Pain Management Lecture 2024 PDF

Pain Management Brunner & Suddarth’s Textbook of Medical-Surgical Nursing 14th ed. Chapter 12. (p 225)  Definition of Pain Pain: Unpleasant sensory and emotional experience resulting from actual or potential tissue damage. This definition describes pain as a complex...

Pain Management Brunner & Suddarth’s Textbook of Medical-Surgical Nursing 14th ed. Chapter 12. (p 225)  Definition of Pain Pain: Unpleasant sensory and emotional experience resulting from actual or potential tissue damage. This definition describes pain as a complex phenomenon that can impact a person’s psychosocial, emotional, and physical functioning. Pain ―whatever the experiencing person says it is, existing whenever she/he says it does‖. McCaffery, 1968 It is a subjective experience.  Effects of Pain Can affect every age, sex, race & socioeconomic class The primary reason people seek health care Unrelieved pain can affect every system in the body This is particularly harmful in patients whose health is already compromised by age, illness, or injury. Effects of Pain Effects of Pain  Types and categories of Pain I. Acute pain – Recent onset & associated with a specific injury – have a relatively short duration, resolve with normal healing. – Decreases as healing occurs. – example of acute pain: tissue damage as a result of surgery, trauma, or burns produces II. Chronic pain – either due to cancer or noncancer origin – may resolve within months or persist throughout the course of a person’s life. – Constant or intermittent, persists beyond the expected healing time & seldom be attributed to a specific cause or injury. – Poorly defined onset, Difficult to treat (unclear cause). – examples of noncancer pain: peripheral neuropathy from diabetes, back or neck pain after injury, and osteoarthritis pain from joint degeneration.  Types and categories of Pain Some conditions can produce both acute and chronic pain. – For example, some patients with cancer have continuous chronic pain and also experience acute exacerbations of pain periodically— called breakthrough pain (BTP)—or Endure acute pain from repetitive painful procedures during cancer treatment.  Types and categories of Pain According to inferred pathology I. Nociceptive (physiologic) pain refers to the normal functioning of physiologic systems that leads to the perception of noxious stimuli (tissue injury) as being painful ―normal‖ pain transmission. a. Somatic pain - Arises from bone, joint, muscle, skin - Described as aching or thrombing pain - Well localized - E.g., surgical, trauma, wound and burn burn, labor pain, rheumatoid arthritis b. Visceral pain: arises from visceral organ ( GIT, Panaceas); e.g., ulcerative colitis crohn’s disease, pancreatitis.  Types and categories of Pain II. Neuropathic (pathophysiologic) pain is pathologic and results from abnormal processing of sensory input by the nervous system as a result of damage to the peripheral or CNS or both. Neuropathic pain may be associated with abnormal sensations called dysesthesia or pain from normally non-painful stimuli (allodynia). – Phantom pain: a result of peripheral nerve damage, post stroke pain, pain following spinal cord injury pain that feels like it's coming from a body part that's no longer there Endorphin is a hormone that your body produces to ease pain and make you feel calm and happy."natural pain killers"  Types and categories of Pain Patients may have a combination of nociceptive & neuropathic pain.  For example:  Pain from tumor growth>>> nociceptive pain & if pt report radiating pain due to pressure against nerve plexus >>> neuropathic pain  Sickle cell disease pain is usually a combination of nociceptive pain from the clumping of sickled cells and resulting perfusion deficits, and neuropathic pain from nerve ischemia.  Pain pathway Nociception: the process by which information about tissue damage is conveyed to the CNS. 1) Transduction: the conversion of the energy from a noxious stimulus into electrical energy (nerve impulses) by sensory receptors called nociceptors 2) Transmission: the transmission of these neural signals from the site of transduction (periphery) to the spinal cord and brain 3) Perception: the appreciation of signals arriving in higher structures as pain 4) Modulation: descending inhibitory and facilitory input from the brain that influences (modulates) nociceptive transmission at the level of the spinal DR. Ahmad Aqel 13 cord.  