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Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e

Chapter 30: Surgical Airways Michael D. Smith; Donald M. Yealy

INTRODUCTION

Establishing an airway by means of a surgical approach—incision or percutaneous insertion—is a challengingprocedure deployed at high-risk and high-stress moments when basic airway maneuvers have failed. The keyis preparation and practice, which means having all equipment ready and available (o�en in a common cartto ensure consistency) and prior practice in laboratory settings if not recently performed in clinical care.Knowing what options are available and then choosing one and implementing it before respiratory collapsewill improve the outcome. The success rates depend largely on the preparedness of the ED and the training

of the sta�.1,2

Surgical cricothyrotomy refers to incision of the cricothyroid membrane under direct visualization andinsertion of a tracheostomy tube either directly through the incision or by using the Seldinger technique.Needle cricothyrotomy is a dated term referring to insertion of a 12- to 16-gauge needle catheter into thetrachea and connected to either a bag-valve device or wall oxygen. We do not recommend needlecricothyrotomy. Percutaneous transtracheal jet ventilation uses a 12- to 16-gauge catheter inserted into thecricothyroid membrane and connected to a high-pressure (35 to 50 psi) oxygen source for both oxygenationand ventilation.

PATIENT SELECTION

The primary indication for surgical airway placement is a "can't intubate, can't ventilate" scenario. Mostemergency surgical airways follow a failed attempt to establish an oral endotracheal airway. Cricothyrotomyor jet ventilation can be used before laryngoscopy and direct glottic intubation if the latter is likely to failbecause of anatomic impingement or any other cause that impedes visualization, notable blood, secretions,swelling, or foreign matter. It is not necessary to try to intubate once before moving to cricothyrotomy; thiso�en simply enhances the risk of harm.

Di�iculty in establishing an airway may be due to anatomy (short, obese neck), a disease state (epiglottitis,laryngeal edema, paralyzed vocal cords, or retropharyngeal abscess), trauma from distortion of the neck byhematoma (cervical fracture or major vessel injury), aspiration of blood (facial trauma), or loss of supportingstructures (mandibular fractures). Assess for these factors before any laryngoscopic attempts, have a surgical

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airway plan in mind, and have equipment ready at the bedside to manage impending or actual respiratoryfailure.

In a patient with a failed intubation attempt, the best course of action is to use bag-valve mask ventilation torestore or maintain gas exchange while regrouping. If bag mask ventilation is successful, try another attemptat laryngoscopy with a di�erent operator and approach, rather than performing immediate cricothyrotomy.Clinical signs and symptoms of airway obstruction—one common reason to choose a surgical airway—arelisted in Table 30-1.

TABLE 30-1

Clinical Manifestations Associated with Acute Airway Obstruction

Etiology Manifestation

Vascular Hematoma

External hemorrhage

Hypotension

Hemoptysis

Laryngotracheal Stridor

Subcutaneous air (massive)

Hoarseness

Dysphonia

Hemoptysis

Pharyngeal and/or hypopharyngeal Subcutaneous air

Hematemesis

Dysphagia

Sucking wound

PATIENT AGE

Most children do not require advanced airway management, especially a surgical airway. In children under12 years, the larynx is more easily damaged by cricothyrotomy, and placement is challenged by compressiblestructures and less distinction between cartilages. Late airway complications, especially stenosis, occur more

o�en in children.3 For children under 12 years old, especially those under 8 years, tracheotomy is preferred;the di�iculty is that few emergency physicians have experience performing this successfully, making it anunavailable practical option. Alternatively, a 14- to 16-gauge catheter inserted percutaneously through thecricothyroid membrane to either oxygenate (temporizing for minutes, done by connecting the catheter to

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high-flow wall oxygen) or jet ventilate (connecting to 0.5 psi/kg compressed gas source, using a 1:3 secondinsu�lation/expiration ratio) is an option while awaiting tracheotomy. Neither technique is well studied,although jet ventilation o�ers wider capabilities but requires specific equipment ready in advance. Again, thekey to success is advance thought, planning, and equipment preparation coupled with training for thisspecific event. Needle/jet approaches are discussed in more detail later.

