Procedural Sedation and Analgesia

Aka: Procedural Sedation and Analgesia, Procedural Sedation, Procedural Anesthesia, Conscious Sedation, Sedation, Deep Sedation, PSAA

1. See Also
   1. Labor Sedation
   2. Local Skin Anesthesia
   3. Regional Anesthesia (Nerve Block)
   4. Emergency Procedure
   5. Trauma in Pregnancy
2. Definitions
   1. Procedural Sedation and Analgesia (PSAA)
      1. Replaces the term Conscious Sedation
   2. Minimal Sedation
      1. Anxiolysis
      2. Normal response to verbal stimuli
      3. No Ventilatory depression
      4. No cardiovascular depression
   3. Moderate Sedation
      1. Depressed Level of Consciousness
      2. Purposeful response to verbal commands or light stimulation
      3. No Ventilatory depression
      4. No cardiovascular depression
   4. Deep Sedation
      1. Depressed Level of Consciousness
      2. Response only to repeated or painful stimuli
      3. Ventilatory depression may occur
      4. No cardiovascular depression
   5. General Anesthesia
      1. Depressed Level of Consciousness
      2. No arrousable
      3. Airway and Ventilatory support required
      4. Cardiovascular depression may occur
   6. Dissociative Sedation
      1. Trance state (cataleptic) induced by Ketamine
      2. Potent Analgesic and amnestic properties
      3. Maintains airway reflexes and spontaneous respirations
      4. Cardiovascular function maintained
3. Indications
   1. Adult precedural Sedation
      1. Fracture or dislocation reduction
      2. Significant Wound Debridement
      3. Rectal foreign body
      4. Ketamine is usually preferred in children
   2. Child Procedural Sedation
      1. Fracture or dislocation reduction
      2. Laceration Repair or Wound Debridement
      3. Abscess Incision and Drainage
      4. Imaging studies
      5. Ear Foreign Body
      6. Entrapment of penis in zipper
4. Contraindications
   1. Significant or unstable cormorbid illness
5. History
   1. Last oral intake
   2. Medications
   3. Medication Allergies
   4. Serious medical conditions (affecting major organ systems)
      1. See ASA Physical Status Classification System
      2. Cerebrovascular Disease
      3. Coronary Artery Disease, Congestive Heart Failure or arrhythmia
      4. Obstructive Sleep Apnea, COPD or Asthma
      5. Chronic Kidney Disease
      6. Diabetes Mellitus
6. Exam: Airway
   1. Lemon Mnemonic
   2. Mallampati Score
7. Preparation: Fasting
   1. Fasting is preferred but not required prior to procedure
   2. Food intake is not absolute contraindication
      1. Aspiration is less likely with Fasting
      2. Urgent procedures may be performed without Fasting
   3. Formal guidelines for elective procedures (per anesthesia)
      1. No clear liquids in last 2 hours
      2. No Breast Milk in 4 hours (or infant formula in 6 hours)
      3. No food, milk, solids in last 6 hours
   4. Consider risk factors for aspiration
      1. Advanced age
      2. Comorbid medical conditions
      3. Gastroesophageal Reflux risks (e.g. Hiatal Hernia, Bowel Obstruction, ileus, Peptic Ulcer Disease)
   5. No evidence to support prophylaxis
      1. No evidence for pre-procedural Antacids, H2 Blockers or Anticholinergics
   6. Emergency department guidelines for NPO prior to Procedural Sedation
      1. Evidence does not support the same NPO guidelines in Emergency Department as for elective procedures
      2. ACEP guidelines note that recent food intake is not a contraindication to Procedural Sedation
         1. Godwin (2014) Ann Emerg Med 63(2): 247-58 +PMID:24438649 [PubMed]
      3. NPO duration prior to Procedural Sedation does not appear to impact risk of Vomiting or aspiration
         1. Molina (2010) Int J Evid Based Healthc 8(2): 75-8 [PubMed]
         2. Bell (2007) Emerg Med Australas 19(5): 405-10 [PubMed]
8. Preparation: Emergency Preparedness
   1. Requires provider experienced in Sedation
