Chapter 20. Double Lumen Airway Tube Intubation

The Esophageal-Tracheal Combitube (ETC; Kendall Sheridan, Mansfield, MA) and the EasyTube (EzT; Teflex Medical [Ruesch], Kernen, Germany) are double lumen airway devices that can be blindly inserted into the unconscious and unresponsive patient. The ETC and EzT function to adequately ventilate and oxygenate a patient while simultaneously protecting the airway from aspiration.1,2 They are most often used in the prehospital setting by emergency medical technicians not trained in standard orotracheal intubation and by paramedic-level rescuers as an alternative airway device when standard orotracheal intubation fails.3–5 These are the only two double lumen devices used in the prehospital setting and the Emergency Department. The Emergency Physician should be familiar with these devices so that it can be removed and exchanged with an endotracheal tube if placed in the prehospital environment or if required in the Emergency Department to manage a difficult airway.

The ETC is a double-tube, double lumen, and double-cuffed device (Figure 20-1). The ETC starts as two distinct tubes that fuse into one, but remain functionally separated by a partition. The shorter clear tube is continuous with the distal open port, also known as the tracheoesophageal lumen. At its distal end is the distal tracheoesophageal cuff, similar to that of an endotracheal tube. It is a high-volume, low-pressure balloon that is inflated through the white inflation port. The longer blue tube is continuous with the eight perforations known as the proximal ports. A large pharyngeal cuff is just proximal to the perforations. This cuff is positioned between the base of the tongue and the palate, separating the oral and nasal cavities from the remainder of the airway. It is inflated through the blue inflation port.

The EzT is also a double-tube, double lumen, and double-cuffed device with a structure similar to the ETC (Figure 20-2). However, it has several differences in comparison to the ETC. First, the shorter clear tube ends as a conventional single lumen 7.5 mm endotracheal tube. Second, the longer blue tube ends in an open aperture, rather than multiple perforations. Third, the EzT is latex free.6

Both the ETC and EzT may be inserted blindly into a patient's airway. If the distal tip enters the trachea, the patient is ventilated through the shorter clear tube and the distal cuff prevents aspiration of gastric contents into the trachea. If the distal tip enters the esophagus, the patient is ventilated through the longer blue tube, whose proximal ports lie in the hypopharynx, while the distal cuff will occlude the esophagus.

The EzT may also be used as a primary airway device under direct laryngoscopy. When placed successfully into the trachea, it functions as a 7.5 mm endotracheal tube. If unable to pass it into the trachea, it can be advanced into the esophagus and the patient ventilated through the blue tube.6,7

Both devices are available in two sizes. The 37 French SA model of the ETC is meant for small adults. The manufacturer recommends its use in patients with a height of 122 to 168 cm (4.0 to 5.5 ft). The 41 French model of the ETC is meant for larger adults with a height of 152 cm (5 ft) and greater. Patients in the intermediate range of 152 to 168 cm (5.0 to 5.5 ft) can use either model. A recent study demonstrated that the 37 French SA model can be used in patients up to 183 cm (6 ft, 1 in) in height. The EzT is available in a 28 French model for patients with a height from 90 to 130 cm (3.0 to 4.3 ft) and a 41 French model for patients over 130 cm (4.3 ft).

Several attributes specific to these devices contribute to their usefulness in the acute setting. Both are effective as either a primary or backup airway management device. A patient can be ventilated with the tip positioned in either the esophagus or the trachea. Minimal training is necessary. There is no need for a laryngoscope. They are easily inserted with patient's head and neck in a neutral position. The dual lumens and balloons also offer certain advantages. When placed in the esophagus, the distal lumen of both allow for gastric suctioning. The proximal lumen of the EzT is an open lumen rather than perforations as in the ECT. This allows for the passage of a suction catheter, fiberoptic scope, or endotracheal tube changer (maximum diameter 3.99 mm) into the trachea.6 The balloons firmly secure the device, making dislodgment unlikely. The proximal balloon can functionally tamponade oropharyngeal bleeding and serve to minimize the risk of aspirating oral debris.8 These attributes make these devices suitable for rescuers of all skill levels.

