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ED Pain Management (and the Drug-seeking Patient) Grant Innes, MD Pain hurts! Objectives Acute pain vs. chronic pain Chronic pain vs. addiction Impact of pain biology on patient behaviour and response to therapy Basic concepts in pain Rx for ED patients who may be opioid dependent Pain management may be the most important thing we do, but . . . It is a secondary consideration for most physicians, We under-treat pain. We underutilize potent analgesics Trust me! I’m a doctor. Medical school time devoted to rare metabolic disorders . . . 400 hours Time devoted to studying pain and pain management . . . 1 hour Textbook of Surgical Analgesia Chapter 1. Parenteral analgesia Demerol 50-75 mg IM q4h prn Chapter 2. Oral Analgesia Tylenol #3, I-II tabs po q4h prn Case 1 An unkempt 32 year-old man presents with a severe toothache. His chart shows he was seen 2 days earlier and given a Rx for 20 Tylenol #3 tabs, which he says were ineffective. Your next step is: A. Call security B. Suggest OTC Tylenol, then call security C. Prescribe an unusual NSAID (“Idarac”) D. Give him 4 “T3” to go E. None of the above *** Treatment – Case 1 Infra-orbital nerve block Marcaine Xylocaine with epi Ibuprofen to start before the pain recurrs Tylenol to start when the pain recurrs Oxycodone Treating Acute Pain: The Modified WHO Pain Ladder Step 1: Acetaminophen Step 2: NSAID (ibuprofen) Step 3: Syndrome-specific agent “muscle relaxant” for back pain Dopamine antagonist for migraine Step 4: Opioid Pretend opioid (codeine) Real opioid (morphine, hydronorphone) Acute Pain Physiology (in 2 slides) Mechanical, thermal or chemical stimuli (with tissue injury) lead to local inflammatory mediator release Pain impulses transmitted to spinal cord At DRG: neuropeptides mediate sensitization pain threshold decreases, and central response to pain increases Antidromic conduction/recruitment To DRG Neurogenic inflammation Antidromic conduction and inflammatory mediator release Secondary hyperalgesia; recruitment Pain is a vicious cycle. Preempt it Acute pain: More biochemical than neural Migraine: An Inflammatory Syndrome Noxious triggers activate trigeminal nociceptors Trigeminal brainstem sensory complex receives input from 7,9,10,12 Antidromic trigeminal activation leads to release of vasoactive neuropeptides! Opioids Codeine (Tylenol #3): - Moderately effective - GI upset (low abuse potential) Meperidine: - Poorly absorbed. Shorter acting. AEs. Potent oral opioids: - Less GI upset - Effective but more euphoria/CNS effects - Potential for abuse Multimodal Analgesia Acetaminophen NSAIDs or COX-2 Opioids “Muscle relaxants” Cyclobenzeprine Methocarbamol Antidepressants Sedative-hypnotics Regional blocks Anticonvulsants Dopamine antagonists Antimigraine drugs Heat and Ultrasound Massage Acupuncture Alternative remedies Case 2: A young female, disabled by chronic leg pain (compartment syndrome), presents with a painful arm. When you pass by the bed, she moans and clutches her arm. She is on methadone for chronic pain and has told the nurse she will need 250 mg of Demerol because she has a “high pain threshold”. She is febrile and has a markedly swollen arm with multiple recent needle tracks. When you touch the skin lightly, she screams and pulls her arm away Q. The best treatment is: IV antibiotics + acetaminophen and ibuprofen Antibiotics + additional methadone Antibiotics + high-dose titrated IV morphine Antibiotics + 4 “Tylenol #3 to go” Vancouver, BC - 1.2 million people Canada’s richest postal code Canada’s poorest postal code St. Paul’s Hospital HIGH Prevalence of Opioid Addiction and Dependency Features of the Case She moans and clutches her arm—as you pass Drug-seeking behavior: She is communicating with you She is febrile with a +++ swollen arm. This is an acute exacerbation—not her steady state She says she needs 250 mg of Demerol Tolerance When you touch the skin lightly, she screams and pulls her arm away Allodynia Q. The best treatment is: IV antibiotics + acetaminophen + ibuprofen Antibiotics + additional methadone Antibiotics + high-dose titrated IV morphine Antibiotics + 4 “Tylenol #3 to go” A. For opioid dependent patients with unequivocal and uncontrolled pain, treat the pain aggressively Substance abuse disorder (Addiction) A complex neurochemical disorder that: causes behaviour patterns that are misunderstood and aggravating to ED staff makes it difficult for addicts to make constructive and rational decisions Substance abuse disorder Cognitive, behavioural and physiological symptoms Substance use despite significant related problems. At least three of the following: Tolerance; Withdrawal; Larger amounts and longer time periods than intended; Persistent desire or unsuccessful attempts to control use; Disproportionate time and effort to obtain the substance; Impact on social, occupational, or recreational activities Continued use despite health, social or economic problems Case 3: A middle-age woman presents with chronic upper back pain that is worse since a recent fall. Her oxycodone is not working and she hasn’t slept for 3 days. She feels she cannot manage at home and may need hospitalization. PMH: depression and