Advanced Sedation Fellows’ Conference 9-26-07 Thao M. Nguyen, MD PEM fellow Emory University Children’s Healthcare of Atlanta Objectives Review historical perspective of pain & sedation Review presedation factors Review common agents of procedural sedation Review more restricted or up-and-coming agents Review common complications of sedation 2 Historical perspective Pain in children are underreported, undertreated, and misunderstood Children do not get the same treatment as adults who have similar painful conditions 3 Misconceptions Children…. • cannot experience pain due to a immature CNS • have no memory of pain • cannot quantify or qualify their pain (thereby pain underestimated) Physicians… • are concerned about masking symptoms • fear adverse effects cardio-pulmonary decompensation addiction • lack sedation training 4 Development Milestones 5 < 6 mo reflect parent’s anxiety, withdraw from pain, grimace, cry 6-18 mo increase anxiety, fear pain, withdraw 18-24 mo anxious, express pain – “ouch” 3 years localize pain and identify cause visually; environment and distraction are very important 5-7 years understand pain, localize pain, more able to cooperate The old way 6 The new way 7 Sedation Goals Alleviate anxiety Minimize pain Minimize negative psychological impact Maximize amnesia Control behavior to expedite efficiency and improve quality Maintain safety and minimize risks Ensure safe discharge BETTER OUTCOME 8 Definitions Sedation occurs along a continuum… Analgesia • Relief of pain Minimal Sedation (anxiolysis) • Responds to verbal commands • Cognitive function and coordination may be impaired • Ventilatory and cardiovascular not affected 9 Definitions Moderate • Responds to verbal commands alone or accompanied by touch. Airway, ventilation and cardiovascular maintained Deep • Cannot be easily aroused but responds to noxious stimuli. May require assistance to maintain airway and adequate ventilation, cardiovascular maintained General Anesthesia • Patient cannot be aroused. Often requires assistance to maintain airway and positive pressure ventilation. Cardiovascular status may be impaired 10 Presedation Factors Factors relating to procedure: • Duration of the procedure • Pain as a side effect of a procedure • Position required for the procedure • Anxiety/Stress/inability to cooperate as a side effect of the procedure • Availability of rescue resources Factors relating to patient: • Discussed in further slides Factors relating to provider: • Dedicated sedation monitor • Skills related to depth of sedation • Back-up systems and ability to rescue 11 ASA Physical Status Classification 12 Class Physical status I Healthy patient II Mild systemic disease, no functional limitation III Severe systemic disease that limits activity IV Incapacitating systemic disease that is a constant treat to life V Moribund not expected to survive 24 hrs without an operation add E to any of above for emergent procedure ASA examples • Class I • Class II Unremarkable PMHx Mild asthma, controlled SZ, controlled diabetes, anemia • Class III Moderate to severe asthma, pneumonia, moderate obesity, uncontrolled SZ or DM • Class IV Severe BPD, advanced degrees of pulmonary, cardiac, hepatic, renal, or endocrine insufficiency • Class V Septic shock, severe trauma 13 ASA I and II are usually appropriate candidates ASA III cases should be individually considered ASA IV and V, consult anesthesia or ICU Presedation evaluation History Allergies Meds Past History – prior sedation/anesthesia Last meal Events Exam Airway--Mallampati Heart Lungs Other 14 Mallampati Class I: soft palate, OP, uvula, pillars Class II: soft palate, OP, portion of uvula Class III: soft palate, base of uvula Class IV: hard palate only 15 Fasting ASA Guidelines • 2 hours clears • 4 hours breast milk • 6 hours light meal • 8 full stomach ACEP • “recent food intake is not a contraindication for administering procedural sedation and analgesia, but should be considered in choosing the timing and target level of sedation” 16 Informed Consent Make sure you have discussed it with the parents, signed