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Emergency Medicine Procedures, 2e

Chapter 23. Retrograde Guidewire Intubation

Introduction
Failure to establish a definitive airway is a significant cause of death and disability among emergency patients. Oral endotracheal intubation via direct
laryngoscopy, increasingly often video­assisted, remains the “gold standard” of airway management. Difficult situations arise in which oral
endotracheal intubation is impossible, is contraindicated, or fails. Retrograde guidewire intubation is an alternative airway management technique
that should be familiar to those involved with emergency airway management.1

Retrograde intubation was first described in 1960 by Butler and Cirillo.2 In 1963, Waters described insertion of an epidural catheter through a
cricothyroid puncture as an alternative means of establishing an airway.3 Powell and Ozdil reported a series of 15 patients in whom retrograde
intubation was employed without complications using a plastic catheter rather than an epidural catheter as a guide into the trachea.4 The current
technique of retrograde intubation varies little from these original descriptions.

Retrograde intubation represents one of several alternative maneuvers for securing the difficult airway. While mouth tumors, cervical
arthritis, and jaw ankylosis represent rare cases of difficult­to­control airways, maxillofacial trauma continues to represent the most common
indication for alternative airway management. Retrograde intubation has proven to be an effective method used by Emergency Physicians and
prehospital personnel to establish an airway.

Completion times for retrograde intubation vary based on physician experience. Among healthcare professionals who had no prior experience with
the technique but who had just completed a mannequin­aided training course, the mean length of time to intubation was 71 ± 4 seconds.1 In a second
study involving resident physicians after a brief instruction course, 36 of 40 residents (90%) completed retrograde intubation within 150 seconds, with
a mean intubation time of 56 ± 6 seconds.10

Indications
The American Society of Anesthesiologists defines a difficult airway as the clinical situation in which a conventionally trained Anesthesiologist
experiences difficulty with mask ventilation, difficulty with tracheal intubation, or both.5 Retrograde intubation, among other invasive back­up
techniques such as cricothyroidotomy, should be considered in any patient in whom endotracheal intubation may be difficult, is
contraindicated, or has failed. It is potentially indicated when airway control is required and less invasive methods have failed. Maxillofacial
trauma and cervical spine fractures represent the most common etiologies of a difficult airway.6 In one report of 19 patients with either maxillofacial
trauma or fractures of the cervical spine, six had prior, failed orotracheal intubation attempts. In all of these patients, retrograde intubation was
successful on the first attempt.6 Jaw ankylosis, cervical arthritis, mouth tumors, and muscular dystrophy represent less common but equally
challenging airway situations.4,7

Another clinically important situation arises when a patient presents with impending ventilatory failure. While retrograde intubation is generally a
longer procedure than orotracheal intubation, oxygenation and ventilation can be maintained with a bag­valve­mask device during the procedure. It is
useful when bleeding obstructs visualization of the glottis.

A less common indication includes retrograde intubation of a difficult airway in a patient being ventilated with a laryngeal mask airway. This indication
exists because withdrawal of the laryngeal mask airway over a blindly placed catheter can result in dislodgement of the catheter, necessitating
replacement of the laryngeal mask airway.8

Contraindications
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control the airway with less invasive techniques. Other
contraindications include an anterior neck mass, infections, or cancerous process overlying the cricothyroid membrane. Trismus, or the inability to
open the mouth, is a contraindication to this technique. Apneic patients who cannot be ventilated with a bag­valve­mask device should receive a
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A less common indication includes retrograde intubation of a difficult airway in a patient being ventilated with a laryngeal mask airway. This indication
exists because withdrawal of the laryngeal mask airway over a blindly placed catheter can result in dislodgement of the catheter, necessitating
replacement of the laryngeal mask airway.8

Contraindications
The major contraindication to retrograde intubation is the ability to control the airway with less invasive techniques. Other
contraindications include an anterior neck mass, infections, or cancerous process overlying the cricothyroid membrane. Trismus, or the inability to
open the mouth, is a contraindication to this technique. Apneic patients who cannot be ventilated with a bag­valve­mask device should receive a
cricothyroidotomy and not a retrograde guidewire intubation. Those unfamiliar with the equipment and/or technique should not attempt this
procedure. While one case report presents the successful use of a mannequin to teach retrograde intubation to emergency caregivers, familiarity with
the procedure is required for optimum patient management.1

