Emergency Airway Management

THE AIRWAY COURSE EMERGENCY

General Session Workshop Simulation Skills Station Advanced Simulation Evaluation

THE EMERGENCY AIRWAY MANAGEMENT

1980RSI –whether to do it 1985RSI – how to do it 1990RSI –how to do it optimally 2000 RSI – on whom not to do it 2004 RSI -widespread, success high “ 이제 나가야 할 방향은 ?“

it’s that last 10% of cases..... where are we now :not an acceptable standard but the gold standard what devices and knowledge do we need to have to manage difficult and failed airways optimally ?

오늘의 목표 “ 준비가 되었습니까 ?“ “ 자신 있습니까 ?“

RAPID SEQUENCE INTUBATION (RSI) What Is RSI ? Where Does It Fit In ? Technique RSI Pharmacology

WHAT IS RSI ? (1) definition virtually simultaneous administration, after preoxygena- tion, of a potent sedative agent and a rapidly acting neuromuscular blocking agent to induce unconscious- ness and motor paralysis for tracheal intubation simultaneousfor tracheal intubationafter preoxygenation

WHAT IS RSI ? (2) definition assumes :patient has a full stomach :no interposed ventilation : preoxygenation : Sellick’s maneuver

WHAT IS RSI ? (3) ANESTHESIOLOGYEMERGENCY MEDICINE Rapid Sequence InductionRapid Sequence Intubation for operationfor life-saving always readynot ready patient status knownpatient status unknown cancellation possiblecancellation impossible

WHERE DOES IT FIT IN ? MAIN EMERGENCY AIRWAY MANAGEMENT ALGORITHM

The Difficult Airway (1) “the difficult airway is something one anticipates” “the failed airway is something one experiences” difficult airway management as high as 20% of all emergency intubations :intubation failure 0.5% to 2.5% :can’t intubate/can’t oxygenate 0.1% to 0.5%

The Difficult Airway (2) difficult BMV :MOANS difficult laryngoscopy and intubation :LEMON difficult cricothyrotomy :SHORT

difficult BMV : MOANS Mask Seal Obesity/Obstruction Age No Teeth Stiff bushy beards, crusted blood on the face, disruption of lower facial continuity BMI >26 kg/m2, third-trimester gestation, angioedema, Ludwig’s angina, upper airway abscesses, epiglottitis > 55 years old edentulous patient asthma, COPD, pulmonary edema, ARDS, advanced pneumonia

difficult laryngoscopy and intubation (1) : LEMON difficult laryngoscopy; benefit by using intubating stylet

difficult laryngoscopy and intubation (2) : LEMON best attempt 1)performance by a reasonably experienced endoscopist 2)no significant muscle tone 3)the use of the optimal sniff position 4)the use of external laryngeal manipulation (BURP) 5)length of blade 6)type of blade should an OTI attempt fail it seems reasonable to change something on the subsequent attempt to enhance the chances of success

difficult laryngoscopy and intubation (3) : LEMON Look Externally Evaluate Mallampati Score Obstruction Neck Mobility external evidence of lower facial disruption; MOANS; SHORT the first 3 assesses the adequacy of oral access; the second 3 addresses the capacity of the mandibular space; the final 2 identifies the location of the larynx in relation to the base of tongue tip of the mentum ~ hyoid bone hyoid bone ~ thyroid notch crude Mallampati measure by looking into the supine, obtunded patient’s mouth with a tongue blade and light muffled voice (hot potato voice) difficulty swallowing secretions (d/t pain or obstruction) stridor (ominous sign) C-spine immobilization in trauma, ankylosing spondylitis, RA

difficult cricothyrotomy : SHORT Surgery (or other airway disruption) Hematoma (includes infection/abscess) Obesity (includes any access problem) Radiation Distortion (and other deformity) Tumor

