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Advanced Emergency Airway Management Core Rounds July 22, 2004 Rob Hall MD, PGY5 FRCPC Emergency Medicine Arun Abbi MD, FRCPC Outline • Some basics and motherhood statements • An approach to emergency airway management • Minimal literature review • Procedures are not the focus • Case examples – – – – Approach Focus on difficult airways Selected Controversies Pediatric airway mx Case • picture MVC vs Trailer, two reds, one needs intubation How do you prepare? Intubation = flight: preflight, flight, post-flight Pilot picture APPROACH TO THE AIRWAY Think of an intubation like a pilot flying a plane! Consider the following approach to ED airway management. PREFLIGHT FLIGHT POST-FLIGHT Prep equipment (SOLESD) Preoxygenate Think of 4 back ups!!!! Back up equipment nearby Tube 'em Danno Check placement CXR Sedation +/- paralysis Tx hypotension, hypoxia Part of being prepared is knowing your equipment Know your equipment Pre-oxgenation is an important step in preparation for intubation • Desat curve APPROACH TO THE AIRWAY Does the patient need to be intubated? ABCDEs Quckly evaluate the situation and the patient? What type of airway? CRASH AIRWAY EASY AIRWAY DIFFICULT AIRWAY Cardiac arrest Apneic Near death Not a crash airway No anticipated difficulty Difficult anatomy Difficult pathology Cases • 2yo drowning, PEA arrest – What type of airway? – Any drugs? • 77yo female, MVC, as you are assessing, GCS drops, BP 60 palp, HR 40, teeth a bit clenched – What type of airway? – Any drugs? THE CRASH AIRWAY JUST DO IT! Direct laryngoscopy with no drugs Unsuccessful TIME (can bag, sats ok) NO TIME (can't bag, sats dropping) Repeat attempts (up to 3) Add succinylcholine prn Go to failed airway algorithm Go to failed airway algorithm Case: Motorbike vs Car • 45yo male, Motorbike vs car • Hemodynamically stable: BP 175/50, HR 70, face ok • GCS 6 (E1V1M4) • Bilateral decorticate posturing • Anatomy looks normal • What type of airway? • What drugs would you use? THE “EASY” AIRWAY RAPID SEQUENCE INTUBATION Prepare, preoxy, pretreat, induction, paralysis, pass the tube, check placement Unsuccessful TIME (can bag, sats ok) NO TIME (can't bag, sats dropping) Repeat attempts (up to 3) Go to failed airway algorithm Go to failed airway algorithm Case: Motorbike vs Car • Pretreatment – Lidocaine – Fentanyl – ? Defasiculator • Induction – Etomodate or Pentothal • Paralytic – Succ • How does lidocaine work? • What is the evidence for lidocaine? • When should we use lidocaine? • Why use fentanyl here? • Is there any role for defasiculation? Lidocaine Pretreatment • How does it work? Blocks the direct reflex which increases ICP – Laryngoscopy ------------ increased ICP via direct reflex from laryngoscopy stimulation “Local” anesthetic Effect which decreases The response to laryngoscopy – Laryngoscopy ------------- sympathetic release which increases MAP and ICP – May also decrease brain’s oxygen utilization Lidocaine Pretreatment • How does it work? “Local” anesthetic effect which decreases the airway response to laryngoscopy – Laryngoscopy ------------ stimulation of “airway reflexes” which increases bronchoconstriction +/- secretions Lidocaine pretreatment: what is the evidence? • Evidence for “tight heads” – Vallancourt C. CJEM. Mar 2002. 4(2). – Systematic review of lidocaine and ICP – 348 studies, 25 RCTs included – Only one paper regarding intubation – 3 papers regarding tracheal suctioning – 24 papers looking at MAP changes with lidocaine Lidocaine Pretreatment • Vallancourt C. CJEM. Mar 2002. 