Airway management

Airway management is the practice of evaluating, planning, and using a wide array of medical procedures and devices for the purpose of maintaining or restoring a safe, effective pathway for oxygenation and ventilation. These procedures are indicated in patients with airway obstruction, respiratory failure, or a need for airway protection (e.g., for general anesthesia or due to an aspiration risk).

Basic airway maneuvers are the most important first step and consist primarily of positioning, supplemental oxygen, and bag-mask ventilation with or without adjuncts. Patients with serious or persistent airway compromise typically require advanced airway devices, which consist of supraglottic devices, endotracheal tubes, and surgical airway devices.

In endotracheal intubation, a tube is inserted orally (or nasally) into the trachea to allow gas exchange, often via mechanical ventilation. The tube can be placed under direct visualization with the help of a laryngoscope or with video-assisted laryngoscopy. Correct placement is established based on multiple measurements, including exhaled CO₂ and evidence of bilateral breath sounds on auscultation. Common complications of endotracheal intubation include hypoxia, hypotension, airway trauma, accidental esophageal intubation, and aspiration.

Surgical airways may be performed in an emergency, particularly as part of a cannot intubate, cannot ventilate (CICV) scenario, or placed for long-term mechanical ventilation. Patients with surgical airways are vulnerable to a sudden loss of the airway due to displacement or blockage of the tubes with secretions.

See also “Cricothyrotomy.”

Airway management is used for patients with signs of airway obstruction and for patients whose airway is considered at-risk due to a potential loss of protective airway reflexes. See “Clinical features of partial airway obstruction” and “Clinical features of complete airway obstruction” for details.

Red flags for an at-risk airway ^[1][2]

• Loss of airway protective reflexes
  • Reduced level of consciousness (traditionally GCS ≤ 8) ^[3][4]
  • Ability to comfortably tolerate an oral airway
  • Inability to swallow secretions
  • Procedural sedation and/or general anesthesia
• Airway obstruction
  • Facial trauma
  • Burn injury and/or inhalational injury ^[5]
  • Progressive angioedema ^[6]
  • Known or suspected foreign body aspiration
  • Known laryngeal or pharyngeal cancer

Urgently manage acute or rapidly-progressive stridor as it can indicate > 50% airway obstruction with a high risk of respiratory failure and difficult intubation. ^[1][7][8]Continuously monitor patients with red flags for an at-risk airway and exercise caution when transporting these patients away from a supervised setting, (e.g., for imaging studies). ^[2]

• Basic airway maneuvers are used:
  • To relieve partial airway obstruction in obtunded but spontaneously breathing patients
  • As a temporary measure prior to placement of a definitive airway in apneic patients or those with profound respiratory failure
• All patients require monitoring with pulse oximetry.
• Most patients should receive supplemental oxygen (see “Oxygen therapy”).
• Patients requiring basic airway maneuvers are at high risk of further airway deterioration; prepare for an advanced airway for most patients.

These maneuvers may be used alone or combined with basic airway adjuncts and bag-mask ventilation.

Head-tilt/chin-lift maneuver ^[9]

• Description: repositioning the head and neck to open the airway
• Technique
  1. Tilt the patient's head posteriorly to 15–30° of atlantooccipital extension.
  2. Lift the chin with the fingers to pull the tongue and oropharyngeal soft tissue anteriorly.
  3. Use the thumb of the same hand to apply pressure below the lip, slightly opening the mouth.
  4. Maintain this “sniffing position” to align the oral, pharyngeal, and laryngeal axes.
• Contraindication: suspected cervical spine injury

Jaw-thrust maneuver

• Description
  • Displacing the mandible and tongue anteriorly to open the airway
  • May be used in conjunction with head-tilt/chin-lift or alone in patients with suspected C-spine injury
• Technique
  1. With the patient supine, place fingers behind the angles of the lower jaw.
  2. Move the jaw anteriorly to pull the base of the tongue and soft tissues away from the airway.
  3. Use the thumbs to open the mouth slightly.

After airway opening maneuvers have been performed, observe for signs of adequate ventilation and oxygenation (e.g., chest rise, audible air movement, positive waveform on capnography, SpO₂ in target range).

Recovery position

Used only in spontaneously breathing patients

• Description: positioning of the patient in a lateral decubitus position with slight neck extension
• Goal
  • Prevention of airway occlusion by the tongue and soft tissues
  • Reduction in the risk of aspiration the patient regurgitates
• Indication: temporary airway compromise that can be reversed with positioning (e.g., due to procedural sedation or acute alcohol intoxication)
• Contraindications
  • C-spine immobilization
  • Anticipated worsening of airway compromise
  • Transportation outside of a monitored environment

Definition ^[10][11]

Delivery of positive pressure ventilation to patients with absent or impaired respiratory effort using a bag-valve-mask unit

Indications ^[10][11]

