Surgical Airways

Robert F. Reardon

Calvin A. Brown III

Michael A. Gibbs

INTRODUCTION

An open surgical cricothyrotomy, which is the preferred technique for an emergent front of neck airway (eFONA), is a unique procedure that is distinct from an elective tracheostomy. It is different because it must be performed rapidly with no time for clearing blood from the field and visualizing structures. While it is common practice for critical care providers to call a surgeon to provide this service, they should know that many surgeons (even some head and neck surgeons) don’t recognize this is a unique procedure or specifically practice it, so may not be able to complete it in a timely manner. Many nonsurgical providers believe that it is a complicated procedure that they could never master. It is a relatively simple procedure that is easily taught and learned but requires regular practice.

An emergency surgical airway is the final step of all modern airway algorithms, and it is imperative that all personnel who are responsible for advanced airway management be capable of performing this procedure expeditiously. For several reasons, the most challenging part of performing a surgical airway is making the decision to do it, rather than successfully completing the individual steps of the procedure. First, primary or rescue cricothyrotomies are exceedingly rare, even by the busiest clinicians. The incidence of emergency surgical airways in the ICU setting has not been well described. It is extremely rare in operating room (OR) settings, where the incidence of can’t intubate, can’t oxygenate (CICO) has been reported to be approximately 1:10,000 to 1:50,000.¹ However, the incidence of CICO in ICU and emergency department settings is thought to be at least 10 times higher, and the incidence of emergency surgical airways in ICUs is likely to be similar to the incidence in emergency departments (EDs). In a 2015 report from the NEAR III database, a surgical airway was used in 0.5% of 17,583 adult ED intubations.² It was used as the initial airway procedure in 0.2% and as a rescue technique after other intubation techniques failed in 0.3%. In a report on pediatric airway management from the same registry, not a single case of surgical airway management was recorded in more than 1,000 pediatric intubations.³

Second, by definition, patients in need of an emergency surgical airway are more likely to have precarious anatomy, precarious physiology, or both. Third, a case that ultimately necessitates a surgical airway is often viewed erroneously as a “failure.” Although employed during CICO scenarios that are often labeled as “failed” airways, cricothyrotomy should not be viewed as a failure.¹^,⁴ This is a systems problem that needs to be corrected at department, institution, and specialty training levels.³ Systems need to provide education, equipment, and a solid plan, and providers need to know that a surgical airway should instead be viewed as an essential, life-saving procedure in the right clinical setting. Use of a simple algorithmic approach to the failed airway (see Chapter 29, The failed airway) helps providers quickly recognize when the procedure is indicated and helps them to view this procedure as just another step in the algorithm rather than a failure.⁵^,⁶^,⁷^,⁸

On this last point, it is imperative for the treating clinician to know, instead, that a properly performed surgical airway could be the only intervention separating their patient from life and death. Using the difficult airway principles allows providers to quickly recognize when a surgical airway is indicated and helps them view it as a reasonable option. Using a system-wide approach with standard training and equipment as well as a standard algorithm will improve the performance of this rare and anxiety-provoking procedure.

Description and General Approach

An emergency surgical airway refers to establishing a definitive airway through the front of the neck (also referred to as “front of neck airway” or “FONA”), either through the cricothyroid membrane (CTM) (cricothyrotomy) or the trachea (tracheostomy). Given the complex dynamics described previously, it is imperative to select a technique that can be reliably completed by clinicians
with variable levels of experience using readily available equipment. An open scalpel, bougie-aided technique is recommended for emergency surgical airways. There has been a debate in the anesthesiology literature about the relative merits of needle cannula (Seldinger, i.e., needle-guide wire-cannula) techniques. However, the 4th National Audit Project (NAP4) of major airway complications in the United Kingdom evaluated 79 failed airways in the hospital setting that required a surgical airway and found only a 2% failure rate for open surgical airway techniques compared with a 65% failure rate for needle cannula techniques.¹ These findings led to the Difficult Airway Society’s strong recommendation for the use of scalpel cricothyrotomy techniques.⁷ Data from the NEAR in the United States and data from the NAP4 in the United Kingdom show that in EDs, open scalpel techniques are used exclusively.⁹^,¹⁰^,¹¹ It has been shown that open bougie-guided techniques are easy to teach and perform quickly, even by novices, with high rates of success.¹³^,¹⁴^,¹⁵^,¹⁶

Because this is a rare life-saving procedure, it is also imperative to practice the technique periodically so that it can be effectively performed in a high-pressure setting. Finally, it is critical to understand that in the emergency setting, surgical airways should be performed without attention paid to incisional bleeding until the airway is secured. Bleeding is inevitable, and visual confirmation of airway landmarks is not required because it is primarily a tactile procedure. Therefore, the operator must proceed without hesitation, knowing that the procedure will be performed blindly, relying on palpation of the relevant anatomic structures, with no expectation of visualizing these structures.

Indications and Contraindications

Large, multicenter studies of emergency airway management, such as those described by the National Emergency Airway Registry (NEAR), reveal that the most common indication for emergency surgical airways is as a rescue technique when other less invasive methods fail. This approach is particularly relevant during CICO scenarios. Less commonly, a surgical airway will be performed as the primary airway management method in patients for whom “standard” intubation is contraindicated or believed to be impossible. Thus, cricothyrotomy should be viewed as a rescue technique in most circumstances and one that will be used, rarely, as the primary method of securing the airway.

