PAIN MANAGEMENT
| CUTTING-EDGE SEDATION AND PAIN REDUCTION IN THE ED—Sam Torbati, MD, Clinical Instructor in Medicine,
David Geffen School of Medicine at the University of California, Los Angeles
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| Procedural sedation: formerly called “conscious sedation”; tech-nique of administering sedatives or dissociative agents,
with or without analgesia, to induce state that allows patient to tolerate unpleasant procedure while maintaining cardiorespiratory
function; patients maintain oxygenation and overall airway control independently; moderate sedation—
involves drugs that depress consciousness, but patient responds purposefully; deep sedation—needed by some patients
because procedure more “unpleasant” (know before procedure); general anesthesia—use in emergency department
(ED) usually not intended, but if enough drug given fast enough, patient becomes generally anesthetized;
dissociative sedation—occurs with medications such as ketamine; patient in trancelike cataplectic state characterized
by profound analgesia and amnesia
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 | Principles: assess patient medically and psychosocially; psychosocial factors important (because patients experience pain
differently) and helpful when deciding which drug to use, how deep to take patient, and how patient might tolerate procedure;
important to titrate up to desired dose; some patients more sensitive or resistant to same medication; monitor
patients using hospital protocol; anticipate potential problems by knowing possible drug complications
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| Medical evaluation: history—to avoid hazardous drug interactions, know patient’s medical and analgesic history, ie,
which medicines patient taking, allergies, and previous adverse drug reactions; airway anatomy—look for mandibular
hypoplasia, large jaw or tongue (deep sedation may result in obstruction; transient ventilation potentially difficult); patients
who are difficult to bag include patient’s with beards (bag does not seal tightly), older patients, and patients without
teeth (potential for tongue to obstruct airway); monitoring—use appropriate equipment and guidelines; American Society
of Anesthesiologists (ASA) score—grades health of patient (healthy patients have ASA scores of 1-2); consider
ASA category when sedating patients; npo status—ASA guidelines for general anesthesia involve 2 hr fasting or clear
liquids and 6 hr for other fluids; studies suggest safe to place patient under procedural sedation without such strict guidelines;
recent food intake not contraindication, but consider when deciding how deep to take patient; assess risk-benefit
profile; studies in pediatric patients suggest gastric transit time in most healthy children 1 hr
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Pharmacologic Agents
| Fentanyl plus midazolam (Versed): fentanyl (powerful opiate) combined with midazolam (sedative); predetermined
dosing for intravenous (IV) and intramuscular (IM) use in pediatric and adult patients; combination produces synergistic
sedative and potentially adverse effects; use naloxone (Narcan) to reverse fentanyl; push flumazenil if patient experiences
respiratory depression
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| Barbiturates: methohexital (Brevital)—provides excellent sedation, anxiolysis, and amnesia; dose for ED sedation 1
mg/kg; sedation occurs within 1 cycle of blood flow; make sure to push drug to get rapid effect (lipophilic, so moves into
adipose and muscle tissue if not given fast enough); short duration of action makes it ideal for short procedure that requires
deep sedation (eg, reduction of shoulder, hip, knee); adverse effects—include respiratory depression, apnea, and
hypotension; contraindicated in patients with seizure disorders, porphyria, or allergies; no reversal agent; effect lasts 2 to
5 min; consider bagging patients before they come back up if deep sedation required; study reported 10% apnea rate that
required transient bag-valve-mask ventilation (patients who abuse alcohol more susceptible); pentobarbital—studies
focus mostly on pediatric population; similar properties to methohexital but much longer duration of action (60 min; reason
not used in adults); consider use in children during scanning procedures; study of children found 19% of head computed
tomography (CT) completed successfully (sedation long enough for CT) with midazolam; success rate with
pentobarbital 97%
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| Ketamine: derivative of phencyclidine (PCP); dissociative agent; typical doses maintain child’s airway reflexes; high
doses provide general anesthesia; IV 1 to 2 mg/kg and IM 3 to 4 mg/kg provides protection of airway reflexes; adverse
effects—emergence phenomenon (hallucinations or nightmares; adjunctive use of benzodiazepine reduces effect); catecholamine
surge associated with tachycardia and hypertension; contraindicated in children with cardiac disease, ventricular
septal defect (VSD), intracranial or intraocular issues (eg, trauma patient); respiratory depression and laryngospasm
rare; increased airway secretions or hypersalivation can occur; can premedicate with atropine or glycopyrrolate before
giving agent; contraindications—avoid use in children <3 mo of age and in patients with active pulmonary infection,