Pain pathway What happens during transduction?  Damaged cells release mediators of inflammation (prostaglandins, substance P, bradykinin, histamine, serotonin, cytokines). Nociceptor activation: Nociceptors are sensory receptors that are sensitive to tissue trauma or a stimulus. Signals from these nociceptors travel along two fiber types: unmyelinated C-fibers, slowly conducting myelinated A-delta fibers, rapidly conducting  Pain pathway What happens during transduction? Clinical implications Some analgesics target the inflammatory process such as NSAIDs inhibit cyclooxygenase (COX), thus decreasing the synthesis of prostaglandins. Other analgesics (antiepileptic drugs, local anesthetics) block channels, thus inhibiting the generation of nerve impulses. DR. Ahmad Aqel 15  Pain pathway What happens during transmission?  Nerve impulses are transmitted to the spinal cord and brain in several phases: Periphery to the spinal cord: Spinal cord to the brain Clinical implications Some analgesics inhibit signals in the dorsal horn (DH). For example, opioid analgesics bind to opioid receptors on primaryDR.afferent Ahmad Aqel and DH neurons. 16  Pain pathway What happens during perception?  Information from some dorsal horn (DH) projection neurons travels via the thalamus to the somatosensory cortex, where information about the location, intensity, and quality of the pain is identified. DR. Ahmad Aqel 17  Pain pathway What happens during modulation?  Descending pathways - The reduction of DH transmission by descending inhibitory input from the brain.  Nerve fibers release inhibitory substances (endogenous opioids, norepinephrine) that bind to receptors inhibit transmission.  Clinical implications Some analgesics enhance the effects of descending inhibitory input. For example, some antidepressants are used to treat some types of chronic pain. DR. Ahmad Aqel 18 DR. Ahmad Aqel 19  Pain assessment Assess posture and pain behaviors. Ask the patient to describe pain in own words Factors to consider in pain assessment – intensity, timing, location ,quality, personal meaning of pain; aggravating and alleviating factors; and pain behaviors. Questions to assess pain Where is the pain located? How long does it last? How often does it occur? How would you describe the pain? What brings the pain on? What relieves the pain or makes it worse? What do you think is causing your pain? What do you fear most about the pain? What problems does the pain cause you? Who else have you consulted about the pain? Family members? What treatments do you think might help you with the pain?  Pain assessment  Patient’s self report is the standard for assessing the existence and intensity of pain.  HCPs do not have the right to deprive any patient of appropriate assessment and treatment because they believe a patient is not being truthful.  Pain is reassessed and documented on a regular basis to evaluate the effectiveness of treatment.  At a minimum, pain should be reassessed with each new report of pain and before and after the administration of analgesic agents DR. Ahmad Aqel 22 Assessment include: o Location of pain, radiation of pain. o Intensity (severity): using a reliable and valid pain assessment tool, e.g., numerical rating scale & FACES pain scale, visual analog scale). DR. Ahmad Aqel 23 o Quality (e.g., “sharp,” “shooting,” or “burning”…to identify neuropathic pain) DR. Ahmad Aqel 24 Onset and duration when started? constant or intermitted? Aggravating and what make it worse or better? relieving factors Effect of pain on function and quality of life Comfort-function (pain (e.g., being able to sleep) intensity) goal Other information The patient’s culture, past pain experiences, perception and meaning of pain, distress that it cause, and medical history such as comorbidities, laboratory tests, and diagnostic studies DR. Ahmad Aqel 25  Pain assessment tools FLACC: indicated for use in young children. Scores are assigned after assessing Facial expression, Leg movement, Activity, Crying, and Consolability, with each of these five categories assigned scores from 0 to 2, yielding a total composite score of 0 to 10. PAINAD (Pain Assessment IN Advanced Dementia): indicated for use in adults with advanced dementia who are not able to verbalize their needs. CPOT (Critical Care Pain Observation Tool): indicated