Needle cricothyroidotomy with percutaneous transtracheal ventilation

INTRODUCTION — Needle cricothyroidotomy and percutaneous transtracheal ventilation will be discussed here. Surgical cricothyroidotomy and cricothyroidotomy using the Seldinger technique are discussed separately. (See "Emergency cricothyrotomy (cricothyroidotomy) in adults".)

DEFINITIONS — It is important to distinguish between the different methods of emergency airway access and specialized ventilation. For the purposes of this review, definitions are as follows:

Needle cricothyroidotomy — Needle cricothyroidotomy involves passing an over-the-needle catheter through the cricothyroid membrane (figure 1). This procedure provides a temporary secure airway to oxygenate and ventilate a patient in severe respiratory distress in whom less invasive techniques (eg, bag-valve-mask ventilation, laryngeal mask ventilation, endotracheal intubation) have failed or are not likely to be successful (ie, "can't intubate, can't ventilate") [1-5].

Needle cricothyroidotomy may be performed on patients of any age but is considered to be preferable to surgical cricothyroidotomy in infants and children up to 10 to 12 years of age because it is anatomically easier to perform with less potential damage to the larynx and surrounding structures [6-9].

Surgical cricothyroidotomy — Surgical cricothyroidotomy is an emergent airway approach in which the clinician makes an incision in the cricothyroid membrane and passes a tracheostomy or endotracheal tube into the trachea. The standard, four step, and Seldinger techniques are common methods of surgical cricothyroidotomy. (See "Emergency cricothyrotomy (cricothyroidotomy) in adults".)

Surgical cricothyroidotomy provides more effective ventilation than needle cricothyroidotomy because of the larger diameter tube used and is typically chosen instead of needle cricothyroidotomy in adults and children over 10 to 12 years of age.

Percutaneous transtracheal ventilation — Percutaneous transtracheal ventilation (PTV) involves oxygenation and ventilation via a needle or surgical cricothyroidotomy using an improvised ventilation device. PTV is considered a form of conventional ventilation. However, it is sometimes referred to as "jet ventilation" when a high pressure source is used to deliver oxygen [10-12]. For this topic, PTV refers to use of a bag-valve mask or wall oxygen as the delivery source. (See 'Bag-valve-mask connector options' below and 'Oxygen tubing connector options' below.)

Transtracheal jet ventilation — Transtracheal jet ventilation refers to high frequency, low tidal volume ventilation provided via a laryngeal catheter by specialized ventilators that are usually only available in the operating room or intensive care unit [10,11]. Thus, transtracheal jet ventilation is not considered a type of conventional ventilation. This procedure is occasionally employed in the operating room when a difficult airway is anticipated (eg, Treacher Collins syndrome, Robin sequence, head and neck surgery with supraglottic or glottic obstruction) [13-16].

ANATOMY — The cricothyroid membrane, as the name implies, is bound by the cricoid cartilage inferiorly and the thyroid cartilage superiorly (figure 1). The key anatomic landmarks are (from cephalad to caudad): hyoid cartilage, thyroid cartilage, cricothyroid membrane, cricoid cartilage, and the tracheal rings.

The cricothyroid arteries and veins usually overlie the apical portion of the membrane and come from the sides, anastomosing in the midline [17]. Thus, needle cricothyroidotomy should be attempted in the central, lower portion of the membrane (figure 1).

In fresh adult cadavers, the size of the cricothyroid membrane was found to vary from 8 to 19 mm (mean 13.7 mm) in the vertical dimension, and from 9 to 19 mm (mean 12.4 mm) in the transverse dimension [18]. A more recent study in the United Kingdom trauma population, using electronic calipers on 482 reformatted computed tomography scans, found the mean height to be much smaller at 8 mm in males and 6 mm in females [19]. These data suggest that catheters up to 13-gauge can be safely used in a patient with a fully developed airway. The cricothyroid membrane has a mean height of 2.6 mm (SD: 0.7) and width of 3 mm (SD: 0.6) in neonatal cadavers (mean height of 44.9 cm and a mean weight of 2 kg) [20]. The clinician should place the largest catheter possible using this limited information and palpation of the cricothyroid membrane as a guide. The mean depth of tissue overlying cricothyroid membrane in adults is about 2.3 mm [21].