cardiovascular disease, uncontrolled hypertension, traumatic brain injuries, glaucoma, or attention-deficit disorder; complication
rates—airway problems 1.4% (manage by repositioning airway [eg, tilting chin], blow-by O2 , suction); rate
of respiratory depression 1% to 2%; postprocedure emesis rate 2% to 10% (warn parents)
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| Etomidate: used in induction for rapid sequence intubation (RSI); excellent for procedural sedation; has sedative and amnestic
properties; brief duration of action; associated with few cardiovascular side effects and no changes in intracranial
or intraocular pressure; study found time to sedation 15 min, compared to 32 min for midazolam; rapid onset and recovery;
good drug for short procedure; dosing for procedural sedation 0.1 mg/kg, one third of dose for RSI; study comparing
etomidate to pentobarbital for sedation during head and neck imaging showed etomidate not as successful as pentobarbital
because etomidate too short-acting; consider pentobarbital if CT slow or if transit issues make getting CT longer
process
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| Propofol: excellent sedation and amnesia; smooth recovery, without nausea and vomiting; quick onset and short duration;
can rebolus or maintain with infusion; produces deep sedation; study found adverse effect rate ≈10%
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| PAIN IN THE ACUTE SETTING —Dan Burkhardt, MD, Assistant Professor, Department of Anesthesia and Perioperative
Care, University of California, San Francisco, School of Medicine
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| Respond well to opiates: acute pain—eg, broken bone, surgical incision; highly variable intensity and short duration;
great fear of respiratory depression (consider allowing patient to experience short-term pain to avoid respiratory depression
from too much pain medication); cancer pain—pain characterized by relatively steady intensity; less fear of
respiratory depression; patient expects to get enough opiates to alleviate pain, regardles of impact on respiration
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| Do not respond well to opiates: chronic nonmalignant pain—eg, headache, back pain; substantial component of anxiety
and depression; opioid tolerance common and function of age (young adults rapidly develop tolerance to opioids,
elderly do not); neuropathic pain—eg, shingles, complex regional pain syndromes; poor response to opiates, even in
acute setting; substantial component of anxiety and depression; pain related to anxiety and depression not relieved by
opiates; long-term opiate users exhibit hyperalgia because of pain upregulation by opioids
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| Opiates: use in patient populations where they have provided good pain relief with little adverse effects or toxicity; among
safest medicines available (little organ damage); do not cause renal failure, bronchospasm, or hyperthyroidism, except in
extremely high doses; continue use in acute pain patients who have adequate pain control and are reaching functional
goals; side effects—itching, nausea, ileus, urine retention, dysphoria, somnolence, respiratory depression, and myoclonus
in intubated patients; spectrum of side effects (ie, from awake and in pain, to awake and comfortable, to nauseous and
itchy, to somnolent, to death from respiratory depression); patients moved along spectrum by changes in opiate dose;
changing pain intensity also has same effect as changing opiate dose; altering opioid dose because of fluctuations in pain
intensity can lead to opioid-induced toxicity that can result in respiratory arrest
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| Respiratory depression: diagnosis—requires monitoring O2 and CO2 levels; can monitor O2 absorption with pulse
oximetry, but no way to noninvasively monitor CO2 excretion; no accurate noninvasive test to diagnose respiratory acidosis;
respiratory rate has little to no correlation with acidosis; avoid using respiratory rate to rule out respiratory depression;
normal respiratory rate does not rule out opioid-induced respiratory depression; arousability only useful test; must
monitor both PaO 2 and arousability; in absence of hypoxia, acidosis well tolerated; even if blood gas shows pH 6.8 and
PaCO 2 120 mEq/L, as long as PaO 2 acceptable, patient will recover uneventfully; prophylactic oxygen—can protect
patient from hypoxia; consider use to buy time to detect and treat hypoxia before permanent injury occurs
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| Opioid toxicity: treatment—slowly give low-dose naloxone in patients with stable vital signs; if airway not secure, or
vital signs not stable, or oxygen saturation not adequate, give large dose naloxone (anticipate sudden catecholamine surge
and opiate reversal); consider giving one tenth of 0.4-mg ampule (40 µg) at time if unsure whether patient experiencing
opiate-induced somnolence; naloxone shorter acting than any opioid outside of operating room (OR); consider small dose
of naloxone as diagnostic test for opiate-induced somnolence; naloxone does not cause pain, naloxone overdose causes
pain; carefully titrated doses of naloxone not observed to cause pulmonary edema; risk factors—morbid obesity, sleep
apnea, concomitant use of sedatives, especially benzodiazepines (react synergistically with opioids); rapidly changing