      1. Knowledgeable about sedatives and monitoring
      2. Skilled in ABC Management
      3. Assign one person (e.g. clinician, RN, RT, anesthesia) to monitor and manage anesthesia and respiratory status
         1. Capnography (End-Tidal CO2) may be adequate for monitoring (without additional required staff)
         2. However, many organizations require one trained practitioner dedicated to monitoring anesthesia
   2. Monitoring during procedure
      1. Continuous waveform End-Tidal CO2 Monitoring (Capnography)
         1. Commonly used for emergency department Procedural Sedation
            1. Not required per ACEP guidelines as of 2014
         2. Significantly increases early detection of repiratory depression and apnea
            1. Decreased Hypoxia risk by 10-20%
            2. Alerts to apnea 4-8 minutes before Oxygen Saturation changes
            3. Supplemental Oxygen delays oxygen desaturation during apnea
            4. Deitch (2010) Ann Emerg Med 55(3): 258-64 [PubMed]
         3. May not alter outcomes compared with standard monitoring
            1. van Loon (2014) Anesth Analg 119(1): 49-55 [PubMed]
         4. Available as part of a Nasal Cannula type device
         5. Technique for attaching to face mask
            1. Insert a 14 gauge angiocatheter through holes in face mask outflow
            2. Attach 14 gauge catheter to Capnography
      2. Cardiac monitoring
      3. Pulse Oximetry
         1. Not useful for timely diagnosis of apnea if Supplemental Oxygen used
         2. Identifying apnea during Sedation may be delayed as much as 4 minutes using Oxygen Saturation alone
         3. Use end tidal CO2 for patients on Supplemental Oxygen
   3. Emergency equipment
      1. Oxygen Delivery
         1. Apply Supplemental Oxygen to all patients undergoing Procedural Sedation
         2. Consider High Flow Oxygen for Apneic Oxygenation
      2. Airway Suction equipment
      3. Nasopharyngeal Airway (Nasal Trumpet)
      4. Bag-valve mask
         1. Administer a few breaths initially to assure that patients may be supported with with bag-valve mask
         2. Be ready for airway collapse (e.g. Sleep Apnea patient with a large Tongue)
            1. Jaw Thrust alone can significantly open the airway
            2. Assistant may be required to perform Jaw Thrust, while a second provider provides bag-valve-mask
            3. Consider inserting 2 Nasal Airways (and an Oral Airway may be inserted if no Gag Reflex)
      5. Intubation equipment
      6. Resuscitation cart
      7. Reversal agents
         1. Naloxone
         2. Flumazenil
            1. Only use if not on chronic Benzodiazepines (risk of acute withdrawal and Status Epilepticus)
9. Preparation: Resource Limited Environments (e.g. low and middle income countries)
   1. See Resource Limited Environment
   2. Consider alternatives to Conscious Sedation
      1. Defer non-emergent procedures to the most appropriate available local options
      2. Local or Regional Anesthesia is preferred
      3. Consider non-intravenous options as listed below
   3. Preparation
      1. Familiarize yourself with locally available medications
      2. Follow a pre-procedure checklist
      3. Prepare the evironment
         1. Adequate lighting
         2. Clean, organized work area
         3. Disrobe patient for adequate access
      4. Alert all staff to remain vigilant throughout procedure
         1. Assign one person dedicated solely to monitoring during the procedure
      5. Obtain IV Access
         1. Run crystalloid (NS or LR)
         2. Consider initial 500 cc or 10-20 cc/kg bolus
      6. Monitoring equipment as available
      7. Emergency airway and breathing equipment prepared and ready for use (ideally as above)
   4. Airway Monitoring
      1. Maintain airway with Jaw Thrust
      2. Monitor for airway obstruction
      3. Nasopharyngeal Airway, suction and intubation equipment should be ready