INJURIES REQUIRING OPEN OR PERCUTANEOUS CRICOTHYROTOMY

Penetrating trauma to the neck a�ecting a major artery (carotid, vertebral, or thyroid) may create anexpanding hematoma and obstruct the airway. If free blood spills into the oro- or hypopharynx, directvisualization for intubation is o�en not possible. Placing a cu�ed tracheostomy tube a�er cricothyrotomy isthe best option to restore gas exchange and limit aspiration. Di�iculty in establishing an airway occurs in

approximately 10% of patients with penetrating cervical trauma.4

Blunt trauma to the neck or face may cause hemorrhage of the so� tissues or injury to the trachea/larynx,including rupture. If the trachea or larynx is disrupted, do not attempt cricothyrotomy; in this rare setting, anemergency tracheostomy is needed. In blunt facial trauma, the principal cause of death is airway obstructionfrom bleeding (o�en from fractures) or so� tissue swelling; a surgical airway can prevent death and harm ifdeployed quickly and with skill.

TYPE OF EMERGENCY AIRWAY AND TUBE SELECTION

Cricothyrotomy is preferred over percutaneous approaches (except for children <12 years old). The mostskilled provider should perform this procedure to optimize success and limit harm.

Although any large-bore tube is adequate, we suggest using a tracheostomy tube because it has an obturatorto ease insertion, is shorter and easier to suction, and secures well by using the flanges on each side and acloth ribbon around the neck or suturing to nearby skin (Figure 30-1). When an endotracheal tube is placedduring cricothyrotomy, the tube is di�icult to secure and may be advanced too deeply; it also may beinadvertently directed cephalad (the wrong way) when placed through the cricothyrotomy incision. To avoid

this, many use a gum elastic bougie to ensure tracheal placement and the correct tube direction.5 If astandard endotracheal tube is used and then designated for change to a tracheostomy tube, use theSeldinger (change over a guide device) technique. Use a suction catheter with the suction vent cut o� at oneend as an obturator for endotracheal tube removal and tracheostomy tube insertion.

FIGURE 30-1.

Tracheostomy tube with obturator. [Photo used with permission of David E�ron, MD.]

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The diameter of the tube inserted is crucial. A common choice for an adult is a 6-mm tracheostomy or 6- to 7-mm endotracheal tube. Do not choose a larger (≥7 mm) tube or one smaller than 4 mm. Larger tubes aredi�icult to insert in the narrow space between the cricoid and thyroid cartilages. If airway pressures are highwith the small-diameter tube or ventilation is inadequate, consider changing to a larger diameter tube.Ventilation problems may occur when a smaller tube is used (3-mm internal diameter or less.) Any tube witha 4- or 5-mm internal diameter will allow adequate volume ventilation in most patients, although at 4 mmthere is limited area for suctioning and aggressive minute ventilation; for that reason, select a 4- to 5-mm sizeonly if a 6-mm tube is unavailable or cannot be placed.

SURGICAL CRICOTHYROTOMY

ANATOMY

The cricothyroid membrane is located between the thyroid and cricoid cartilages (Figure 30-2A). Bothstructures are easily palpated but are not directly seen because they are covered with the pretracheal fascia.In men, the thyroid cartilage is prominent and creates the "Adam's apple"; in women and children, thethyroid and cricoid cartilages can be hard to distinguish from each other.

FIGURE 30-2.

A. Neck anatomy. B. Location of the cricothyroid membrane.

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FIGURE 30-3.

Locate the cricothyroid membrane. [Photo used with permission of Jennifer McBride, PhD, and Michael D.Smith, MD.]

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FIGURE 30-4.

Make a midline vertical incision. The pretracheal fascia is seen through the incision. Bleeding is less likelywith a vertical incision. [Photo used with permission of Jennifer McBride, PhD, and Michael Phelan, MD.]

FIGURE 30-5.

Perforate the cricoid membrane with a horizontal incision. [Photo used with permission of Jennifer McBride,PhD, and Michael Phelan, MD.]

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FIGURE 30-6.

Widen the opening. [Photo used with permission of Jennifer McBride, PhD, and Michael Phelan, MD.]

FIGURE 30-7.

Insert a tracheostomy tube with obturator. [Photo used with permission of Jennifer McBride, PhD, andMichael Phelan, MD.]