Equipment
68 to 80 cm spring guidewire with a J tip
16 to 18 gauge catheter­over­the­needle (angiocatheter)
Endotracheal tubes, various sizes
Sterile saline
10 mL syringes
18 gauge needles
Hemostats, 2
Magill forceps
Sterile drape
20 mL syringe
Povidone iodine or chlorhexidine solution
Face mask
Bag­valve device
Oxygen source and tubing
Suction source and tubing
Yankauer suction catheter
1% lidocaine
4% viscous lidocaine (optional)
Spray anesthetic (lidocaine or benzocaine)
Tape (or a commercially available endotracheal tube holder)

Retrograde guidewire intubation can be performed using a standard commercial retrograde intubation kit (Cook Retrograde Intubation Set, Cook
Incorporated, Bloomington, IN). It consists of an 18 gauge needle set, 68 to 80 cm spring guidewire, and an 11 French introducer catheter (Figure 23­
1). The remainder of the material must be supplied as listed above.

Figure 23­1.

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Incorporated, Bloomington, IN). It consists of an 18 gauge needle set, 68 to 80 cm spring guidewire, and an 11 French introducer catheter (Figure 23­by:
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1). The remainder of the material must be supplied as listed above.

Figure 23­1.

The retrograde guidewire intubation kit.

Patient Preparation
If time permits, and the patient is aware of pain, anesthetize the airway. Nebulized viscous lidocaine will anesthetize the airway in 15 to 20 minutes.
Alternatively, inject 2 mL of 1% lidocaine percutaneously through the cricothyroid membrane and into the trachea.6 This may cause the patient to
cough and gag, with the subsequent possibility of aspiration. Lidocaine or benzocaine may be sprayed into the pharynx. An alternative anesthetic
method includes a superior laryngeal nerve block.9 Refer to Chapter 21 for details regarding this nerve block.

Clean the patient's neck of any dirt and debris. Identify, by palpation, the hyoid bone, thyroid cartilage, cricoid cartilage, and cricothyroid membrane.
Apply povidone iodine to the patient's neck, followed by sterile drapes.

Technique

The procedure is relatively simple in theory but difficult to perform “in the heat of battle.”1,10–13 Prepare the equipment. Place the 16 to 18 gauge
catheter­over­the­needle onto a 10 mL syringe containing 3 to 5 mL of sterile saline. Select an appropriate size endotracheal tube for the patient. Check
the integrity of the cuff. Lubricate the inside and outside of the distal tip of the endotracheal tube liberally. Open the retrograde guidewire kit and/or
assemble all equipment. The equipment should be preassembled, prepackaged, sterilized, and stored in an easily accessible site.

Stabilize the patient's larynx with the thumb and middle finger of the nondominant hand (Figure 25­2). Identify the cricothyroid membrane with the
index finger of the nondominant hand. Leave the index finger on the cricothyroid membrane. Infiltrate lidocaine subcutaneously over the cricothyroid
membrane if the patient is awake to minimize discomfort from the percutaneous catheter insertion. Insert the 16 to 18 gauge catheter­over­the­needle
guided along the index finger, at a 20° to 30° angle upward and through the cricothyroid membrane (Figure 23­2A). Although not recommended,
some physicians prefer to use the needle without the catheter. The sharp needle within the trachea can cause significant injury when compared to the
soft catheter. Care should be taken to puncture the cricothyroid membrane just above the cricoid cartilage to avoid injury to the
cricothyroid arteries. The loss of resistance signifies that the needle is in the larynx. Aspirate air through the saline­filled syringe to confirm
correct needle placement (Figure 23­2A). Advance the catheter until the hub is against the skin. Remove the needle and syringe, leaving the
catheter pointed upward and through the cricothyroid membrane. If this has not already been done and the patient is awake, inject 2 mL of 1%
lidocaine through the catheter to anesthetize the airway.

