Physiological and psychological experience for patients Can be seen as body s defense mechanism physiologically

Transcription

1 Pain Physiological and psychological experience for patients Can be seen as body s defense mechanism physiologically Avoid damaging situation Seek help Psychological factors can increase or decrease perception of pain E.g., anxiety vs positive attitude and support

2 Pain Assessment Subjective experience for patients Numerical scales and surveys assist in assessment Effective pharmacotherapy depends on Assessment of degree of pain Determining underlying disorders

3 Acute Pain Intense Defined period of time

4 Chronic Pain Lasts longer than six months Interferes with daily activities

5 Nociceptive Pain Due to injury to tissues Somatic: Sharp, localized sensation Visceral: Dull, throbbing, aching pain

6 Figure 18.3 Mechanisms of pain transmission at the nociceptor level

7 Neuropathic Pain Due to injury to nerves Burning, shooting, numbing More difficult to manage

8 Neuropathic Pain - Examples Carpal tunnel syndrome Degenerative disk disease Diabetic retinopathy Intractable cancer pain Phantom limb pain Postsurgical pain Sciatica

9 Treatment for Intractable Cancer Pain Radiation or chemotherapy Relieving nerve stimulation Surgery Nerve block

10 Pain Transmission Nociceptor stimulation Spinal cord receives pain impulse through A fibers (myelin) believed to signal sharp, well-defined pain C fibers (unmyelinated) believed to conduct dull, poorly localized pain

11 Substance P Neurotransmitter Passes on pain message from spinalchord to brain Affected by other neurons

12 Endogenous Opioids Group of neurostransmitters May modify sensory information, interrupting pain transmission Endorphins, dynorphins, enkephalins

13 Interruption of Pain Transmission Several target areas Peripheral level NSAIDs CNS level Opioids

14 Neural pathways for pain

15 Analgesics: Medications used to relieve pain. Opioids Non-opioids

16 Opioids Natural or synthetic morphine-like substances responsible for reducing moderate to severe pain Obtained naturally from opium (10% morphine, 2% codeine). Synthetic Meperidine

17 Opioid Receptors Receptors: mu, kappa, delta, nociceptin/orphanin FQ peptide For pain management, mu and kappa receptors are most important Opioid agonist drugs: stimulate mu and kappa receptors Opioid antagonist drugs: block mu and kappa receptors

18 Opioid antagonists Agents that displace opioid molecules from their neuroreceptors, and block opioids activating those receptors. Used effectively to quickly reverse toxic effects of opioid overmedication or overdose. The unexpected, paradoxical effects of opioid antagonists as adjuvants for enhancing rather than attenuating analgesic effects of opioids like morphine, oxycodone, and others.

19 Responses Produced by Activation of Specific Opioid Receptors Table 18.2 Responses Produced by Activation of Specific Opioid Receptors Response Mu Receptor Kappa Receptor Analgesia Decreased GI motility Euphoria Miosis Physical dependence Respiratory depression Sedation

20 Opioid receptors

21 Table 18.3 Opioids for Pain Management (1 of 3) Table 18.3 Opioids for Pain Management Drug OPIOID AGONISTS WITH HIGH EFFECTIVENESS fentanyl (Actiq, Abstral, Duragesic, Fentora, Lazanda, Onsolis, Oralet) hydromorphone (Dilaudid, Exalgo) levorphanol (Levo-Dromoran) meperidine (Demerol) morphine (Astramorph PF, Duramorph, others) oxymorphone (Opana) Route and Adult Dose (max dose where indicated) Transdermal patch: 25 mcg/h PO: 100 mcg initial dose (max: 100 mcg units provided at a time) Nasal spray: 100 mcg initial dose (max 800 mcg) Buccal transmucosal: 200 mcg initial dose (max: no more than six 200-mcg units should be in the patient s possession for titration) PO/Subcutaneous/IM/IV: 1 4 mg every 4 6 h prn PO: 2 3 mg tid qid prn Subcutaneous/IV: 1 2 mg q6-8h PO: mg q3 4h IM: mg q3 4h IV: mg/kg q3 4h PO: mg q4h prn Sustained release: mg q8 12h IM: 10 mg q4h IV: 2 10 mg q2 4h Subcutaneous: mg q4 6h Rectal: 1 suppository (5 mg) q4 6h PO (extended release): 5 20 mg bid Adverse Effects Pruritus, constipation, nausea, sedation, drowsiness, dizziness Anaphylactoid reaction, cardiac arrest, severe respiratory depression or arrest, convulsions, abuse potential