4(2) – Bedford 1980 looked at intubations • N=20, elective brain tumor surgery • Lidocaine 1.5 mg/kg decreased ICP rise with intubation by 12 mmHg vs placebo – 3 Suctioning papers: decr ICP by 5 mmHg – 24 MAP papers: decrease MAP by average of 7 mmHg with lidocaine 1-3 mg/kg Lidocaine Pretreatment • Summary – – – – CPP = MAP – ICP Lidocaine decrease MAP and ICP What happens to CPP is unknown Neurologic outcomes not studied • Take home points – We really don’t know if lidocaine is effective – Most people currently are using lidocaine for head injuries and some are using in asthma/copd – Don’t waste time with lidocaine if the patient needs rapid airway control Case: Motorbike vs car; head trauma, normotensive • Why fentanyl pretreatment? • Is there any role for defasciculation? • What is the induction agent of choice for hypotensive, head injured patients? Fentanyl Pretreatment • When is it indicated? – Elevated ICP – Anyone where you don’t want and increase in HR and BP (cerebral aneurysm or AVM, aortic dissection, active ischemic heart dz, penetrating vascular injury) • What is the evidence? – Many studies documenting the blunting of sympathetic response to laryngoscopy and intubation but no outcome studies Pretreatment: defasiculation • What? 1/10 the intubation dose of rocuronium, vecuronium, pancuronium • Why? – Prevents fasciculations from increasing your ICP and intraocular pressure • Is this necessary? – Debatable: no evidence for – Reasons why NOT to do this • Adds another step, another drug • May cause apnea, paralysis at wrong time Pretreatment Medications Summary MED INDICATIONS L Lidocaine Tight heads Tight lungs O Opiate Tight heads Anyone where you don’t want incr HR/BP (Ao dissection, MI, SAH, etc) A Atropine Kids < 10 yo (some say 6yo) Second dose of succinylcholine F Fluids Hypotension Anyone where you expect decr BP D Defasiculator Tight heads (controversial) Tight eyes (controversial) Induction agents in hypotensive + head injured • Midazolam: NO • Propofol: NO • Ketamine – Debatable: likely will increase MAP and ICP – Most think ketamine is contraindicated with high ICP (limited evidence) • Pentothal: generally NO, could use at ½ the dose (1-2 mg/kg vs 3-5 mg/kg) • Etomodate – Drug of choice – Decrease the dose from 0.3 to 0.15 mg/kg Case: Addy is sick • 40 yo female • Known Addison’s • Abdo pain + hypovolemic + septic + ARDS • BP 85/50, HR 130 • Anatomy easy • What type of airway? • What drugs? • ? Etomidate for induction • You give etomidate and she has a seizure, why? Etomidate: will become the drug of choice for RSI! • Hemodynamically stable – Average decrease in SBP is 10% – Average decrease in SBP is 20% if already hypotensive – CAN DROP YOUR BP!!: decrease dose from 0.3 mg/kg to 0.15 mg/kg if concerned re hypotension • Decreases ICP • Very rapid onset (20-30sec): some give after succ Etomidate • Side-effects – N/V at emergence in 30% – Adrenal suppression: decreases serum cortisol, only reported with ICU infusions, never reported after single ED dose – Myoclonus • • • • ? Brain stem disinhibition Commonly mistaken for seizure 30% incidence quoted (? Reporting bias) Treat with benzo if prolonged/severe Etomidate • Contraindications –P –P –P –P Pregnant Pediatrics < 10 yo Prior seizures Poor adrenal function Case: globe rupture • On the exam, maybe! • 30yo female • In real life, NO! • Facial smash – IOP increases 5-10 mmHg with succ • Suspect globe – IOP increases 10-15 mmHg with blinking rupture – Think what rough intubation will do! • Is – Airway control more important – What to do? succinylcholine • Defasiculation can prevent increase contraindicated? in IOP with succ • Rocuronium is an option Contraindications to Succ • Absolute – Airway skills lacking – Allergy – Burn > 48hrs – Crush > 48hrs – CNS dz > 48hrs – CRF with hyperkalemia – Malignant hyperthermia – Myopathies • Relative – Pseudocholinesterase deficiency – Organophosphate toxic – Foreign body in airway – Cardiac tamponade – Globe rupture (debatable) – Abdo sepsis > 1 week Succ and hyperkalemia • Study of normal patients – – – – • • • • 46% with K+ increase 46% with K+ decrease 8% with no change Max change was 1 mEq/L Myopathies are the worst! Don’t forget about rhabdomyolysis If in doubt, use rocuronium Arrest after succ, think hyperkalemia Case: Aspirator • • • • 75yo female CVA 3 months ago Dysphagic Aspiration, resp failure, BP 150/70 • Anatomy easy • Easy airway approach • Can’t use succinylcholine • What is the timing principle? Timing Principle • If you are using rocuronium as the paralytic, it has a longer time to action (1-2 min) than the induction agent – Give rocuronium – Wait 30 – 45 seconds – Give etomidate – Wait 30 seconds – Intubate Case: I hate myself. • • • • • 