The primary indication for an ETC or an EzT is as a backup device for airway management in and out of the hospital. It can be used for difficult or failed orotracheal intubations. It should be placed on crash carts for use by individuals not skilled with orotracheal intubation. In situations with limited access to the patient's head (e.g., extrication situations), they can be used where standard orotracheal intubation cannot be performed. They should be considered in situations of potential cervical spine injury as the device can be inserted with the patient's head and neck in a neutral position. The ETC is an appropriate device for management of the airway when visualization is limited due to bleeding or secretions. All Emergency Physicians should become familiar with these devices if they are used by emergency medical technicians in their region as well as considering it as an alternative airway device for difficult airways in the Emergency Department.8,9

Certain contraindications exist and should be addressed. These devices should not be used on patients with an intact gag reflex. If intubation is anticipated, there should be enough time to premedicate the patient and induce anesthesia before inserting them. Size limits apply to both the ETC and the EzT. The standard ETC cannot be used in patients under 5 feet tall. The smaller ETC SA model cannot be used in patients under 4 feet tall. The EzT cannot be used in patients under 3 feet tall. The ETC cannot be used in patients with a latex allergy. The EzT is latex free and can be used in all patients.

Their use is contraindicated if the patient has known esophageal disease or an airway obstruction. Patients with known esophageal disease (e.g., strictures, cancer, or victims of caustic ingestions) are at an increased risk of complications such as perforation and failed performance of the device. Patients with known upper airway obstruction (e.g., secondary to congenital disorders, cancer, or other anatomic abnormalities) are also at increased risk for complications and performance failure.

• Gloves, gown, and mask
• Eye protection, goggles or a face mask with an eye shield
• Pulse oximeter
• Noninvasive blood pressure cuff
• Cardiac monitor
• IV access equipment
• ETC or EzT kit
• Oxygen source and tubing
• Suction source and tubing
• Water-soluble lubricant
• Bag-valve-mask device
• Advanced Cardiac Life Support equipment and medications
• Surgical airway equipment

The ETC and the EzT are prepackaged in a kit form with the dual lumen airway tube, two syringes for balloon inflation, a 90° elbow, and a flexible suction catheter (Figures 20-3A & B). The ETC kit also contains a vomit deflector that is not routinely used, as it may be associated with significant complications and gastric contents directed at the healthcare professional. The suction catheter included is designed to be inserted through the smaller tube and to exit the tracheoesophageal port.

Preoxygenate the patient with a bag-valve-mask device using 100% oxygen. Establish IV access. Apply the pulse oximeter, noninvasive blood pressure cuff, and the cardiac monitor. Place the patient in the supine position, or in any position that may be required. The neutral position is not required. Prepare the equipment while an assistant is ventilating the patient. Remove the ETC or EzT and equipment from the package. Attach the syringes to their respective ports and inflate the cuffs (Figure 20-4). If a leak of air is present or if the cuff does not inflate properly, discard the device and open another kit. Deflate the cuffs and leave the syringes attached to the ports. Liberally lubricate the tip of the device with a water-soluble lubricant.

Insert the thumb of the nondominant hand into the patient's mouth and over their tongue (Figure 20-5A). Place the nondominant fingers under the chin. Depress the tongue and open the jaw simultaneously. Remove any dental devices and foreign bodies. Grasp the device with the dominant hand. The curve of the device should be in the same direction as the natural curve of the pharynx. Insert the device into the midline of the patient's mouth. Advance it in a downward curved motion until the patient's teeth or alveolar ridge lies between the two printed bands of the ETC (Figure 20-5B) or the black stripe of the EzT (Figure 20-6). Do not insert the device forcefully as significant injury can occur. If it does not advance easily, redirect it and then reinsert the device. Inflate the pharyngeal cuff with the volume of air marked on the blue port (100 mL for the ECT, 85 mL for the ECT SA, or 80 mL for the EzT). The device will withdraw slightly from the patient's mouth as the pharyngeal cuff is inflated. Inflate the distal cuff with the volume of air marked on the white port (15 mL for the ECT, 12 mL for the ECT SA, or 10 mL for the EzT).