for use in patients in critical care units who cannot self-report pain, hether or not they may be intubated DR. Ahmad Aqel 26 Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Reassessing Pain Following initiation of the pain management plan, pain is reassessed and documented on a regular basis to evaluate the effectiveness of treatment. At a minimum, pain should be reassessed with each new report of pain and before and after the administration of analgesic agents DR. Ahmad Aqel 27 Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins  Pain Management Routes of Administration I. Oral route: the preferred, least expensive, best tolerated, and easiest to administer For patients who cannot swallow or NPO (nothing by mouth [nil per os]) or nauseated, II. Intravenous (IV) III. Rectal contraindications: neutropnic, thrombocytopenic (can cause bleeding) diarrhea, perianal abscess or fistula 28  Routes of Administration IV. Topical (applied to body surfaces such as the skin or mucous membranes) o Intraspinal (a needle in the subarachnoid space (for intrathecal [spinal] analgesia) or the epidural space). Most commonly used drugs are morphine, and hydromorphone DR. Ahmad Aqel 29  Video https://www.youtube.com/watch?v=2tw- SXI3wKU DR. Ahmad Aqel 30  Pain Management Dosing Regimen: o Goal: preventing pain and maintaining a pain intensity that allows the patient to accomplish functional or quality-of-life goals with relative ease o To achieve this goal: 1- Around-the-clock (ATC) medication is defined as medication that is given at regularly scheduled intervals (for patients who have pain more than 12 hours per 24 hours) 2- PRN (as needed) [pro re nata].(for intermittent pain, break through pain) o Patients with persistent pain in the hospital setting should be awakened to take their pain medication. DR. Ahmad Aqel 31  Pain Management Patient-Controlled Analgesia (PCA) o allows patients to treat their pain by self-administering doses of analgesic agents. Is programmed so that the pt can press the button to self-administer a dose of drug at a set time interval as needed DR. Ahmad Aqel 32  Pain Management: Pharmacologic Management  Pain may requires more than one analgesic agent (multimodal analgesia) o combines drugs with different underlying mechanisms, o allows lower doses of each of the drugs multimodal analgesia can result in comparable or greater pain relief than can be achieved with any single analgesic agent DR. Ahmad Aqel 33 Dosing Regimen Two basic principles of providing effective pain management are preventing pain and maintaining a pain intensity that allows the patient to accomplish functional or quality-of-life goals with relative ease. A preventive approach to pain management, also called ATC management, is designed to prevent pain from being experienced. Patients with persistent pain in the hospital setting should be awakened to take their pain medication. Awakening postoperative patients with moderate to severe pain to take their pain medication is especially important during the first 24 to 48 hours after surgery to keep pain under control. DR. Ahmad Aqel 34 Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins  Pain Management Three groups of analgesic agents (1) Nonopioid : acetaminophen and NSAIDs (2) Opioid : morphine, hydromorphone, fentanyl, and oxycodone (3) Adjuvant (‫ )مساعد‬agents: local anesthetics, some anticonvulsants and antidepressants.  Adjuvant analgesics are defined as drugs with a primary indication other than pain that have analgesic properties in some painful conditions DR. Ahmad Aqel 35 Analgesic Agents Nonopioid Analgesic Agents. Opioid Analgesic Agents Addiction, Physical Dependence, and Tolerance. Adjuvant Analgesic Agents. Local Anesthetics Anticonvulsants. Antidepressants Ketamine DR. Ahmad Aqel 36 Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins  Nonopioid Analgesic Agents  acetaminophen and NSAIDs  used for painful conditions,  Used for mild to moderate nociceptive pain (e.g., surgery, trauma, or osteoarthritis)  often combined with opioids, local anesthetics, and/or anticonvulsants for more severe nociceptive pain.  These combination drugs are not appropriate for severe pain (because the maximum daily dose of the nonopioid limits the escalation of the opioid dose)  NSAIDS and Acetaminophen can be given at the same time For example Acetaminophen recommended dose is 1,000 mg every 6 hours (for pt weighted more than 50 kg) if you need more you can take it with NSAIDS DR. Ahmad Aqel 37  Nonopioid Analgesic Agents  Acetaminophen  safe and well tolerated.  