PHYSIOLOGY — Needle cricothyroidotomy was originally used for passive transtracheal oxygenation in the 1950s [22]. Eventually, needle cricothyroidotomy with percutaneous transtracheal ventilation (PTV) emerged as the invasive rescue method of choice because it provided oxygenation as well as clearance of carbon dioxide. This approach could sustain life for a longer period of time than passive transtracheal oxygenation alone [1,13,23-25]. Successful use of needle cricothyroidotomy with PTV in infants and children was first performed in the 1970s [13,26].

Delivered tidal volume during PTV is affected by multiple factors, including inspiratory pressure, duration of inspiration, airway resistance, size of catheter, and lung compliance [25,27]. PTV is less efficient than ventilation through endotracheal intubation because up to one-third of oxygen flow delivered to the catheter tip passes up through the glottic opening and out the nose and mouth [24,27]. High pressure oxygen delivery systems are optimal to provide effective ventilation through the relatively narrow catheters used for PTV. However, low pressure systems (eg, self-inflating bag connected to the cricothyroidotomy catheter via a 3.0 mm internal diameter endotracheal tube adapter, 7.0 mm ID ETT adapter connected through a 3 cc syringe, (figure 2)) are sufficient in most patients if a high flow oxygen system is not available [2,11,28,29]. (See 'Equipment' below.)

In adults, PTV is typically accomplished using a 50 pounds per square inch (psi) (350 kPa) oxygen source and a 13- to 16-gauge over-the-needle catheter [3,24,30]. The catheter size (13- to 16-gauge) does not appear to substantially affect gas flow rates when using wall outlet oxygen because gas flows in a turbulent fashion under high pressure through these narrow catheters [28]. Large cannula (>4 mm), inserted via the Seldinger technique, enable ventilation with lower pressures in adults but require either a cuff or upper airway obstruction to prevent gas from escaping through the upper airway [11].

Lower driving pressures (25 to 35 psi [172 to 241 kPa]) are used in infants and younger children (under 12 years of age) in order to prevent barotrauma [13]. Smaller catheters (16- to 18-gauge) are typically placed due to the anatomic limitation posed by the cricothyroid membrane in the pediatric population. (See 'Anatomy' above.)

Once ventilation is established, exhalation through the transtracheal catheter is insufficient to prevent hyperinflation of the lungs. However, in most instances where PTV is used, the patient's airway remains sufficiently patent to permit exhalation through the nose and mouth [3,31]. In situations where complete airway obstruction exists, the clinician should use longer expiratory time and lower oxygen delivery pressure. In addition, chest rise and fall with inspiration and expiration should be carefully monitored. Diminished chest fall with expiration should lead to further reduction in respiratory rate, prolongation of expiratory time, and emergency chest radiography to look for signs of pulmonary barotrauma (see 'Performing transtracheal ventilation' below). Although evidence for effectiveness is limited, the Ventrain device promotes active expiration through the device itself and may be used in patients with complete airway obstruction proximal to the cricothyroid membrane while theoretically reducing the potential for barotrauma or pneumothorax [32]. It is a small, single-use, manually operated, inspiratory flow adjustable ventilation device that is attached to the cricothyrotomy catheter and is driven by a high-pressure oxygen source. It generates positive pressure during inspiration and active suction during expiration through a Bernoulli effect within the device.

PTV provides less efficient ventilation than endotracheal intubation. Because of the concern for carbon dioxide retention with PTV, the traditional approach has been to use it as a short term (eg, less than 45 minutes) temporizing airway measure [12]. However, when oxygenation is well maintained, even relatively high levels of hypercarbia may be well tolerated, thus permitting its use for many hours at a time [2,12,33]. Regardless, the clinician should still rapidly seek to definitively secure the airway in most patients who require PTV, especially in settings complicated by increased intracranial pressure (because hypercarbia worsens intracranial pressure) or complete upper airway obstruction (increased risk of barotrauma).

There is no risk of gastric dilatation with needle cricothyroidotomy and PTV. The flow of gas up the airway aids in the expulsion of secretions, minimizing the need for suction and preventing pulmonary aspiration [24,34].

