Emergency cricothyrotomy

Military Medicine, Jul 2003 by DiGiacomo, J Christopher, Neshat, Kevin K, Angus, L D George, Penna, Kevin, Et al

Emergency cricothyrotomy is a potentially lifesaving surgical procedure used to gain prompt access to an otherwise compromised and inaccessible airway. The purpose of this photoessay is to demonstrate the technique of the procedure in a step-by-step manner so that the physician can perform this intervention with ease and facility in the most stressful of circumstances.

Introduction

Emergency cricothyrotomy is a surgical procedure used to gain prompt access to an otherwise compromised and inaccessible airway. In contradistinction to elective cricothyrotomy, a procedure that has been mostly abandoned because of concerns for long-term complications, the emergency cricothyrotomy consists of three basic steps and requires little more than a hand, a scalpel, and an endotracheal tube.

Procedure

It has been our practice to have a physician adept at emergency cricothyrotomy, often the trauma team leader, apply cricoid pressure with his gloved left hand from the right side of the table when orotracheal intubation is performed by another member of the team. (Fig. 1) This position at the patient's right side is ideal to observe the orotracheal intubation and the pulse oximeter and to provide leadership and control of the trauma resuscitation area while the personnel at the head of the bed are fully focused on intubation. Difficulties in placing the orotracheal tube can be identified early, and the physical landmarks of the cricoid and thyroid cartilages can be identified from this position (Fig. 2) should emergency cricothyrotomy become necessary.

When the decision to perform cricothyrotomy is made, the left hand becomes "fixed" and will not move until the procedure is completed and the airway controlled. After a quick application of topical antiseptic, a No. 15 scalpel is used to make a longitudinal midline incision approximately 1- to 1.5-cm long directly over the cricoid and thyroid cartilages. (Fig. 3) The incision is meant to be full thickness, which is cutting through the skin and subcutaneous tissues down to the cartilages. This is ideally accomplished in a single swipe. The slight notching, which may occur from the scalpel on the cartilages, is entirely acceptable. The fingers of the stabilizing left hand can now apply a slight increase in downward pressure, which will help draw the skin edges apart (Fig. 4) and allow visualization of the cricothyroid membrane (Fig. 5).

The scalpel is then used to make a transverse stab incision through the membrane into the airway. The handle of the scalpel is next introduced into this membrane opening and rotated 90[degrees] or the scalpel can be used to incise the membranes in the sagittal plane. Laying the scalpel aside, a 5.0, 5.5, or 6.0 endotracheal tube is introduced into the trachea with the bevel of the tube pointed caudally to a level of approximately 1 cm above the endotracheal balloon, which is then inflated (Fig. 6). The endotracheal tube is secured with umbilical tape around the neck (Fig. 7) and can be passed through the anterior opening of the rigid cervical collar if necessary.

Discussion

Emergency cricothyrotomy is a potentially lifesaving intervention that can be performed quite literally in less than 60 seconds. The ease of this procedure, when properly per-formed, is demonstrated by its successful use outside the hospital by prehospital personnel, nurses, and physicians.1-8

A longitudinal midline incision is preferable for two reasons. First, it gives a greater opportunity to locate the cricothyroid membrane by extension of the incision if the initial incision was not optimally placed. Second, it minimizes bleeding complications. As demonstrated by Goumas et al.,9 31% of the population have large-caliber veins within 1 cm of the midline. However, only 10% have veins greater than 2 mm in diameter that cross the midline. Clearly, a midline longitudinal incision is less likely to encounter bleeding complications as compared with a transverse incision.

Additional instruments are not routinely necessary to complete the procedure, although a Metzenbaum scissor, two hemostats, and a tracheal hook should be available on the procedure instrument tray. The Metzenbaum scissors and hemostats are occasionally used to spread the cricothyroid membrane. The tracheal hook is rarely, if ever, needed.

The choice of a 5.0, 5.5, or 6.0 endotracheal tube is based on the principle that this procedure is for emergency temporary access to the airway and will be revised to a formal tracheostomy. Tracheostomy cannulas are not often used in the trauma receiving area or emergency department and will therefore not be available immediately, requiring additional time and personnel effort to locate. If one were to use a tracheostomy cannula for the cricothyrotomy, the transverse plate that is used the secure the tracheostomy can overlie the upper trachea and interfere with subsequent tracheostomy placement. The orotracheal tube is readily available, is easily secured with umbilical tape around the neck, and does not interfere with access and exposure for the subsequent revision to tracheostomy.