serious complication of overdose is hepatotoxicity  NSAIDs  adverse effects:  gastric toxicity and GI ulceration.  For protection: add a PPI (Proton Pump Inhibitor).  NSAIDs carry a risk of CV adverse effects through prostaglandin inhibition.  Most NSAIDs increase bleeding time though inhibition of COX-1.  adequate hydration is essential when giving NSAIDS to prevent complications (renal failure) DR. Ahmad Aqel 38  Opioid Analgesic Agents  Two major groups: 1. mu agonist opioids agonist-antagonist opioids: “mixed” because they bind to more than one opioid receptor site. They bind as agonists, producing analgesia, at the kappa opioid receptor sites, and as weak antagonists at the mu opioid receptor sites.  Mu agonist opioids  morphine, hydro-morphone, hydrocodone, oxycodone methadone & fentanyl, heroin, codeine, meperidine, and fentanyl.  Opioid bind to mu opioid receptors that are located throughout the body.  side effects: constipation, nausea, sedation, and respiratory depression.  Antagonist of opioids is NALOXONE. DR. Ahmad Aqel 39  Opioid withdrawal syndrome:  Occurring in sudden discontinuation or dosage reduction  The risk of a discontinuation syndrome occurring increases with dosage and length of use  Characterized by: rhinitis, abdominal cramping, nausea, agitation, and restlessness. DR. Ahmad Aqel 40 The dose and analgesic effect of mu agonist opioids have no ceiling effect, although the dose may be limited by adverse effects. Ceiling effect: the phenomenon in which a drug reaches a maximum effect, so that increasing the drug dosage does not increase its effectiveness The severity of side effects from a medication increases as the dose increases, long after its therapeutic ceiling has been reached. DR. Ahmad Aqel 41  Factors affect choosing appropriate pain medication  Age, pain intensity, other diseases patient have, drug interactions, patients preferences. Medicine titration :  gradually adjusting the dose of a medication until optimal results are reached. It may be upward or downward DR. Ahmad Aqel 42  Equianalgesia “equal analgesia”: approximate the same pain relief when switching route. Opioid Oral Parenteral Morphine 30mg 10mg DR. Ahmad Aqel 43 Formulation Terminology. The terms short acting, immediate release, and normal release have been used interchangeably to describe oral opioids that have an onset of action of approximately 30 minutes and a relatively short duration of 3 to 4 hours. The terms modified release, extended release, sustained release, controlled release, and long acting are used to describe opioids that are formulated to release over a prolonged period of time. DR. Ahmad Aqel 44 Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Physical Dependence, Tolerance, Addiction, Physical dependence:  occurs with repeated administration of the opioid for 2 or more weeks.  manifested by occurrence of withdrawal symptoms when the opioid is suddenly stopped or rapidly reduced or an antagonist such as naloxone is given.  decrease withdrawal symptoms by systematic reduction of the medication (tapering) DR. Ahmad Aqel 45 Tolerance:  occur with regular administration of an opioid  a decrease in effects of the opioid occurs in the first 2 weeks.  May be treated by increase the dose. Addiction:  characterized by: weak control over drug use, compulsive use, continued use despite harm, and cravings to use for effects other than pain relief. Pseudo-addiction: false diagnosis as an addictive, when the patient’s pain is not well controlled, the pt may begin manifested like addictive symptoms DR. Ahmad Aqel 46 Selected Opioid Analgesic Agent  Morphine  has a slow onset (it is hydrophilic), long duration of action  Good for cancer pain  Morphine has 2 metabolits: M3G (accumulation may produce neurotoxicity) and M6G (pain relief)  Fentanyl  is a lipophilic opioid, fast onset and short duration of action (good for procedural pain).  