Figure 23­2.

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catheter pointed upward and through the cricothyroid membrane. If this has not already been done and the patient is awake, inject 2 mL of 1%Provided by:
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lidocaine through the catheter to anesthetize the airway.

Figure 23­2.

Retrograde guidewire intubation. A . A syringe containing saline is attached to the catheter­over­the­needle. The catheter­over­the­needle is inserted
through the cricothyroid membrane. The air bubbles in the syringe indicate air aspirated from the trachea. For clarity, the physician's hand and fingers
stabilizing the airway and identifying the cricothyroid membrane are not seen in this illustration. B . The needle and syringe have been removed and
the catheter remains. The guidewire is fed through the catheter and out the patient's mouth. C . The distal guidewire is clamped with a hemostat as it
exits the skin of the neck. The introducer catheter is fed over the guidewire and advanced to the cricothyroid membrane. D . An endotracheal tube is
advanced over the guidewire and introducer catheter until its tip is at the cricothyroid membrane. E. The hemostat has been removed. The
endotracheal tube is advanced as the guidewire and introducer catheter is removed.

Advance the guidewire through the catheter and into the oropharynx (Figures 23­2B & 23­3). The guidewire may exit the mouth or nose. The
preferred site of exit is the mouth, but the nose is acceptable. If it is not visualized, insert a laryngoscope and look for the guidewire. It is often in the
oropharynx or hypopharynx. Retrieve it with a Magill forceps. Continue to advance the guidewire through the mouth (or nose) until only 4 to 5 cm of the
wire is protruding from the patient's neck. Carefully remove the catheter while firmly holding the guidewire in place. Place a hemostat on
the guidewire where it enters the skin of the neck (Figure 23­2C). This will ensure that the tip does not pull through the skin and into the trachea.

Figure 23­3.

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wire is protruding from the patient's neck. Carefully remove the catheter while firmly holding the guidewire in place. Place a hemostat on by:
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the guidewire where it enters the skin of the neck (Figure 23­2C). This will ensure that the tip does not pull through the skin and into the trachea.

Figure 23­3.

The guidewire is inserted through the needle (or catheter depending on physician preference) until it exits the mouth.

If the kit is being used, select the introducer catheter contained in it. Pass the introducer catheter over the guidewire that is exiting the mouth (or nose).
Advance the catheter until resistance is met. This signifies that the tip of the introducer catheter is at the inside of the cricothyroid membrane (Figure
23­2C). Advance the well­lubricated endotracheal tube over the introducer and guidewire (Figure 23­2D). Continue to advance the endotracheal tube
until resistance is met. The tip of the endotracheal tube should be at the inside of the cricothyroid membrane (Figure 23­2D). While securely holding
the endotracheal tube at the patient's mouth, remove the hemostat from the guidewire. Pull on the proximal end of the guidewire until the distal tip is
through the skin and just into the endotracheal tube. Simultaneously withdraw the guidewire and introducer catheter while advancing the
endotracheal tube into the trachea (Figure 23­2E). Inflate the endotracheal tube cuff and confirm proper placement (i.e., auscultation, detection
of end­tidal CO2, fogging in the endotracheal tube, etc.).

A second method can also be used to insert the endotracheal tube. This follows the same technique described above to the point of the guidewire
exiting the mouth (or nose), being secured with a hemostat at the neck, and passing the introducer catheter over the guidewire. Remove the hemostat
from the guidewire. While securely holding the introducer catheter at the patient's mouth (or nose), remove the guidewire through
the mouth (or nose). Advance the introducer catheter an additional 2 to 3 cm into the trachea. Lubricate the endotracheal tube liberally. Place the
endotracheal tube over the introducer catheter. While holding the introducer catheter securely, advance the endotracheal tube into the patient's
trachea. Remove the introducer catheter. Inflate the endotracheal tube cuff and confirm proper placement (i.e., auscultation, detection of end­tidal
CO2, fogging in the endotracheal tube, etc.).