and in the chart We have a CHOA sedation video in English and Spanish 17 Preparations Expect and be prepared for the worse You should have the skills to rescue from one level higher than anticipate SOAPS Suction Oxygen Airway equipment BVM, blades, ETT Pharmacy Appropriate meds, reversal agents, emergency drugs Special monitors 18 MSMAID Monitor CR monitor (EKG, HR, RR), BP, continuous pulse ox, capnography Suction Medicine / Machine Airway equipment IV access Drugs for rescue (includes O2) Be familiar… Route Mechanism of action How metabolized Adverse reactions Time to onset/offset • Avoid dose stacking • Avoid multiple drugs 19 Common Agents Chloral Hydrate Benzodiazepines • Midazolam • Diazepam Barbiturates • Pentobarbital • Thiopental • Methohexital Opiates • Morphine • Fentanyl Ketamine 20 chloral hydrate Unknown mechanism of action Contraindicated in hepatic or renal disease May have paradoxical excitement Side Effects: • Hypotension • Cardiopulmonary depression • GI upset 21 Dose: 25-100 mg/kg PO/PR • Max 1 gram in infants 2 grams in children Onset: 30-60min Duration 4-9 hours 30 hrs in neonate midazolam (Versed®) Shortest acting benzodiazepine PO The most commonly used sedation • Dose: 0.5-1 mg/kg, max 20mg agent in children and adults • Onset: 15 min Provides potent sedation, • Duration: 30-90 min anxiolysis, and amnesia Intranasal or Sublingual No analgesia • Dose: 0.2-0.5 mg/kg, max 10 mg May be given IV, PO, IN, IM, PR • Onset: 10-15 minutes Bitter aftertaste so mix in Syrpalta • Duration: 60 minutes Burns in nose IV Contraindicated with narrow angle • Dose: 0.05-0.1mg/kg, max glaucoma and shock 0.6mg/kg or 10mg • Onset: 2-3 min • Duration: 60-90 min 22 pentobarbital barbiturates drug of choice for head trauma, status epilepticus Side effects: • Hypotension • Myocardial depression • Respiratory depression • Bronchospasm- stimulate histamine release Contraindications: • liver failure • CHF • hypotension NO analgesia! 23 Dose: • 2-6 mg/kg/dose PO/PR/IM • 1-3 mg/kg/dose IV • Max dose is 150mg Onset: 15-60 min Duration: 1-4 hours morphine Opioid Slower onset, longer duration Better for procedures that have a longer duration ( ≥ 30 minutes) Histamine release can cause flushing and itching Side effects Respiratory Depression Hypotension Bradycardia Nausea Urticaria 24 Dose: 0.1-0.2 mg/kg IV/IM/SQ, max 10-15 mg bolus, no ceiling Onset: 5-10 minutes Peak effect: 15-30 minutes IV 30-60 minutes IM ½ life = 2-9 hours (neonates) Duration: 2-4 hours fentanyl Synthetic opioid Excellent choice for pain management & sedation with short duration 75-200 times more potent with much shorter half-life than MSO4 Rapid onset, elimination, and lack of histamine release; metabolize in liver chest wall rigidity syndrome associated with doses > 15 mcg/kg and rapid infusion; reverse with naloxone and/or paralytics Respiratory depression may last longer than the period of analgesia 25 Dose is 1-2 mcg/kg over 3-5 minutes Titrate to effect every 3-5 minutes Onset: 1-2 minutes Peak effect: 10 minutes Duration: 30-60 minutes Reversal Agents Naloxone • Competitive opiate antagonist • 0.1 mg/kg IV/IM/SC/ET (min 0.1 mg & max 2 mg) Q2-3 minutes until response; may repeat Q2-3 min • ½ life = 1-2 hr • 30 minute duration; monitor for re-sedation • Reverses resp depression, sedation, and analgesia • Rebound sedation and apnea may occur Flumazenil • 0.01mg/kg IV (max 0.2 mg) then 0.005-0.01 mg/kg Q1 min to total max dose 1 mg. May repeat doses in 20 min, max 3 mg in 1hr • Do not use in kids on chronic benzo due to seizure risk If a reversal agent is required the patient must be observed for an additional 2 hours from the time the reversal agent is given 26 ketamine Provides both analgesia and sedation Releases endogenous catecholamines • Preserves respiratory drive and airway protective reflexes • Bronchodilator effect (good for asthmatics) • Maintains hemodynamic stability Rapid infusion causes respiratory depression and apnea 27 Dose: 1-3 mg/kg IV 3-5mg/kg IM Onset: 1 minute IV 5 minute IM Duration: • 60 min for sedation • 40 to 45 min for analgesia ketamine