produces minimal hemodynamic (blood pressure, pulse) adverse effects and thus, it is often preferred in patients who are hemodynamically unstable, such as the critically ill.  can be used for pt with organ failure because it has no clinically relevant metabolits. DR. Ahmad Aqel 47 Dual-Mechanism Analgesic Agents: (e.g., tramadol) Single tablet produces an effect on more than one analgesic action site. These drugs bind weakly to the opioid receptors and block the reuptake of the inhibitory neurotransmitters serotonin and/or norepinephrine. DR. Ahmad Aqel 48  Adverse effects to opioids use  Constipation: The most common adverse effects (to prevent give stool softener )  Nausea, vomiting  Pruritus, and sedation  Respiratory depression (to prevent careful titration, close monitoring, dose reduction).  If respiratory depression is a concern administer the opioid antagonist, naloxone IV. DR. Ahmad Aqel 49  Adjuvant Analgesic Agents  Local Anesthetics:  safe & effective.  Such as Lidocaine patch 5%; put for 12 hours then without for 12 hours and repeat if needed,  signs of toxicity in CNS: ringing in ears, metallic test, irritability, and seizure, in Cardiac: numbness, bradycardia, dysrhythmia.  Anticonvulsants: such as gabapentin, (may be used after surgery amputation) some side effects: sedation and dizziness. DR. Ahmad Aqel 50 Antidepressants.  Two major groups: 1. the tricyclic antidepressants (TCAs)  side effects: dry mouth, sedation, dizziness, mental clouding, weight gain,  serious side effects : cardiotoxicity (not for pt with cardiac problems), and orthostatic hypotension 2. the serotonin and norepinephrine reuptake inhibitors (SNRIs).  The delayed onset of action makes this medication inappropriate for acute pain treatment. Ketamine.  Anesthetic with dose-dependent analgesic, sedative and amnestic properties. DR. Ahmad Aqel 51  Use of Placebos Placebo : any medication or procedure, including surgery, that produces an effect in a patient but not because of its specific physical or chemical properties. A saline injection is one example of a placebo. DR. Ahmad Aqel 52  Non-pharmacologic Methods of Pain Management Category Examples Body-based Proper body alignment; application of (physical) heat or cold,; massage, transcutaneous modalities nerve stimulation (TENS); acupuncture, aqua therapy Mind-body Relaxation breathing, litening, singing, (cognitive music, imagery, humor, prayer, behavioral)methods mediation, hypnosis Biological based Taking herbs, vitamins, proteins therapies Energy therapy yoga DR. Ahmad Aqel 53  NONPHARMACOLOGIC INTERVENTIONS Massage – Massage also promotes comfort because it produces muscle relaxation. Thermal Therapies – Application of heat increases blood flow to an area and contributes to pain reduction by speeding healing and provide some analgesia, Transcutaneous Electrical Nerve Stimulation – (TENS) uses a battery-operated unit with electrodes applied to the skin to produce a tingling, vibrating, or buzzing sensation in the area of pain.  NON-PHARMACOLOGIC INTERVENTIONS Distraction – focusing the patient’s attention on something other than the pain, to reduce the perception of pain Relaxation Techniques – abdominal breathing at a slow, rhythmic rate. The patient may close both eyes and breathe slowly and comfortably. Guided Imagery – The nurse instructs the patient to close both eyes and breathe slowly in and out. With each slowly exhaled breath, the patient imagines muscle tension and discomfort being breathed out, carrying away pain Hypnosis, Music Therapy Acupuncture is a treatment derived from ancient Chinese medicine in which fine needles are inserted at certain sites in the body for therapeutic or preventative purposes Aquatic therapy refers to water- based treatments or exercises of therapeutic intent, in particular for relaxation, fitness, and physical rehabilitation. DR. Ahmad Aqel 56 Humor therapy is the art of using humor and laughter to help heal people with physical or mental illness Hypnosis it allows people to explore painful thoughts, feelings, and memories they might have hidden from their conscious minds Prayer DR. Ahmad Aqel 57  Cordotomy – the division of certain tracts of the spinal cord – It may be performed percutaneously, by the open method after laminectomy, or by other techniques. – Cordotomy is performed to interrupt the transmission of pain. Rhizotomy Sensory nerve roots are destroyed where they enter the spinal cord. A lesion is made in the dorsal root to destroy neuronal dysfunction and reduce nociceptive input. 1- Comprehensive pain assessment 2- Give analgesia 3- Advice nonpharmacologic interventions 4- Assess and treat adverse effects 5- Educate patient and family DR. Ahmad Aqel 60