dose/increase dosing frequency; add or increase non-opioid analgesic for opioid-sparing effect. Change opioid if nausea persists. Pruritus (itching) Diphenhydramine mg PO/IV For opioids administered via PCA, consider low dose nalbuphine (2.5-5 mg) or naloxone (20 mcg) IV. Decrease opioid dose/increase dosing frequency; add or increase non-opioid analgesic for opioid-sparing effect. Consider changing opioids. Sedation Respiratory Depression Monitoring the patient s sedation level is the most effective way to prevent opioid-induced respiratory depression. Decrease opioid dose/increase dosing frequency; add or increase non-opioid analgesic for opioid-sparing effect. Consider changing opioids. Regular monitoring of sedation and respiratory status. Stop opioid and administer naloxone if patient is minimally responsive or unresponsive. Titrate naloxone carefully to avoid profound withdrawal, seizures, and severe pain. An initial naloxone dose of 0.4 mg per 10 ml of normal saline given as 0.5 ml by IV push every 2-3 minutes. From the UIMCC Pain management pocket card. Adjuvants In addition to opioids and NSAIDs, a number of other medications are used as adjuncts in the treatment of various pain disorders. These agents may or may not be indicated for pain. Examples of such drug classes are: Beta-blockers - commonly used medications for migraine prophylaxis, Anticonvulsants commonly used to treat neuropathic pain, and Tricyclic antidepressants - treatment of neuropathic pain/prophylaxis of migraine headaches. Conclusion The goal of postoperative pain is to provide effective, continuous, and safe pain relief to patients. Measuring pain levels by using standardized tools and reassessing continuously throughout the day is essential to treatment of postoperative pain. Using a multimodal therapy (e.g. NSAIDs and local anesthetics, in addition to opioids, for moderate to severe postoperative pain) to manage pain provides relief while minimizing the dose of opioids required. Selection of analgesia is patient specific due to the unique characteristics of nonopioids and opioids; patients often tolerate agents differently. Finally, monitoring, prevention, and treatment of adverse effects are crucial to prevent serious complications and are essential for patient comfort and satisfaction. Important phone numbers Pain service (call for PCAs, epidurals, special cases) (312) phone / (312) pager Pain clinic nurse (312)

6 Hormone replacement therapy Web site The Food and Drug Administration (FDA) has developed a consumer-friendly Web site on hormone replacement therapy (HRT) in response to recently published Women s Health Initiative literature regarding the adverse effects of this therapy. The Web site is available at http: // and contains facts about HRT including potential risks and benefits and questions for the woman to discuss with her health care provider. P&T Committee Formulary Action September 2003 Changes in Restrictions Nicardipine (IV) Restricted to Neurosurgery for treatment of hypertension associated with neurosurgical procedures and Cardiothoracic Surgery for postoperative hypertension associated with CABG Authors: Karen King, PharmD Amy Lodolce, PharmD, BCPS Michelle Gosa, PharmD candidate Abrar Baig, PharmD candidate Reviewer: Editors: Julie Golembiewski, PharmD Amy Lodolce, PharmD, BCPS Maria Tanzi, PharmD