   5. Breathing monitoring
      1. Pulse Oximeter (preferred if available)
         1. If not available, continuously auscultate Respiratory Rate, volume, rhythm and observe chest rise
      2. Supplemental Oxygen
         1. If not available, use bag-valve mask to improve oxygenation by preventing Atelectasis
   6. Circulation monitoring
      1. Obtain Blood Pressure every 5 minutes
      2. Continuous Pulse Oximetry
         1. If not available, palpate pulse or auscultate heart sounds continuously
   7. References
      1. Acker, Koval and Leeper (2017) Crit Dec Emerg Med 31(4): 3-13
10. Preparation: BiPAP
    1. Indications
       1. Sleep Apnea patient with risk of airway compromise during procedure
       2. Elderly
    2. Starting setting
       1. Inspiratory pressure: 10 cm H2O
       2. Expiratory pressure: 5 cm H2O
11. Protocol: Two phase Approach (Hennepin protocol, per Jim Miner, MD)
    1. Obtain adequate analgesia with Opioids 20 minutes prior to Procedural Sedation
    2. Administer Procedural Sedation (e.g. Propofol) without analgesia (e.g. Fentanyl)
    3. Analgesia persists through procedure, while not complicating respiratory status
12. Protocol: Difficult IV Access options
    1. Intranasal medications
       1. Fentanyl
       2. Midazolam (Versed)
       3. Lidocaine
       4. Dexmedetomidine (Precedex)
    2. Intramuscular Medications
       1. Ketamine
       2. Midazolam (Versed)
       3. Hydromorphone (Dilaudid)
    3. Rectal Medications
       1. Methohexital (Brevital)
       2. Diazepam (Valium)
       3. Midazolam (Versed)
13. Precautions
    1. Monitor patient response (grimace, whimper, withdrawal from pain) to procedure
       1. Maintain awareness of inadequate anesthesia and analgesia, in addition to standard monitoring
    2. Pregnancy
       1. See Trauma in Pregnancy
14. Preparations: Sedatives
    1. Ketamine
       1. Indications
          1. Preferred sedative in children
          2. Sedation in a patient with a potentially difficult airway
          3. Sedation in critically ill patient (where Hypotension risk with Propofol)
          4. ASA Physical Status Score 2 and 3
       2. Effects
          1. Analgesic and anesthetic properties
       3. IV
          1. Onset in 1 min, dissociation for 15 min, and recovery over 60 min
          2. Initial
             1. Adult: 1.0 mg/kg slow IV over 1-2 min
             2. Child: 1.5 mg/kg slow IV over 1-2 min
          3. Next
             1. Administer 1/2 of intial dose every 10 minutes as needed
       4. IM
          1. Onset in 3-5 min, dissociation for 15-30 min, and recovery over 90-150 min
          2. Initial: 4-5 mg/kg IM (adult and child)
          3. Repeat 4-5 mg/kg IM after 10 min for one dose if needed
       5. Adverse effects
          1. Least adverse effects in children of the procedural sedatives
             1. Bhatt (2017) Pediatr 171(10): 957-64 +PMID:28828486 [PubMed]
          2. Laryngospasm (0.3 to 0.4% of cases, especially children)
             1. See Laryngospasm on Induction
             2. See Laryngospasm Notch Maneuver
             3. Typically transient, but risk of airway obstruction
          3. Risk of emergence reaction (e.g. agitation)
             1. Consider concurrent Midazolam in adults (0.03 mg/kg) to counter emergence reaction
             2. Sener (2011) Ann Emerg Med 57(2):109-114 [PubMed]
          4. Older data recommends avoiding in Closed Head Injury (risk of Increased Intracranial Pressure)
             1. Newer data suggests safe in Head Injury
          5. Hypersalivation
             1. Anticholinergics (Atropine, glycopyrrolate) are not recommended to dry secretions
             2. Green (2009) Ann Emerg Med 54(2): 171-80 +PMID:19501426 [PubMed]
          6. Respiratory drive is typically preserved
             1. However, transient apnea (10-20 s) may occur with rapid infusion