Using a canine model, researchers showed that it is not necessary to induce paralysis when using PTV for emergency ventilation of a sedated patient [35].

INDICATIONS — The primary indication is inability to maintain the airway with noninvasive standard airway procedures (eg, bag-valve-mask ventilation, endotracheal intubation using direct and/or video laryngoscopy) or rescue procedures (eg, laryngeal mask airway).

The typical setting involves patients with pathologic processes that cause distortion of the upper airway anatomy, for example [3,36-38]:

●Airway obstruction by uncontrolled bleeding into the oral cavity and/or vomiting

●Severe maxillofacial trauma - blunt, penetrating, or associated with mandibular fracture

●Laryngeal foreign body that cannot be removed expeditiously

●Swelling of upper airway structures, examples include:

•Infection, like epiglottitis or Ludwig's angina

•Allergic or immunologic reaction, as from food allergy or hereditary angioedema

•Chemical or thermal burns to the epiglottis and upper airway

•Post-extubation glottic edema

CONTRAINDICATIONS

Absolute — Needle cricothyroidotomy with percutaneous transtracheal ventilation (PTV) is absolutely contraindicated when the airway is maintainable through noninvasive means.

In addition, needle cricothyroidotomy with PTV should not be performed when damage to the larynx, cricoid cartilage, or trachea preclude successful oxygenation and ventilation via a transtracheal catheter, for example:

●Laryngeal injury with known damage to cricoid cartilage (laryngeal fracture)

●Tracheal rupture

●Tracheal transection with distal tracheal retraction into the mediastinum

Relative — Several relative contraindications arise in situations where anatomic distortion increases the risk of airway complications or where excessive bleeding may be encountered during needle cricothyroidotomy and PTV as follows:

●Anterior neck swelling (eg, angioedema, hematoma) that obscures anatomical landmarks

●Anatomic anomalies or distortion of the larynx and trachea (eg, repaired tracheal anomalies, Hurler syndrome) (see "Mucopolysaccharidoses: Clinical features and diagnosis", section on 'Hurler syndrome')

●Bleeding disorder

However, in most instances, the benefit of securing an airway will outweigh the risk of performing needle cricothyroidotomy in these circumstances.

PRECAUTIONS

Complete upper airway obstruction — In routine use of percutaneous transtracheal ventilation (PTV) through a catheter, much of the expired air comes out of the mouth and nose. Thus, with complete upper airway obstruction, egress of expired air is difficult. Initial studies in animals suggested that PTV in the setting of complete upper airway obstruction led to development of massive distension of lungs, severe barotrauma, and death [39]. Subsequent studies have shown successful use of PTV in settings of complete upper airway obstruction using modified techniques that consist of prolonged expiratory time, larger internal diameter catheters, and lower oxygen flow rates [40-42].

PTV may be used successfully in partial laryngeal obstruction as the "ball-valve" effect, while constraining natural inspiration, adequately permits exhalation [15,30,31,43]. For infants and young children with complete upper airway obstruction and where other methods have been unsuccessful, it is reasonable to use PTV. Ventilatory methods should use a longer expiratory time (eg, I:E ratio of 1:8 to 1:10), lower oxygen delivery pressure and flow rate, and as large a catheter as possible. In addition, the clinician should carefully monitor for chest rise and fall with inspiration and expiration. Diminished chest fall with expiration should lead to further reduction in respiratory rate, longer expiratory time, and emergent chest radiography to look for signs of pulmonary barotrauma. (See 'Performing transtracheal ventilation' below.)

PREPARATION

Evaluation — Needle cricothyroidotomy with percutaneous transtracheal ventilation (PTV) is an invasive emergent airway procedure that is life-saving, albeit with significant potential morbidity. Thus, proper patient selection is essential. The key indication consists of inability to maintain a patient's airway utilizing noninvasive means (eg, bag-valve-mask ventilation, endotracheal intubation, laryngeal mask airway). These patients cannot be intubated and cannot be ventilated.