• Rescue ventilation: cardiac arrest, respiratory failure, accidental oversedation, failed intubation attempt (i.e., when safe apnea time has been exceeded)
• Bridge to intubation: following induction of apnea by administration of sedatives and muscle relaxants

Procedure

Create a mask seal

• EC-clamp technique (one-person technique): commonly used in elective perioperative situations when the provider is alone
  1. With the patient supine, lift the jaw towards the mask using the 3^rd, 4^th, and 5^th fingers of one hand, forming an E-shape.
  2. Squeeze the mask onto the face with the thumb and index finger of the same hand, forming a C-shape.
  3. Deliver breaths with the second hand.
• Two-person bag-mask-ventilation technique: used in emergency settings in which the patient is deteriorating or ventilation is difficult, since it is more effective ^[12][13][14]
  • One provider makes a seal and opens the airway with both hands:
    • Press the mask firmly against the face with both thumbs.
    • Simultaneously perform a jaw thrust maneuver with all 4 fingers of both hands.
    • A two-handed EC-clamp technique may also be used. ^[15]
  • The second provider delivers breaths.

Initiate ventilation

• Goal ^[16][17]
  • Adults: 500–600 mL (6–7 mL/kg) tidal volume at 10–12 breaths/minute
  • Children: 20–30 breaths/minute
• Technique
  • Compress bag over approx. 1 second then allow it to fully reinflate.
  • Repeat every 5 seconds in adults and 2–3 seconds in children.
  • Adjust based on clinical situation (e.g., a compression-to-breath ratio of 30:2 if the patient is receiving chest compressions)

Confirm adequacy of BMV

• Clinical
  • No audible air leak around mask
  • Bilateral chest rise
  • Air entry on auscultation of bilateral lung fields
• Monitor
  • SpO₂ in target range (may be above normal if preoxygenating)
  • Normal capnometry (waveform and EtCO₂ value)

Ensure oxygen is attached to the bag-mask apparatus!

Pitfalls and troubleshooting

Efficacy of BMV may be affected by provider technique or patient factors (such as obesity, reduced lung compliance, or craniofacial abnormalities).

Factors that contribute to difficult BMV can be remembered with the MOANS mnemonic: Mask seal, Obstruction/Obesity, Age > 55 years, No teeth, Stiff lungs/Sleep apnea.

These devices may be used in combination with airway opening maneuvers to improve airway patency.

Oropharyngeal airway (OPA) ^[9]

• Description: a rigid curved device placed in the mouth to prevent the tongue from occluding the airway
• Indications
  • Unconscious patient with airway obstruction (e.g., due to a large tongue, excessive nasopharyngeal tissue, copious secretion)
  • Typically used as a bridge to intubation
• Contraindications: conscious patient with intact gag reflex
• Sizing rule: from the incisors to the angle of the mandible, or corner of the mouth (oral commissure) to the earlobe
• Insertion technique
  • Adults: Insert concave up or concave lateral until past the tongue and then rotate until concave down.
  • Children: Using a tongue depressor to move the tongue down, insert carefully concave down.
  • Ensure OPA has bypassed the tongue and is not pushing it backwards.
• Further management: Toleration of an oropharyngeal airway indicates an at-risk airway; preparations should be made for intubation.

Nasopharyngeal airway (NPA) ^[9]

• Description: a soft flexible tube inserted through the nares into the nasopharynx to prevent the tongue from occluding the airway
• Indications: current or potential oropharyngeal obstruction
• Contraindications ^[2][18]
  • Facial fractures, basilar skull fractures
  • Coagulopathy
• Sizing rule: nostril to the ipsilateral tragus
• Insertion technique
  1. Lubricate the tube.
  2. Consider topical decongestant to decrease the risk of epistaxis (e.g., oxymetazoline ). ^[19]
  3. Select the wider nostril.
  4. Insert gently without forcing.
  5. Aim posteriorly, not superiorly.
  6. Twist the tube back and forth for ease of passage.
  7. If resistance is encountered, stop and attempt on the contralateral nostril.

Definition

Advanced airway devices that occlude the distal oropharynx to facilitate positive pressure ventilation in the absence of an endotracheal tube

Indications

• Prehospital advanced airway management, e.g., out-of-hospital cardiac arrest
• Failed endotracheal intubation
• Surgical procedures requiring general anesthesia but not endotracheal intubation

Contraindications

• Epiglottitis
• Avoid in conscious patients with an intact gag reflex.

SGAs offer less protection against aspiration than ET tubes.