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The cricothyroid membrane is found approximately one-third the distance from the manubrium to the chinin the midline in patients with normal habitus (Figure 30-2B). In a patient with a short, obese neck, themembrane may be hidden at the level of the manubrium. In a patient with a thin, long neck, it may bemidway between the chin and the manubrium. The thyroid gland overlies the trachea; both structures aredi�icult to palpate. One easy way to find the cricoid membrane is to slowly palpate the trachea as you moveup toward the head from the sternal notch; when your fingers "fall o�" a�er a firm structure, you havepalpated the thyroid cartilage. Next, slowly palpate downward toward the feet, and the first "so� spot" a�erthat thyroid cartilage is the cricoid membrane.

The vascular structure potentially injured during the course of a properly performed cricothyrotomy is athyroid artery, a branch of the aorta running up to the thyroid gland in the midline. This vessel infrequentlyreaches the level of the cricothyroid membrane. A carotid injury is potential when landmarks are not seen ornot adhered to or when technique is poor; this can be catastrophic and requires immediate direct pressure toavoid harm.

EQUIPMENT

The equipment needed to perform a surgical cricothyrotomy is listed in Table 30-2.

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TABLE 30-2

Equipment Needed to Perform a Surgical Cricothyrotomy

Personal protective equipment

Scalpel with a #10 (preferable because of its greater width) or #11 blade

A 6-mm endotracheal tube or tracheostomy tube (latter preferred), plus a smaller one available

Tape to secure the tube in place

Cloth ribbon and sutures to secure tracheostomy tube in place

Bag-valve mask device and oxygen source

Gum elastic bougie for guiding tube

Suction devices

PATIENT PREPARATION AND POSITIONING

Place the patient supine, with the neck slightly hyperextended if no cervical trauma is present (neutral ifthere is suspected trauma) so neck structures can be palpated and identified. If time permits, applyantiseptic solution to the skin. Ventilate with a bag-valve mask connected to 100% oxygen while preparing.

PROCEDURE

The procedure for performing a surgical cricothyrotomy is summarized in Table 30-3.

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TABLE 30-3

Performing a Surgical Cricothyrotomy

Step Comment

1. Stand to one side of the

patient at the level of the

neck.

Right-handed practitioner—stand on the patient's right side.

Le�-handed practitioner—stand on the patient's le� side.

2. Locate the cricothyroid

membrane.

Locate the cricoid ring.

Place the index finger at the sternal notch and palpate cephalad until the

first rigid structure is felt (cricoid ring), or use "fall o� and return" approach

noted earlier.

Roll the index finger one finger breadth above to locate the membrane

between the cricoid and thyroid cartilages (Figure 30-3).

3. Using the thumb and

middle finger of the

nondominant hand, stabilize

the two cartilages.

—

4. Use the scalpel to make a

vertical incision in the

midline between the two

cartilages, extending if

needed.

Incise through the skin and subcutaneous tissues.

The structures are superficial, so do not incise deep to avoid damage to the

cricoid or thyroid cartilage or vascular structures (Figure 30-4). The

membrane is felt, not directly seen, a�er incision.

5. With the scalpel blade

positioned horizontally,

perforate the cricothyroid

membrane so that the blade

goes in approximately half its

length.

The horizontal orientation is in anatomic alignment with the membranes to

avoid vascular injury (Figure 30-5). Once the membrane is perforated, do not

leave it empty; slide forceps or dilator around the blade or place a bougie

before removing the scalpel.

6. Widen the incision

opening.

A dilator or mosquito or Kelly clamp may be used (Figure 30-6).

7. Place the tube in the

opening.

Although instinct may guide you to direct the tracheostomy tube posterior,

remember that the trachea is superficial and the tube should follow the

tracheal axis (Figure 30-7).

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Step Comment

8. Connect to a bag-valve

mask device for ventilation.

Check for breath sounds with

ventilation.

If no ventilation is heard bilaterally, pull the tube out and reinsert it.

Recheck for breath sounds to ensure that the endotracheal tube is correctly

positioned a�er any manipulation.

When inserting a standard endotracheal tube, listen for asymmetry of

breath sounds. If breath sounds are absent on the le� side, then the tube

has been inserted down the right mainstem bronchus and needs to be

pulled back a few centimeters. If using an endotracheal tube, insert no more

than 2–3 cm to avoid mainstem bronchus placement.

