Cricothyrotomy

Keyword

Cricothyrotomy

Definition

A procedure that involves placing a tube through an incision in the cricothyroid membrane to establish an airway for oxygenation and ventilation

Indications

When the “can’t intubate, can’t ventilate” scenario presents

Techniques

There are two most common techniques for performing a cricothyrotomy

1. Percutaneous dilational cricothyrotomy
   • Because of the location of the cricothyroid artery and the proximity of the CTM to the vocal folds, puncture or incision of the CTM(cricothyroid membrane) should be made in the lower third of the membrane and directed posteriorly
   • Sequence
     • The patient’s neck is extended, and the cricothyroid groove is identified.
     • A 1- to 1.5-cm vertical incision is made through the skin overlying the CTM.
     • An 18-gauge needle-catheter attached to a fluid-filled syringe is passed through the incision at a 45-degree angle in the caudal direction with continuous aspiration.
     • Aspiration of free air confirms passage through the CTM.
     • The catheter is advanced over the needle into the trachea.
     • The needle is removed, and the catheter is left in place.
     • The guidewire is inserted caudally to a depth of approximately 2 to 3 cm.
     • The catheter is removed, and the curved dilator with the airway cannula is threaded over the guidewire.
     • The dilator and cannula unit is advanced through the CTM while aintaining control of the guidewire.
     • The dilator and guidewire are removed together while the cannula remains in place.
     • The cuff is inflated, and ventilation is attempted.
     • Proper placement is confirmed by capnography, and the airway cannula is secured in place.

1. Surgical cricothyrotomy
   • Sequence
     • Step 1: Extend the head and neck, and identify and immobilize the cricothyroid membrane. (Make an initial vertical incision if identification is not possible.)
     • Step 2: Make a horizontal stab incision through the skin and cricothyroid membrane. Leave the blade in place until the tracheal hook is in position (step 3).
     • Step 3: Apply caudal and outward traction on the cricoid cartilage with the tracheal hook; remove the scalpel.
     • Step 4: Insert the tube, and inflate the cuff.
     • Step 5: Ventilate with a low-pressure source.
     • Step 6: Confirm pulmonary ventilation.

Contraindications

• Children younger than 6 years of age ; the cricoid cartilage is the narrowest portion of the airway and the isthmus of the thyroid gland typically reaches the level of the CTM; therefore cricothyrotomy is contraindicated.
• Laryngeal fractures
• Laryngeal neoplasm
• subglottic stenosis
• Coagulopathy
• Distorted or unidentifiable neck anatomy

Complications

• Hemorrhage
• Injury to the posterior tracheal wall or esophagus
• Vocal cord injury
• Laceration of the thyroid gland
• Improper insertion of the cannula
• Subcutaneous or mediastinal emphysema(In case of placement of the airway cannula in the subcutaneous tissue)
• Late complications ; swallowing dysfunction, infection, voice changes, and tracheal stenosis.

Reference

Miller’s Anesthesia, 8th edition, Ch.55, P.1679

Morgan and Mikhail's Clinical Anesthesiology, 5th edition, Ch.19, P.332