22 Table 18.3 Opioids for Pain Management (2 of 3) Table 18.3 Opioids for Pain Management Drug Route and Adult Dose (max dose where indicated) OPIOID AGONISTS WITH MODERATE EFFECTIVENESS codeine hydrocodone (Hycodan) oxycodone (OxyContin, Oxecta) OPIOID ANTAGONISTS PO: mg qid IM: mg q4 6h PO: 5 10 mg q4 6h prn (max: 15 mg/dose) PO: 5 10 mg qid prn Controlled release: mg q12h Adverse Effects Sedation, nausea, constipation, dizziness Hepatotoxicity, respiratory depression, circulatory collapse, coma, abuse potential naloxone (Evzio, Narcan) naltrexone (ReVia, Trexan, Vivitrol) IV: mg; may be repeated q2 3min up to 10 mg if necessary PO: 25 mg followed by another 25 mg in 1 h if no withdrawal response (max: 800 mg/day) Muscle and joint pain, sleep anxiety, headache, nervousness, withdrawal symptoms, vomiting, diarrhea, insomnia Hepatotoxicity

23 Table 18.3 Opioids for Pain Management (3 of 3) Table 18.3 Opioids for Pain Management Drug Route and Adult Dose (max dose where indicated) OPIOIDS WITH MIXED AGONIST ANTAGONIST EFFECTS buprenorphine (Buprenex, Butrans, Suboxone) butorphanol (Stadol) dezocine (Dalgan) IM/IV: 0.3 mg q6h (max: 0.6 mg q4h) Topical: one patch every 7 days Sublingual: mg/day IM: 1 4 mg q3 4h prn (max: 4 mg/dose) IV: mg (usually 5 mg) q2 4h IM: 5 10 mg (usually 10 mg) q3 4h Adverse Effects Drowsiness, dizziness, lightheadedness, euphoria, nausea, clammy skin, sweating, insomnia, abdominal pain, constipation Respiratory depression, shock nalbuphine (Nubain) pentazocine (Talwin) Subcutaneous/IM/IV: mg q3 6h prn (max: 160 mg/day) PO: mg q3 4h (max: 600 mg/day) Subcutaneous/IM/IV: 30 mg q3 4h (max: 360 mg/day) Note: Italics indicate common adverse effects; underlining indicates serious adverse effects.

24 Opioid Agonists Mechanism of action: to interact with specific receptors Primary use: to relieve moderate to severe pain; some used for anesthesia Examples: OxyContin, Percocet

25 Opioid (Narcotic) Agonist Prototype drug: Opioid agonists morphine (Astramorph PF, Duramorph, others) Mechanism of action: interacts with mu and kappa receptor sites

26 Opioid (Narcotic) Agonist Primary use: for analgesia and anesthesia Adverse effects: respiratory depression, sedation, nausea, and vomiting

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29 Opioid Antagonists Block opioid activity Compete for opioid receptor Reverse symptoms of addiction, toxicity, and overdose Naloxone (Evzio, Narcan) may be used to reverse respiratory depression and other acute symptoms Also used to diagnose overdose

30 Opioid Antagonists Prototype drug: naloxone (Evzio, Narcan) Mechanism of action: interact with receptors Primary use: to reverse respiratory depression and other acute symptoms of opioid addiction, toxicity, overdose

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32 Role of the Nurse: Opioid Antagonist Therapy Continue careful monitoring of patient's condition Especially respiratory status Have resuscitative equipment available

33 Opioids with Mixed Agonist- Antagonist Activity Stimulate opioid receptor, thus causing analgesia Withdrawal symptoms and side effects not as intense as those of opioid agonists Example: pentazocine (Talwin)

34 Opioid Dependence Potential to cause physical and psychologic dependence Patient-controlled analgesia (PCA) Combinations with nonnarcotic analgesics

35 Vicodin: Hydrocordone 5mg, acetaminophen 500mg Percodan:Oxycodone hyrdochloride 7.5mg acetaminophen 325 mg)

36 Treatment for Opioid Dependence Switch from IV and inhalation forms to methadone, the oral form Methadone maintenance Does not cure but avoids withdrawal symptoms Treatment may be needed for many months or years

37 Newer Treatment Early treatment: buprenorphine (Buprenex, Butrans, Suboxone) Mixed opioid agonist-antagonist Sublingual or transdermal route Later maintenance: bunavail, Suboxone, and Zubsolv contain both buprenorphine and naloxone

