Surgical Airways and Their Role in Emergency Airway Management

Cricothyrotomy, as opposed to tracheotomy, is the preferred advance airway management technique for placing an emergency surgical airway. It has been the traditional end point of the failed emergency airway in a difficult airway managment algorithm. However, the widespread acceptance of using pharmacological adjuncts to facilitate emergency intubation (i.e., rapid sequence intubation) has caused a sharp decline in its use.

The increased use of rescue ventilation devices, particularly the LMA, has dramatically impacted on the use of cricothyrotomy in the OR setting, and will likely further contribute to its declining frequency of use in the emergency setting.

The problem with surgical airways relate to its high complication rates, the difficulty of skill acquisition and maintenance, and the relatively long time to ventilation. Once the decision to do a cricothyrotomy has been made, the highest priority should be on achieving ventilation quickly to prevent hypoxic brain injury.

The traditional approach to cricothyroidotomy is to start with a vertical incision, identify the cricothyroid membrane, and then incise the membrane with a horizontal incision.  The “Rapid Four-Step” (not shown) method uses a larger scalpel (#20), a single horizontal incision through skin and membrane, and traction on the cricoid ring inferiorly, instead of cranial traction on the bottom of the thyroid cartilage.  Using a rapid approach (single incision) is faster when landmarks are easily identified.

Cricothyroidotomy (Traditional open technique) Photographs obtained with the help of William J. Levin, M.D. Landmarks identified, incision marked and performed. Operator on patient’s right side. After incision, the cricothyroid membrane is palpated. If landmarks are easily identified, a horizontal skin incision may be used, but there is an increased risk of bleeding. Membrane identified by feel; blood will obscure view.     Tracheal hook, horizontal incision, and Shiley insertion. The tracheal hook gently lifts upward. An alternative technique uses caudal retraction on cricoid ring. Forceful lifting can fracture cartilage. Hole can be widened by Trousseau dilator or blade handle. Shiley inserted with introducer at 90º to axis of trachea, until tip is within trachea, then rotated parallel to trachea for full insertion. Rigidity of Shiley prevents direct insertion.     Introducer has already been removed and inner cannula is now inserted. Disposable inner cannula needed to connect to bag or circuit. Obtain STAT chest film: pneumothorax risk!     Many practitioners use a small tracheal tube, instead of a Shiley or rigid tracheotomy tube when performing an emergency surgical airway. Tracheal tubes have a smaller outer diameter and easier insertion. Note that the OD of a Shiley 6-0 catheter is 10.8 mm vs. an 8.2 mm OD of a 6.0 tracheal tube. The average cricothyroid membrane height is between 8 and 11 mm in adults.

Melker Percutaneous Cricothyrotomy Kit
1) Insertion tips: make incision on wire large enough for dilator to enter, and grip and advance airway catheter and dilator together (image at right). 2) Available in cuffed and uncuffed versions. Inner diameter of airway catheter is 5 mm.

Seldinger (wire-guided) Cricothyrotomy Technique Photographs obtained with the help of William J. Levin, M.D. (1) After identifying cricothyroid membrane, direct needle caudally. Water in syringe reveals air on aspiration (i.e., you’re in the trachea). (2) Wire has been inserted through needle into trachea. Scalpel is used to create a small incision that will allow dilator insertion. (3) Dilator and airway catheter are advanced over wire. Grip items together or catheter will not pass. A firm, twisting motion is required.     (4) Remove wire and dilator.   5) Secure and connect to ventilation circuit.