Cuffed Endotracheal Tube (ETT)

What It Is

A cuffed endotracheal tube is a single-use, disposable, transparent PVC tube inserted through the mouth (orotracheal) or nose (nasotracheal) into the mid-trachea. Key features include:

Universal 15-mm proximal adapter — connects to ventilating circuits
High-volume, low-pressure (HVLP) cuff — inflated with air to seal the trachea
Beveled tip — eases passage through the vocal cords
Murphy eye — a side hole near the distal tip that maintains airflow if the main lumen is occluded
Pilot balloon with one-way valve — allows cuff inflation monitoring
Depth markings (cm) — to confirm correct placement depth

Standard sizes: 8.0–8.5 mm ID for adult males; 7.5–8.0 mm ID for adult females.

Indications

Absolute Indications

Clinical Scenario	Rationale
Full stomach / aspiration risk (trauma, emergency, GERD, pregnancy)	Cuff provides maximal protection against pulmonary aspiration
Critically ill patients	Airway protection and ventilatory support
Respiratory failure / poor lung compliance	Allows positive pressure ventilation (PPV) at higher airway pressures than a mask or supraglottic airway (SGA) can achieve
Lung isolation required (e.g., thoracic surgery)	Double-lumen ETT placed for one-lung ventilation
ENT/head-neck surgery where SGA would obstruct the surgical field	Direct tracheal access required
Anticipated prolonged post-operative mechanical ventilation	Definitive, stable airway
Failed SGA placement	Rescue airway
Cardiac/respiratory arrest	Airway control, allows high-quality PPV

Relative / Other Indications

Requirement for neuromuscular blocking drugs (surgery)
Patient positioning precluding safe SGA use (prone, lateral, remote from anesthesia provider)
Predicted difficult airway — awake intubation preferred
Prolonged surgical procedures
Decreased level of consciousness with impaired gag/cough reflex (e.g., toxicology, overdose — protect airway before gastric lavage)
Inhalation injury / airway burns — edema can rapidly close the airway
Airway foreign body, massive hemoptysis, severe pulmonary edema

Contraindications

There are no absolute contraindications to orotracheal intubation when the airway must be secured urgently. However, certain situations require a modified or alternative approach:

Situation	Preferred Alternative
Suspected cervical spine instability	In-line stabilization technique; video laryngoscopy; awake fiberoptic intubation
Anticipated difficult/impossible intubation (e.g., severe trismus, supraglottic mass, angioedema, Ludwig's angina)	Awake fiberoptic intubation (FOI); surgical airway (cricothyrotomy/tracheostomy)
Fixed stenotic laryngotracheal lesion	Cannot pass ETT without dilation; tracheostomy preferred
Significant airway bleeding	Obscures laryngoscopic visualization; FOI contraindicated; surgical airway may be needed
Uncooperative/combative patient	Awake FOI contraindicated; RSI with video laryngoscopy preferred
Epiglottitis (pediatric)	Avoid instrumentation in ED; secure in OR with ENT backup
Laryngeal fracture	Blind/oral intubation may worsen injury; tracheostomy preferred

Cuff Considerations

Inflate cuff to minimum volume to achieve a seal (no audible air leak)
Target cuff pressure: < 25 cm H₂O — excess pressure causes tracheal mucosal ischemia, recurrent laryngeal nerve palsy, and sore throat
When nitrous oxide (N₂O) is used, monitor cuff pressure intraoperatively — N₂O diffuses into the cuff, raising pressure to dangerous levels

Confirming Correct Placement

After insertion, confirm by:

Direct visualization of ETT passing through the vocal cords
End-tidal CO₂ (capnography) — gold standard; waveform or reading >30 mmHg confirms tracheal placement
Colorimetric CO₂ detector — changes yellow → purple on exhalation
Bilateral chest auscultation (and absence of gastric sounds over epigastrium)
Chest X-ray — confirms ETT tip position (should be 3–5 cm above carina)
Ultrasound — ETT visualized within tracheal lumen; "double-track sign" suggests esophageal placement

Key Complications

Complication	Mechanism
Esophageal intubation	Most critical error; leads to hypoxia/death if undetected
Right mainstem intubation	Tube advanced too deep; left lung collapse
Tracheal mucosal injury	Excessive cuff pressure
Postextubation stridor	Subglottic edema; risk ↑ with large ETT, prolonged intubation, multiple attempts
Vocal cord injury	Traumatic laryngoscopy or cuff overinflation
Ventilator-associated pneumonia (VAP)	Biofilm on ETT; aspiration of subglottic secretions around cuff
Accidental extubation / displacement	Loss of airway

Sources: Miller's Anesthesia 10e; Tintinalli's Emergency Medicine; Cummings Otolaryngology; Barash Clinical Anesthesia 9e

This is a shared conversation. Sign in to Orris to start your own chat.