Proposed criteria include [12]:

●Inability to maintain adequate oxygenation with bag-valve-mask ventilation using 100 percent oxygen

and

●Inability to place or utilize a laryngeal mask airway

and

●Inability to endotracheally intubate (eg, three or more failed attempts or failure to intubate after 10 minutes in a patient who cannot be maintained with bag-valve-mask ventilation or other noninvasive device)

Pathologic processes that cause distortion of the upper airway anatomy comprise the typical scenarios. (See 'Indications' above.)

The presence of subcutaneous emphysema in the neck may indicate tracheal or cricoid injury and is typically a contraindication to the use of this procedure as is transection of the trachea with retraction of the distal end into the mediastinum. (See 'Contraindications' above.)

Special precautions are needed for infants and young children with complete upper airway obstruction, as in the case of a tight foreign body obstructing the larynx. (See 'Complete upper airway obstruction' above.)

Patient counseling/informed consent — Needle cricothyroidotomy with percutaneous transtracheal ventilation is usually an emergent procedure that does not allow for patient counseling/informed consent prior to the procedure. However, the procedure's necessity, benefits, and risks should be explained to the patient and/or caretaker at the earliest possible time after completion. If feasible, it is ideal for a member of the team not directly involved with the resuscitation to explain the procedure to the family as it is being done.

Equipment — Needle cricothyroidotomy and percutaneous transtracheal ventilation can be performed using standard materials readily available in any hospital. Commercial setups are also attainable [3,12,44,45]. To ensure maximum effectiveness in a highly stressful emergent setting, the author recommends that equipment for PTV, including all the necessary components, be organized and readily available [46].

General equipment

●Universal precautions (gown, cap, mask, eye protection, sterile gloves)

●Povidone iodine for site cleansing

●Sterile drape

●One percent lidocaine without epinephrine in syringe for injection of local anesthesia in the conscious or semi-conscious patient (see 'Analgesia and sedation' below)

●Three to 10 mL syringe filled with sterile saline

Catheter (large bore) — AVOID needleless safety catheters that cannot be connected to a syringe (eg, BD InSyte, Autogard) [13,47]. Ensure that such "non-safety" catheters are easily available and are a part of the cricothyroidotomy kit. Similar catheters are also used for needle aspiration of pneumothorax (needle thoracocentesis).

●Infants and young children – 16- to 18-gauge IV catheters

●Adults and adolescents – 12- (ID 2.8 mm) to 16-gauge (ID 1.5 mm) IV catheters (angiocath) or 6 French transtracheal catheter (2 mm ID) [3]

●Alternative catheters include vessel dilators from central line kits (5 to 7 French for younger children and 7 to 9 French for adults), a catheter introducer, or a commercially available cricothyroidotomy catheter (eg, Acutronic, Quicktrach baby) [16,42,48,49].

Bag-valve-mask connector options — If a bag-valve-mask will be used for patient ventilation, then it should connect to the catheter using one of the following improvised adapters:

●Three mL Luer lock syringe with plunger removed with 7.5 mm ID endotracheal tube connector (bag-valve-mask connector) (figure 2)

●3.0 mm ID endotracheal tube connector attached directly to the catheter (figure 2) (bag-valve-mask connector)

●2.5 mm ID endotracheal tube connector attached to cut off IV tubing with Luer lock end connected directly to the catheter (figure 3)

Oxygen tubing connector options — If oxygen tubing will be used to connect to the oxygen source, then the clinician may use one of the following options:

●Direct connection of oxygen tubing to catheter (figure 4)

●Y connector (oxygen tubing) (figure 4)

●Three-way stopcock (oxygen tubing) (figure 5)

High pressure oxygen source — One of the following oxygen sources is recommended:

●Hospital wall outlet without a regulator or set at the maximum flow rate of 15 L/minute which provides oxygen at 58 psi (400 kPa, 4 atmospheres) for adolescents and adults; for younger children use a maximum flow rate of 10 to 12 L/minute which provides oxygen at 25 to 35 psi (172 to 241 kPa, 1.7 to 2.4 atmospheres) [3,11]

●Oxygen tank without interposing a flow valve with flow rates as per a hospital wall outlet [11]

●Flush valve of a mechanical ventilator

DO NOT USE the common gas outlet of the anesthesia machine, as most machines have a pressure limiting valve on the back bar which opens at 5 psi (35 kPa) [50].