             2. Infuse Ketamine slowly (over 1-2 minutes)
    2. Propofol
       1. Indications
          1. Preferred procedural sedative in adults for brief procedures
          2. Indicated for ASA Physical Status Score 2 (non-hypotensive, stable)
             1. Use Ketamine or Etomidate instead in patients at risk of Hypotension
       2. Adverse Effects
          1. Hypotension
          2. Respiratory depression
          3. Appears safe in pregnancy and Lactation (limited data)
       3. Effects
          1. Propofol is primarily anesthetic
          2. Administer concurrent Analgesics (e.g Fentanyl 50 mcg increments)
       4. Intravenous
          1. Adult
             1. Initial: 1 mg/kg IV over 20-30 seconds (typically given as smaller increments)
                1. Obese patients: Consider 0.7 to 0.8 mg/kg for starting dose
                2. Thin young patients: Consider 1.5 mg/kg for starting dose (risk of respiratory depression)
             2. Frail elderly patients: Consider 20-30 mg IV for starting dose
             3. Next: 0.5 mg/kg IV as needed
             4. Next: 0.25 to 0.5 mg/kg IV every 3 minutes
             5. Decrease dose in older patients (cummulative required total dose decreases with age)
                1. Age 18-40 years old: 2 mg/kg total dose
                2. Age 41-64 years old: 1.7 mg/kg total dose
                3. Age >64 years old: 1.2 mg/kg total dose
                4. Patanwala (2013) J Emerg Med 44(4): 823-8 +PMID:23333181 [PubMed]
          2. Child
             1. Initial: 1 mg/kg IV (up to 40 mg) over 20-30 seconds (typically given as smaller increments)
             2. Next: 0.5 mg/kg IV (up to 20 mg) as needed
          3. Typically no respiratory depression at 1 mg/kg dose
             1. Amnesia occurs at this dose
             2. However, apnea may occur when Propofol is combined with Opioids
          4. Perform painful procedures immediately following infusion
             1. Amnestic effect wears off prior to Sedation
    3. Etomidate
       1. Indications
          1. Indicated for ASA Physical Status Score 2 and 3
          2. Consider for Sedation in hypotensive adult patient (or Ketamine)
             1. Otherwise Propofol is preferred adult sedative due to greater efficacy and less Myoclonus than Etomidate
             2. Miner (2007) Ann Emerg Med 49(1): 15-22 [PubMed]
       2. Adverse Effects
          1. Myoclonus (20-40% of cases)
             1. Administer Etomidate slowly over 90 seconds
             2. Pretreatment
                1. Fentanyl (or Alfentanil or Sufentanil)
                2. Alternatively, Magnesium Sulfate or Midazolam may be used as pretreatment
          2. Adrenal suppression
             1. Adrenal suppression is typically associated with continuous infusion
             2. Appears safe for single dose
             3. Avoid in Sepsis
          3. Respiratory depression (10% of cases)
          4. Nausea and Vomiting (at emergence)
          5. Seizure threshold lowered (avoid in Seizure disorder)
       3. Pharmacokinetics
          1. Onset: <1 minute
          2. Duration: 5-15 minutes
       4. Dosing: IV
          1. Initial: 0.1 to 0.2 mg/kg IV
          2. Repeat 0.05 mg/kg IV every 3-5 minutes as needed
    4. Pentobarbital
       1. Indicated in brief Sedation
          1. Ideal for CT Head (brief action, Seizure Prophylaxis)
          2. May be accompanied to CT with RN (low risk of respiratory depression, or other serious adverse effects)
       2. Observe for Hypotension
       3. Dose: 2.5 mg/kg IV (may repeat additional 1.25 mg/kg as needed twice)
    5. Methohexital (Brevital)
       1. Indications
          1. Propofol is preferred over Methohexital
          2. Consider methohexital where unable to obtain Intravenous Access (can be given rectally)
          3. Safe in pregnancy
       2. Pharmacokinetics
          1. Barbiturate with rapid onset of action, and with IV dosing same as IM dosing
