Emergency Airway Management Pat Melanson, MD - the most essential skill in EM - establishing or protecting on airway is frequently the essential maneuver for saving a person’s life - conversely, failure to do so is the fastest way to assure a patient’s demise - assessment and management of the airway have been appropriately assigned the A in the well known ABC’s of resuscitation for scientific reasons as well as alphabetic Emergency Airway Management Pat Melanson, MD

Safe airway management airway evaluation identification of the difficult airway assessment of other clinical factors selection of the likely most successful plan of action reasonable alternative plan

Algorithmic Approach to Airway Management Have a precompiled plan of airway management ready for implementation as clinical airway difficulties are encountered develop a plan and a back-up plan Practice guidelines for management of the difficult airway ASA taskforce Anesthesiology 78 : 597 - 602, 1993

Emergency Airway full stomach altered level of consciousness deteriorating cardiorespiratory physiology abnormal or distorted upper airway anatomy no time for pre-assessment or plan

Airway Assessment compromise or threats potentially difficult airway

The Three Pillars of Airway Management Patency ( airflow integrity ) Protection against aspiration Assurance of oxygenation and ventilation

Indications for Active Airway Intervention Patency - relief of obstruction Protection from aspiration Hypoxic/ hypercapnic respiratory failure Airway access for pulmonary toilet, drug delivery,therapeutic hyperventilation Shock

Clinical Signs of Airway Compromise : Patency Inspiratory stridor Snoring ( pharyngeal obstruction ) Gurgling ( foreign matter/ secretions ) Drooling ( epiglottitis ) Hoarseness ( laryngeal edema/ vc paralysis) Paradoxical chest wall movement Tracheal tug

Clinical Signs of Airway Compromise : Protection Blood in upper airway Pus in upper airway persistant vomiting Loss of protective airway reflexes

Clinical Signs of Airway Compromise: Oxygenation and Ventilation Central cyanosis Obtundation and diaphoresis rapid shallow respirations Accessory muscle use Retractions Abdominal paradox

The Difficult Airway Difficult laryngoscopy Difficult bag-mask ventilation Lower airway difficulty

Techniques for the Compromised Airway Bag-Valve-Mask Ventilation Endotracheal Intubation Rapid Sequence Intubation Alternate techniques for the difficult airway

Golden Rules of Bagging “ Anybody ( almost ) can be oxygenated and ventilated with a bag and a mask “ The art of bagging should be mastered before the art of intubation Manual ventilation skill with proper equipment is a fundamental premise of advanced airway management

Frequent Errors with BVM failure to recognize its importance forget to bag ( focussed on ETT ) give up on bagging too early bag but don’t assess efficacy failure to assign one person to airway management only

Difficult Airway : BVM Upper airway obstruction Lack of dentures Beard Midfacial smash facial burns, dressings, scarring poor lung mechanics

Difficult Airway : BVM degree of difficulty from zero to infinite zero = no external effort/internal device one person jaw thrust/ face seal oropharyngeal or nasopharyngeal AW two person jaw thrust / face seal both internal airway devices infinite -no patency despite maximal external effort and full use of OP/NP

Difficult Airway : BVM Remove FB - Magill forceps Triple maneuver if c-spine clear Head tilt, jaw lift, mouth opening Nasopharyngeal or oropharyngeal airway two-person, four-hand technique

Prediction of the difficult airway (Intubation) 1200 prospectively studied patients of 84 patients predicted to have problem, only 22 (25%) actually had a problem of 43 actual difficult intubations incurred, only 22 (51%) were predicted Latto IP. and Rosen M

Prediction of the difficult airway history of past airway problems Careful physical assessment knowledge and experience to overcome the "unpredicted difficult airway". learning practical airway management skills in an environment that is not urgent, stressful or life threatening

Difficult Airway : Laryngoscopy Short thick neck Receding mandible Buck teeth Poor mandibular mobility/ limited jaw opening Limited head and neck movement ( including trauma ) C. Direct laryngoscopy will be made difficult by: •decreased mobility cervical spines •tempero-mandibular jt •larynx •decreased visualization oral structures •mandibular structures •laryngeal tilt •dentition •secretions •airway obstruction pharyngeal •laryngeal •tracheal

Difficult Airway : Laryngoscopy Tumor, abscess or hematoma Burns Angioneurotic edema Blunt or penetrating trauma Rheumatoid arthritis, ankylosing spondylitis Congenital syndromes Neck surgery or radiation

Difficult Airway : Laryngoscopy 3 fingerbreadths mentum to hyoid 3 fb chin to thyroid notch 3 fb upper to lower incisors Head extension and neck flexion Mallimpadi classification Previous history of difficult intubation

Mallimpadi Classification ( Tongue to Pharyngeal Size ) I - soft palate, uvula, tonsillar pillars 99 % have grade I laryngoscopic view II - soft palate, uvula III - soft palate, base of uvula IV - soft palate not visible 100% grade III or grade IV views