When deciding to initiate an emergency surgical airway, the following should be considered:

Will accessing the CTM be effective? In other words, will an incision at the level of the CTM and introduction of an airway provide adequate ventilation and oxygenation? In most cases, the answer to this question will be yes unless there is an obstructing lesion in the airway distal to the CTM. Performing a cricothyrotomy in this setting will not solve the problem and is a critical waste of time.

Will the patient’s anatomy or pathologic process make cricothyrotomy difficult to perform? Placement of the initial skin incision is based on identifying the pertinent anatomy. If adiposity, masses, burns, trauma, or infection are likely to make this procedure difficult, the strategy should be adjusted accordingly. A mnemonic for difficult cricothyrotomy (SMART) is shown in Table 27.1.

TABLE 27.1 SMART Mnemonic for Difficult Cricothyrotomy

Surgery

Mass

Access/Anatomy

Radiation

Trauma

From Gibbs MA, Caro DA, Reardon RF. Emergency surgical airways. In: Brown CA III. The Walls Manual of Emergency Airway Management. 6th ed. Wolters Kluwer; 2023:206-224. Box 19.1.

Which type of technique is best (i.e., open surgical or percutaneous)? We strongly advocate for the open bougie-aided technique based on currently available evidence. In adults, a percutaneous approach has largely been abandoned since it can be more easily confounded by obesity and altered anterior neck anatomy. For example, in obese patients, subcutaneous tissue will obscure landmarks and make needle localization difficult. For these patients, an open surgical cricothyrotomy is a better choice.

There are few contraindications to surgical airway management and nearly all are relative contraindications. One important consideration is that a cricothyrotomy is only recommended in adults and older children. Children have a small, pliable, mobile larynx and cricoid cartilage, making cricothyrotomy difficult and complication prone. For children 10 years of age or younger, unless they are unusually large for their age, avoid a standard open cricothyrotomy and instead perform a surgical tracheostomy or percutaneous procedure. Other relative contraindications to cricothyrotomy include preexisting or acute laryngeal or tracheal pathology such as tumor, infections, abscess, hematoma, or upper airway trauma that would render the procedure difficult or impossible. Although the presence of these anatomic barriers should prompt consideration of alternative techniques that might also result in a successful airway, in cases for which no alternative method is likely to be successful, cricothyrotomy should be performed.

TECHNIQUE

Anatomy and Landmarks

The CTM is the most common anatomic site of access in the emergent surgical airway, regardless of the technique used. This approach has several advantages over the trachea in the emergent setting. The CTM is more superficial than the trachea and with less soft tissue between the membrane and the skin, and it is therefore easier to rapidly identify by palpation. There is also less surrounding tissue vascularity at this level compared with the trachea and therefore a lower risk of significant arterial bleeding.

The CTM is identified by first locating the laryngeal prominence (notch) of the thyroid cartilage. Approximately one fingerbreadth below the laryngeal prominence, the membrane may be palpated in the midline of the anterior neck, as a soft depression between the inferior aspect of the thyroid cartilage above and the cricoid ring below. The relevant anatomy may be easier to appreciate in males because of the more prominent thyroid notch. We should emphasize that recent literature suggests that identification of the CTM by landmarks or palpation may be more difficult than previously assumed, especially in female and obese patients. In these patients, ultrasound is very accurate (and easy to learn) for identifying the CTM (see Chapter 10, Applied airway ultrasound). Although this may be impractical in the emergency setting, several meta-analyses show that ultrasound is the best way to identify the CTM, and this is especially important in females and obese patients.¹⁵^,¹⁶^,¹⁷ Landmark and palpation techniques are less reliable for identification of the CTM, especially in females and obese patients, with success rates ranging from 24% to 72%.¹⁸^,¹⁹^,²⁰ This is not just a theoretic problem; in the first reported case series of emergency department cricothyrotomies 10% were misplaced above the thyroid cartilage.²¹ In one randomized trial comparing ultrasound to palpation in patients with poorly defined neck landmarks, the sagittal midline (at the level of the cricoid membrane) was misidentified by 1.5 to 2.3 cm laterally with palpation alone.²² In addition, a study of 500 patients undergoing CT scans, no patient had a major vessel overlying the CTM, but 9% had a major vessel (most commonly the brachiocephalic artery) in the midline 20 mm above the sternal notch.²³ Ultrasound has been shown to be easy and accurate in locating and identifying the CTM, and many experts believe that it is the standard of care in patients with potentially difficult airways and poor external landmarks.²⁴^,²⁵ The best way to utilize ultrasound is to mark the skin overlying the CTM prior to commencing airway management. If a surgical airway is later needed, the marking remains accurate if the neck is returned to the same position, it was in (usually extended) for the ultrasound exam.²⁴^,²⁶^,²⁷^,²⁸^,²⁹

CTM localization in children is more challenging. It is disproportionately smaller in children because of a greater overlap of the thyroid cartilage over the cricoid cartilage, which is one reason cricothyrotomy is not recommended in children aged 10 years or younger.

Only gold members can continue reading. Log In or Register to continue