25yo female Benzo, Etoh overdose GCS 8, BP 120/70, anatomy easy Type of airway? Do you need to add an induction agent to your RSI? Is an induction agent necessary if you are paralyzing a patient? • Controversial, no absolute right/wrong • Advantages of adding full induction – Improved patient comfort and decreased recall – Blunts rise in ICP, HR, BP, airway resistance – Decreases time to ideal intubation conditions • Peak effect of succ doesn’t occur until 3 min (despite onset at 45 sec) when given alone • You don’t want the pt to be apneic for 3 minutes and you don’t want to bag in between unless you have to • Several studies documenting that IDEAL INTUBATION CONDITIONS are present 45-60 seconds after induction agent + succinylcholine Case: Pneumonia, oops! • 80yo female • Resp failure from pneumonia, Pmhx hypertension and seizures • HR 110, BP 110/30, easy anatomy • What type of airway? • What drugs? • After intubation her BP is 80/40, HR 110 – What is the ddx? – Why hypotensive? – What is the treatment? Post-intubation Hypotension • Tension pneumo, Myocardial ischemia, Acidosis, high intrathoracic pressures are all on the differential dx • Volume depletion – Common in anyone with respiratory or critical illness that necessitates intubation • Sympathetic tone – Anyone that is critically ill has a maximal sympathetic output; deep induction takes away the stimulus ----------- end result is that they drop their pressure – Treat with fluids, pressors (be prepared!) Case: head to pavement • 3 yo male • Fall off deck, head to pavement • GCS 5 • Bagged by EMS • RSI by you • After intubation, patient desaturates and is difficult to bag. AE equal. – Why? – Differential? – Management? Post intubation Hypoxia • • • • • D O P E G Dislodged tube (must r/o) Obstructed tube Pneumothorax Equipment failure (wall to pt) Gastric distension more common in kid, ++ gastric distension leads to compression of the lungs Case: I can’t breath • • • • 16yo female Hx asthma Sudden SOB, wheezing, distress RR30, tired, sats 93%, BP 140, anatomy easy • Type of airway? • Drugs? Intubation of the Asthmatic • Pretreatment – Lidocaine 1.5 mg/kg decreases bronchospastic response to laryngoscopy – Atropine 0.5 mg adult, 0.02 mg/kg peds to decrease airway secretions • Induction – Ketamine likely induction agent of choice – Pretreat with atropine to decrease secretions • Paralysis – Succinylcholine Post Intubation Management of the Asthmatic LOW AND SLOW!!!! RR 8-10 bpm, TV 6-8 ml/kg, Fi02 100%, PEEP ????, Inspiratory flow rate 100 L/min (usually 60 L/min) Watch peak inspiratory and plateau pressures Case: Fast Food Nation • I’m dead-sexy! • SOB NYD • Resp failure • What type of airway? • What drugs? • What position? • What back ups? DIFFICULT AIRWAY ALGORITHM Is the patient easy to bag? Do a "BVM trial" Call for help, Difficult airway cart Unable to maintain sats at 90%.... Go to Failed Airway Algorithm Blind NTI Awake Intubation or Sedation only "Triple Set up" "Quick Look" Prexoygenation Lidocaine neb/spray Light sedation prn Lidocaine neb/spray Light sedation and take a look RSI drugs ready Cric kit ready Positioning of the Morbidly obese • Picture 1 • Picture 2 Intubation of the Morbidly Obese • Be READY for a difficult airway • Starting with RSI is DANGEROUS! • Triple set up probably the best – Lidocaine neb, lidocaine spray, have RSI drugs ready, have all your back ups ready, do laryngoscopy, place the tube if you can • Why else is this a SCARY patient? Predictors of difficult BVM • • • • • B O N E S Beards Obesity, OSA Neck trauma, NO teeth Expectant (pregnant) Snores Be cautious with your RSI as your back-up of BVM may not be available! DIFFICULT INTUBATION + DIFFICULT BAG-VALVE-MASK VENTILATION Adam adam Wear your “Depends” • • • • Facial trauma Neck trauma Massive obesity Congenital or acquired airway anatomy anomalies Difficult Emergency Airway Managment • NEAR data (National Emergency Airway Registry) – Registry of 10,000 ED intubations – 97% of ED intubations are done by EP.s – RSI used in 85% of non-arrested pts – BNTI used in 5% of all intubations – 1-3% are difficult laryngoscopies – Oral ETT after RSI