9. Secure the tube carefully

with a ribbon and/or

adhesive tape.

More challenging with a standard endotracheal tube.

10. Apply dressing and

further secure the tube.

If a tracheostomy tube has been used, fashion a simple dressing by cutting a

slit halfway down the middle of a 4×4 gauze dressing and placing it under

the tracheostomy tube.

Secure the tube with a ribbon placed through the flanges of the

tracheostomy tube.

For added security, use 2-0 nylon sutures to fix the tube to the skin.

Consider changing endotracheal tubes to tracheostomy tubes whenever

possible.

SURGICAL CRICOTHYROTOMY USING SELDINGER TECHNIQUE

This method uses the Seldinger technique (Figure 30-8). Make a small vertical incision through the skin at thecricothyroid membrane. Insert the needle and aspirate air to make sure the needle is in the trachea. Next,pass the guide wire through the needle, directing the guide wire caudally. Place a tracheostomy tube overthe dilator, and make a "nick" in the skin to ease penetration. Then pass the dilator, with the tracheostomytube, over the guide wire into the trachea. Once the dilator is in the trachea, remove the guide wire, direct thetracheostomy tube into the trachea, and verify correct placement. Indications and complications are similarto the open method, and direct comparisons in real use do not exist. Multiple commercial kits exist, butproper use requires deliberate, repetitive training.

FIGURE 30-8.

Placement of a percutaneous cricothyrotomy with a commercial kit and the Seldinger technique. [Photoused with permission of David E�ron, MD.]

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FIGURE 30-9.

Introduce the catheter into the larynx. A. Introduce the catheter into the larynx skin at a 90-degree angle tothe skin. B. When air returns, change the angle to 45 degrees. [Photo used with permission of JenniferMcBride, PhD, and Michael D. Smith, MD.]

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FIGURE 30-10.

Attach the high-flow regulator via connective tubing to the catheter and start ventilation with high-pressure100% oxygen source. Note: Stabilize catheter at the base to avoid dislodgement (not done in figure fordisplay purposes). [Photo used with permission of David E�ron, MD.]

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COMPLICATIONS

Acute complications a�er emergency cricothyrotomy occur in up to 15% of cases.6 Venous bleeding usuallyoccurs from small veins and stops spontaneously. Using a vertical neck incision that is not too long decreasesthe chance of ongoing bleeding. Arterial bleeding can be from the thyroid artery or from a small artery at thebase of the cricothyroid membrane. The first step in controlling ongoing bleeding is to apply gentle pressure.If bleeding persists, topical hemostatic agents or ligation may be necessary. A small amount of bleedingusually creates no hemodynamic concerns, but it can make the procedure more challenging.

In an obese patient, it is possible to place the tube anterior to the larynx and trachea into the mediastinum,making ventilation impossible. Signs of an incorrectly positioned tube are high airway pressures, absentbreath sounds, and massive subcutaneous emphysema. If this complication is suspected, remove the tubeand make a second attempt at insertion. Endotracheal tubes passed through the cricoid membrane may curltoward the mouth, making ventilation impossible. A gum elastic bougie can help direct the endotracheal

tube.5

Laceration of the trachea, esophagus, or recurrent laryngeal nerves is rare and is more likely to occur if one isunfamiliar with the neck anatomy. Pneumothorax is usually secondary to barotrauma caused by ventilationinitiated immediately a�er tube placement.

A tube le� in the narrow space between the cricoid and thyroid cartilages can erode both cartilages, andbacterial chondritis may occur. The cartilages will be destroyed and eventually scar, leading to stenosis and

loss of the function of the larynx. Because cricothyrotomy has a high incidence of airway stenosis,6 a changeto tracheostomy is common a�er 2 to 3 days.

PERCUTANEOUS CRICOTHYROTOMY AND TRANSTRACHEAL JETINSUFFLATION

We do not recommend "needle cricothyrotomy"—defined as a 12- to 16-gauge needle catheter inserted intothe trachea and connected to either a bag-valve device or wall oxygen—as a rescue technique. Althoughmany texts and general guidelines discuss this approach, it will not reverse ventilation gaps and will only

modestly aid oxygen delivery.7,8 In addition, the use of needle cricothyrotomy requires rapid reestablishmentof a proper airway.