Because most blind intubations are esophageal, begin ventilation through the longer blue tube (Figures 20-5C & 20-6). Auscultation of breath sounds, symmetric rise of the chest, fogging in the tube for more than six breaths, and lack of gastric insufflation confirm placement within the esophagus and ventilation through the proximal ports/aperture (Figures 20-5C & 20-6). If no breath sounds are auscultated and gastric insufflation occurs, the trachea is intubated (Figure 20-5D). Begin ventilation through the shorter clear tube and verify by auscultation the presence of breath sounds.

If breath sounds cannot be auscultated when ventilating through either tube, the device may be too far into the pharynx. Deflate the pharyngeal cuff and withdraw the device 2 to 3 cm. Reinflate the pharyngeal cuff. Ventilate through the longer tube and confirm tube placement as noted above.

Secure the device. This is accomplished using the standard method of taping or a commercially available endotracheal tube holder. Although there are reports of short-term (e.g., 4 to 6 hours) ventilator use with these devices, it should be replaced with a standard endotracheal tube for long-term ventilation.10

Several methods for replacing the device are available. The first is to remove the device entirely and intubate the patient orotracheally. Deflate the pharyngeal cuff. Suction the patient's mouth and oropharynx. Tilt the device to the left side of the patient's mouth. Deflate the distal cuff. Remove the device. Intubate the patient orotracheally.11

Alternative methods of intubation are also possible. Deflate the pharyngeal cuff. Suction the mouth and oropharynx. Tilt the device to the left side of the patient's mouth. Insert the laryngoscope and visualize the tip of the device. If it is in the esophagus, orotracheally intubate the patient, deflate the distal cuff of the device, and remove the device. This method will prevent aspiration, especially if endotracheal intubation is unsuccessful. If it is in the trachea, instruct an assistant to deflate the distal cuff of the device and remove it slowly. After the device clears the patient's vocal cords, immediately insert the endotracheal tube.

The EzT has a significant advantage over the ECT when attempting to replace it with a conventional endotracheal tube. If the distal end is in the trachea and the patient is being ventilated through the short clear tube, it can be left in place as it is functioning as a 7.5 mm endotracheal tube. If the distal end is in the esophagus and the patient is being ventilated through the long blue tube, a fiberoptic scope or an endotracheal tube changer can be passed through the blue tube and into the trachea. The EzT can then be removed and an endotracheal tube passed over the endotracheal tube changer. This cannot be done with the ECT because it has perforations rather than an open aperture.6,7

Despite the potential utility of the ETC or EzT in the acute setting, several disadvantages must be kept in mind. These include the high cost, bulky packaging, and the fact that the ETC detachable “vomit deflector” can expose providers to gastric contents if improperly managed. It is best not to use the vomit deflector, as it can be associated with aspiration. Several risks are also inherent to the insertion and mechanics of the devices. It should be recognized that the presence of a rigid cervical collar can cause great difficulties in the proper placement of this device.12 The device is most frequently inserted into the esophagus. Therefore, there is a risk of esophageal injury.13 There is no way to suction the trachea with the open distal port in the esophagus. It is important to note that resuscitation drugs that can be routinely given through an endotracheal tube cannot be given through the device positioned with the tip in the esophagus. Drugs will accumulate in the blind end of the tube or the hypopharynx. Significant soft tissue injury can occur due to the tip of the device or if the balloons contain too much air.12,14 If forced, the tip can perforate the esophagus, piriform sinus, or vallecula. The increased cuff pressure of the ETC versus the EzT can result in mucosal injury.15 An overinflated distal balloon located in the esophagus can compress the trachea and cause an airway obstruction.16 Always inflate the balloons with the recommended volume of air and not more. Prolonged use of up to 4 hours can result in the proximal cuff obstructing the lingual veins and resultant tongue engorgement.17 This can result in a difficult intubation when exchanging the device for an endotracheal tube.

The Esophageal-Tracheal Combitube and the EasyTube can adequately ventilate a patient whether it is placed in the esophagus or trachea. It is relatively simple to use and requires minimal training. It offers an additional technique for emergency care providers to secure the airway in both the prehospital and hospital environment. It should be included in every armamentarium dedicated to the difficult airway.