TECHNIQUE The Seven Ps of RSI Preparation Preoxygenation Pretreatment Paralysis with induction Protection with positioning Placement with proof Postintubation management the sequence : the time of administration of Sch is ZERO

preparation ZERO minus 10 min assessed for difficulty of intubation fallback plans for failed intubation cardiac monitoring, BP monitoring, pulse oximetry sequence of pharmacologic agents drawn up possible CIx to any agents reviewed all equipment tested throughout this preparatory phase, the patient should be receiving preoxygenation care and time taken during this preparation and assessment phase pay great dividends when the sequence is initiated

preoxygenation (1) ZERO minus 5 min oxygen reservoir within the lungs and body tissue :100% oxygen for 3 min :8 vital capacity breaths while receiving 100%oxygen

preoxygenation (2) how long is apnea time ? : 전공의가 자신을 100% O 2 로 preoxygenation 후 Sch 을 IV 로 자가 주입, SpO 2 가 언제 90% 이하로 떨어질까요 ? A)60~90 sec B)91~180 sec C)181~360 sec D)>360 sec

preoxygenation (3) which patient fully preoxygenated desaturates the most ? A)normal, healthy 47 years old, 70kg, male B)60 years old, 80kg male, moderate COPD C)14 months old toddler D)22 years old, 55kg female, intoxicated

preoxygenation (4) the time to desaturate from 90% to 0% is dramatically less than the time to desaturate from 100% to 90%

pretreatment ZERO minus 3 min LOAD

paralysis with induction ZERO a rapidly acting induction agent given in a dose adequate to produce prompt LOC immediately followed by the N-M blocking agent, usually Sch both are given by IV push rapid loss of consciousness rapid N-M blockade brief period of apnea

protection and positioning (1) ZERO plus 20~30 sec Sellick’s maneuver :initiated immediately on the observation that the patient is losing consciousness :maintained throughout the entire intubation sequence until the ETT has been correctly placed, the position verified, and the cuff inflated 30 Newton

protection and positioning (2) before placing the laryngoscope into the patient’s mouth, the sniffing position is created by placing a pillow, folded towel, or sheet under the patient’s head to facilitate extension of the head on the neck and slight forward flexion of the lower C-spine on the chest

placement and proof (1) ZERO plus 45 sec the patient’s jaw should be tested for flaccidity and intubation undertaken end-tidal CO 2 detection is mandatory Sellick’s maneuver then discontinued on the order of the intubator

placement and proof (2) correct placement of tracheal tube (1) primary confirmation by P/Ex direct visualization listen and observe 5-point auscultation laryngoscopic view moisture condensation

placement and proof (2) correct placement of tracheal tube (2) secondary confirmation qualitative end-tidal CO 2 detector purple (poor) → yellow (yes) 2~5% EtCO 2 = 15~38 mmHg Pco 2 at least 6 ventilations cardiac arrest capnography 4.5~6% EtCo 2 = 35~45 mmHg Pco 2 esophageal detector device the aspiration bulb technique the aspiration syringe technique

the “standard care” is to perform both primary and secondary confirmation techniques sequencing differences are virtually the only contemporary areas of debate and disagreement whenever there is doubt about the results from primary or secondary confirmation, the best course of action is to remove the tracheal tube and provide BMV

placement and proof (4) BURP Backward, Upward, Rightward Pressure

placement and proof (5)

postintubation management (1) ZERO plus 1 min ETT taped or tied in place mechanical ventilation chest radiograph :assess pulmonary status and ensure that mainstem intubation has not occurred hypotension

postintubation management (2) long-term sedation and paralysis :lorazepam 0.03 to 0.05 mg/kg :pancuronium 0.1 mg/kg or vecuronium 0.1 mg/kg opioid analgesic :morphine 0.1 to 0.2 mg/kg or fentanyl 1~2 mcg/kg

RSI PHARMACOLOGY Pretreatment Agents Sedative And Induction Agents Neuromuscular Blocking Agents Depolarizing (Noncompetitive) NMBA Nondepolarizing (Competetive) NMBAs