The only small catheter option is correctly performed jet ventilation. The proper equipment must beprocured and maintained and the procedure must be practiced, because many physicians lack the proper

equipment and knowledge of the procedure.9 Do not perform jet ventilation without the correct high-pressure equipment ready in advance and without antecedent practice; one cannot simply "put thistogether" at the time of critical need.

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Jet ventilation uses a small catheter but also a pressured oxygen source—35 to 50 psi (much high than exitingstandard bag-valve devices and oxygen wall outlets) to deliver 500 to 12,000 cc of gas. In jet ventilation, thecatheter and high-pressure gas provide volume inhalation, and the native airway is the passive exhalation

route. With proper jet ventilation, adequate oxygenation and ventilation occur.10 Duration is limited only byairway desiccation from nonhumidified gas, an e�ect that takes hours to a day to occur. Properly performedjet ventilation does not create hypercarbia or the need for rapid reestablishment of another airway; onlypoorly performed or "needle cricothyrotomy" low-pressure techniques create that situation.

Jet ventilation does not harm the lower airways because the high pressure dissipates rapidly; it also allowssome aspiration control as the expelled gas clears the upper airway. The only absolute contraindication iscomplete, including expiratory, airway obstruction; this is exceptionally rare because most upper airwayobstruction is inspiratory, including obstruction from masses. Relative contraindications are unfamiliarity,not having the equipment ready, and local infection at puncture site.

ANATOMY, INDICATIONS, AND CONTRAINDICATIONS

The anatomy and general indications are listed in earlier in "Surgical Cricothyrotomy."

EQUIPMENT NEEDED

Equipment needed for transtracheal jet ventilation is listed in Table 30-4. The key is having this prepared inadvance; trying to use standard oxygen tubing, three-way stopcocks, or bag-valve devices or attaching towall outlets turned to highest liter flow will not allow for proper jet ventilation.

TABLE 30-4

Equipment Needed to Perform Jet Ventilation

Personal protective equipment

A 16 gauge or larger sheathed needle catheter or a commercial jet catheter

A 3-mL syringe

Connective tubing and connectors designed for high pressure (not standard oxygen tubing/securing

attachments; these will not allow jet ventilation)

High-flow regulator with insu�lation control

A high-pressure oxygen source; your respiratory technician can have the jet insu�lator attached to an E

cylinder or wall unit before downregulation to ensure high-pressure (35–50 psi) gas

PROCEDURE

The steps of performing jet ventilation are summarized in Table 30-5. Optimize preprocedural oxygenationand ventilation if possible (although o�en failure is the reason for the procedure).

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TABLE 30-5

Performing Jet Ventilation

Step Comment

1. Stand to one side of the patient at the

level of the neck.

Right-handed practitioner—stand on the patient's right side.

Le�-handed practitioner—stand on the patient's le� side.

2. Locate the cricothyroid membrane. Locate the cricoid ring.

Place the index finger at the sternal notch and palpate cephalad

until the first rigid structure is felt (cricoid ring).

Roll the index finger one finger breadth above to locate the

"hollow" between the cricoid and thyroid cartilages, locating

the cricothyroid membrane (Figure 30-3).

3. Attach a 3-mL syringe to the catheter. Smaller catheters tend to kink easily, as noted in photos, and

limit gas flow. Use of a 16-gauge or larger, commercial catheter

is preferred (13 gauge).

4. Introduce the catheter into the

subcutaneous tissue at a 45-degree angle

to the skin, aiming toward the patient's

feet.

Figure 30-9.

5. Aspirate gently while advancing the

catheter over the needle.

 

6. When air suddenly returns (indicating

entry into the airway), advance the

catheter over the needle into the larynx.

Free air aspiration = intratracheal placement; any resistance

means not clearly in trachea.

7. Once fully inserted, remove the needle

and reaspirate to ensure ongoing free air

aspiration.

If resistance to air aspiration occurs a�er advancement, remove

catheter and retry. Once the catheter is fully inserted, a

stabilizing hand must always be present; do not ever let the

proximal end be unsecured.