Oxygen tubing or equivalent — The tubing must be capable of withstanding high pressure.

Manual in-line valve — The setup must control intermittent flow of oxygen and ventilate the patient, examples include:

●A permanent, commercially available system (figure 6) (eg, by Instrumentation Industries, Inc.)

●A temporary system using Y-connector, side port cut into oxygen tubing, three-way stopcock, or catheter adapter with bag-valve-mask (figure 4 and figure 5 and figure 2 and figure 3) [25,28,29,51]

PROCEDURE — Percutaneous transtracheal ventilation is summarized in the table (table 1 and figure 7).

General considerations — Place the patient in the supine position on the stretcher. Unless there is a cervical spine injury (known or suspected), extend the patient's neck to help identify the procedural landmarks and to obtain the widest exposure of the cricothyroid membrane. While assembling the equipment for the procedure, ask an assistant (preferably the respiratory therapist) to preoxygenate the patient by administering high-flow oxygen via face mask if the patient is breathing spontaneously or via bag-valve-mask if not.

Site verification — The clinician should locate the cricothyroid membrane by palpating the prominence of the thyroid cartilage in older children, adolescents, and adults and moving the finger inferiorly into the depression between the thyroid and cricoid cartilages.

In infants and young children, the clinician should palpate the trachea just above the suprasternal notch and move superiorly until the prominence of the cricoid cartilage is felt. The needle should be placed just above the cricoid cartilage in the midline. If the cricothyroid membrane cannot be located with certainty in an infant or a young child, percutaneous transtracheal ventilation (PTV) can be safely performed by introducing the needle between the tracheal cartilages [13]. (See 'Anatomy' above.)

Regardless of technique or patient age, manual palpation of the cricoid membrane is often inaccurate in children [52]. Although not studied in children, investigators have demonstrated the ability to accurately and rapidly identify the cricothyroid membrane in adult cadavers and live patients using bedside ultrasonography [21]. This may be done just prior to the procedure or electively before intubation in high risk cases, if time permits [53,54]. Bedside ultrasonography is especially relevant in those with difficult neck anatomy, and in adult female subjects because it is more difficult to identify cricothyroid membrane in females when compared to males irrespective of body habitus [55].

Analgesia and sedation — Under emergent circumstances there may not be time to administer sedative or analgesic medications. The most important goal is to secure the airway. In the case of respiratory depression or arrest, sedation may make matters worse and is not advised. However, if the patient is agitated and struggling and this behavior is impeding the progress of the procedure, a sedative and analgesic can be given to help control the patient.

Paralysis or subsequent continuation of paralysis may be considered based on the patient's response to the procedure and adequacy of ventilation achieved. In canine studies, PTV without paralysis has been achieved in sedated animals with unobstructed airways [35].

Skin preparation — Prepare the skin of the anterior neck with an antiseptic solution (eg, povidone-iodine). If time permits, anesthetize the skin, subcutaneous tissues, and the cricothyroid membrane with a local anesthetic such as 1 percent lidocaine administered through a 27- or 30-gauge needle.

Monitoring — Monitor heart rate and rhythm, blood pressure, respiratory rate, and oxygen saturation throughout the procedure. Lower the patient's gown and sheet to observe the rise and fall of the chest with respiration. Capnography should be used as feasible both during the procedure (to ensure intratracheal location of the needle or the catheter) and during patient ventilation [30,56].

Once the catheter is in place and percutaneous transtracheal ventilation is established, the site of needle cricothyroidotomy should be observed closely for any kinking or dislodgement of the catheter, subcutaneous emphysema (may indicate dislodgment of the cannula), or bleeding [3]. Chest radiographs should be obtained to ensure that the lungs are not over-expanded. Adequacy of PTV should be assessed using clinical parameters as well as frequent blood gas analysis.

Technique

Needle cricothyroidotomy — The technique is shown in the figure (figure 7) and described below:

●Needle cricothyroidotomy should be performed with universal precautions and sterile technique. The puncture site is cleansed with povidone-iodine solution after sterile gloves have been donned.

●Hold the trachea in place and provide skin tension with the thumb and middle finger of the non-dominant hand placed on either side of the trachea. Use the index finger to palpate the cricothyroid membrane.