Pretreatment Agents general approach the LOAD approach

general approach (1) the CNS response :↑ cerebral metabolic oxygen demand :↑ cerebral blood flow : ↑ ICP

general approach (2) the cardiovascular system response (sympathetic nervous system) :in children, vagal stimulation of the SA node :in adults, stimulation of the cardioaccelerator nerves and sympathetic ganglia - NE release, epinephrine release, renin-angiotensin system activation bradycardia ↑ HR ↑ BP

general approach (3) the respiratory system response :activation of the upper-airway reflexes -laryngospasm and coughing :actuation of the lower-airway reflexes -increase in airway resistance (bronchospasm)

the LOAD approach lidocaine (xylocaine) opioid - fentanyl (sublimaze) atropine defasciculating agents

lidocaine (xylocaine) 1.5 mg/kg IV elevated ICPreactive airways disease caution : seizures

opioid - fentanyl (sublimaze) IICPintracranial hemorrhage ischemic heart diseasecerebral or aortic aneurysm aortic dissectionpenetrating trauma 3 mcg/kg over 30 to 60 sec caution : respiratory depression : hypotension : rigidity

atropine children <10 years old 0.02 mg/kg IV

defasciculating agents IICP are a concern and Sch selected as the muscle relaxant rocuronium 0.06 mg/kg IV vecuronium 0.01 mg/kg IV caution : muscular weakness : apnea

Summary pretreatment agents are used to attenuate the adverse physiologic responses to laryngoscopy and intubation should be administered 3 minutes before induction to match peak drug effect with airway manipulation LOAD (lidocaine, opioids, atropine, defasciculating agents) LIDOCAINE (xylocaine) : 1.5 mg/kg IV 3 minutes before airway manipulation : IICP, bronchospastic disease (asthma, COPD, cardiac asthma) OPIOID fentanyl (sublimaze) : 3 mcg/kg IV 3 minutes before induction : IICP, ischemic heart disease, aneurysm or dissection, hemodynamically stable penetrating vascular trauma ATROPINE : 0.02 mg/kg IV 3 minutes before induction : any child less than 10 years of age undergoing RSI with Sch DEFASCICULATION : vecuronium, pancuronium, or rocuronium at 10% of the normal paralyzing dose 3 minutes before induction : IICP who will be receiving Sch

Sedative And Induction Agents ultra-short-acting barbiturates thiopental sodium (pentothal) benzodiazepines miscellaneous agents etomidate (amidate) ketamine (ketalar) propofol (diprivan)

ultra-short-acting barbiturates thiopental sodium (pentothal)

thiopental sodium (pentothal) (1) induction dose (mg/kg)3-6 onset (sec)<30 t 1/2 α (min)2-4 duration (min)5-10 t 1/2 β (hr)10-12

thiopental sodium (pentothal) (2) : indications and contraindications Ix : IICP or status epilepticus absolute CIx : acute intermittent porphyria relative CIx : reactive airways disease

thiopental sodium (pentothal) (3) : dosage and clinical use potent venodilator and myocardial depressant :dose must be decreased in patients with decreased intravascular volume, compromised myocardial function, and the elderly (1 to 2 mg/kg IV) avoided entirely in frankly hypotensive patients

thiopental sodium (pentothal) (4) : adverse effects central respiratory depression venodilation myocardial depression dose-related release of histamine

benzodiazepines midazolamlorazepamdiazepam induction dose (mg/kg) a a onset (sec) t 1/2 α (min) duration (min) t 1/2 β (hr) a not recommended for use as an induction agent for emergency RSI

miscellaneous agents etomidate (amidate) ketamine (ketalar) propofol (diprivan

etomidate (amidate) (1) induction dose (mg/kg)0.3 onset (sec)15-45 t 1/2 α (min)2-4 duration (min)3-12 t 1/2 β (hr)2-5

etomidate (amidate) (2) : indications and contraindications induction agent of choice for most emergent RSIs because of its rapid onset, its profound hemodynamic stability, its positive CNS profile, and its rapid recovery no contraindications to its use not FDA approved for use in children