38 Role of the Nurse: Opioid Therapy Assess potential for opioid dependency Have narcotic antagonists available to reverse negative effects Monitor urine output for retention Monitor patient's bowel habits for constipation

39 Nonopioid Analgesics Used for fever, inflammation, and analgesia Used for mild or moderate pain associated with inflammation Include NSAIDs, acetaminophen, and a few centrally acting drugs

40 Table 18.4 Nonopioid Analgesics (1 of 3) Table 18.4 Nonopioid Analgesics Drug NSAIDs: ASPIRIN AND OTHER SALICYLATES Route and Adult Dose (max dose where indicated) Adverse Effects aspirin (acetylsalicylic acid, ASA) PO: mg q4h (max: 4 g/day) Heartburn, stomach pains, ulceration salsalate (Disalcid) NSAIDs: IBUPROFEN AND SIMILAR DRUGS diclofenac (Cambia, Cataflam, Voltaren, Zipsor) PO: 325 3,000 mg/day in divided doses (max: 4 g/day) PO: 50 mg bid qid (max: 200 mg/day) Bronchospasm, anaphylactic shock, hemolytic anemia Indigestion, nausea, occult blood loss, anorexia, headache, drowsiness, Dizziness diflunisal etodolac PO: 1,000 mg followed by 500 mg bid tid PO: mg tid qid fenoprofen (Nalfon) PO: 200 mg tid qid Aplastic anemia, drug-induced peptic ulcer, GI bleeding, agranulocytosis, laryngospasm, laryngeal edema; peripheral edema, anaphylaxis, acute renal failure; vomiting, constipation, Diarrhea flurbiprofen (Ansaid, Ocufen) PO: mg tid qid (max: 300 mg/day)

41 Table 18.4 Nonopioid Analgesics (2 of 3) Table 18.4 Nonopioid Analgesics Drug ibuprofen (Advil, Motrin, others) (see page 506 for the Prototype Drug box) indomethacin (Indocin, Tivorbex) ketoprofen (Actron, Orudis) ketorolac (Toradol) mefenamic acid (Ponstel) meloxicam (Mobic) Route and Adult Dose (max dose where indicated) PO: 400 mg tid qid (max: 1,200 mg/day) PO: mg bid tid (max: 200 mg/day), or 75 mg sustained release one to two times/day PO: mg tid qid PO: 10 mg qid prn (max: 40 mg/day) PO: Loading dose: 500 mg; Maintenance dose: 250 mg q6h prn PO: 7.5 mg/day (max: 15 mg/day) mg daily Adverse Effects nabumetone (Relafen) PO: 1,000 mg/day (max: 2,000 mg/day) naproxen (Naprelan, Naprosyn) PO: 500 mg followed by mg tid qid (max: 1,250 mg/day) naproxen sodium (Aleve, Anaprox, others) oxaprozin (Daypro) piroxicam (Feldene) sulindac (Clinoril) tolmetin (Tolectin) PO: mg bid (max: 1,000 mg/day naproxen) PO: 600 1,200 mg/day (max: 1,800 mg/day) PO: mg one to two times/day (max: 20 mg/day) PO: mg bid (max: 400 mg/day) PO: 400 mg tid (max: 2 g/day)

42 Table 18.4 Nonopioid Analgesics (1 of 3) Table 18.4 Nonopioid Analgesics Drug NSAIDs: COX-2 INHIBITORS celecoxib (Celebrex) CENTRALLY ACTING DRUGS acetaminophen (Tylenol, others) (see page 509 for the Prototype Drug box) Route and Adult Dose (max dose where indicated) PO: mg q6-8h or 200 mg qid PO: mg q4 6h (max 3g/day) tramadol (Ultram) PO: mg q4 6h prn (max: 400 mg/day); may start with 25 mg/day, and increase by 25 mg every 3 days up to 200 mg/day ziconotide (Prialt) Intrathecal 0.1 mcg/h via infusion, may increase by 0.1 mcg/h every 2 3 days (max: 0.8 mcg/h) Note: Italics indicate common adverse effects; underlining indicates serious adverse effects. Adverse Effects Abdominal pain, dizziness, headache, sinusitis, hypersensitivity Cautious use due to FDA review Hypotension, dry mouth, constipation, drowsiness, sedation, dizziness, vertigo, fatigue, headache Anaphylactic reaction, hepatotoxicity, hepatic coma, acute renal failure

