Author:
Thomas L.Knorr
Carlo L.Rosen
Description
- Techniques that ensure adequate oxygenation and ventilation
- Oral and nasopharyngeal airways:
- Lift tongue off hypopharynx
- Facilitate bag-valve-mask (BVM) ventilation
- Insert when gag reflex is absent
- RSI:
- Preferred method for ED oral intubation (minimizes aspiration risk)
- Rapid induction of anesthesia and paralysis
- Contraindicated in patients who should not be paralyzed
- A preformulated backup strategy with alternative airway techniques is essential
- Use of fiberoptic techniques maximizes success
- Oral awake intubation:
- Oral intubation with sedation only
- Use when paralysis is contraindicated
- Ketamine is most commonly used
- Gum elastic bougie:
- Airway adjunct used when vocal cords are not well visualized
- Placement confirmed by feeling bougie bump against tracheal rings
- Slide endotracheal tube (ET) over bougie, then remove bougie
- Alternative airway devices:
- Extraglottic devices:
- Inserted blindly into oropharynx and inflated
- Laryngeal mask airway (LMA) forms a seal around glottic structures in hypopharynx
- LMA offers less protection against aspiration than ET tube
- Intubating LMA can be used to place an ET tube
- Esophageal-tracheal tubes (e.g., Combitube, King LT) occlude the esophagus and ventilate the hypopharynx
- Video laryngoscopes:
- Fiberoptic camera on the tip of laryngoscope blade (e.g., Glidescope, C-MAC) or LMA to visualize tube placement
- Fiberoptic intubating stylets:
- Fiberoptic camera on the tip of a stylet which holds ET tube (e.g., Shikani)
- Classic fiberoptic intubation:
- ET tube placed over bronchoscope
- Nasotracheal or orotracheal approach
- Indications:
- Anatomic limitations to glottis visualization
- Limited mobility of mand ible or cervical spine
- Unstable cervical spine injury
- Contraindications:
- Need for immediate airway management
- Significant oropharyngeal blood
- Nasotracheal intubation:
- Indications:
- Oral access impaired
- Unsuccessful oral intubation
- Paralysis is contraindicated
- Limited cervical mobility
- Contraindications:
- Apnea (only absolute contraindication)
- Anticoagulation
- Massive facial, nasal, or head trauma
- Upper airway abscess
- Epiglottitis
- Penetrating neck trauma
- Cricothyrotomy:
- Definitive treatment for a failed airway
- Incision in cricothyroid membrane
- Tracheostomy tube inserted percutaneously into the airway
- Indications:
- Crash airway when other airway attempts fail
- Massive facial trauma
- Total upper airway obstruction
- Contraindications:
- Laryngeal crush injury
- Tracheal transection
- Relative: Expand ing zone II or III hematoma
- Noninvasive positive pressure ventilation:
- Ventilatory support without use of an invasive artificial airway
- Typically via facemask or nasal piece
- Indications:
- Cooperative patient
- Prehospital undifferentiated dyspnea
- Most effective for conditions which respond quickly to treatment (COPD and CHF)
- Contraindications:
- Intractable emesis
- Upper airway obstruction
- Inability to protect airway or clear secretions
- Hemodynamic instability
- Altered mental status or coma
- Cardiac or respiratory arrest
- High-flow nasal oxygen:
- Heated, humidified high-flow oxygen provides increased comfort vs. conventional nasal cannula
- Provides FiO2 up to 1.0 at 60 L/min
- Provided minimal positive end expiratory pressure
- Indications:
- Hypoxemic respiratory failure without hypercapnia
- Contraindications:
- Epistaxis
- Nasal obstruction
- Basilar skull fracture
- Recent surgery to nares or aerodigestive tract
- Percutaneous translaryngeal ventilation (PTV):
- Percutaneous placement of 12G or 14G catheter through cricothyroid membrane
- Intermittent ventilation via high-pressure oxygen source
- Indications:
- Failed oral or nasal intubation until cricothyrotomy is complete
- Contraindications:
- Upper airway obstruction preventing expiration
Signs and Symptoms
Clinical conditions requiring airway management:
- Failure to maintain or protect the airway:
- Oropharyngeal swelling
- Absent gag reflex
- Inability to clear secretions, blood
- Stridor
- Hypoxia or ventilatory failure:
- Shortness of breath
- Altered mental status
- Status epilepticus
- Anticipated clinical course:
- Ventilatory control for head injury or tricyclic overdose
- Sedation for diagnostic or therapeutic procedures
- Early management if the airway might become compromised
Essential Workup
- Always be prepared with a difficult airway algorithm prior to beginning the procedure.