etomidate (amidate) (3) : dosage and clinical use in compromised patients, the induction dose should be reduced commensurate with the patient’s clinical status

etomidate (amidate) (4) : adverse effects myoclonic movement during induction is common and has been confused for seizures :no clinical consequence and generally terminates promptly as the N-M blocking agent takes effect decrease both serum cortisol and aldosterone levels (reversible blockade of 11-beta-hydroxylase) :more common with continuous infusions

ketamine (ketalar) (1) induction dose (mg/kg)1-2 onset (sec)45-60 t 1/2 α (min)11-17 duration (min)10-20 t 1/2 β (hr)2-3

ketamine (ketalar) (2) : clinical pharmacology releases catecholamines, stimulates the sympathetic nervous system, and therefore augments HR and BP directly stimulates the CNS, increasing cerebral metabolism, cerebral metabolic oxygen demand (CMRO 2 ), and CBF, thus potentially increasing ICP :corresponding increases in MAP may offset the rise in ICP directly relaxes bronchial smooth muscle, producing bonchodilatation

ketamine (ketalar) (3) : indications and contraindications induction agent of choice : reactive airways disease : hypovolemic or hypotensive without serious brain injury in normotensive or hypertensive patients with ischemic heart disease, catecholamine release may adversely increase myocardial oxygen demand

propofol (diprivan) (1) induction dose (mg/kg)1.5-3 onset (sec)15-45 t 1/2 α (min)2-4 duration (min)5-10 t 1/2 β (hr)1-3

propofol (diprivan) (2) : clinical pharmacology direct reduction in BP through vasodilatation and direct myocardial depression, resulting in a decrease in cerebral perfusion pressure :rarely, if ever, the induction agent of choice in emergenct RSI, where patient instability is the norm

propofol (diprivan) (3) : indications and contraindications excellent induction agent in a very stable patient no absolute contraindications

propofol (diprivan) (4) : dosage and clinical use because of its predictable tendency to reduce MAP, smaller doses are generally used

Neuromuscular Blocking Agents depolarizing (noncompetitive) NMBA nondepolarizing (competetive) NMBAs

depolarizing (noncompetitive) N-M blocking agent : Sch (anectine) clinical pharmacology indications and contraindications dosage and clinical use adverse effects

clinical pharmacology (1) Sch is two molecules of Ach linked back-to-back over an ester bridge stimulates all of the nicotinic and muscarinic cholinergic receptors of the sympathetic and parasympathetic nervous system :cardiac muscarinic receptors stimulation causes bradycardia, especially in children :negative inotrope but no clinical relevance :releases histamine but no clinical significancy

clinical pharmacology (2) Ach-Ach Ach AchR fasciculations paralysis pseudocholinesterase acetylcholinesterase

indications and contraindications Sch remains the NMBA of choice for emergency RSI absolute contraindications :a personal or family Hx of malignant hyperthermia :at risk for Sch-related hyperkalemia relative contraindications :can’t intubate, can’t oxygenate/ventilate situations

dosage and clinical use (1) in the normal-sized adult patient, the recommended dose of Sch for emergency RSI is 1.5 to 2 mg/kg IV (3 to 4 mg/kg IM) the margin of safety in dosing Sch is up to 6 mg/kg

dosage and clinical use (2) in obese patients pseudocholinesterase activity increases linearly with increasing weight as does the size of the ECF compartment :increase doses of Sch in children <10 years of age, length-based dosing is recommended :the recommended dose is 2 mg/kg IV :in the newborn (<12 months of age) the appropriate dose is 3 mg/kg IV

dosage and clinical use (3) because children have higher vagal tone than adults, atropine 0.02 mg/kg IV should be pretreated this same vagotonic effect must be anticipated in adults when repeated doses of Sch are administered :succinylmonocholine, the initial metabolite of Sch, sensitizes the cardiac muscarinic receptors in the SA node to repeat doses of Sch :atropine should be readily at hand