Unsuccessful Intubation Bag the patient Maximize neck flexion/ head extension Move tongue out of line of site Maximize mouth opening Look for landmarks and adjust blade BURP maneuver increasing lifting force consider Miller blade - improper positioning is the most common reason for inability to visualize the cords - second most common cause is haste in the intubation process - slow down and perform each maneuver deliberately and attempt to visualize landmarks along the way - lateral landmarks ( aryepiglottic folds, tonsillar pillars move towards the midline ( elevate occiput 10 cm )/ 45 degrees neck flexion - blade too far - - if in esophagus will see no landmarks except general mucosal tissue - Mac blade on epiglottis- base of epi9glottis will continue to obscure cords - hockey stick angulation - look for bubbles - gum rubber bouge - fiberoptic, digital, lighted stylet, surgical airway

Dilemmas: Awake or Asleep Oral or Nasal Laryngoscopy or Blind Intubation To Paralyze or Not

Case #1 43 year old female, day 12 post SAH 5 unclipped cerebral aneurysms vasospasm with left hemiparesis hydrocephalus with clotted IV drain rising ICP and BP decreasing LOC ate breakfast

Techniques DL without pharmacologic aids Awake Direct Laryngoscopy Awake Blind Nasal Rapid Sequence Intubation (RSI) Fiberoptic Surgical Cricothyroidotomy

Anesthesia Airway Maxims the awake airway is the safest to manage spontaneous breathing is generally safer than paralysis with PPV by mask have a low threshold to wake the patient up and cancel the case call for help early

The “Intubation Reflex “ Catecholamine release in response to laryngeal manipulation Tachycardia, hypertension, raised ICP Attenuated by beta-blockers, fentanyl ICP rise possibly attenuated by lidocaine Midazolam and thiopental have no effect

Rapid Sequence Intubation : Definition The near simultaneous administration of a sedative-hypnotic agent and a neuromuscular blocker in the presence of continuous cricoid pressure to facilitate endotracheal intubation and minimize risk of aspiration modifications are made depending upon the clinical scenario

Rapid Sequence Intubation : Advantages Optimizes intubating conditions/ facilitates visualization Increased rate of successful intubation Decreased time to intubation Decreased risk of aspiration Attenuation of hemodynamic and ICP changes

Rapid Sequence Intubation : Contraindications Anticipated difficulty with endotracheal intubation anatomic distortion Lack of operator skill or familiarity inability to preoxygenate

Rapid Sequence Intubation : Procedure Pre-intubation assessment Pre-oxygenate Prepare ( for the worst ) Premedicate Paralyze Pressure on cricoid Place the tube Post intubation assessment

Pre-oxygenate ( Time - 5 Minutes) 100 % oxygen for 5 minutes 4 conscious deep breaths of 100 % O2 Fill FRC with reservoir of 100 % O2 Allows 3 to 5 minutes of apnea Essential to allow avoidance of bagging If necessary bag with cricoid pressure

Preparation ( Time - 5 Minutes ) ETT, stylet, blades, suction, BVM Cardiac monitor, pulse oximeter, ETCO2 One ( preferably two ) iv lines Drugs Difficult airway kit including cric kit Patient positioning

Pre-treatment/ Prime ( Time - 2 Minutes ) Lidocaine 1.5 mg/kg iv Defasciculating dose of non-depolarizing NMB Beta-blocker or fentanyl Induction agent Thiopental 3 - 5 mg/kg Midazolam 0.1 - 0.4mg/kg Ketamine 1.5 - 2.0 mg/kg Fentanyl 2 - 30 mcg/kg

Paralyze ( Time Zero ) Succinylcholine 1.5 mg/kg iv Allow 45 - 60 seconds for complete muscle relaxation Alternatives Vecuromium 0.1 - 0.2 mg/kg Rocuronium o.6 - 1.2 mg/kg

Pressure Sellick maneuver initiate upon loss of consciousness continue until ETT balloon inflation release if active vomiting

Place the Tube ( Time Zero + 45 Secs ) Wait for optimal paralysis Confirm tube placement with ETCO2

Post-intubation Hypotension Loss of sympathetic drive Myocardial infarction Tension pneumothorax Auto-peep

Succinylcholine : Contraindications Hyperkalemia - renal failure Active neuromuscular disease with functional denervation ( 6 days to 6 months) Extensive burns or crush injuries Malignant hyperthermia Pseudocholinesterase deficiency Organophosphate poisoning

Succinylcholine : Complications Inability to secure airway Increased vagal tone ( second dose ) Histamine release ( rare ) Increased ICP/ IOP/ intragastric pressure Myalgias Hyperkalemia with burns, NM disease malignant hyperthermia

Difficult Airway Kit Multiple blades and ETTs ETT guides ( stylets, bougé, light wand) Emergency nonsurgical ventilation ( LMA, combitube, TTJV ) Emergency surgical airway access ( cricothyroidotomy kit, cricotomes ) ETT placement verification Fiberoptic and retrograde intubation

Emergency Surgical Airway Maxims they are usually a bloody mess, but ... a bloody surgical airway is better than an arrested patient with a nice looking neck

Case # 2 42 year old female right Pancoast tumor RUL, RML, RLL collapse ARDS on left hypoxemic respiratory failure cord compression C7 - T4