Cricothyroidotomy (Cricothyrotomy)

A 2002 study of the National Emergency Airway Registry database found that only 0.56% (43 of 7712) of intubations required cricothyroidotomy (cricothyrotomy).[1, 2, 3]  This percentage may be driven even lower by increasing adoption of rapid sequence intubation techniques, increased use of video-assisted intubation and other "difficult airway" devices, and increased prevalence of residency-trained emergency practitioners.[4]  However, some patients still require a surgical airway.[5, 6, 7, 8]

An emergency surgical airway can be accomplished by using one of several different methods, including the following:

• Open cricothyroidotomy ^[9]
• Needle cricothyroidotomy with jet oxygenation
• Percutaneous cricothyroidotomy using the Seldinger technique

Some evidence has supported a trend toward open cricothyroidotomy and away from needle-based approaches, at least in settings where cricothyroidotomy is not frequently performed.[10, 11]

Adults

A cricothyroidotomy is indicated when a patient’s airway cannot be secured by using nonsurgical methods or when other devices or rescue techniques (ie, intubating laryngeal mask airway, fiberoptic scope, or lighted stylet) have failed or are unavailable.[5] It is also indicated when an airway is required immediately in a patient who is not a candidate for orotracheal or nasotracheal intubation (see the video below)—for instance, in the case of severe facial trauma.[12]

In emergency settings, cricothyroidomy appears to give rise to fewer late complications than tracheostomy; however, current evidence is insufficient to support the use of emergency cricothyroidotomies as long-term airways, and thus, it is advisable to convert these cricothyroidotomies to tracheostomies in a timely manner.[13]

Children

For children younger than 12 years, needle cricothyroidotomy with percutaneous transtracheal (jet) ventilation is the surgical airway of choice. Because a child’s larynx and cricoid cartilage are very soft, mobile, and pliable, a surgical cricothyroidotomy is difficult in this setting.

An absolute contraindication for the creation of an emergency surgical airway is as follows:

• Patient younger than 12 years, unless the child is of teenage or adult size

Relative contraindications for the creation of an emergency surgical airway include the following:

• Airway obstruction distal enough to the cricoid membrane that a cricothyroidotomy would not provide a secure airway with which to ventilate the patient
• Presence of a SHORT neck (ie,  Surgery [history of prior neck surgery], Hematoma, Obesity, Radiation [evidence of radiation therapy], or Trauma/burns), making it difficult to locate the patient’s anatomic landmarks or causing an increased risk of further complications
• Tumor, infection, or abscess at the incision site
• Lack of operator expertise

Almost no literature is available comparing surgical cricothyroidotomy with needle cricothyroidotomy. Some comparisons have been made between the use of a cricothyrotome kit and the rapid four-step surgical cricothyroidotomy, but they have demonstrated no significant difference in outcomes or complications.

Kwon et al assessed the incidence and outcomes of cricothyroidotomy in a "cannot intubate, cannot oxygenate" (CICO) situation.[14] A total of 10,187 tracheal intubations were attempted, and 23 patients received cricothyroidotomy (22 in the emergency department [ED] and one in the endoscopy room). The survival rate at hospital discharge was 47.8% (11/23). Aside from cases of cardiac arrest at admission, the survival rate was 62.5% (10/16). Cricothyroidotomy was successful in 17 patients (73.9%), nine (52.9%) of whom survived; it failed in six (26.1%), two (33.3%) of whom survived. After failed cricothyroidotomy, airways were secured via tracheal intubation, nasotracheal intubation, or tracheostomy.

Equipment for open cricothyroidotomy (cricothyrotomy) includes the following:

• Cuffed, nonfenestrated tracheostomy tubes, No. 4 and No. 5 
• Scalpel, No. 11
• Trousseau dilator
• Tracheal hook
• 4 × 4 gauze/sponges
• Optional equipment - Small hemostats (2), surgical drapes, 1% lidocaine with syringe and needle

Equipment for needle cricothyroidotomy includes the following:

• Over-the-needle catheter, 12 or 14 gauge, 8.5 cm
• Over-the-needle catheter, 16 or 18 gauge, 8.5 cm (for pediatric patients)
• Syringe, 10 mL
• Scalpel, No. 11
• 4 × 4 gauze/sponges
• Nasal cannula or oxygen tubing with Y-connector
• Optional equipment - Surgical drapes, 1% lidocaine with syringe and needle

Equipment for percutaneous cricothyroidotomy using the Seldinger technique includes the following:

• Cricothyrotome kit
• Scalpel, No. 11
• 4 × 4 gauze/sponges
• Optional equipment - Surgical drapes, 1% lidocaine with syringe and needle

Anesthesia

If time permits and the patient is not unresponsive, injection of the skin and subcutaneous tissue over the cricothyroid membrane with 1% lidocaine solution provides adequate anesthesia.

Positioning

Position the patient supine, with the neck in a neutral position.

An emergency surgical airway can be created by means of several different methods, including open cricothyroidotomy (cricothyrotomy), needle cricothyroidotomy with jet oxygenation, and percutaneous cricothyroidotomy using the Seldinger technique.