adverse effects fasciculations hyperkalemia bradycardia prolonged N-M blockade malignant hyperthermia trismus/masseter muscle spasm

fasciculations occur simultaneously with increases in ICP, IOP, and intragastric pressure :only the increase in ICP is clinically important fasciculations inhibited by defasciculating dose (10% of the normal paralyzing dose) of a nondepolarizing NMBA :0.01 mg/kg of vecuronium or pancuronium, or 0.06 mg/kg of rocuronium

hyperkalemia (1) serum K + increases minimally (0 to 0.5 mEq/L) when Sch is administerd :rhabdomyolysis and receptor upregulation rhabdomyolysis :often associated with myopathies :resuscitation less successful than in receptor up- regulation because of less physiologic reserve

hyperkalemia (2) receptor upregulation (1) mature receptors mature receptors mature receptors immature receptors receptor upregulation burnsdenervation crush injuries intraabdominal infections myopathiesrenal failure immature receptors immature receptors immature receptors immature receptors immature receptors immature receptors immature receptors immature receptors 4- to 5-day period

immature receptors prolonged channel opening (4 times longer than mature receptors) increasing levels of K +

bradycardia most commonly in children because of their heightened vagotonic state :bradycardia is attenuated or abolished by administering atropine 0.02 mg/kg IV as a pretreatment drug in adults, repeated doses of Sch may produce the same vagotonic effects and administration of atropine may become necessary

prolonged N-M blockade reduced concentrations of pseudocholinesterase :liver disease, pregnancy, burns, oral contraceptives, metoclopramide, bambuterol, or esmolol a 20% reduction in normal levels will increase apnea time about 3 to 9 minutes

malignant hyperthermia (1) a personal or family Hx of malignant hyperthermia is an absolute CIx to the use of Sch triggered by halogenated anesthetics, Sch, vigorous exercise, and even emotional stress acute loss of intracellular Ca 2+ control :muscular rigidity, autonomic instability, hypoxia, hypotension, severe lactic acidosis, hyperkalemia, myoglobinemia, and DIC

malignant hyperthermia (2) elevations in temperature are a late manifestation masseter spasm has been claimed to be the hallmark :Sch can promote isolated masseter spasm :alone is not pathognomonic treatment consists of discontinuing the known or suspected precipitant and the immediate administration of dantrolene sodium (dantrium) :initial dose 2.5 mg/kg IV repeated every 5 minutes (maximum dose 10 mg/kg)

trismus/masseter muscle spasm if masseter spasm interferes with intubation, a full paralyzing dose of a competitive nondepolarizing agent should be administered serious consideration should be given to the Dx of malignant hyperthermia

nondepolarizing (competitive) N-M blocking agents clinical pharmacology indications and contraindications dosage and clinical use

clinical pharmacology benzylisoquinolinum compounds (atracurium and mivacurium) aminosteroid compounds (vecuronium, pancuronium, and rocuronium)

AchR Ach nondepolarizing NMBAs Ach acetylcholinesterase

indications and contraindications pretreatment agents to attenuate increases in ICP attributed to muscle fasciculations muscle relaxant of choice if Sch is contraindicated or unavailable maintain postintubation paralysis no known CIx

dosage and clinical use (1) pancuroniumvecuroniumrocuronium intubating dose (mg/kg) pretreatment (mg/kg) onset (sec) duration (min) full recovery (hr)

dosage and clinical use (2) for defasciculation when Sch is used in patients with elevated ICP :10% of the paralyzing dose of any of the nondepolarizing agents (pancuronium 0.01 mg/kg, vecuronium 0.01 mg/kg, rocuronium 0.06 mg/kg) for RSI when Sch is contraindicated or not available :the drug of choice is rocuronium 1.0 mg/kg IV based on its time to onset

dosage and clinical use (3) for postintubation management when continued N-M blockade is desired :vecuronium 0.1 mg/kg IV or pancuronium 0.1 mg/kg IV is appropriate

dosage and clinical use (3)

