What is the recommended procedure for intubation in patients requiring tracheal intubation?

Intubation Procedure in Critically Ill Adults

Primary Technique: Rapid Sequence Intubation

Rapid sequence induction (RSI) with endotracheal intubation via the oral route is the gold standard for emergency airway management in critically ill adults. 1, 2

Pre-Intubation Preparation

Preoxygenation is mandatory and should be performed with noninvasive ventilation rather than simple facemask oxygen, as this prevents hypoxemia during the procedure. 3

• Position the patient with head elevation (reverse Trendelenburg or ramped position) if hemodynamically stable 4, 5
• Apply manual in-line stabilization if cervical spine injury is suspected, rather than relying solely on cervical collar 1
• Ensure immediate availability of vasopressors for bolus and infusion, as hemodynamic collapse is common during induction 4
• Have rescue airway equipment at bedside including second-generation supraglottic airway device and surgical cricothyroidotomy kit 4

Medication Selection

The recommended initial dose of rocuronium for intubation is 0.6 mg/kg, which provides intubation conditions in a median time of 1 minute. 2

• For rapid sequence intubation specifically, rocuronium 0.6-1.2 mg/kg provides excellent intubating conditions in less than 2 minutes 2
• Ketamine (1-2 mg/kg) should be considered as the induction agent in shock states as it provides vasopressor effects 4
• Etomidate (0.3 mg/kg) combined with succinylcholine (1.5 mg/kg) produces superior laryngoscopy conditions compared to etomidate alone 6
• Full neuromuscular blockade is optimal in most critically ill patients and increases success of all airway techniques including rescue procedures 4

Laryngoscopy Technique

Videolaryngoscopy should be used as the first-line technique if available and the operator is experienced, as it facilitates successful first-attempt intubation and may prevent esophageal intubation. 1, 3, 7

• Use of a stylet or bougie is superior to endotracheal tube alone and comparable between the two devices 3
• For patients with Cormack-Lehane grade 3a view (epiglottis can be lifted), a bougie significantly improves success 4
• Administer positive pressure ventilation between induction and laryngoscopy to prevent hypoxemia 3

Post-Intubation Priorities

Waveform capnography must be used immediately to verify tube placement and monitor ventilation adequacy, as failure to use capnography contributes to >70% of ICU airway-related deaths. 1, 8

• Target tidal volumes of 6-7 mL/kg to avoid excessive ventilation and gastric insufflation 1
• Maintain normoventilation (PaCO₂ 35-40 mmHg) unless signs of cerebral herniation are present 1
• Consider recruitment maneuvers (inspiratory pressure 30-40 cm H₂O for 25-30 seconds) in hypoxic patients if hemodynamically stable 4

Failed Intubation Algorithm

Failed intubation occurs in 10-30% of critically ill patients and must be anticipated with a structured rescue plan. 4

Plan B/C: Rescue Oxygenation

• After one failed intubation attempt, immediately obtain the front-of-neck airway (FONA) equipment 4
• Attempt rescue oxygenation with second-generation supraglottic airway device (ProSeal LMA has highest seal pressure, followed by LMA Supreme and i-gel) 4
• Maximum of three attempts with SGA or facemask ventilation before declaring failure 4
• After one failed attempt at SGA/facemask oxygenation, open the FONA set 4

The Vortex approach is recommended, which defines alternating attempts at intubation, SGA placement, and facemask ventilation, with immediate transition to FONA if all fail. 4

Plan D: Cannot Intubate, Cannot Oxygenate (CICO)

Scalpel cricothyroidotomy is the recommended FONA technique, as it is fast, reliable, and provides a definitive airway with the ability to apply PEEP. 4

• Use maximum neck extension with horizontal incision using size 10 or 20 scalpel blade 4
• Insert bougie as guide for 5.0-6.0 mm tracheal tube 4
• Transtracheal jet ventilation via narrow-bore cannula is NOT recommended due to high failure rates, barotrauma risk, and inability to provide PEEP in critically ill patients 4

Special Populations

Obesity (BMI >30 kg/m²)

Obese patients have twice the complication rate of non-obese patients in ICU, with four-fold increased risk if BMI >40 kg/m². 4

• Desaturation occurs with exceptional speed and severity 4
• Obesity increases difficulty of facemask ventilation, SGA placement, intubation, and FONA 4
• Undiagnosed obstructive sleep apnea further increases intubation and extubation risks 4

Difficult Airway

The most experienced available operator must manage patients with known difficult airway combined with impaired gas exchange. 4

• Awake intubation should only be attempted by highly skilled clinicians with careful head-up positioning, minimal sedation, adequate topical anesthesia, active preoxygenation (e.g., high-flow nasal oxygen), and clear failure plan 4
• Intravenous induction with "double setup" is recommended when difficult intubation is anticipated: mark the cricothyroid membrane before induction, with one operator attempting intubation while a second is primed to perform FONA 4
• Inhalational techniques are NOT recommended in critically ill patients due to slow induction complicated by obstruction, hypoxemia, and hypercarbia 4

Critical Pitfalls to Avoid

• Never delay intubation to obtain complete vital signs when airway protection is needed - airway obstruction, altered consciousness (GCS ≤8), hypoventilation, or hypoxemia require immediate intervention regardless of blood pressure status 8
• Never administer fluid bolus before induction expecting it to prevent hypotension - this strategy has been proven ineffective in randomized trials 3
• Never use first-generation supraglottic airways for rescue - their low seal pressures cannot adequately ventilate poorly compliant lungs and increase gastric inflation risk 4
• Never delay progression to FONA - psychological reluctance to perform FONA is a greater cause of morbidity than complications of the procedure itself 4