●Hold a 3 to 10 mL syringe half-filled with saline attached to the over-the-needle IV catheter in the dominant hand.

●Place the catheter in the midline of the neck at the inferior margin of the cricothyroid membrane (to avoid the cricothyroid blood vessels located superiorly and laterally). Direct it caudally (toward the feet) at an angle of 30 to 45 degrees.

●Puncture the skin and subcutaneous tissue. Advance the catheter while continuously applying negative pressure on the syringe, until air bubbles are seen, confirming intratracheal placement.

●Advance the catheter forward off the needle until its hub rests at the skin surface. Remove the syringe and the needle.

●Reattach the syringe to the catheter and again aspirate for air to confirm that the catheter remains in the trachea.

●Hold the catheter firmly in place at all times or delegate an assistant to do this to reduce the chance of kinking or dislodgement, even after it has been secured with suture material.

Performing transtracheal ventilation

●Connect the catheter to high pressure tubing (connected to a valve and a source of 100 percent oxygen) or to a bag-valve-mask (figure 2 and figure 3 and figure 4 and figure 5). (See 'Bag-valve-mask connector options' above and 'Oxygen tubing connector options' above.)

●Give a few ventilations to reconfirm placement and ensure that the equipment is functioning properly.

●Fix the catheter in place with a suture or a tracheostomy tie, as possible.

●Interpose a capnometer in the circuit to monitor end tidal CO₂, if possible.

●Begin regular ventilation by intermittently opening and closing the in-line valve (figure 6); by intermittently occluding the side port, y-connector, or stopcock (figure 4 and figure 5); or by ventilations with the self-inflating resuscitation bag, depending on the system in use.

●Use I:E ratio of 1:4 to 1:5, with a breath rate of 10 to 12/minute for most children. Change the ratio to 1:2 to 1:3 with a breath rate of 15 to 20/minute in the setting of increased intracranial pressure to improve CO₂ elimination. With partial or complete upper airway obstruction, use the ratio of 1:8 to 1:10 with a breath rate of 5 to 6/minute to reduce the risk of pulmonary barotrauma. Adjust these ratios based on clinical monitoring, blood gas measurements, and chest radiography.

●Stand clear and observe universal precautions as oropharyngeal secretions may sometimes be expelled through the patient's mouth and nose with great force.

Transtracheal ventilation through a cricothyrotomy may be performed using the Ventrain device although experience in children and availability of the device is limited [32]. The Ventrain device has the advantage of promoting expiration through the device itself, which permits use in patients with complete airway obstruction proximal to the cricothyroid membrane while theoretically reducing the potential for barotrauma or pneumothorax.

Cricothyroidotomy may also be performed rapidly and effectively using a modified Seldinger technique (wire-guided or catheter-over-needle technique). (See "Emergency cricothyrotomy (cricothyroidotomy) in adults", section on 'Seldinger technique'.)

COMPLICATIONS — Barotrauma and catheter issues that prevent transtracheal ventilation are the two most commonly described complications of percutaneous transtracheal ventilation (PTV) (table 2) [3,12,13,15,16,24]:

●Subcutaneous emphysema can develop during cricothyroidotomy, securing of the catheter, PTV, or after removing the catheter [3,15,57]. Kinking or dislodgement of the transtracheal catheter may result in rapid accumulation of subcutaneous gas in the tissues. In addition, multiple attempts at catheter placement may allow gas to escape into the tissues from previous puncture sites. Techniques to prevent the development of subcutaneous emphysema include:

•Using kink-resistant Teflon catheters

•Assigning an individual to hold the catheter hub

•Utilizing a commercially available cricothyroidotomy catheter with attached flanges for securing the catheter (avoids kinking and misplacement)

•Placing a fingertip firmly over the puncture site and applying pressure for a few minutes to prevent air leak after catheter removal

Subcutaneous emphysema after PTV typically resolves without intervention [3].

●Pulmonary barotrauma may arise from an overly high respiratory rate that leads to insufficient time for passive exhalation and can cause lung hyperinflation, pneumothorax, and pneumomediastinum. These complications may also cause diminished venous return to the heart resulting in reduced cardiac output and/or hypotension [2,3,14,24,58]. Pulmonary barotrauma is more likely in the setting of complete upper airway obstruction. Very slow breath rates (eg, 5 to 6 breaths/minute) and very long expiratory time (eg, I:E ratio of 1:8 to 1:10) are recommended to avoid barotrauma in this setting.