acute pain, especially when treated with long-acting opioids (recommend short-acting agent to match rapidly changing
pain intensity); managing at-risk patients—have standardized assessments for oxygen saturation and arousability and
check respiratory rate; give prophylactic oxygen to patients at risk; use continuous pulse oximetry in patients at high risk
(requires 1 on 2 nursing ratio or intensive care unit [ICU] monitoring for greatest reliability)
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| Acute pain management: if patient has pain and no opiate side effects, increase dose; if patient has side effects and little
pain, decrease opioid dose; acute pain problem defined as pain plus opiate side effects; if patient has both pain and
side effects, consider changing opioids, adding nonopioid adjuncts (eg, anti-inflammatory agent, neuropathic pain medication,
α-2 agonist, local anesthetic); use as many adjuncts as necessary
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| Opioid dose equivalency: because of substantial individual variability, be wary of dose equivalency tables when
changing opioids, converting IV to oral medications, and comparing one patient to another; think of high, medium, and
low doses for each drug; start new drug at low dose, then reduce old drug until pain worsens, then increase new drug until
pain controlled, and repeat until conversion complete
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| Rational titration of opioids: use as many nonopioid adjuncts as possible round-the-clock; use short-acting opiate
prn, with dose large enough to relieve pain or cause side effects as bad as pain; add long-acting opiate if using short-acting
opioid regularly; oral opiates superior to IV, except for 10 to 20-min time to onset
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| IV and patient-controlled analgesia (PCA): advantages—better patient satisfaction; more convenient for staff;
self-administration allows for faster dose titration; make dose per injection large enough to provide relief; keep lockout
interval or dosing interval short enough to break pain crisis; write interval based on time to peak onset in acute setting
(safer than writing for larger dose; allows nurse to reassess pain in 30 min); basal rate/long-acting opioids—long-acting
opioids, eg, methadone not for acute pain; use for maintenance of analgesia; when calculating maintenance requirements
or thinking of basal rate, ignore loading dose necessary to break pain crisis; after patient comfortable, calculate
maintenance requirement by determining dose necessary to maintain comfort; for patients with acute incisional pain
without history of pain; standard mix 80% to 90% short-acting opiate and little-to-no long-acting opiate; patients with
cancer pain or chronic pain need 70% to 80% long-acting opiate
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| IV opioid choices: morphine—can produce itching, nausea, and confusion in elderly patients; hydromorphone
(Dilaudid)—consider using as standard IV agent in hospital instead of morphine (may produce less confusion or discharges
to rehabilitation hospitals for altered mental status postoperatively); speaker opines hydromorphone superior to
morphine (better side effect profile); pharmacokinetics roughly same as for morphine; fentanyl—fewer side effects; onset
too fast (cannot give large dose all at one time IV); good for use in PCA; drug of choice in ICU
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| Oral opioids: weak—speaker prefers hydrocodone with acetaminophen (Norco) and hydrocodone with ibuprofen (Vicoprofen);
most powerful opiates given without having to deal with schedule 2 restrictions; strong—avoid prescribing fentanyl
lollipops for chronic pain (patients rapidly develop tolerance)
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| Long-acting opioids: “contins” expensive, but calculating doses easy; consider fentanyl patch (less subject to diversion);
methadone—N-methyl-D-aspartate (NMDA) antagonist properties make it preferable for people with chronic pain;
methadone comes in IV and elixir forms; dose changes can take 2 to 3 days to take effect
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| Key points: break pain crisis early; more difficult to control pain longer patient suffers uncontrolled pain
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| Preemptive analgesia: epidurals, local anesthetics; NDMA antagonists, eg, ketamine, may be beneficial; opiates useless
because they induce hyperalgia; nonsteroidal anti-inflammatory drugs (NSAIDs) effective
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| Nonopioid adjuncts: consider NSAIDs (dramatically reduce opioid consumption; many side effects, including inhibition
of bone growth), local anesthestics, NMDA antagonists, acetaminophen (keep <4 g/day), cyclooxygenase (COX)-2
inhibitors (do not cause platelet inhibition); use aspirin in patient with coronary disease (NSAIDs and COX-2 inhibitors
both have thrombotic complications)
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Educational Objectives
| The goal of this activity is to provide a greater understanding of procedural sedation and pain management in the emergency
department and acute settings. After hearing and assimilating this program, the clinician will be better able to:
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| 1. Describe procedural sedation.