43 Salicylates Prototype drug: aspirin (ASA) Mechanism of action: Inhibits prostoglandin synthesis by inhibiting cyclooxygenase (COX) Adverse effects: with high doses may cause GI distress and bleeding May increase action of oral hypoglycemic agents

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46 Nonsteroidal Anti-inflammatory Drugs (NSAIDs) Prototype drug: ibuprofen (Motrin) Mechanism of action: to inhibit cyclooxygenase and prevent formation of prostaglandins Primary use: for mild or moderate pain and to reduce inflammation Adverse effects: GI upset, acute renal failure

47 Selective Cox-2 Inhibitors Prototype drug: celecoxib (Celebrex) Mechanism of action: similar to the NSAIDs Primary use: to relieve pain, fever, inflammation Adverse effects: mild and related to GI system

48 Centrally Acting Nonopioid Analgesics Prototype drug: acetaminophen (Tylenol) Mechanism of action: to treat fever at the level of the hypothalamus; causes dilation of peripheral blood vessels, enabling sweating and dissipation of heat

49 Centrally Acting Nonopioid Analgesics Primary use: treatment of fever and to relieve pain Adverse effects: uncommon with therapeutic doses

50 Centrally Acting Nonopioid Analgesics Prototype drug: tramadol (Ultram) Mechanism of action: inhibits reuptake of serotonin and norepinephrine in spinal neurons. Primary use: as centrally acting analgesic Adverse effects can include: dizziness, lethargy, constipation

51 Role of the Nurse: Drugs for Control of Pain Assessment Carefully monitor patient's condition Assess vital signs, especially respiratory status Assess patient's pain level: character, duration, location, intensity of pain Obtain history of medications, alcohol use

52 Drugs for Control of Pain Planning Goal is to explain proper use of medication Patient is to be free of pain without dependency

53 Drugs for Control of Pain Implementation Encourage compliance with medication regimen

54 Drugs for Control of Pain Evaluation Patient should have pain control with limited side effects, no dependency

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58 Headache and Migraines Tension headache Most common Self-limiting annoyance rather than emergency Migraine Throbbing or pulsating pain Often causes nausea and vomiting Often have triggers that can be avoided

59 Goal for Migraine Therapy Stop migraines in progress Prevent migraines from occurring

60 Antimigraine Drugs Triptans Serotonin agonists Act by constricting certain intracranial vessels Ergot alkaloids Interact with adrenergic, dopaminergic, and serotonin receptors Act as vasoconstrictors Terminate ongoing migraines

61 Triptans Prototype drug: sumatriptan (Imitrex) Mechanism of action: to act as serotonin agonists, constricting certain intracranial vessels Primary use: to abort migraines Adverse effects: GI upset

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64 Ergot Alkaloids Mechanism of action: to promote vasoconstriction Primary use: to terminate ongoing migraines Adverse effects: GI upset, weakness in the legs, numbness and tingling in fingers and toes, angina-like pain, tachycardia

65 Other Drugs for Migraine Prophylaxis Antiseizure drugs Beta-adrenergic blockers Calcium channel blockers Tricyclic antidepressants

66 Table 18.5 Antimigraine Drugs (1 of 4) Table 18.5 Antimigraine Drugs Drug TRIPTANS Route and Adult Dose (max dose where indicated) almotriptan (Axert) PO: mg; may repeat in 2 h if necessary (max: 2 tabs/day) Adverse Effects Asthenia, tingling, warming sensation, dizziness, vertigo eletriptan (Relpax) PO: mg; may repeat in 2 h if necessary (max: 80 mg/day) Coronary artery vasospasm, MI, cardiac arrest frovatriptan (Frova) PO: 2.5 mg; may repeat in 2 h if necessary (max: 7.5 mg/day) naratriptan (Amerge) rizatriptan (Maxalt) sumatriptan (Imitrex) zolmitriptan (Zomig) ERGOT ALKALOIDS dihydroergotamine (D.H.E. 45, Migranal) PO: mg; may repeat in 4 h if necessary (max: 5 mg/day) PO: 5 10 mg; may repeat in 2 h if necessary (max: 30 mg/day); 5 mg with concurrent propranolol (max: 15 mg/day) PO: 25 mg for 1 dose (max: 100 mg) PO: mg; may repeat in 2 h if necessary (max: 10 mg/day) IM/subcutaneous: 1 mg; may be repeated at 1-h intervals to a total of 3 mg (max: 6 mg/wk) Nasal: 1 spray (0.5 mg) each nostril, may repeat once in 15 min Weakness, nausea, vomiting, abnormal pulse, Pruritus Delirium, convulsive seizures, intermittent Claudication