successful in 99.6% Back to the Fast Food Nation… You do your “awake” laryngoscopy and all you can see is a hint of the epiglottis, what do you do?????? What to do when you can’t see S… B B.U.R.P. B Bouigee B Big hockey stick on stylet B Blade change B “Better” physician B Back ups Case: Face vs Baseball bat • 30yo male • Assaulted • Head injured, facial smash, airway bloody, GCS 10, BP150 • “Underlying anatomy” looks ok • What type of airway? • What type of preparation? • What drugs? • How do things change is he is combative? Intubation with severe facial trauma • Can you bag the patient? • Oral intubation with RSI is usually successful but is a bit dangerous • Safest approach is likely “Triple Setup” – Local, draw RSI drugs, prep back ups, perform laryngoscopy, tube if you can or back off and do RSI if it isn’t too bad • What would your back ups be? – Bouigee, Trach light, LMA – BNTI contraindicated with severe facial trauma Case: I can’t breath • CHF, hypertensive, • CHF + Cardiogenic shock • Drugs? needs intubation • Pretreatment • Drugs? – Fluid bolus • Several induction – Have pressor ready or already going agents can be used • Induction agents limited – Ketamine (pretreat – Etomidate (full or ½ dose) with atropine) – Ketamine – Etomidate – No induction agent – Fentanyl/midazolam Controversies with Intubation of the CHF patient • Should you do an “awake” intubation – Advantages: less problems with hypotension from RSI drugs – Disadvantages: intubation is more difficult and takes longer; they don’t tolerate hypoxia during prolonged attempts very well – Recommendations: • RSI if anatomy looks easy • Awake if anatomy looks difficult Controversies with Intubation of the CHF patient • Should you leave the patient sitting – Advantages: avoids the large venous return with lying them down – Disadvantages: most people are less familiar with intubation in the sitting position and intubation may take longer – Recommendations: • Leave sitting if you are good at it • Otherwise, leave sitting initially, push RSI drugs, wait for full paralysis, lie down quickly and place the tube I can’t breath! Granny arrests just as you do the laryngoscopy…….. Why? Bradyasystolic arrests after intubation of the CHF patient • Why? – Large venous return as you lie them down – Vagal response to laryngoscopy and/or succinylcholine (patient already has maximal sympathetic tone and adrenals are “dry”) – Induction agent crashes their pressure – The patient was already dying • Take home points – Likely a combination of all of the above – Be ready for the patient to crash • Crash cart attached, fluid bolus, pressor ready, atropine ready Other difficult airways • • • • Airway Burns Anaphylaxis Angioedema Neck trauma – Blunt – Penetrating • Oral infections • Airway foreign bodies • Is Immediate transfer to OR available? • Is fiberoptic intubation in the ED available? • Key points for ED management – Approach as difficult airways – Call for back up and set up for surgical airway – Start with an “awake” intubation: RSI is an option if you look and see that the airway isn’t too bad Case: Head vs stairs • 30 yo male, fell down 15 stairs, intoxicated, vomited after, GCS 6, failed intubation by medics, LMA inserted • LMA in place, Sats 88%, AE equal, BP 150/70, prominent incisors, small chin, anterior larynx • What type of airway? • What drugs? • Grade 4 laryngoscopy with blood and vomit in the airway. Management? Case: Head vs stairs • Oral intubation attempts fail X 2 despite B.U.R.P. and blade change • Blind insertion of a gum elastic bouigee failed • What type of airway? • What is the key question now? • Management? THE FAILED AIRWAY ALGORITHM The FAILED AIRWAY = Unable to maintain sats > 90% with BVM 3 failed intubation attempts "Call for everything" -difficult AW cart -anesthesia, 2nd EP - cric kit +/- surgeon TIME (can bag, sats ok) Bouigee Trach light LMA Retrograde Fiberoptic I-LMA BNTI, combitube NO TIME (can't bag, sats dropping, patient crashing) Rescue LMA Surgical Airway Adults = cric or TTJV Peds = TTJV Case • 2 yo drowning • Full arrest • Is this a difficult airway? Children are different not difficult (generally)! Head