fibromyalgia. Meds: Diclofenac (50 mg tid) and oxycodone (80 mg/day). Exam: She lies motionless in bed with her eyes closed. She is in no evident pain and appears depressed. She winces in pain when her skin is touched over the upper back, but there are no objective findings. Your treatment options might include: A. NSAIDs B. IV opioids D. Antidepressants C. Oral hydromorphone E. Other Features of the case She lies motionless in bed with her eyes closed. A complex neurochemical disorder causing behaviour patterns that are misunderstood and aggravating to ED staff She is in no evident pain Chronic pain does not look like acute pain She appears depressed. Depression travels with chronic pain She winces in pain when her skin is touched lightly over the upper back Allodynia Chronic pain Definition: Lasts longer than expected Ongoing pain increases the expression of CNS pain receptors that influence pain experience Allodynia and hyperalgesia • A chronic disease with exacerbations + remissions At steady state with their analgesics, unless change in disease status: may need dose increase w flareup Inflammation is a minor concern in chronic pain and an insignificant concern in neuropathic pain Chronic Pain doesn’t “look like” acute pain Acute pain: protective activation of the ANS Pallor, anxiety, tachy, diaphoresis, restless Chronic pain: Not inflammatory Minimal ANS activation Depression Directed combination therapy for chronic pain Simple analgesics NSAID if an acute component or chronic inflammatory state—not in neuropathic pain. Opioids often necessary but rarely sufficient as a single agent Consider opioid rotation (different opioid receptor subtypes respond to different drugs) For rapid analgesia, titrate short-acting agents If addictive tendency, consider longer acting or SR agents, with less euphoric effects and less intense W/D Treat related symptoms (e.g. anxiety, insomnia, depression) with specific agents Other “Analgesic” Options Dopamine antagonists and antimigraine drugs for HA “Muscle relaxants” (e.g. cyclobenzeprine, methocarbamol) Antidepressants (e.g. Amitryptiline, Trazodone) Anticonvulsants for neuropathic pain Sedative-hypnotics for anxiety Regional blocks Physical modalities (heat, US, massage, acupuncture) Alternative remedies Definitions Tolerance: Adaptation with diminished drug efficacy. Physical dependency: cessation causes withdrawal sx Addiction: maladaptive behavior including: loss of control, compulsive substance use, preoccupation with using a substance despite negative consequences. Pseudoaddiction: a behavioral response to inadequate pain control (perceived as drug seeking). Aberrant behavior ceases with appropriate pain management*. Note: Tolerance and dependency do not indicate addiction Differential Diagnosis: Chronic pain vs. addiction Overlap between chronic pain and addiction. Some chronic pain patients are addicted. No objective test to differentiate Non-addicts often display drug seeking behavior Hi likelihood of diagnostic error Important Findings—or not?? Dress and grooming? Appearance and vital signs? A lost prescription; out of meds; Asks for drugs and doses by name A tale of woe: many causes of pain Different opioids - different doctors Stable employment, family, and function Noncompliant with Rx plan Is it real, or . . . Using my best judgment, how patients with real pain will I refuse to treat? (assuming 80% sensitivity, 80% specificity and 5% prevalence of drug-seekers). Truth Addict Judgment Addict 40 Pain 190 230 PPV=17.4% Pain 10 760 770 NPV=98.5% 50 950 1000 Pts with pain of uncertain validity When in doubt . . . Treat the pain! Pain is what the patient says it is -- usually Old records and Pharmanet Frequent flyer (DMP) program: DMP committee develops an ED care protocol defining a consistent approach to subsequent ED visits. Plan is consistent with the pt’s overall care plan, and is printed automatically at triage each time the pt comes to ED. Pts with no primary care provider are referred to one Pts likely to benefit from other expertise (e.g. psychiatry, chronic pain service) are referred during their next ED visit Summary Acute pain concepts: Neurogenic inflammation Multimodal analgesia Chronic pain concepts Cognitive/behavioural changes. Depression Loss of autonomic activation. Hyperalgesia and allodynia Directed combination therapy Tolerance and dependency = addiction Pain is (usually) what the patient says it is Speaker Pain Management and theEvaluations Drug-Seeking Patient (Innes) How would you rate this presentation? A. Excellent!! This was the finest educational experience I’ve ever had—by far! B. Superb! The speaker was incredible. This information will change my practice dramatically for the better. C. Outstanding! It scares me how I was practicing medicine before I saw this presentation D. Fair. Please report me to the FBI for fraudulent billing practices Opioid Equianalgesic Data Opioid Parenteral (mg) Oral (mg) Morphine 10 30* Hydromorphone 1.5 7.5 Oxycodone --- 20 Codeine 130 200 Fentanyl 0.1^ --- Methadone --- 3-5 The Causes of Drug-Seeking Commerce: To acquire drugs to sell Misuse: Using drugs for euphoric effect Inadequately treated acute pain Inadequately treated chronic pain