Options ^[11][20]

• Laryngeal mask airway (LMA): a supraglottic device consisting of an inflatable mask attached to the end of a tube
  • Second-generation LMAs have safety adaptations such as bite blocks and gastroesophageal drainage ports.
  • Intubating LMAs (ILMAs) have adaptations that allow passage of an ET tube through the LMA.
• i-gel®: A type of supraglottic airway; similar to the LMA, but the mask is anatomically-molded, noninflatable, and made of a soft gellike material.
• Laryngeal tube airway (LTA)
  • An airway device consisting of a tube with two inflatable cuffs and ventilation holes between them.
  • Intubating LTAs feature additional adaptations to allow the passage of an ET tube through the LTA. ^[21]

Procedure ^[1][11]

1. Choose the appropriate size for the patient:
   • Small adult: size 3
   • Medium adult: size 4
   • Large adult: size 5
2. LMAs and LTAs: inflate cuffs fully to check for leaks before deflating.
3. Lubricate the tip of the device, being careful not to block ventilatory openings.
4. Place the patient in the sniffing position.
5. Open the patient's mouth wide.
6. Hold the device firmly (at the junction of the tube and mask for an LMA, at the bite block for an i-gel®, or at the connector for an LTA).
7. Insert the device.
   • LMA and i-gel®: Insert smoothly along the hard palate and downwards with the outlet facing caudally.
   • LTA: Insert the tube rotated at 45–90° from midline (towards concave lateral) until past the base of the tongue, where it should be rotated back to midline (towards concave up).
8. Stop when the device has passed the base of the tongue and resistance is felt (LMA or i-gel®) or the connector reaches the teeth (LTA).
9. LMAs and LTAs: Inflate the cuff.
10. Confirm supraglottic tube placement.

Confirmation of correct placement ^[22]

• Air movement heard on auscultation of chest
• Visible chest rise and fall
• Continuous CO₂ waveform on capnography
• Stable or improving oxygenation

The distal end of the LTA may pass blindly into the trachea. Confirmation of correct placement is always necessary.

Troubleshooting the LMA ^[22]

Difficulty ventilating the patient through a supraglottic airway suggests the device is malpositioned.

• Reposition the patient's head and neck and/or perform airway opening maneuvers.
• Deflate and reinflate mask (cuff may be hyperinflated or hypoinflated).
• Withdraw, advance, or rotate the device.
• Remove and reinsert the device or change size (a larger size may be required).
• Switch to a different airway adjunct.

Definitions ^[1][11]

• Endotracheal tube (ET tube): a flexible hollow tube designed to enter the trachea via the oropharynx or the nasopharynx, facilitate gas exchange, and protect the airway from aspiration
• Endotracheal intubation: placement of an ET tube in the trachea below the vocal cords
  • Orotracheal intubation: most common
  • Nasotracheal intubation: used in select conditions
  • Insertion usually assisted by direct laryngoscopy, video laryngoscopy , or flexible fiberoptic laryngoscopy
  • Typically requires sedation and paralysis ^[23]
  • Often preceded by BMV in fasting patients (e.g., elective surgery)
• Rapid sequence intubation/induction (RSI): commonly used when patients are at risk of aspiration
  • Goals: maximize first-pass success, reduce the risk of aspiration
  • Technique: rapid induction of anesthesia and paralysis followed by immediate intubation without intervening attempts at ventilation ^[24][25]
  • Differences from traditional intubation
    • Weight-based bolus doses of short-acting intubation medications are used without titration.
    • BMV is not performed

Indications for endotracheal intubation ^[1]

• Airway obstruction: e.g., anaphylaxis, peritonsillar abscess, angioedema
• Airway protection
  • Loss of airway protective reflexes: e.g., general anesthesia, persistent causes of AMS or coma
  • High risk of aspirating blood or secretions: e.g., hematemesis, massive hemoptysis, posttonsillectomy hemorrhage, uncontrollable vomiting
  • Anticipated deterioration: e.g., smoke inhalation injury, overdose
• Indications for invasive mechanical ventilation: : e.g., respiratory failure, respiratory arrest, multisystem trauma, septic shock

Contraindications

• Absolute: Presence of a valid do-not-intubate order and/or DNAR order
• Relative
  • Avoid RSI in certain types of difficult airways where rapid induction could precipitate a CICV scenario.
  • Avoid nasotracheal intubation in patients with facial and basal skull fractures. ^[26]

Complications

Mainstem intubation

• Definition: the placement of the distal end of an endotracheal tube into either the right or left main bronchus
• Etiology: inadvertent placement during intubation
• Clinical features
  • Hypoxia
  • Asymmetric breath sounds
  • High peak pressures
• Management: repositioning of the endotracheal tube

Preassessment ^[1][27]

• Identify any red flags for difficult airway management, e.g., using the LEMON assessment.
• Call an airway management expert if a difficult airway is anticipated.
• Ensure necessary equipment is available and functioning (see “Equipment checklist for intubation”).

Before attempting intubation, remember to review the SOAP ME checklist: Suction, Oxygen, Airway equipment, Pharmacy, Monitoring, and Equipment for resuscitation.

If red flags for a difficult airway are present, call for help, consider using adjuncts for difficult airway, or proceed to a surgical airway.