67 Table 18.5 Antimigraine Drugs (2 of 4) Table 18.5 Antimigraine Drugs Drug ergotamine (Ergostat), ergotamine with caffeine (Cafergot, Ercaf, others) ANTISEIZURE DRUGS Route and Adult Dose (max dose where indicated) PO: 1 2 mg followed by 1 2 mg every 30 min until headache stops (max: 6 mg/day or 10 mg/wk) Sublingual: 2 mg, may repeat in 30 min for total three doses/24 h or five doses/wk topiramate (Topamax) PO: start with 50 mg/day, increase by 50 mg/wk to effectiveness (max: 1600 mg/day) Adverse Effects Nausea, vomiting, sedation, drowsiness, Weakness valproic acid (Depakene) (see page 192 for the Prototype Drug box) BETA-ADRENERGIC BLOCKERS atenolol (Tenormin) (see page 422 for the Prototype Drug box) metoprolol (Lopressor) (see page 404 for the Prototype Drug box) propranolol (Inderal) (see page 453 for the Prototype Drug box) PO: 250 mg bid (max: 100 mg/day) PO: mg/day (max: 100 mg/day) PO: mg one to two times/day (max: 450 mg/day) PO: mg/day in divided doses; may need mg/day Liver failure, bone marrow depression Bradycardia, hypotension, heart failure (HF), confusion, drowsiness, insomnia Bronchospasm, exfoliative dermatitis, agranulocytosis, membrane irritation, rash, heart block, cardiac arrest, anaphylaxis, Stevens Johnson syndrome

68 Table 18.5 Antimigraine Drugs (3 of 4) Table 18.5 Antimigraine Drugs Drug timolol (Blocadren) (see page 871 for the Prototype Drug box) CALCIUM CHANNEL BLOCKERS nifedipine (Procardia) (see page 385 for the Prototype Drug box) nimodipine (Nimotop) verapamil (Isoptin SR) (see page 456 for the Prototype Drug Box) TRICYCLIC ANTIDEPRESSANTS Route and Adult Dose (max dose where indicated) PO: 10 mg bid; may increase to 60 mg/day in two divided doses PO: mg tid (max: 180 mg/day) PO: 60 mg q4h for 21 days; start therapy within 96 hours of subarachnoid haemorrhage PO: mg tid (max: 360 mg/day) Adverse Effects Dizziness, light-headedness, facial flushing, heat sensitivity, diarrhea, peripheral edema, headache, hypotension, constipation Myocardial infarction (MI), atrioventricular (AV) block, hepatotoxicity amitriptyline (Elavil) PO: mg/day Sedation, drowsiness, orthostatic hypotension, blurred vision, slight mydriasis, dry mouth, urinary retention, constipation imipramine (Tofranil) (see page 208 for the Prototype Drug box) protriptyline (Vivactil) PO: mg/day (max: 300 mg/day) PO: mg/day in three to four divided doses (max: 60 mg/day) MI, dysrhythmias, heart block, agranulocytosis, angioedema, bone marrow depression

69 Table 18.5 Antimigraine Drugs (4 of 4) Table 18.5 Antimigraine Drugs Drug MISCELLANEOUS DRUGS methysergide (Sansert) onabotulinumtoxin A (Botox) riboflavin (vitamin B2) Route and Adult Dose (max dose where indicated) PO: 4 8 mg/day in divided doses IM: 155 units administered intramuscularly (IM) to muscles of the head and neck area As a supplement: PO: 5 10 mg/day For deficiency: PO: 5 30 mg/day in divided doses Note: Italics indicate common adverse effects; underlining indicates serious adverse effects. Adverse Effects Nausea, vomiting, sedation, drowsiness, weakness, discoloration of urine (for vitamin B2), painful Urination Shortness of breath

70 Role of the Nurse: Antimigraine Therapy Obtaining medical history Obtaining list of allergies Assessing patient's pain level Obtaining history of medications and alcohol and CNS-depressant use Assessing frequency and intensity of the migraine headaches

71 Role of the Nurse: Antimigraine Therapy Providing a quiet, calm environment Applying cold packs to help lessen pain Assessing pain level before medication administration Monitoring for side effects

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