What Is Intubation?

Intubation is the clinical procedure of inserting a tube into a patient's airway to establish or maintain ventilation, deliver anesthetic agents, protect the lungs from aspiration, or provide a conduit for suctioning. In medical practice, the term most commonly refers to endotracheal intubation, in which a flexible plastic tube is passed through the mouth or nose, through the vocal cords, and into the trachea. Once positioned, the tube is connected to a ventilator or manual resuscitation device to deliver controlled breaths. Intubation is performed across emergency, intensive care, and surgical settings and is a foundational skill in airway management.

The procedure intersects the respiratory system at the level of the upper airway and trachea. Engineering contributions to intubation include the development of video laryngoscopes, optical fiber guidance systems, cuffed tube designs that improve seal reliability, and sensor systems for automated confirmation of correct tube placement.

Procedure and Techniques

In orotracheal intubation, the clinician uses a laryngoscope to visualize the vocal cords and pass the endotracheal tube through the glottis into the trachea, as described in endotracheal intubation techniques and clinical guidance. Video laryngoscopy, in which a camera at the blade tip projects an image to an external monitor, improves glottic visualization in patients with difficult airways and has become widely adopted in both elective and emergency settings. Nasotracheal intubation, passing the tube through the nasal passage, is used when oral access is limited. Fiberoptic bronchoscopy-guided intubation provides direct visual guidance through the tube itself, suitable for anticipated difficult airways or awake intubation under local anesthesia. Confirmation of tracheal placement relies primarily on measurement of exhaled carbon dioxide (end-tidal CO2), which is the accepted standard for verifying that the tube is in the airway rather than the esophagus.

Tube Design and Cuff Mechanics

Endotracheal tubes are manufactured with a low-pressure, high-volume inflatable cuff near the distal tip that seals against the tracheal wall when inflated. Maintaining cuff pressure within the range of 20 to 30 centimeters of water prevents air leak around the tube during positive-pressure ventilation while avoiding ischemic damage to the tracheal mucosa from excessive compression. Tube materials are chosen to minimize tissue reactivity and bacterial adherence; subglottic secretion drainage channels above the cuff reduce aspiration of oropharyngeal secretions and lower the incidence of ventilator-associated pneumonia. Specialized tubes for specific procedures include armored tubes resistant to kinking during head and neck surgery, double-lumen tubes for one-lung ventilation in thoracic procedures, and endobronchial blockers for selective lobar occlusion.

Connection to Mechanical Ventilation

Once an endotracheal tube is in place, the patient's airway is isolated and the tube connects to a mechanical ventilator, which delivers gas at controlled tidal volumes, pressures, and flow rates as described in overviews of mechanical ventilation in critical care. The ventilator settings are adjusted for the patient's lung compliance, respiratory drive, and gas exchange requirements. Prolonged intubation, lasting more than a few days, carries risks including tube occlusion, vocal cord injury, and subglottic stenosis, motivating protocols for early weaning and extubation assessment. For patients requiring long-term ventilation, tracheostomy provides a more stable airway interface with lower risk of oral and laryngeal complications.

Applications

Intubation has applications across a range of clinical settings, including:

• Emergency airway management in trauma, cardiac arrest, and respiratory failure
• General anesthesia induction for surgical procedures requiring airway protection
• Intensive care unit management of mechanically ventilated patients
• Neonatal and pediatric care for respiratory distress and congenital airway conditions
• Pre-hospital transport for patients with compromised airway patency