Preoxygenation ^[28]

• Definition: administration of 100% oxygen prior to induction ^[29]
• Goals
  • Lengthen safe apnea time: the period during which patients can safely go without spontaneous breathing, i.e., between induction and successful ET tube placement ^[28]
  • Prevent critical desaturation and subsequent organ dysfunction or death
• Target SpO₂: as close to 100% as possible
• Methods ^[30]
  • First line: High flow O₂ (10–12 L/min) via NRB for 3 minutes
  • Alternative (if 3 minutes of preoxygenation is not possible): 8 breaths (vital capacity inspirations)

Once preoxygenation has begun, keep the mask firmly applied to the face in order to obtain the maximum benefit.

Preoxygenation is vital for patients with risk factors for rapid desaturation during the apneic period (e.g., critical illness, obesity, preexisting lung disease).

Intubation medications ^[1][11]

Typically two classes of medication are given prior to intubation, a sedating (induction) agent and neuromuscular blocking agent to paralyze the patient.

Induction agents for intubation ^[1]

• Sedates the patient, thereby reducing airway reflexes and facilitating intubation
• Commonly used agents include propofol, etomidate, and ketamine.
• The choice of induction agent depends on patient characteristics and operator experience.
• The duration of bolus doses is typically short (∼ 10 minutes) and infusions or repeat bolus dosing are required for ongoing sedation (see “Adjunctive care of ventilated patients” for suggested medications and doses).

Midazolam and fentanyl are not routinely recommended for intubation due to their unpredictable effectiveness and high risk of adverse events.

Paralytic agents for intubation ^[1]

• Benefits
  • Better visualization of glottic opening
  • Decreased risk of airway injury
• Classes of neuromuscular junction blockers (NMJ blockers)
  • Depolarizing NMJ blockers (e.g., succinylcholine )
    • Commonly used because of rapid onset and offset time (spontaneous respirations normally return within 10 minutes)
    • May precipitate severe hyperkalemia in patients with contraindications to succinylcholine
    • Rarely, prolonged paralysis occurs in patients with limited cholinesterase activity.
  • Nondepolarizing NMJ blockers: e.g., rocuronium
    • Indicated in patients with contraindications to succinylcholine
    • May be used as a first-line muscle relaxant in all patients.
    • Typically avoided in patients with a suspected difficult airway because they have a longer duration of action (risk of deterioration to a CICV scenario). ^[34]
• If ongoing paralysis is required, an infusion is necessary (see “Adjunctive care of ventilated patients” for suggested medications and doses).

Avoid succinylcholine in at-risk patients (i.e., those with renal impairment, burns, crush injuries, denervation, neuromuscular disease, prolonged abdominal sepsis) because it can cause life-threatening hyperkalemia! ^[1]

Direct laryngoscopy is the traditional first-line approach to intubation, however, in many centers, videolaryngoscopy is preferred and performed routinely.

Intubation via direct laryngoscopy ^[11]

• Positioning: Place patient in sniffing position unless C-spine injury is suspected.
  • Head elevated to a height of 10 cm
  • The neck is mildly flexed at the lower cervical vertebrae and extended at the atlanto-occipital joint.
• Technique: The majority of patients should have received induction agents and been preoxygenated.
  1. Wear appropriate PPE.
  2. Choose the correct ET tube size. ^[35]
  3. Gently open the patient's mouth.
  4. Insert the laryngoscope blade , using the groove to sweep the tongue aside.
  5. Advance steadily until the tip is at the vallecula and the epiglottis is visible below it.
  6. Lift gently forward and upward to raise the epiglottis and reveal the arytenoid cartilages and vocal cords.
  7. Insert the styleted ET tube.
  8. Once the tip is at the glottis, remove the stylet and gently advance until the cuff is past the cords.
  9. Inflate the cuff.
  10. Secure the tube once proper placement is confirmed.

Avoid rocking the laryngoscope on the teeth; it can cause dental injury and aspiration of tooth fragments.

Ensure equipment to manage a failed intubation is available at all times.

Intubation via videolaryngoscopy ^[11][36]

• Description
  • A laryngoscope that allows indirect fiberoptic visualization of the glottic opening without head and neck manipulation ^[37]
  • Video from the distal end of the blade is delivered to an external video screen.
• Indications
  • Routine intubations ^[36][38]
  • Known or suspected difficult airway
  • Failed intubation with direct laryngoscopy
  • Teaching endotracheal intubation
• Technique is similar to direct laryngoscopy except for the following:
  • Sniffing position is not always required.
  • Use a matching rigid stylet OR mold a flexible stylet to match the curvature of the blade.
  • Insert the blade along the patient's tongue until the vocal cords are centered on the screen.
  • Confirm passage of the ET tube past the vocal cords on the screen.