Large occiput Oropharynx Large tongue, large tonsils, large adenoids, large and floppy epiglottis, sharp angle b/w epiglottis and glottis, Neck Anterior larynx, higher tracheal opening, cricoid ring is the narrowest part of the airway, small cricothyroid membrane, soft and flexible neck tissue, good neck mobility General More anatomic variation between ages Less anatomic variation between kids of the same age Fewer changes in airway with body habitus Other Higher metabolic rates, lower FRCs, quicker desaturation, higher tidal volumes Pediatric PEARLS • Intubation tricks – Inch down slowly: don’t go deep and then pull back – Provide your own B.U.R.P. – Beware that cricoid pressure from an assistant can really move the airway – Place an NG before: decompresses the stomach, makes it easier to back, may help you place the tube Pediatric PEARLS • EDD – Slow expansion is not a reliable indicator of esophageal intubaion in small kids because the trachea is too collapsible • Bouigee – The smallest tube it will fit through is a #5 Proper BVM in pediatrics: C-E position, lift the jaw to the mask, light pressure so you don’t occlude the airway, minor position changes important, properly sized equipment • WRONG! • RIGHT! C E What is the dose of midazolam in a 2 week old neonate? Braslow is your FRIEND in Exams and in Real life Pediatric Equipment, etc • Tube size • Blade size – – – – Premie 0-2 2-10 >10 Braslow (age/4 +4) Braslow 0 1 2 3 • Cuffed Braslow (>8yo) • Tube depth Braslow (ETT size X 3) Cuffed tubes in pediatrics is controversial • Several recent studies questioning the dogma that cuffed tubes are not used < 8yo • Cuffed tubes – High ventilation pressures: asthma, ARDS, post drowning What is unique about RSI in pediatrics? • Pretreatment – Atropine < 10yo, < 6 yo ??? – Preoxygenation important as they will desaturate quicker – Defasiculation generally not used • Paralytic – Remember that succ dose is higher • Infants/Children 2 mg/kg, neonates 3 mg/kg – Should rocuronium be used routinely in pediatric RSI? Succinylcholine versus Rocuronium for pediatric RSI • Succinylcholine – Faster onset (45 seconds) – Shorter duration (8 minutes) – Risk of hyperkalemia (especially with undiagnosed myopathies) • Rocuronium – Slower onset (1-2) min – Longer duration (3040 min, may decrease to 20 with reversal) – No hyperkalemia risk Positioning in pediatrics Case: “sore throat”, needs amoxil • • • • • • 4yo male Sore throat today Febrile, no cough Looks sick, anxious Tripod position Drooling, stridorous • Type of airway? • Management now? • Management after he completely obstructs? • ? OR management or ER management of the airway DIFFICULT PEDIATRIC AIRWAY ALGORITHM Is the patient easy to bag? Do a "BVM trial" Unable to maintain sats at 90%.... Go to Failed Airway Algorithm Blind NTI Call for help, Difficult airway cart Awake Intubation or Sedation only "Triple Set up" "Quick Look" Prexoygenation Lidocaine neb/spray Light sedation prn Lidocaine neb/spray Light sedation and take a look RSI drugs ready Cric kit ready Use the same approach to the difficult airway; BNTI is generally considered contraindicated in kids < 10yo THE FAILED PEDIATRIC AIRWAY ALGORITHM The FAILED AIRWAY = Unable to maintain sats > 90% with BVM 3 failed intubation attempts "Call for everything" -difficult AW cart -anesthesia, 2nd EP - cric kit +/- surgeon TIME (can bag, sats ok) BVM and wait for help LMA Bouigee if ETT > #5 Other adjuncts not commonly used in peds (I-LMA, trach light, fiberoptics) NO TIME (can't bag, sats dropping, patient crashing) Rescue LMA Surgical Airway > 10yo = cric or TTJV < 10 yo = TTJV Should Paramedics intubate kids? • Gausche. JAMA Feb 2000; 283(6): 783-90 – RCT of BVM vs ETT in pediatrics – N = 830 – Trends toward worse survival and neurological outcome in kids in ETT group – Critique: low rates of intubation, even/odd day randomization, short transport times – Take home: bag and drive unless long transport time TAKE HOME MESSAGES • Preparation is key • Prepare for the worst • Have a solid approach to the crash, easy, difficult and especially the FAILED AIRWAY • Kids are different, not difficult The End…