          2. Onset within 30-60 minutes
          3. Duration 3-5 minutes
       3. Adverse Effects
          1. Cardiopulmonary depression
             1. Follow same precautions as for Propofol
          2. Respiratory depression (10-22%)
          3. Hypotension (1-3%)
          4. Paradoxically lowers Seizure threshold (avoid in Seizure disorder)
             1. Contrast to other barbiturates which are used to a abort Seizures
          5. Laryngospasm
             1. Give a full dose (additional Methohexital) to fully supersaturate GABA receptors
             2. Otherwise similar management to Ketamine laryngospasm
             3. See Laryngospasm on Induction
          6. Other adverse effects
             1. Vomiting
             2. Cough
             3. Hiccups
    6. Ketaphol (Ketamine with Propofol)
       1. Postulated to reduce risk of Hypotension and apnea of Propofol by cutting dose with Ketamine
          1. Initial studies recommended ratio of 4:1 Propofol to Ketamine for adequate effect
          2. Some protocols start 1:1 ratio Propofol to Ketamine 0.5 then add Propofol to effect
       2. Most studies show no significant benefit over Propofol alone (similar efficacy and safety)
          1. Andolfatto (2012) Ann Emerg Med 59(6): 504-12 [PubMed]
          2. Nejati (2011) Acad Emerg Med 18(8): 800 [PubMed]
          3. Ferguson (2016) Ann Emerg Med 86(5): 574-82 [PubMed]
       3. Typical protocol
          1. Start: Administer mix of Propofol 0.5 mg/kg AND Ketamine 0.5 mg/kg
          2. Next: Administer additional Propofol 0.5 mg/kg every 90 seconds as needed to adequate effect
    7. Midazolam (Versed)
       1. Indications
          1. Other Sedation agents are preferred in most cases
          2. Intranasal Versed in children may allow for imaging, Intravenous Access, Laceration Repair
       2. Intravenous (onset 2-3 min and lasts 45-60 min)
          1. Age 6 months to 5 years
             1. Initial: 0.05 to 0.1 mg/kg IV
             2. Titrate: Up to 1 mg increments IV every 3 min to max of 0.6 mg/kg
          2. Age 6 to 12 years
             1. Initial: 0.025 to 0.05 mg/kg IV
             2. Titrate: Up to 1 mg increments IV every 3 min to max of 0.4 mg/kg
          3. Adults (and over age 12 years)
             1. Initial: 0.02 mg/kg IV (1-2 mg IV)
             2. Titrate: 1 mg increments IV every 3 min
       3. IM (onset 10-20 min and lasts 60-120 min)
          1. Child: 0.1 to 0.15 mg/kg
          2. Adult: 0.07 mg/kg up to 5mg
       4. Other routes
          1. Oral: 0.5 mg/kg
          2. Nasal: 0.2 to 0.5 mg/kg intranasal (1/2 in each nostril) using 5 mg/ml up to 10 mg
          3. Rectal 0.25 to 0.5 mg/kg per Rectum
       5. Contraindicated in pregnancy (Category D), and wait at least 4 hours for Breast Feeding
       6. Commonly used in combination with Fentanyl
          1. When combined with Opioids (e.g. Fentanyl), use lower Midazolam dose
          2. Risk of Deep Sedation with cardiopulmonary depression
       7. Unpredictable at increased doses (risk of respiratory and cardiovascular depression)
          1. Unreliable Sedation for painful procedures
          2. Best delivered in incremental doses (e.g. 1 mg increments)
          3. Exercise extra caution in elderly, debilitated, children, hepatic insufficiency, Dementia
       8. Reversal: Flumazenil 0.01 mg/kg up to 2 mg over 15 seconds
          1. Do not use if on longterm Benzodiazepines
15. Preparations: Analgesics
    1. Fentanyl
       1. Nasal: 2 mcg/kg intranasal (1/2 in each nostril)
       2. Nebulized: 4 mcg/kg in breath activated neb
          1. As effective as IV Morphine using ultrasonic nebulizer with tight fitting mask
          2. Farahmand (2014) Am J Emerg Med 32(9):1011-5 +PMID:25027194 [PubMed]
       3. IV (onset in 1-3 min, lasting 30-60 min)
          1. Adult: 50 mcg/dose every 3 minutes, titrating to effect