Alternative Techniques

This technique may be performed without a formal retrograde intubation kit as the introducer catheter is not required.7,12,13 This follows the same
technique described above to the point of the guidewire exiting the mouth (or nose) and being secured with a hemostat at the neck (Figure 23­2C).
Lubricate the endotracheal tube liberally. Insert the guidewire through the Murphy eye and into the endotracheal tube. This allows the distal tip of the
endotracheal tube to project approximately 1 cm distal to the site at which the guidewire enters the larynx. As an alternative, some physicians prefer to
load the guidewire through the tip of the endotracheal tube (Figure 23­4). Always hold the proximal end of the guidewire to maintain
control during the procedure. Advance the endotracheal tube over the guidewire until resistance is felt. The tip of the endotracheal tube should be
at the inside of the cricothyroid membrane. Hold the proximal end of the guidewire firmly. Release the hemostat over the neck. Pull the
guidewire through the skin and just into the endotracheal tube. Advance the endotracheal tube until it is at 20 to 21 cm at the teeth for an adult female
or 22 to 23 cm at the teeth for an adult male. Hold the endotracheal tube securely at the patient's lips. Withdraw the guidewire through the patient's
mouth. Inflate the endotracheal tube cuff and confirm proper placement (i.e., auscultation, detection of end­tidal CO2, fogging in the endotracheal
tube, etc.).

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guidewire through the skin and just into the endotracheal tube. Advance the endotracheal tube until it is at 20 to 21 cm at the teeth for an adult female
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or 22 to 23 cm at the teeth for an adult male. Hold the endotracheal tube securely at the patient's lips. Withdraw the guidewire through the patient's
mouth. Inflate the endotracheal tube cuff and confirm proper placement (i.e., auscultation, detection of end­tidal CO2, fogging in the endotracheal
tube, etc.).

Figure 23­4.

The endotracheal tube is advanced over the guidewire until the tip is against the cricothyroid membrane.

When the endotracheal tube is advanced over the guidewire until resistance is met, the tip should be situated against the inside of the cricothyroid
membrane. It is imperative to determine if the tip of the tube is in the trachea or caught on the epiglottis, arytenoid cartilage, pyriform recess, vallecula,
or vocal cords. If concern exists as to the position of the tip, withdraw the endotracheal tube 2 cm, rotate it 90°, and readvance it into the trachea. As an
alternative, a laryngoscope or fiberoptic broncho/nasopharyngoscope can be inserted to help visualize the placement of the endotracheal tube.

Another variation involves the use of the guidewire sheath as an introducer catheter.12,13 Shorten the sheath by 3 to 5 cm using sterile scissors. The
remainder of the technique is the same as described above. The only drawback to this technique is that the curvature of the sheath must be
straightened before use to allow easy threading over the guidewire.

In another description, a central venous catheter is used rather than a guidewire.6 It allows the physician to inject air through the catheter in
retrograde fashion to help locate the catheter in the mouth of the severely injured patient with significant intraoral blood or secretions. This technique
requires a relatively long central venous catheter. It does allow retrograde intubation without the use of a formal retrograde intubation kit.

Finally, another version uses a lighted stylet attached to the endotracheal tube.14 The lighted stylet acts as a guide to indicate the tube's location.
When the tip of the endotracheal tube enters the glottic opening, a bright, circumscribed glow is readily seen in the anterior neck, below the thyroid
prominence. This glow acts as an indicator of correct endotracheal tube placement.

When continuous oxygenation is required throughout the procedure, two possibilities exist.12 A T­adapter (1260, Deseret, Sandy, UT) can be
connected to the needle hub with its side arm for oxygen insufflation. Alternatively, a swivel adapter with a fiberoptic bronchoscopic cap (1/25/09,
Portex, Wilmington, MA) can be interposed between the endotracheal tube and the bag­valve­mask device or anesthesia breathing circuit.