- Recognition of a difficult airway (LEMON):
- LOOK for anatomic considerations:
- Short mand ible, thick neck, narrow mouth, large tongue, and protruding teeth
- Congenital syndromes, acromegaly
- Obesity
- EVALUATE 3-3-2 rule (difficult airway if met):
- Mouth opens <3 fingerbreadths
- Horizontal length of mand ible <3 fingerbreadths
- Thyromental distance <2 fingerbreadths
- MALLAMPATI criteria (increasing difficulty):
- Class I: Soft palate, uvula, fauces, pillars visible
- Class II: Soft palate, uvula, fauces visible
- Class III: Soft palate visible
- Class IV: Hard palate only
- OBSTRUCTION from underlying disease states:
- NECK mobility limitation:
- Rheumatoid arthritis and other arthropathies that decrease cervical spine mobility
- Spinal immobilization for trauma
- Verification of correct tube placement:
- Visualization of tube passing through the vocal cords
- Tracheal tube depth (tube tip to upper incisors):
- 21 cm (women)
- 23 cm (men)
- Age (yr)/2 + 12 (children)
- End-tidal CO2 colorimetric device:
- Changes color if CO2 is present, indicating tracheal placement
- Color change may not be seen in cardiac arrest
- Auscultate over stomach, axillae, and anterior lung fields
- Observe chest wall movement
- Condensation in the tube during ventilation
Diagnostic Tests & Interpretation
Lab
- Pulse oximetry should rise after tracheal intubation
- Continuous capnography used as adjunct
- Arterial blood gas to manage ventilator settings after intubation
Imaging
CXR:
- To exclude mainstem bronchus intubation or pneumothorax
- Does not rule out esophageal intubation
Diagnostic Procedures/Surgery
Direct visualization of the ET tube through the cords is gold stand ard
Differential Diagnosis
- Esophageal intubation
- Right or left mainstem bronchus intubation
- Extratracheal placement through tear in pyriform sinus or trachea
- Pneumothorax
Prehospital
Options for patients in respiratory arrest for advanced life support (ALS) providers:
- Bag-valve management (BVM) ventilation followed by definitive airway management in the ED
- Orotracheal intubation
- Esophageal-tracheal tubes
- LMA
Initial Stabilization/Therapy
- Maintain inline cervical spine immobilization in trauma
- Oxygen, monitor, IV
ED Treatment/Procedures
- RSI:
- Simultaneous administration of sedation (induction agent) and paralysis to provide optimal conditions for emergency airway management
- Prepare equipment:
- Suction, BVM, various sizes of ET tubes and laryngoscope blades, stylets, medications, and backup devices
- Preoxygenation:
- 100% FIO2 for 3 min prior to induction and paralysis
- Apneic oxygenization after paralysis via nonrebreather and nasal cannula
- Pretreatment:
- Prevents physiologic sequelae of intubation
- Performed 3 min prior to paralytic
- Defasciculating dose of nondepolarizing agent
- Fentanyl and lidocaine may minimize ICP rise and hemodynamic response to intubation in head-injured patients
- Lidocaine and albuterol in reactive airway disease
- Paralysis with induction:
- Administration of induction agent (e.g., etomidate, thiopental, midazolam, ketamine)
- Rapidly followed by administration of paralytic agent (e.g., succinylcholine, rocuronium):
- Succinylcholine is relatively contraindicated with anticipated difficult oral intubation, open globe injury, organophosphate poisoning, burns >3 days old, denervation syndromes, myopathies, and suspected hyperkalemia
- Nondepolarizing agents (e.g., rocuronium) can be used as an alternative to succinylcholine
- Positioning:
- Head extension, with midline cervical stabilization if trauma patient
- Cricoid pressure (Sellick maneuver) is controversial and optional
- Placement of tube:
- After muscle tone is lost (45-60 s after succinylcholine)
- Use a stylet with the ET tube
- Place tube through vocal cords
- Inflate cuff
- Begin ventilation
- Confirm correct ET tube placement
- Postintubation:
- Benzodiazepines, opiates, or propofol used for continued sedation
- Vecuronium may be used for continued paralysis
Pediatric Considerations |
- Estimation of ET tube size: 4 + age/4
- Uncuffed ET tubes may be used in patients <8 yr old
- Straight Miller blade is preferred in patients <3 yr old
- Cricothyrotomy contraindicated in patients <12 yr old; PTV is preferred
- Use atropine as pretreatment to reduce secretions and attenuate vagal effect
- A defasciculating neuromuscular blocking agent not necessary for children <5 yr old
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Medication
- Atracurium: 0.4-0.5 mg/kg IV
- Atropine: 0.02 mg/kg IV
- Diazepam: 2-10 mg (peds: 0.2-0.3 mg/kg) IV
- Etomidate: 0.3 mg/kg IV
- Fentanyl: 3 mcg/kg IV
- Ketamine: 1-2 mg/kg IV or 4-7 mg/kg IM
- Lidocaine: 1.5 mg/kg IV
- Midazolam: 1-5 mg IV (0.07-0.30 mg/kg for induction)
- Propofol: 2-2.5 mg/kg IV
- Pancuronium: 0.01 mg/kg IV (defasciculating dose); 0.1 mg/kg IV (paralyzing dose)
- Rocuronium: 1 mg/kg IV
- Succinylcholine: 1.5 mg/kg (peds: 2 mg/kg) IV; 2.5 mg/kg IM/SC
- Thiopental: 3 mg/kg IV
- Vecuronium: 0.01 mg/kg IV (defasciculating dose); 0.1 mg/kg IV (paralyzing dose)
Disposition
Admission Criteria
Almost all intubated patients should be admitted to an ICU
Discharge Criteria
Rarely, certain ED patients who have been intubated for airway protection or to facilitate diagnostic workup may be extubated in the ED after a period of observation and then discharged
- BrownCA, WallsRM. Airway. In: WallsRA, HockbergerRS, Gausche-HillM, et al., eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed.Philadelphia, PA: Mosby Elsevier; 2018.
- DriverBE, ReardonRF, et al. Basic airway management and decision-making. In: RobertsJR, HedgesJR, eds. Clinical Procedures in Emergency Medicine and Acute Care. 7th ed.Philadelphia, PA: Saunders Elsevier; 2019.
- FrerkC, MitchellVS, McNarryAF, et al. Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults . Br J Anaesth. 2015;115:827-848.
See Also (Topic, Algorithm, Electronic Media Element)
Rapid Sequence Intubation
ICD9
96.01 Insertion of nasopharyngeal airway
96.02 Insertion of oropharyngeal airway
96.05 Other intubation of respiratory tract
ICD10
0CHY7BZ Insertion of Airway into Mouth and Throat, Via Natural or Artificial Opening
SNOMED
426153007 insertion of artificial airway (procedure)
7443007 insertion of oropharyngeal airway (procedure)
182692007 nasopharyngeal airway insertion (procedure)