Confirmation of ET tube placement ^[39][40]

• Direct visualization of endotracheal tube markers
  • Distal tube markers should be seen advancing past the vocal cords.
  • Proximal numbered tube markers should read approx. 21–23 cm at the patient's teeth.
• Auscultation: breath sounds audible over both lung fields
• Condensation: consistently visible in the tube during exhalation
• CO₂ detection: gold standard of successful endotracheal intubation ^[41]
  • Colorimetric capnometer: a qualitative CO₂ detector connected between the tube and the BMV equipment
    • A visual indicator changes color from purple to yellow upon contact with CO₂.
    • Consistent color changing with each breath > 3 times correlates with tracheal placement.
  • Capnometry: real-time quantitative EtCO₂ level displayed numerically on the monitor
  • If capnometry is inconclusive: bronchoscopy or esophageal detector device ^[40]
  • Capnography: real-time quantitative EtCO₂ displayed as a waveform
• Imaging (e.g., CXR)
  • CXR: The distal tip of the endotracheal or tracheal tube should be 2–6 cm above the carina (reposition if necessary).
  • Trained practitioners only: Ultrasound may be used to confirm tube position.

Intubation is an aerosol-generating procedure that carries a high risk of transmission of respiratory pathogens to healthcare workers. Appropriate PPE for all participating providers is essential. ^[42]

Timing of extubation

The decision of when to extubate varies and depends on the:

• Reason for intubation
• Patient's respiratory status and risk of post-extubation deterioration
• Health provider's advanced airway management skills, e.g., performing urgent reintubation

Extubation criteria

• Adequate spontaneous minute ventilation
• Presence of protective reflexes (swallowing and coughing reflex)
• Patient awake and following commands
• Adequate reversal of neuromuscular blockade
• Patient otherwise clinically stable
• No planned major diagnostic or therapeutic procedures

Consider ventilator weaning and/or a spontaneous breathing trial prior to extubation for patients who have received prolonged mechanical ventilation.

Procedure

• Preoxygenate with 100% FiO₂.
• Consider placing a bite block.
• Suction airways to minimize the risk of aspiration (e.g., of fluids, foreign material).
• Remove the securing mechanism and deflate the cuff.
• Remove the ET tube as the patient exhales.
• If respiratory failure occurs, reintubate and treat the underlying cause.

Do not extubate patients unless an adequately trained provider is available to reintubate if needed.

Complications

• Respiratory failure (i.e., failed extubation) due to: ^[46]
  • Respiratory muscle weakness
  • Decreased GCS
  • Excessive secretions
  • Postextubation laryngeal edema ^[47]
  • Inadequate cough
  • Cardiovascular instability
• Laryngospasm and bronchospasm
• Aspiration
• Negative pressure pulmonary edema
• Hypoventilation and upper airway obstruction
• Coughing and straining
• Vocal cord injury

Preparation checklist for intubation

• Preoxygenation
• Continuous cardiac monitoring
• Pulse oximetry
• IV access
• Intubation medications
• Saline flushes
• PPE
• Patient positioning
• Respiratory therapist at bedside

Equipment checklist for intubation

Ensure the following are accessible, tailored to the patient, and functioning:

• Laryngoscope and blades
• Appropriately sized ET tube
• Syringe for cuff inflation
• Lubricated stylet
• BMV device attached to oxygen
• Ventilator
• Equipment to secure ET tube in place
• Suction apparatus
• Difficult airway equipment

Postprocedure checklist for intubation

• Tube properly secured
• Cuff inflated
• Ventilator settings established
• Sedation started (see “Adjunctive care of ventilated patients”)
• CXR ordered
• ET tube placement confirmed on CXR
• Blood gas sent
• Procedure documented
• Clinical reassessment

Typical underlying causes

• Failure to successfully establish an airway (See “Difficult airway management.”)
• Hemodynamic and neurological effects of intubation, intubation medications, and/or positive pressure ventilation (See “High-risk conditions for intubation.”)
• Trauma from the passage or prolonged contact with the ET tube

Even successful intubations are very frequently associated with adverse events. Early identification of potential problems and modifications to standard techniques may reduce risks.

Early complications ^[48][49]

• Hypoxia
• Hypotension
• Bradycardia
• Respiratory acidosis
• Increased ICP
• Trauma
  • Dental damage
  • Tracheal perforation
  • Hemorrhage
• Pulmonary aspiration
• Laryngospasm
• Bronchospasm

Late complications ^[50]

• Vocal cord injuries
• Vocal cord granuloma

Complications of long-term intubation ^[51]

• Irritation and scarring of the trachea may occur, causing:
  • Laryngotracheal stenosis
    • An abnormal narrowing of the larynx (i.e., supraglottis, glottis, subglottis) or trachea.
    • Commonly manifests with hypoxia, respiratory distress, and stridor
    • Stridor may be inspiratory (supraglottic or glottic stenosis) or biphasic (glottic, subglottic, tracheal stenosis).
  • Tracheomalacia: softening of the tracheal cartilage, leading to collapse of the tracheal lumen and airway obstruction
• Clinical features: respiratory distress and stridor
• Diagnosis: confirmed with laryngoscopy or bronchoscopy
• Treatment: correction of the affected tracheal region via laser, stenting, or surgical removal, depending on the extent of injury

Some conditions can be exacerbated by standard intubation techniques. Modifications to the intubation process may be required to prevent deterioration.