●In one series, PTV could not be accomplished in 6 of 29 (21 percent) emergency patients who required a rescue airway because of poor landmarks, catheter kinking, or inability to place the catheter in the trachea [3]. Proper training and the use of Teflon or commercially available cricothyroidotomy catheters are potential ways to improve the success rate for PTV. One study has described an easily made model for teaching cricothyroidotomy to medical personnel using readily available materials in any operating room like a plastic tray, standard plastic breathing tubing, tape, and gauze [59].

Other less common complications of needle cricothyroidotomy and PTV include damage to adjacent structures, bleeding, and infection (table 2) [12,57,58,60]. Although pulmonary aspiration may occur during PTV, in a canine model, it provided significant protection from aspiration relative to dogs with unprotected airways [34].

FOLLOW-UP CARE — Prolonged percutaneous transtracheal ventilation (PTV) is associated with excessive inspiratory workload, hypercapnia, barotrauma, and catheter dislodgement with subcutaneous emphysema [3,5,12,61]. Thus, a definitive airway (ie, endotracheal tube or tracheostomy) should be obtained as soon as possible after PTV is established. Emergent anesthesiology and otolaryngology consultation may be required, especially in patients with traumatic injury to the face and/or neck.

In non-traumatic cases, intubation, with direct laryngoscopy, video laryngoscopy, or guided by endoscope, is successful in the majority of cases. Subsequent intubation may be easier as the high tracheal pressure from expiratory gases tends to open the previously collapsed glottis, improving visualization of the glottic opening. In addition, there is reduced operator stress and more time to visualize, and if needed, suction the glottic opening [3,62].

SUMMARY AND RECOMMENDATIONS

●Needle cricothyroidotomy – Needle cricothyroidotomy involves passing an over-the-needle catheter through the cricothyroid membrane (figure 2). Needle cricothyroidotomy may be performed on patients of any age but is preferable to surgical cricothyroidotomy in infants and children up to 10 to 12 years of age because it is anatomically easier to perform with less potential damage to the larynx and surrounding structures. (See 'Needle cricothyroidotomy' above.)  

●Percutaneous transtracheal ventilation – Percutaneous transtracheal ventilation (PTV) is the delivery of oxygen to the lungs through an over-the-needle catheter using an improvised ventilation device. For this topic, PTV refers to use of a self-inflating ventilation bag or wall oxygen as the delivery source. (See 'Percutaneous transtracheal ventilation' above.)

●Indications – The primary indication for needle cricothyroidotomy with PTV is inability to maintain the airway with noninvasive standard airway procedures (eg, bag-valve-mask ventilation, endotracheal intubation) or rescue procedures (eg, laryngeal mask airway). (See 'Indications' above.)

●Contraindications – Needle cricothyroidotomy with PTV is absolutely contraindicated when the airway is maintainable through noninvasive means. (See 'Contraindications' above.)

In addition, needle cricothyroidotomy with PTV should not be performed when damage to the larynx, cricoid cartilage, or trachea preclude successful oxygenation and ventilation via a transtracheal catheter. (See 'Contraindications' above.)

●Anatomy – The key anatomic landmarks are (from cephalad to caudad): hyoid cartilage, thyroid cartilage, cricothyroid membrane, cricoid cartilage, and the tracheal rings (figure 1). (See 'Anatomy' above.)

●Preparation – Needle cricothyroidotomy and percutaneous transtracheal ventilation (PTV) can be performed using standard materials readily available in any hospital (figure 2 and figure 3 and figure 4 and figure 5 and figure 6). Commercial setups are also available. To ensure maximum effectiveness in a highly stressful emergent setting, the equipment for PTV, including all the necessary components, should be organized and immediately available. (See 'Preparation' above.)

●Procedure – The tables and figure summarize the procedure (table 1 and figure 7) and potential complications (table 2) for needle cricothyroidotomy with PTV. (See 'Preparation' above and 'Procedure' above and 'Complications' above.)