COMPLICATIONS • Laryngospasm (1%) • Hypersalivation • Apnea • Vomiting • Agitation/Hallucinations/Emergence Reactions Older aged population • Hypertension • Increased Intracranial and Intraocular Pressure • Myoclonus 28 Less common agents Propofol Ketofol Brevital Etomidate Dexmedetomidine Nitrous oxide 29 propofol (Diprivan®) Diprivan 30 propofol Ultra short acting sedative No analgesic Dose dependent level of sedation with rapid recovery time (high lipid solubility) Common adverse effects: cardiopulmonary depression, upper airway obstruction, hypoventilation and apnea leading to hypoxemia Attending needs to be present during the entire infusion! 31 Dose: • 1-3 mg/kg IV • Repeat 0.5mg/kg Q2-3 min Onset: 40 secs Duration: 1-3 mins Contraindicated in patients with egg or soybean allergy. IV site pain: 1% lidocaine propofol Lidocaine 1% 1 cc in PIV (use with tourniquet) 1 minute prior to propofol INDUCTION • Draw up 3-5 mg/kg • Give 1-1.5 mg/kg initially over 30-60 secs, then increments of 0.5 mg/kg • Babies < 6mos or pts with CNS pathology usually require higher dose (at least 5 mg/kg) • Bigger kids start @ 1 mg/kg then 0.5 mg/kg INFUSION • Infusion 5 mg/kg/hr, titrate by 1-2 mg/kg/hr increments, max 18 Concurrent opioid therapy can be associated with an increased risk of respiratory depression and hypotension 32 Why is propofol so restricted in the pediatric population, especially in the PICU settings? 33 propofol infusion syndrome 1992, report of 5 children with croup or bronchiolitis in an ICU, sedated with propofol and subsequently died of metabolic acidosis and myocardial failure - Bray - 1998, 18 critically ill pediatric pts experienced bradycardia, asystole, severe metabolic acidosis, lipemia, hepatomegaly and rhabdomyolysis - CMAJ 2001 2001 FDA noted of higher death rates in PICU pts given propofol for sedation in a randomized controlled trial. - Medwatch 2001 34 propofol infusion syndrome Cornfield & Tegtmeyer “Continuous Propofol Infusion in 142 Critically Ill Children” Retrospective review of a case series 18 mo period; PICU & BMT; age 2 mo – 18 yo Propofol infusion < 50 mcg/kg/min = 3 mg/kg/h • Additional bolus of 1 mg/kg Q1h RESULTS • Median infusion 16.5 hrs; longest < 20 hrs • Adequate sedation (no extubation or CVL dislodgement) • Not assoc with metabolic acidosis or hemodynamic compromise • Conclusion: continuous infusion of propofol for extended periods of time should not exceed 67 mcg/kg/min = 4 mg/kg/h Pediatrics 2002;110(6):1177-1181 35 propofol infusion syndrome Described in critically ill children given long term propofol infusion Severe metabolic acidosis and rhabdomyolysis associated with hepatomegaly, lipemia, myocardial failure and hyperkalemia Relative absence in adults Not associated with brief procedural sedation Limited use to the physicians on the sedation team 36 ketofol 1:1 mixture of ketamine 10 mg/ml and propofol 10 mg/ml In theory, the opposing hemodynamic & respiratory effects of each drug might be complementary and minimize overall adverse effects Prospective study of 114 procedural sedation and analgesia events for orthopedic procedures; effective & safe; fast recoveries (median 15 minutes) - Willman 2007 37 +++ --- Ketamine Analgesia Amnesia Little respiratory/ CV depression Vomiting Laryngospasm Propofol Reliable sedation Amnestic Anti-emetic Respiratory & CV depression Bradycardia No analgesia Dose: 1-3 mg/kg IV slow push, usually 1-1.5 mg/kg Onset: < 1 min Duration: 15-20 min methohexital (Brevital®) Rapid, ultra short-acting barbiturate anesthetic Indication similar to propofol and with egg or soy allergies; $$$ Contraindicated in porphyria, temporal seizures Rapid infusion can lead to transient hypotension & tachycardia; respiratory depression/apnea Associated with hiccups, coughing, muscle twitching & rigidity, salivation, emergence delirium Metabolism in the liver 38 Dose: • IV 1-2 mg/kg induction of 1%; 3 mg/kg/hr infusion, titrate by 1.5 • IM 6.6-10 mg/kg of 5% sol’n • PR 25 mg/kg, 10%, max 500 mg Contraindicated in pts < 1 mo Onset: 30 secs IV 2-10 mins IM 5-15 mins PR Duration: 5-10 mins