Intubation of hemodynamically unstable patients

• Avoid further hypotension in already unstable patients, e.g., septic shock ^[49]
• Consider IV fluid bolus prior to induction, unless contraindicated (e.g., fluid overload).
• Choose etomidate or ketamine as the intubation induction agent.
• Administer bolus-dose vasopressors promptly to treat hypotension.
• See “Hemodynamic compromise in mechanically ventilated patients” for other troubleshooting measures.

Patients at risk of worsening hypertension or tachycardia

• Minimize reflex sympathetic effects of intubation in patients with:
  • Acute coronary syndrome
  • Acute aortic syndrome
  • ↑ ICP
• Consider pretreatment with fentanyl. ^[52]
• Plan intubation with highest chance of first-pass success to minimize laryngeal manipulation.

Intubation of patients with increased ICP ^{[1][9][11][52]}

• Avoid the following triggers of secondary brain injury:
  • Multiple attempts at intubation
  • Intubation induction agents that cause hypotension
  • Prolonged apnea time
• Prior to intubation:
  • Initiate ICP management measures while setting up for intubation.
  • Perform and document rapid baseline neurological examination (e.g., GCS, pupils, presence of lateralizing signs).
  • Consider pretreatment with fentanyl.
• Have the most experienced provider perform the intubation.
• Select an induction agent that does not affect ICP (e.g., etomidate).
• Postintubation
  • Recheck neurological examination after resolution of neuromuscular blockade.
  • Consider hyperventilation: See “Ventilation strategy for elevated ICP.”
  • Maintain sedation with agents/doses that ensure hemodynamic stability and have a rapid onset and offset to allow frequent neurological examination.

Intubation of agitated patients

• Patients with agitation secondary to conditions such as head injury, hypoxia, or cerebral hypoperfusion may not tolerate preoxygenation and intubation preparation.
• A modification known as delayed-sequence intubation, in which sedation (e.g., ketamine) is used to facilitate preoxygenation prior to intubation may be useful in these patients.

Approach

• Whenever possible, screen for red flags for a difficult airway during the preintubation assessment.
• Plan for difficult airway management in consultation with a specialist using techniques tailored to the patient.
• Obtain required equipment for difficult airway management and/or failed intubation, e.g.:
  • ET tubes of various sizes
  • Supraglottic airways
  • Intubation adjuncts, e.g., tracheal tube introducer
  • Emergency surgical airway equipment
  • Basic airway equipment and adjuncts, e.g., BMV, OPA, NPA
  • Forceps and suction devices

Call for help early (e.g., anesthesia or otolaryngology) if difficult intubation conditions are present. The most experienced provider should manage difficult airways.

Red flags for difficult airway

• Copious oral blood/secretions
• Upper airway distortion: e.g., edema, trauma, mass, anatomic variants
• Limited mouth opening: e.g, trismus, seizures, surgical hardware, oral neoplasms, anatomic variants
• Limited neck mobility: e.g., severe kyphosis, C-spine immobilization, ankylosing spondylitis, rheumatoid arthritis
• Obesity
• Previously documented difficult intubation, e.g, Cormack and Lehane grade III or IV

The LEMON assessment ^[1]

Identify difficult airway red flags prior to intubation with the following steps: ^[53]

• Look for concerning features: e.g., facial swelling or trauma, dentures, or C-spine immobilization.
• Evaluate: Use the 3-3-2 rule to assess mouth opening and larynx position. Intubation conditions are favorable if there are at least:
  • 3 fingerbreadths of mouth opening
  • 3 fingerbreadths of hyomental distance
  • 2 fingerbreadths of thyrohyoid distance
• Mallampati: Evaluate oral accessibility via visualization of the palate and throat with the Mallampati classification.
• Obstruction/obesity
  • Check for obstructive conditions (e.g., infection, angioedema, burns, or tumors) or clinical features of airway obstruction.
  • Evaluate body habitus.
• Neck mobility: Check for conditions requiring spinal precautions and evaluate range of motion.

Intubation adjuncts

These devices are used to facilitate difficult intubations. Some practitioners consider videolaryngoscopy an intubation adjunct, while others use is as a first-line technique for intubation.

