What is the recommended procedure for patient intubation?

Patient Intubation: Recommended Procedure

Intubation should be performed by the most experienced available operator using videolaryngoscopy when available, with modified rapid sequence induction (RSI) including full neuromuscular blockade after adequate preoxygenation, limiting attempts to a maximum of three laryngoscopy insertions. 1, 2

Pre-Intubation Assessment and Preparation

Risk Stratification

• Calculate the MACOCHA score to identify patients at risk for difficult intubation (score ≥3 indicates high risk with 73-76% sensitivity): 2, 3

  • Mallampati III or IV (5 points)
  • Obstructive sleep apnea (2 points)
  • Limited cervical spine mobility (1 point)
  • Mouth opening <3 cm (1 point)
  • Coma (1 point)
  • Hypoxemia (1 point)
  • Untrained operator (1 point)

• For patients with MACOCHA score ≥3, ensure difficult airway trolley and bronchoscope are immediately available. 2

Equipment Preparation

• Verify all equipment is functional before induction: laryngoscope (preferably videolaryngoscope), endotracheal tubes of multiple sizes, stylet/bougie, suction device, ventilators, standard monitoring, venous access, vasoactive drugs, and waveform capnography. 1, 2

• For high-risk patients, prepare backup devices: disposable videolaryngoscope blades, second-generation supraglottic airway device, and emergency cricothyroidotomy kit. 1

• Install high-efficiency breathing circuit filters between the mask and breathing circuit, and at the proximal end of the breathing circuit. 1

Team Configuration

• Intubation should be performed by an experienced anesthesiologist assisted by another clinician (anesthesiologist or intensive care physician) to minimize attempts and aerosol production. 1

• In difficult airway cases, the most experienced available operator must manage the case; ideally bring the team to the patient in a critical care environment rather than transferring the patient. 1

Preoxygenation Strategy

• Position the patient head-up (ramped position for obese patients) with neck extended unless contraindicated, to reduce airway swelling and improve laryngoscopic view. 1, 2

• Administer high-flow oxygen to achieve maximal oxygen saturation before induction, combining inspiratory support with positive end-expiratory pressure for hypoxemic patients. 2, 3, 4

• Consider apneic oxygenation using high-flow nasal oxygen during the intubation procedure to prevent desaturation. 3, 4

Induction and Intubation Technique

Modified Rapid Sequence Induction

• For patients with normal airways, use modified rapid sequence induction with sufficient muscle paralysis achieved after loss of consciousness. 1, 5

• Administer neuromuscular blocking agents (NMBAs) as they significantly reduce intubation complications; rocuronium is preferred over succinylcholine due to fewer side effects. 2, 6

  • Rocuronium dose: 0.6 mg/kg for routine intubation, 0.6-1.2 mg/kg for rapid sequence intubation 6
  • Avoid succinylcholine if >24 hours have passed in envenoming cases due to hyperkalemia risk 5

• Choose induction drugs based on hemodynamic considerations: midazolam 2-5 mg with etomidate 10-20 mg, or propofol if hemodynamically stable. 1

Laryngoscopy Approach

• Use videolaryngoscopy as first-line when available and the operator is experienced, as it increases distance from the patient's airway and improves success rates. 1, 2, 3

• Oral intubation is preferred over nasal; when using direct laryngoscopy, minimize patient coughing and bucking. 1

• Limit attempts to a maximum of three laryngoscopy insertions (each blade entry constitutes one attempt); declare "failed intubation" after three attempts and move to rescue strategies. 2

• Use a bougie during direct laryngoscopy, particularly in patients with cervical spine precautions where manual-in-line stabilization worsens laryngeal view. 1

Special Circumstances

Difficult Airway Management

• Awake intubation should only be attempted by suitably skilled clinicians with careful head-up positioning, minimal sedation, adequate topical anesthesia (2% lidocaine 2-3 mL or 1% lidocaine 4-6 mL), active preoxygenation, and a clear plan for failure. 1

• Do not use inhalational techniques for difficult airway management in critically ill patients as this causes slow induction with upper airway obstruction, hypoxemia, and hypercarbia. 1

• When difficult intubation is anticipated, use "double set-up" technique: identify and mark the cricothyroid membrane before induction, attempt intubation with one operator while a second operator is primed to perform front-of-neck access (FONA) if required. 1

Obesity

• Obese patients (BMI >30 kg/m²) have twice the complication risk; BMI >40 kg/m² increases risk four-fold. 1

• For obese patients with impalpable cricothyroid membrane, use ultrasound for pre-induction identification. 1

• Provide thorough pre- and peroxygenation head-up with CPAP/NIV or high-flow nasal oxygen; use ramped position to increase intubation success. 1

• If intubation fails in obese patients, do not attempt multiple intubations, supraglottic airway rescue, or facemask ventilation; proceed promptly to FONA with scalpel technique using vertical incision. 1

Cervical Spine Injury

• Perform RSI using manual-in-line stabilization with removal of at least the anterior cervical collar to facilitate mouth opening and cricoid force application. 1

• Use videolaryngoscopy with low threshold in cervical spine patients as it increases success with minimal cervical movement. 1

Post-Intubation Management

Confirmation and Monitoring

• Never assume tracheal placement without capnography confirmation; verify with appropriate capnogram waveform and stable or improving oxygenation. 1, 2

• Watch for "airway red flags": absence or change of capnograph waveform, increasing airway pressure, reducing tidal volume, or inability to pass a suction catheter. 2

• Remove outer gloves immediately after intubation completion and apply fresh gloves. 1

Ventilation Strategy

• Use closed airway suction system when available to reduce viral aerosol production; if unavailable, minimize suctions using non-closed system. 1

• Monitor for complications including hypotension, desaturation, and tube displacement. 2, 4

Common Pitfalls to Avoid

• Do not perform more than three laryngoscopy attempts as this increases complications and exposes patients to higher 28-day mortality risk. 2, 4

• Be aware that apnea oxygenation time is often extremely short in critically ill patients; great effort is needed to avoid severe hypoxemia. 1

• In COVID-19 or infectious patients, intubation is an aerosol-producing high-risk procedure requiring full PPE: test-fit N95 mask, protective whole-body garment, two layers of gloves, goggles or face shield, and waterproof gown. 1

• Consider intubation sooner than customary in burn patients to allow sufficient time for infection control precautions; intubation in awake patients may cause agitation and coughing that compromises safety. 1