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How To Insert an Esophageal-Tracheal Double Lumen Tube (Combitube) or a King Laryngeal Tube


Bradley Chappell

, DO. MHA, Harbor-UCLA Medical Center

Reviewed/Revised Feb 2023
Topic Resources

The esophageal-tracheal double lumen tube (Combitube) and the King laryngeal tube are supraglottic airway devices (also called retroglottic airway devices).

The esophageal-tracheal double lumen tube (Combitube) and the King laryngeal tube are twin-lumen tubes that have fundamental similarities:

  • A large proximal balloon cuff seals the hypopharynx

  • A ventilating, proximal lumen terminates at side ports overlying the laryngeal inlet

  • A distal lumen and its smaller balloon cuff terminate in and seal the upper esophagus (in > 90% of insertions)

Supraglottic airways are useful for providing rescue ventilation to unconscious patients or patients without a gag reflex and are also used in some elective settings.

The esophageal-tracheal double lumen tube and King laryngeal tube have some advantages over other methods of ventilation:

Indications for Combitube or King Laryngeal Tube Insertion

Contraindications to Combitube or King Laryngeal Tube Insertion

Absolute contraindications

  • There is no medical contraindication to providing ventilatory support to a patient; however, a legal contraindication (do-not-resuscitate order or specific advance directive) may be in force

  • Restricted mouth opening that blocks tube insertion (nasotracheal intubation or a surgical airway would be indicated in this case)

  • Impassable upper airway obstruction (surgical airway would be indicated in this case)

Relative contraindications

  • Consciousness or presence of a gag reflex

  • Hypopharyngeal or esophageal abnormalities or trauma (which increase the risk of further local damage by a supraglottic airway)

  • Combitube is not recommended for patients < 4 feet tall

Complications of Combitube or King Laryngeal Tube Insertion

Complications include

  • Vomiting and aspiration during tube insertion or after placement in patients who regain a gag reflex

  • Dental or oropharyngeal soft tissue trauma during tube insertion

  • Tongue edema due to prolonged placement or balloon overinflation

Equipment for Combitube or King Laryngeal Tube Insertion

Additional Considerations for Combitube or King Laryngeal Tube Insertion

  • The balloon cuffs of the Combitube are inflated individually. The balloon cuffs of the King laryngeal tube share a single pilot tube and inflate simultaneously.

  • An estimated 1 to 5% of Combitube insertions enter the trachea; in these cases, if the misplacement is recognized, the cuffed distal lumen can be used to function as an endotracheal tube. Probably at least 10% of insertions done with newer King laryngeal tubes enter the trachea; ventilation may be possible through the distal lumen in these cases. Older King tubes are contoured such that virtually all insertions enter the esophagus.

  • The ventilating lumen of the King tube is suitable for stylet insertion to facilitate conversion of the King tube to an endotracheal tube. However, visualization of the glottis through this lumen is often impossible.

Relevant Anatomy for Combitube or King Laryngeal Tube Insertion

  • Aligning the ear with the sternal notch may help open the upper airway and establishes the best position to view the airway if endotracheal intubation becomes necessary.

  • The degree of head elevation that best aligns the ear and sternal notch varies depending on the patient's age and body habitus.

Positioning for Combitube or King Laryngeal Tube Insertion

  • Optimal position for tube insertion is the sniffing position, but Combitube or King tube insertion can be done with the patient’s neck in a neutral position.

  • The operator stands at the head of the stretcher.

  • An assistant may stand at the side.

The sniffing position is used only in the absence of cervical spine injury:

  • Position the patient supine on the stretcher.

  • Place folded towels or other materials under the head, neck, and shoulders, flexing the neck so as to elevate the head until the external auditory meatus lies in the same horizontal plane as the sternal notch. Then, tilt the head so that the face aligns on a parallel horizontal plane; this second plane will be above the first. In patients with obesity, many folded towels or a commercial ramp device may be needed to sufficiently elevate the shoulders and neck (see figure head and neck positioning to open the airway Head and neck positioning to open the airway Head and neck positioning to open the airway ).