RSI SEQUENCE

CASE 1 45 세 남자, 내원 10 분 전 병원 행사장에서 떡 많이 먹기 대회에서 대회 참가자가 떡을 먹다가 갑자기 호흡곤란 호소하면서 응급진료센터로 내원 universal choking sign unable to breathe unable to phonate complete obstruction of the airway

management of complete obstruction by a foreign body convert an obstructing tracheal foreign body to an obstructing mainstem bronchial foreign body (which can be removed in the OR)

CASE 2 30 세 남자, 내원 15 분전 MVC 로 내원 V/SBP 140/80 mmHg, PR 120 bpm, RR 16/min SpO 2 93% in room air PEx M/S stupor scalp laceration otherwise no remarkable findings approximate body weight 100 kg

difficult airway assessment (1) MOANS assesses potential for difficult mask ventilation Mask seal Obese (BMI >26 kg/m 2 ) Aged (>55 yo) No teeth Stiff (asthma, COPD, ARDS, term pregnancy)

difficult airway assessment (2) LEMON assesses potential for difficult airway Look at head + neck Evaluate Mallampati Obstruction Neck mobility

difficult airway assessment (3) SHORT assesses potential for difficult cricothyrotomy previos Surgery Hematoma or infection Obese Radiation Tumor

RSI sequence for patients with elevated ICP 150 mg 1 mg 300 mcg 30 mg 150 mg thiopental 300 mg

CASE 3 30 세 여자, 내원 15 분전 MVC 로 내원 V/SBP 70/50 mmHg, PR 135 bpm, RR 8/min SpO 2 80% in room air PEx M/S stupor scalp laceration otherwise no remarkable findings approximate body weight 50 kg

CASE 4 30 세 여자, 내원 30 분전부터의 호흡곤란으로 119 통해 응급진료센터 내원 8 년 전부터 bronchial asthma 로 medication 중 V/S BP 150/90 mmHg, PR 130 bpm, RR 24/min SpO 2 82% in room air PExexpiratory wheezing on whole lung fields approximate body weight50 kg

first-line therapy (1) :definitely effective ▪ start with oxygen at 4 L/min ▪ β 2 -agonists (nebulized albuterol) mg every 20 minutes for 3 doses -in periarrest, 5-mg doses every 20-min x mL diluted in 2 to 2.5 mL N/S

first-line therapy (2) :probably effective (1) ▪ corticosteroids -methylprednisolone 125 mg IV (2 mg/kg) every 6 h -hydrocortisone 5 to 7 mg/kg IV every 4-6 h -dexamethasone 0.25 mg/kg IV every 8-12 h

first-line therapy (2) :probably effective (2) ▪ anticholinergics (ipratropium bromide) -mix 0.5 mg in 2.5 mL N/S ▪ magnesium sulfate -2 to 3 g IV at rates of 200 mg/min to 1 g/min

first-line therapy (3) :possibly effective (1) ▪ epinephrine -total dose is 0.01 mg/kg divided into 3 doses given at time zero, 20 minutes, and 40 minutes ▪ terbutaline mg SQ, repeat once in min

first-line therapy (3) :possibly effective (2) ▪ methylxanthines (aminophylline IV) -loading dose 5 mg/kg over 30 to 45 min - infusion 0.5 to 0.7 mg/kg/h

CASE 5 65 세 남자 내원 2 시간전부터의 mental change 로 내원 5 일전 발생한 Rt. MCA infarct 으로 한방병원에서 입원 중 상기 증세로 전원 V/S BP 160/100 mmHg, PR 110 bpm, BT 38.6 ℃ SpO 2 89% in room air M/S deep drowsy

absolute CIx to Sch Hx of malignant hyperthermia burns >5 days ~ until healed muscle damage (crush) >5 days ~ 6 months SCI, stroke (denervation, UMN, LMN) >5 days ~ 6 months N-M disease, myopathies indefinitely as long as disease is active intra-abdominal sepsis >5 days ~ resolution of infection