• Tracheal tube introducer/gum-elastic bougie (GEB) ^[11][54]
  • A long, semirigid stylet used in conjunction with laryngoscopy to facilitate passage of the ET tube through the vocal cords ^[55]
  • The tip is slightly bent to allow passage under the epiglottis and to provide tactile feedback as it “clicks” over the tracheal rings.
  • Indication: a poor or completely obstructed view of the laryngeal inlet
• Flexible fiberoptic intubation ^[56]
  • A flexible fiberoptic laryngoscope or bronchoscope is used to visualize the glottis and guide an endotracheal tube into place, with the patient under minimal sedation and with no paralysis (i.e., awake intubation).
  • Local anesthetic is used to minimize airway sensation/reflexes and medication is used to reduce secretions.
  • Procedural sedation with ketamine or dexmedetomidine is often added.
  • Indications
    • Known or suspected difficult airway
    • Backup for failed intubation
• Others: e.g., lighted stylet, intubating SGAs, rigid bronchoscopy

Difficult airway management ^[57]

If Intubation is optional (e.g., planned surgery), consider alternatives to general anesthesia (e.g., local or regional anesthesia). ^[58]

Impending need for intubation

• Urgently consult an experienced airway specialist to:
  • Manage the airway
  • Determine if RSI is safe or unsafe
  • Evaluate the patient for awake flexible fiberoptic intubation
• Ensure the following are readily available:
  • Difficult airway equipment, including supraglottic airways and intubation adjuncts
  • Emergency surgical airway equipment ^[58][59]
• Optimize preoxygenation.

RSI can precipitate a cannot intubate-cannot ventilate (CICV) scenario in some patients with difficult airways. An awake flexible fiberoptic intubation may be the safest option. Urgently consult an airway specialist as soon as possible for patients with difficult airways requiring intubation.

Unavoidable immediate intubation ^[57]

• Consult local difficult intubation protocols and cognitive aids where available.
• Use a predefined sequence and combination of intubation adjuncts, e.g.:
  • Videolaryngoscopy to help facilitate visualization.
  • Gum elastic bougie to facilitate ET tube passage if the glottis is poorly visible.
• If intubation medications are used, choose a short-acting NMJ blocker (e.g., succinylcholine) if reversal agents for rocuronium are unavailable.
• For obese patients:
  • Use ramp position: Elevate shoulder and head so that the sternum is at the level of the external auditory meatus. ^[60]
  • Consider using a short handle if direct laryngoscopy is performed
• Manage as a failed intubation if unsuccessful.

Failed intubation ^[57][61]

• Declare a failed intubation.
• Urgently consult an airway specialist (e.g., anesthesia, ENT) to manage the airway.
• Perform BMV between attempts to maximize SpO₂ and safe apnea time for the following attempt.
• Consider alternative intubation adjuncts.
• Limit the number of intubation attempts. ^[61]
• Attempt ventilation through a supraglottic airway.
• If the ability to ventilate the patient is lost:
  • Declare a CICV scenario.
  • Maximize oxygenation, e.g., using HFNC, or apneic oxygenation
  • Prepare for surgical airway or cricothyrotomy.

Limit the number of intubation attempts to three, plus one additional attempt by a skilled practitioner. Repeated intubation attempts can cause bleeding, edema, and/or airway trauma that may prevent ventilation and/or delay the establishment of a definitive surgical airway. ^[57]

Cannot intubate, cannot ventilate (CICV) scenario ^[57][61]

• Definition: the inability to ventilate and/or maintain arterial oxygen saturation with either BMV or a supraglottic device in addition to the inability to intubate the trachea
• Causes: severe oropharyngeal edema, foreign body aspiration, severe oropharyngeal or nasal hemorrhage, facial trauma, acute epiglottitis
• Management: surgical airway or ECMO

Cannot intubate, cannot ventilate (CICV) is the most common indication for an emergency surgical airway. ^[11]

If initial attempts at intubation fail: ^[61]

Immediate steps

• Declare a failed intubation to alert other team members.
• Call for help.
• Begin BMV.

Assessment of BMV adequacy

• If BMV is adequate (cannot intubate-can ventilate), consider:
  • Further attempts using intubation adjuncts or modified techniques
  • Inserting a supraglottic airway
  • Awakening the patient (if under anesthesia)
• If BMV is not adequate: Attempt placement of a supraglottic airway and ventilation via the SGA.

Unsuccessful supraglottic airway (cannot intubate-cannot ventilate)

• Declare a CICV scenario to alert other team members to prepare for an emergency surgical airway.
• Attempt an alternative form of intubation while preparing.
• If unsuccessful, establish an emergency surgical airway.

Surgical airways may be placed in an emergency, if endotracheal or nasal intubation fails, as a planned intervention for patients with upper airway disease, or as part of the management of patients receiving longer-term ventilation.

General principles

• Typically used to treat CICV scenarios, e.g., after failed intubation.
• Can be considered early in difficult airway management if other options are contraindicated or too risky.
• Options
  • Surgical cricothyrotomy: definitive airway; can be performed by generalists (e.g., emergency physicians, trauma surgeons)
  • Needle cricothyrotomy paired with jet ventilation: can only be used as a temporizing measure (most often in young children)
  • Emergency tracheostomy: definitive airway; requires specialized skill to perform (e.g., ENT surgery)

Cricothyrotomy is the emergency surgical airway of choice because it is fast, simple, and has a high rate of successful placement. ^[11][62]

Cricothyrotomy ^[2][11][62]

See “Cricothyrotomy” for detailed procedural guidance and steps.