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Step Comment

8. Attach the high-flow regulator via

connective tubing to the catheter and

start ventilation with a 100% oxygen

source. If a child, use 0.5 psi/kg to start

and a 16-gauge catheter (Figure 30-10).

Connect to a high-pressure source (35–50 psi); bag-valve devices

and standard wall oxygen valves opened to 15 L/min do not

deliver 35–50 psi. The jet device is attached directly to wall unit

before standard regulators or directly to E cylinder (latter will

allow >30 min of ventilation if full).

Insu�late by holding valve down (open) for maximum of 1 s, and

then release the occlusion for 4 s. Listen for symmetric breath

sounds, watch the chest rise and fall, and measure exhaled CO2

if desired.

9. Hold the catheter securely to avoid

dislodgement. The catheter tends to kink

easily, so maintain care with positioning.

The inspiration:expiration of 1:4 allows passive exhalation and

avoids over ventilation. Monitor like any volume ventilation

technique.

10. Stabilization is similar to

cricothyrotomy, and plan for next airway;

gas exchange will be adequate for a

prolonged interval, allowing a careful and

controlled approach.

Dressings are not necessary, and commercial kits have straps

like tracheostomy tubes.

The exhaled gas o�ers some aspiration protection.

COMPLICATIONS

Complications from the jet ventilation procedure are infrequent. Failure to properly secure the catheter canlead to displacement. Bleeding at the puncture site and infection may occur. Inadvertent perforation of theesophagus or back wall of the trachea or larynx is rare. Massive subcutaneous emphysema can developduring ventilation. The catheter also may be misplaced in the so� tissues of the neck. Even if the cricoidmembrane is not used (from misidentification), jet punctures rarely cause long-term airway complications,an advantage over cricothyrotomy.

DEVICE REMOVAL

Jet ventilation allows a more controlled approach to airway management; plan the next step(s) carefully andwithout fear of ventilation failure if done properly, avoiding any rush to another procedure. O�en, a betterlaryngoscopic attempt or a formal tracheostomy can occur once time pressures are abated with jetventilation.

REFERENCES

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1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

Davies  P: A stab in the dark! Are you ready to perform needle cricothyroidotomy? Injury 30: 659, 1999. [PubMed: 10707239]  

Eisenburger  P, Laczika  K, List  M  et al.: Comparison of conventional surgical versus Seldinger techniqueemergency cricothyrotomy performed by inexperienced clinicians. Anesthesiology 92: 687, 2000. [PubMed: 10719947]  

Cote  CJ, Hartnick  CJ: Pediatric transtracheal and cricothyrotomy airway devices for emergency use: whichare appropriate for infants and children? Paediatr Anaesth 19: 66, 2009. [PubMed: 19572846]  

Grewal  H, Rao  PM, Mukerji  S, Ivantury  RR: Management of laryngotracheal injuries. Head Neck 17: 494,206.  [PubMed: 8847208]

Smith  MD, Katrinchak  J: Use of a gum elastic bougie during surgical cricothyrotomy. Am J Emerg Med 26:e738, 2007. [PubMed: 18606350]

Sakles  JC, Deacon  JM, Bair  AE  et al.: Delayed complications of emergency airway management: a studyof 533 emergency department intubations. West J Emerg Med 9: 190, 2008. [PubMed: 19561743]  

Yealy  DM, Plewa  MC, Stewart  RD: An evaluation of cannulae and oxygen sources for pediatric jetventilation. Am J Emerg Med 9: 20, 1991. [PubMed: 1985643]  

Yealy  DM, Stewart  RD, Kaplan  R: Myths and pitfalls in emergency translaryngeal ventilation: correctmisimpressions. Ann Emerg Med 17: 690, 1988. [PubMed: 2968062]  

Green  L. Can't intubate, can't ventilate! A survey of knowledge and skills in a large teaching hospital. Eur JAnaesthesiol 26: 480, 2009. [PubMed: 19445058]  

Ward  KR, Menegazzi  JJ, Yealy  DM, Klain  M, Molner  R, Goode  J: Translaryngeal jet ventilation and end-tidal PCO2 monitoring during varying degrees of upper airway obstruction. Ann Emerg Med 20: 1193, 1991. [PubMed: 1952304]  

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