Head and neck positioning to open the airway

A: The head is flat on the stretcher; the airway is constricted. B: Establishing the sniffing position, the ear and sternal notch are aligned, with the face parallel to the ceiling, opening the airway. Adapted from Levitan RM, Kinkle WC: The Airway Cam Pocket Guide to Intubation, ed. 2. Wayne (PA), Airway Cam Technologies, 2007.

Head and neck positioning to open the airway

If cervical spine injury is a possibility:

Step-by-Step Description of Combitube or King Laryngeal Tube Insertion

How To Insert an Esophageal-Tracheal Combitube
King Tube Placement
  • Clear the oropharynx, as necessary, of obstructing secretions, vomitus, or foreign material.

  • Select the appropriately sized Combitube or King laryngeal tube and note the appropriate cuff inflation volume for King tubes. This information is on the tube packaging and the cuff of the tube itself.

  • Inflate and deflate the cuffs to check that there are no leaks.

  • Apply a small amount of sterile, water-soluble lubricant to the deflated cuffs.

  • Lift the chin and tongue with your non-dominant hand. Grasp the tongue and chin between your thumb inside the mouth and your fingers on the underside of the chin, and lift up.

  • Insert the Combitube or King tube into the mouth. Insert the Combitube with a midline orientation. Insert the King tube initially at the corner of the mouth 45 to 90 degrees of rotation off-center, and then rotate it to midline position when the tip of the tube is past the tongue. Do not force either tube; you may cause soft tissue damage. If resistance is encountered, pull back somewhat and re-advance the tube, trying to follow the posterior pharyngeal wall. You may need to remove the tube, alter its curvature, and then reinsert it. At the proper distance of insertion (as confirmed by markings on the tube), the proximal (ventilating) lumen will open over the laryngeal opening, and the distal lumen will have entered the esophagus (in most cases).

  • Release your hand from the tube before inflating the cuffs.

  • Inflate the cuffs. When using a King laryngeal tube, use the manufacturer’s recommended volume. When using a Combitube, inflate the distal balloon first using 10 to 15 mL, then inflate the proximal (pharyngeal, blue) balloon using 50 to 85 mL.

  • Connect a bag-valve apparatus to the ventilating lumen (on the Combitube, the blue [pharyngeal] lumen).

  • Begin ventilation (8 to 10 breaths/minute, each about 500 mL and lasting about 1 second).

  • Assess lung ventilation by auscultation and chest rise. Check end-tidal carbon dioxide to confirm tube placement. Auscultation for Combitube placement is often difficult and unreliable, so rely more on capnometry. However, during cardiac arrest, capnometry may not reliably indicate proper tube placement.

  • If assessment suggests inadvertent tracheal placement of a Combitube, try ventilating through the distal cuff.

Aftercare for Combitube or King Laryngeal Tube Insertion

  • Fix the tube in place with tape or ties, as appropriate.

  • The Combitube or King laryngeal tube, after several hours at most, must be removed or be replaced by a definitive airway, such as an endotracheal tube or surgical airway (cricothyrotomy or tracheostomy).

Warnings and Common Errors for Combitube or King Laryngeal Tube Insertion

  • In about 5% of Combitube insertions, the distal tube will enter the trachea; in this case, ventilation can be done through the distal tube. In up to 10% of insertions of newer King tubes, the distal tube will enter the trachea; adequate ventilation may be possible through the distal tube.

  • Generally, supraglottic airways should be inserted only in patients who are unresponsive; otherwise, aspiration is a risk. Do not allow a patient to awaken during insertion or ventilation with a supraglottic airway. If necessary, prevent the patient from waking up or gagging (using paralytics, adequate analgesia, and sedation), or remove the airway as clinically indicated.

  • Placing the dual lumen tubes too deeply may cause the balloon to obstruct the tracheal opening and inhibit ventilation. Obstruction can be remedied by pulling the airway back a few centimeters.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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