IV etomidate 39 Ultra short acting sedative-hypnotic Unknown mechanism of action Rapid IV induction Minimal respiratory depression or hemodynamic instability No histamine release Myocardial & cerebral protection No analgesia Adverse Reactions • Nausea and vomiting – 5% • Local burning infusion pain • Myoclonic movements • Inhibits steroid synthesis Contraindications: • Seizure disorder • Children < 2 y/o Dose: 0.2-0.5 mg/kg IV Induction 0.3 mg/kg IV over 30-60 sec Duration: 5-10 min Full recovery in 30 min Re-dose with 0.1mg/kg every 5-10 minutes as needed Lidocaine 1% for iv site pain etomidate 40 Synthesized in 1964 1972 clinical practice in Europe 1983 approved for use in the US; promoted as a safe agent for continuous sedation in mechanically ventilated pts. • Trend toward increased mortality reported in critically ill, multitrauma pts receiving continuous infusion etomidate in the ICU; 25% vs 44% - Ledingham and Watt • Retrospective review of 428 multi-trauma pts from 1969-1982 increased mortality 28% vs 47%; p< 0.05 More pronounced with ↑ MV duration and means of sedation (benzos 28% vs 77% etomidate; p< 0.0005) All showed at least one subnormal level of serum cortisol Long-term use of etomidate fell into disfavor Package insert for etomidate: “this formulation is not intended for administration by prolonged infusion.” etomidate Adrenal suppression Single induction dose • ↓ cortisol & aldosterone levels (30 mins) • transient < 24 hrs Inhibits conversion of cholesterol to cortisol by a reversible & concentrationdependent blockade of 11ß-hydroxylase >> 17α-hydroxylase 41 etomidate controversy Ideal first-line induction agent for select ED pts requiring RSI intubation; stability and predictability Etomidate single use in septic shock • Adrenal insufficiency is transient and clinically not relevant VS • Etomidate should be abandoned altogether in the ICU increased the risk of adrenal insufficiency by 12X; transient effect prolonged in critically ill pts; poor prognosis associated with adrenal insufficiency in critical illness - Annane 2005 Meta-analyses support the use of low-dose steroid replacement among pressor dependent septic shock pts 42 etomidate controversy 3 approaches to the use of etomidate in septic shock pts: • eliminate etomidate use altogether in this subgroup Ketamine? • use a lower dose of etomidate in conjunction with lower doses of other induction agents • routinely administer concomitant corticosteroids with etomidate Annane study showed 94% (68/72) were nonresponders to high-dose cosyntropin stimulation test Mortality cost of adrenal suppression by etomidate offset by corticosteroid administration 43 dexmedetomidine (Precedex®) Relatively selective α2adrenoceptor agonist with sedative properties preserves cardiorespiratory function maintained RR & oxygenation less concurrent opiate use not approved in children adverse effects • hypotension • bradycardia 44 Dose: infusion 1 mcg/kg over 10 min infusion 0.4 mcg/kg/h (0.2-0.7) Onset: 6 mins t½ : 2 hrs nitrous oxide 45 sweet smelling inorganic gas by Priestly in 1772 late 1800s dental procedures analgesic & sedative properties • 20% N2O = morphine rapid onset and recovery • 30-80% N2O LOC suitable for use when short acting analgesia/sedation required for brief procedures adverse reactions: • CNS depression • Cardiorespiratory depression • Exacerbate existing airway obstruction • Worsened existing pneumothorax • Megaloblastic anemia affects vitamin B12 metabolism nitrous oxide 2 large prospective studies • 0.35% (27 of 7679 children) major adverse events O2 desats, airway obstruction, apnea, bradycardia, oversedation • All resolved within minutes of discontinuation • Higher adverse event in pts < 1 yo (2.3%) and received additional psychotropic drugs • 5% minor adverse events: euphoria, nausea, vomiting, dizziness, parasthesia - Pena 1999 - Gall 2001 46 nitrous oxide Entonox • fixed concentration of 50% N2O / 50% O2 • self-administered via a demand valve system with a weighted mask • oversedation less likely; young children cannot use The Matrix Quantiflex nitrous