          2. Child: 1 mcg/kg/dose IV every 3 minutes, titrating to effect
             1. Age 1-3 years old: 2-3 mcg/kg/dose every 30-60 minutes as needed
             2. Age 3-12 years old: 1-2 mcg/kg/dose every 30-60 minutes as needed
             3. Age >12 years old: 0.5-1 mcg/kg/dose every 30-60 minutes as needed
       4. Reversal: Naloxone
       5. Adverse effects
          1. Less histamine release than with Morphine
          2. Respiratory depression
             1. Supplemental Oxygen, Jaw Thrust maneuver, bag-valve mask
             2. Use lower doses in combination with Midazolam (Versed)
    2. Morphine
       1. IV/IM/SC: 0.05 to 0.2 mg/kg every 2-4 hours up to 15 mg (typically given in 2-4 mg increments)
       2. Intramuscular onset of activity may be delayed as long as 30 minutes
       3. Adverse Effects
          1. Nausea or Vomiting
             1. Consider pretreatment with Antiemetic (e.g. Ondansetron)
          2. Hypotension
             1. Consider pretreatment bolus of crystalloid (500 cc or 10-20 cc/kg NS)
          3. Pruritus and/or rash
             1. Typically not Allergic Reaction
             2. Morphine may result in histamine release
       4. Reversal: Naloxone
    3. Oxycodone (immediate release)
       1. Oral route (better than IM opiods, without significant delay)
          1. Adults (and over age 12 years) 5-10 mg every 4-6 hours as needed
          2. Child: 0.05 to 0.3 mg/kg/dose (up to 10 mg) every 4-6 hours as needed
       2. Reversal: Naloxone
    4. Hydrocodone-Acetaminophen (Vicodin or Lortab) 2.5 mg/5 ml elixir
       1. Oral: 0.2 mg/kg (up to 1.25 mg if under age 2 years, and up to 5 mg if age 2-12 years)
       2. Reversal: Naloxone
    5. Ketorolac (Toradol)
       1. IV/IM: 0.5 mg/kg (up to 30 mg)
    6. Nitrous Oxide
       1. Mixed with 40% oxygen (pre-set)
       2. Dose is self administered by patient breathing through demand valve mask
       3. Onset within 5 minutes and duration <5 minutes after discontinuing
       4. Activity is similar to Opioids
       5. Consider for IV Access start
16. Preparations: Older agents to avoid (replaced by other agents above)
    1. Chloral Hydrate
       1. Older oral Sedation agent similar to Ethanol with GABA-receptor mediated effects
       2. Rapidly metabolized to the active form, trichloroethanol
       3. Agitation and Nausea are common
       4. Common use among pediatric dentists (with case reports of outpatient pediatric deaths)
       5. Ketamine or oral/intranasal Midazolam are far preferred over oral Chloral Hydrate
17. Management: Disposition
    1. Continue monitoring until no risk of respiratory depression
    2. Observe for at least 2 hours if any reversal agent used (e.g. Naloxone, Flumazenil)
    3. Discharge after patient is alert and back to baseline mental status
    4. Give Discharge Instructions
       1. Family or friend should observe the patient for several hours after discharge
       2. Patients may expect Nausea, Fatigue or light headedness for up to 24 hours after discharge
18. References
    1. Acker, Koval and Leeper (2017) Crit Dec Emerg Med 31(4): 3-13
    2. Braude in Herbert (2013) EM:Rap 13(11): 14
    3. Kay (2015) Crit Dec Emerg Med 29(8): 11-17
    4. Lester and Braude in Herbert (2014) EM:Rap 14(5): 5-6
    5. Weingart in Majoewsky (2012) EM:RAP 12(2): 8
    6. Miner (2012) APLS Lecture, HCMC, Minneapolis
    7. Hamilton (2012) Tarascon Pharmacopeia, Jones and Bartlett, Burlington
    8. Rispoli (2002) Tarascon Pocket Orthopedics, Loma Linda, p. 115
    9. Singh in Blaivas (2012) Emergency Medicine - an International Perspective, p. 199-208
    10. Strayer in Herbert (2017) EM:Rap 17(12): 17-9
    11. University Minnesota Childrens - Pediatric Emergency Drug Card
    12. Becker (2012) Anesth Prog 59:28-42 [PubMed]
    13. Brown (2005) Am Fam Physician 71:85-90 [PubMed]
    14. Godwin (2014) Ann Emerg Med 63(2): 247-58 [PubMed]