Open cricothyroidotomy

Steps in the procedure are as follows:

• Assemble and prepare equipment
• Position the patient supine, with the neck in a neutral position
• Clean the patient’s neck in a sterile fashion using antiseptic swabs
• Anesthetize the area locally, if time allows
• Locate the cricothyroid membrane anteriorly between the thyroid and the cricoid cartilage
• Stabilize the trachea with the left hand until the trachea is intubated
• Make a 2- to 3-cm midline vertical incision through the skin from the caudal end of the thyroid cartilage to the cephalic end of the cricoid cartilage
• Make a 1- to 2-cm transverse incision through the cricothyroid membrane
• Insert the scalpel handle into the incision and rotate 90° (a hemostat may also be used to open the airway)
• Insert a tracheal hook into the opening, hooking the caudal end of the opening, and lift, allowing for passage of an appropriately sized cuffed endotracheal or tracheostomy tube (usually No. 5 or No. 6), directing the tube distally.
• One alternative to the preceding step is to insert the tube through the opening produced by the opened hemostat; a second alternative is to hold the handle of the scalpel straight down in the opening, slide the handle cephalically, insert the tube straight down along the handle until it hits the back of the trachea, angle the tube caudally, and advance the tube
• Inflate the cuff; observe and check for chest rise
• Secure the airway
• Take care not to cut the thyroid or the cricoid cartilage

A surgical tracheostomy is depicted in the video below.

A randomized controlled study comparing surgical cricothyroidotomy with percutaneous Seldinger-based cricothyroidotomy as performed 21 emergency physicians and nine emergency medicine trainees found that the surgical procedure could be performed more quickly and comfortably and was the preferred technique in this study group.[11]

Needle cricothyroidotomy

Steps in the procedure are as follows:

• Follow the first four steps listed above for surgical cricothyroidotomy
• Assemble a 12- or 14-gauge (16- or 18-gauge in children) 8.5-cm over-the-needle catheter to a 10-mL syringe
• Locate the cricothyroid membrane anteriorly between the thyroid and the cricoid cartilage
• Stabilize the trachea with the thumb and forefinger of one hand
• Using the other hand, puncture the skin in the midline with the needle over the cricothyroid membrane; a small incision with a No. 11 blade may be made first to facilitate passage of the needle
• Direct the needle at a 45° angle caudally while applying negative pressure to the syringe
• Maintain needle aspiration as the needle is inserted through the lower half of the cricothyroid membrane; aspiration of air signifies entry into the tracheal lumen
• Remove the syringe and needle while advancing the catheter to the hub
• Attach the oxygen catheter, and secure the airway

Percutaneous cricothyroidotomy using Seldinger technique

The cricothyrotome kit for this procedure is used in much the same way as in a needle cricothyroidotomy but relies on the Seldinger technique. These kits are available in some hospitals and should be used only in patients older than 12 years. (See the video below.)

Steps in the procedure are as follows:

• Follow the first four steps listed above for surgical cricothyroidotomy
• Locate the cricothyroid membrane anteriorly between the thyroid and the cricoid cartilage
• Stabilize the trachea with the thumb and forefinger of one hand
• Using the other hand, puncture the skin in the midline with the finder needle with attached syringe over the cricothyroid membrane; a small incision with a No. 11 blade may be made first to facilitate passage of the needle
• Direct the needle at a 45° angle caudally while applying negative pressure to the syringe
• Maintain needle aspiration as the needle is inserted through the lower half of the cricothyroid membrane; aspiration of air signifies entry into the tracheal lumen
• Remove the syringe, leaving the needle in place, and advance the guide wire through the needle
• A small incision with a No.11 blade may be needed to enlarge the hole before insertion of the dilator; it is recommended to make this incision before removing the needle so as not to cut the guide wire accidentally
• Insert the dilator–airway tube combination over the guide wire; once the airway device is in place, remove the dilator and the guide wire
• Attach the oxygen catheter, and secure the airway

Percutaneous transtracheal ventilation

Connect the cannula to oxygen at 15 L/min (40-50 psi) using a Y-connector or through a hole cut in the side of a nasal cannula. Intermittent ventilation (1 s on, 4 s off) can be achieved by placing a thumb over the open end of the Y-connector or cannula.

This method can be used for about 30-40 minutes. However, it causes an accumulation of carbon dioxide and therefore must be used sparingly in patients who have sustained head trauma.

Complications associated with open cricothyroidotomy include the following:

• Aspiration
• Creation of false passage into the tissue
• Subglottic stenosis
• Laryngeal stenosis
• Hemorrhage/hematoma
• Esophageal/tracheal laceration
• Mediastinal emphysema ^[15]
• Vocal cord injury

A systematic review by DeVore et al found that the most frequent early complication after emergency surgical cricothyroidotomy was failure to obtain an airway; the most common long-term complication was airway stenosis.[16]  A retrospective single-institution case series by Moroco et al found improper placement to be the most common complication.[17]

Complications associated with needle cricothyroidotomy include the following:

• Inadequate ventilation/hypoxia
• Aspiration (blood)
• Esophageal laceration
• Posterior tracheal wall perforation
• Subcutaneous emphysema
• Thyroid perforation
• Hypercarbia

Ultrasonographic (US) guidance may reduce the incidence of airway damage.[2]  Whether airway injury is present after the procedure may be determined by means of fiberoptic bronchoscopy, radiography, or computed tomography (CT).[18]

Complications associated with percutaneous transtracheal ventilation include the following:

• Pulmonary rupture
• Pneumothorax/ tension pneumothorax