oxide delivery system • Variable delivery of N2O (0-70%) with oxygen administered via a constant gas flow system that does not require patient effort to trigger • oversedation & respiratory depression more likely • Need constant monitor 47 Common Problems Inadequate sedation • Assessment/reassessment • Evaluation of efficacy and duration • Timely intervention Excessive sedation/narcosis • Special circumstances (shock, airway, CNS and concurrent medications) Most common causes of death • Hypoxemia • Airway obstruction • Cardiovascular collapse (myocardial depression, vasodilation, bradycardia, hypotension, arrhythmias) 48 Hypoxemia Is the airway patent? • Upper airway obstruction common, especially in patients predisposed to obstructive sleep apnea (preexisting obstruction, macroglossia, micrognathia, etc) • Don’t merely give additional oxygen, but evaluate for obstruction, and intervene as needed… 49 Sniffing position 50 Hypoxemia (cont’d) If airway is clear, is patient breathing? • Yes, but shallow/infrequent Stimulate to breathe Support with BVM, intubate if prolonged support needed (or unstable airway) Consider reversal agent (if available for choice of sedative) • No As above, but don’t waste time attempting stimulation or reversal – provide PPV 51 BVM 52 Hypotension Treatment based on tachy/bradycardia, perfusion, sedative Usually due to excessive sedation with myocardial insufficiency (esp. with opiates) and/or vasodilation (esp. barbiturates, opiates, benzos) • Verify/obtain patent airway, assist ventilation, intubate if needed, give 100% O2 • Fluid bolus 10-20 cc/kg rapidly • Chest compressions if bradycardia or PEA • Discontinue sedation (esp. if using continuous infusion) • Consider reversal agent, atropine, epinephrine 53 Post-sedation If reversal agent administered, patient must be observed for at least 2 hours after last reversal dose Discharge criteria • Airway patent and stable vital signs • Easy arousability • Ability to talk • Ability to sit up unaided • Well hydrated • Taking po • Patient/home care provider able to understand written instructions • Patient has safe transportation home (patient may NOT drive self home) 54 Conclusions Sedation occurs along a continuum Most serious adverse effects can be avoided by appropriate patient and drug selection and assessment • When in doubt, obtain anesthesiology consult Anticipate potential problems, and be prepared to intervene PPV by BVM more important than sedation reversal Titrate, titrate, titrate… Evaluate, evaluate, evaluate… 55 Citations Annane D. ICU physicians should abandon the use of etomidate! Intensive Care Med 2005;31:325-6 Bray RJ. Propofol infusion syndrome in children. Paediatr Anaesth. 1998;8:491-9 Chang P, Warren D et al. Use of propofol sedation in the pediatric emergency department. Paediatrics & Child Health. 2003;8 FDA issues warning on propofol. CMAJ 2001;164(11):1608 Gall O. Adverse events of premixed nitrous oxide & oxygen for procedural sedation in children. Lancet. 2001;358:1-2 Hom J. Pediatics, Sedation. emedicine.com. Last updated January 29, 2007 Kraus & Green. Sedation and analgesia for procedures in children. NEJM. 2000.342:939 Jackson WL. Should we use etomidate as an induction agent for endotracheal intubation in patients with septic shock? A critical appraisal. Chest. 2005;127:1031-8 Morris C. Etomidate for emergency anaesthesia mad, bad and dangerous to know? [editorial]. Anaesthesia. 2005;60:737-40 Murray H. Etomidate for endotracheal intubation in sepsis. Acknowledging the good while accepting the bad. Chest. 2005;127:1031-8 Pena BM. Adverse events of procedural sedation & analgesia in a PED. Ann Emerg Med. 1999;34:483-91 Willman EV. A Prospective Evaluation of “Ketofol” (Ketamine/Propofol combination) for Procedural Sedation and Analgesia in the Emergency Department. Annals EM. 2007; 49(1):23-30. Wooltorton E. Propofol: contraindicated for sedation of pediatric intensive care patients. CMAJ. 2002;167(5) Zed PJ. Etomidate for rapid sequence intubation in the emergency department: is adrenal suppression a concern? CJEM. 2006;8(5):347-50 56