What are the indications for intubation?

Indications for Intubation

Intubate immediately for inability to ventilate an unconscious patient with bag-mask, absence of airway protective reflexes (GCS <8), or imminent respiratory arrest. 1, 2

Primary Respiratory Indications

Hypoxemic Respiratory Failure

• PaO₂/FiO₂ ratio <150 mmHg with acute respiratory distress requires intubation 2
• Failure to improve after 2 hours of high-flow oxygen therapy or noninvasive ventilation (NIV) mandates intubation 2, 3
• Respiratory rate >30 breaths/minute with acute respiratory distress that does not respond to supplemental oxygen is an indication for intubation 2, 3
• Refractory hypoxemia despite optimal supplemental oxygen therapy requires definitive airway management 3

Hypercapnic Respiratory Failure

• pH <7.25 warrants consideration of intubation; pH <7.15 after initial resuscitation and controlled oxygen is a strong indication 1, 2
• Progressive hypercapnia with worsening acidosis despite NIV requires intubation 2, 3
• In COPD exacerbations specifically, persisting or worsening acidosis despite optimized NIV delivery indicates NIV failure and need for intubation 1

Imminent Respiratory Collapse

• Apneic episodes or imminent respiratory arrest require immediate intubation 1, 2
• Physical exhaustion with inability to sustain respiratory effort mandates intubation 2
• Gasping respirations indicate need for immediate intubation 1

Airway Protection Indications

Depressed Consciousness

• Glasgow Coma Score <8 indicates inability to protect the airway and is an indication for intubation 1, 2, 3
• Declining consciousness with inability to maintain patent airway requires intubation 2, 3
• Depressed consciousness preventing adequate airway protection mandates intubation 2

Airway Obstruction and Aspiration Risk

• Upper airway obstruction with dyspnea, desaturation, or stridor (from facial/thermal burns, anaphylaxis, angioedema) requires intubation 2, 3
• Pooling secretions with inability to manage oropharyngeal accumulation indicates need for intubation 2, 3
• Recent aspiration or high aspiration risk warrants intubation 2

Hemodynamic Indications

• Cardiogenic shock where mechanical ventilation may improve outcomes is an indication for intubation 2
• Severe bradycardia or heart block causing hemodynamic compromise may require intubation 2
• Cardiac-related pulmonary edema deteriorating despite optimal pharmacological treatment and NIV requires intubation 3

Neurological Indications

• Large territorial stroke with declining consciousness and inability to maintain airway patency requires intubation 2, 3
• Generalized tonic-clonic seizures requiring airway control are an indication for intubation 2

Special Clinical Scenarios

• Cervical spine injury with severe respiratory distress requires intubation using rapid sequence intubation with manual in-line stabilization 2
• Severe asthma with apnea, coma, persistent or increasing hypercapnia, exhaustion, or severe depression of mental status requires intubation 3

Critical Pitfalls to Avoid

• Do not delay intubation while waiting for arterial blood gas or radiography if clear clinical signs of respiratory failure are present 3
• Do not persist with ineffective NIV when pH is worsening or patient distress is increasing—this delays necessary intubation and increases risk of cardiorespiratory arrest 1
• In cardiac arrest, the incidence of complications from intubation by inexperienced providers is unacceptably high; frequent experience or retraining is essential 1
• Intubation in critically ill patients carries high risk: 28% experience severe complications including severe hypoxemia (26%), hemodynamic collapse (25%), and cardiac arrest (2%) 4
• Acute respiratory failure and shock as indications for intubation are independent risk factors for complications—prepare meticulously with experienced operators 4

Preparation Requirements

When intubation is indicated, ensure immediate availability of: laryngoscope (consider videolaryngoscopy if operator is skilled), endotracheal tubes, bougie/stylet, suction, backup airway devices (second-generation supraglottic airways), and waveform capnography for mandatory confirmation of tube placement 1, 2