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| 2. Evaluate a patient prior to procedural sedation.
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| 3. List the advantages and disadvantages of pharmacologic agents used in procedural sedation.
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| 4. Describe the noninvasive methods for diagnosis of respiratory depression in patients taking opiates to control pain.
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| 5. Discuss the advantages and disadvantages of different intravenous (IV) and oral opioid agents used for pain reduction.
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Discussed on This Program
Acetaminophen (N -acetyl-P -aminophenol; APAP) [several trade names and formulations]
Aspirin (acetylsalicylic acid; ASA) [several trade names]
Atropine sulfate [AtroPen, Atropine Sulfate Ophthalmic, Atropine Care, Atropine-1, Atropisol, Isopto Atropine, Sal-
Tropine]
Etomidate [Amidate]
Fentanyl citrate [Sublimaze]
Flumazenil [Apotex, APP, Romazicon]
Glycopyrrolate [Robinul, Robinul Forte]
Hydrocodone bitartrate and acetaminophen [Norco, others]
Hydrocodone bitartrate and ibuprofen [Tiva, Vicoprofen]
Hydromorphone HCl [Dilaudid, Dilaudid-5, Dilaudid-HP, Palladone]
Ketamine HCl [Ketalar]
Methadone HCl [Dolophine HCl, Methadone HCl Diskets, Methadone HCl Intensol, Methadose]
Methohexital sodium [Brevital Sodium]
Midazolam HCl [Versed]
Morphine sulfate [Astramorph PF, Avinza, DepoDur, Duramorph, Infumorph, Infumorph 200, Infumorph 500, Kadian,
MSIR, MS Contin, Oramorph SR, RMS, Roxanol, Roxanol 100, Roxanol T]
Naloxone HCl [Narcan]
Pentobarbital sodium [Nembutal, Nembutal Sodium, Nembutal Sodium Solution]
Phenobarbital [Bellatal, Luminal Sodium, Solfoton]
Propofol [Diprivan]
Suggested Reading
American College of Emergency Physicians: Procedural sedation in the emergency department. Ann Emerg Med.
46:103, 2005; Asenjo JF et al: Opioids: other routes for use in recovery room. Curr Drug Targets. 6:773, 2005; Bahn
EL et al: Procedural sedation and analgesia: a review and new concepts. Emerg Med Clin North Am. 23:503, 2005;
Doyle L et al: Pediatric procedural sedation and analgesia. Pediatr Clin North Am. 53:279, 2006; Godwin SA et al:
American College of Emergency Physicians. Clinical policy: procedural sedation and analgesia in the emergency department.
Ann Emerg Med. 45:177, 2005; Green SM et al: Clinical practice guideline for emergency department ketamine
dissociative sedation in children. Ann Emerg Med. 44:460, 2004; Hansen GR: The drug-seeking patient in the emergency
room. Emerg Med Clin North Am. 23:349, 2005; Hansen GR: Management of chronic pain in the acute care setting.
Emerg Med Clin North Am. 23:307, 2005; Miller MA et al: Procedural sedation and analgesia in the emergency department:
what are the risks? Emerg Med Clin North Am. 23:551, 2005; Rupp T et al: Inadequate analgesia in emergency
medicine. Ann Emerg Med. 43:494, 2004; Sacchetti A et al: Emergency department procedural sedation formularies. Am
J Emerg Med. 23:569, 2005.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue is the faculty reports
nothing to disclose.
Dr. Torbati was recorded December 9, 2005, in West Hollywood, CA, at 3rd Annual Emergency Medicine Symposium,
sponsored by Cedars-Sinai Medical Center, Department of Emergency Medicine. Dr. Burkhardt was recorded October 24-
27, 2005, in San Francisco, CA, at Topics in Emergency Medicine, sponsored by the University of California, San Francisco,
School of Medicine. The Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the
production of this program.
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