• Surgical cricothyrotomy
  • Performed either via open technique or percutaneously (Seldinger technique)
  • An ET tube or tracheostomy tube is placed into the trachea through the cricothyroid membrane via the skin and cervical fascia.
• Needle cricothyrotomy: typically performed in young children for whom surgical cricothyrotomy is contraindicated
  • Ventilation may be insufficient (e.g., impaired exhalation because of the small aperture of the needle)
  • Must be rapidly replaced with a definitive airway

Emergency tracheostomy

• May be performed in a CICV scenario by a trained practitioner
• Less commonly performed than a cricothyrotomy, as a tracheostomy is more complex, takes more time, and is associated with more bleeding ^[9]
• The procedure is similar to a planned tracheostomy.

Tracheostomy ^[11]

• Definition: a permanent or temporary opening (stoma) in the cervical trachea created through a surgical incision below the cricoid cartilage
• Indications
  • For emergency indications, same as for cricothyroidotomy
  • Long-term mechanical ventilation (> 3 weeks)
  • Malignancy
• Options
  • Percutaneous tracheostomy (typically under bronchoscopy guidance)
  • Open surgical tracheostomy
• Complications: See “Tracheostomy complications.”

Laryngectomy ^[63]

• Definition: the removal of all of the laryngeal structures, including the epiglottis and part of the upper trachea, with the trachea brought to the front of the neck to create a stoma
• Indications: laryngeal cancer
• Caution: As the upper airway is no longer connected to the trachea, patients with a laryngectomy cannot be oxygenated or intubated through the upper airway.

• Early complications ^[64]
  • Bleeding
  • Creation of a false lumen
  • Laceration of the back wall of the trachea
  • Damage to the surrounding structures: e.g., esophageal, mediastinal, or thyroid perforation, vocal cord injury, or recurrent laryngeal nerve injury
  • Pneumothorax
  • Subcutaneous emphysema
• Late complications
  • Dysphonia
  • Scarring
  • Stenosis
  • Tracheomalacia

Patients with surgical airways are vulnerable to tube displacement and occlusion secondary to secretions. Patients may rapidly deteriorate, necessitating that basic emergency maneuvers be performed prior to the arrival of an airway expert.

Tracheostomy complications ^[65][66]

• Apneic patients
  • Check pulse: If absent, start CPR.
  • If pulse present: Attempt ventilation over the surgical airway via BMV.
• Breathing patients: Apply oxygen to face and tracheostomy opening.
• All patients
  • Establish continuous cardiac monitoring, pulse oximetry, and capnometry.
  • Call for assistance from an airway expert (e.g., ENT surgeon, anesthesiologist).

Obstructed tracheostomy tube

Perform the following steps sequentially until the obstruction is relieved. Once the obstruction is relieved and the patient is adequately ventilated, continue the ABCDE assessment.

• Remove the speaking valve, cap, and/or inner cannula.
• Attempt to pass a suction catheter and perform tracheal suctioning.
• Deflate the tracheal cuff and assess for air movement.
• If the blockage cannot be relieved, remove the tracheostomy tube.
• If ventilation is still inadequate, begin BMV.
  • Oral: Cover stoma and ventilate with a face mask and/or adjuncts (e.g., oral airway, LMA).
  • Stoma: Close mouth and nose and ventilate through the stoma with a pediatric mask or externally applied LMA.
• Consider tracheal intubation.

Displaced tracheostomy tube

• Remove displaced tracheostomy tubes immediately.
• Involve surgical team for replacement of newly established tracheostomies.
• Confirm correct placement of all replaced tubes, ideally with EtCO₂.

Bleeding around or from tracheostomy tube

• All bleeding should be evaluated by a surgical specialist.
• Localized surface bleeding: Consider tranexamic acid or epinephrine-soaked gauze.
• Blood within the tube
  • May indicate a tracheoinnominate fistula
  • Consider hyperinflation of the tracheostomy cuff as a temporizing measure.

Remove obstructed or displaced tracheostomy tubes as soon as they are recognized. ^[66]

Patient with laryngectomy ^[65]

The approach to airway management is similar to that of tracheostomies, but no upper airway maneuvers are attempted. Patients with long-term laryngectomies typically no longer have a tube in situ.

• To improve oxygenation, attach a high-flow oxygen device over the stoma site.
• To ventilate the patient, apply a pediatric mask or LMA after removing the stoma cover.
• If noninvasive ventilation fails, consider intubation of the stoma with 6.0 or smaller ETT.

Patients with a laryngectomy do not have a patent upper airway; oral or nasal attempts at oxygenation or intubation will be unsuccessful!