Assessment
Auscultation of both lungs will confirm proper placement of the endotracheal tube and minimize the risk of intubation into the right mainstem
bronchus. End­tidal CO2 has also become part of the postintubation routine. After the procedure is completed, a chest radiograph will confirm the
placement of the endotracheal tube tip in relation to the clavicles and carina. Please refer to Chapter 12 for a more complete discussion of the methods
to confirm endotracheal intubation.
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The patient should receive standard wound care and dressing of the skin at the neck entrance site. Wound checks and infection monitoring should
Assessment
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Auscultation of both lungs will confirm proper placement of the endotracheal tube and minimize the risk of intubation into the right mainstem
bronchus. End­tidal CO2 has also become part of the postintubation routine. After the procedure is completed, a chest radiograph will confirm the
placement of the endotracheal tube tip in relation to the clavicles and carina. Please refer to Chapter 12 for a more complete discussion of the methods
to confirm endotracheal intubation.

Aftercare
The patient should receive standard wound care and dressing of the skin at the neck entrance site. Wound checks and infection monitoring should
continue as with any other surgical procedure. The risk of skin, tracheal, or pharyngeal infection is minimal if sterile technique was followed. If
infection develops, wound evaluation and treatment with appropriate antibiotics is warranted.

Complications
Complications of retrograde guidewire intubation include those of standard endotracheal intubation. Complications can occur when the needle
traverses the cricothyroid membrane.10 Hypoxia due to prolonged intubation time or incorrect endotracheal tube placement remains an important
complication. Drug reactions or side effects secondary to administered medications must always be considered.

Retrograde intubation is associated with additional complications due to use of the guidewire. One case report discusses a patient with a history of
retrograde intubation for coronary bypass surgery who experienced a foreign­body sensation and bloody sputum 2 years after the procedure.15 Upon
radiographic examination, the patient was found to have a 10 cm segment of guidewire fixed in the soft tissue of the puncture site and extending
cephalad 2 cm past the true vocal cords.

In one cadaveric study, numerous complications were noted during 40 cricothyroid punctures. Two punctures (5%) occurred below the cricothyroid
membrane. One was between the cricoid cartilage and the first tracheal ring. The other was between the first and second tracheal rings. Four cases
(10%) showed minor injuries to the thyroid or cricoid cartilage. Three cases (7.5%) showed injuries to the posterior wall of the larynx, epiglottis, or soft
palate. No posterior tracheal perforations were found in this study. The clinical importance of these injuries is unclear given the nature of this
postmortem study.

Three technical complications from retrograde guidewire intubation have been identified.10,12 Difficulties inserting the guidewire can be prevented
by first aspirating air into a saline­filled syringe to confirm the proper intratracheal needle tip position. Endotracheal intubation over a flexible
guidewire necessitates keeping the guidewire taut to minimize the risk of kinking. Unfortunately, this moves the guidewire anteriorly toward the
narrowest portion of the glottis and may prevent passage of the endotracheal tube, as the tip can become caught on the epiglottis or the vocal cords.
This problem is obviated by the use of the introducer catheter in the retrograde guidewire intubation kit. It lies in the posterior pharynx and glottis and
allows for easier passage of the endotracheal tube into the trachea. The tip of the endotracheal tube may flip out of the larynx when the introducer is
being removed, because the distance between the vocal cords and the point where the introducer enters and anchors the larynx averages only 1.0 to
1.3 cm in adults.

While complications may occur in association with retrograde intubation, the rate of complications is relatively low. In one study, 20 resident
physicians performed retrograde intubation twice each on 40 cadavers.10 In two cases (5%), the wire was fed caudad into the trachea due to improper
angling of the needle. The remaining intubations were performed without complications.

Summary
Retrograde guidewire intubation requires little operator experience or equipment. Multiple reports suggest that this technique is safe, relatively easy
to learn, and routinely successful. All physicians involved in the airway management of critically ill and injured patients should be aware of this
technique as a potential method to overcome the challenge of a difficult airway. Within the armamentarium of management techniques for the difficult
airway, retrograde guidewire intubation should be given due consideration in any situation in which orotracheal intubation is impossible or
contraindicated.

Numerous difficult airway management devices and adjuncts have been invented and marketed. Arguably, the various video­assisted laryngoscopy
devices have come to dominate the realm of alternative airway management techniques. The role of retrograde guidewire intubation as a difficult
airway management approach has further diminished as a consequence. However, retrograde guidewire intubation remains an easy­to­learn and
potentially lifesaving tool in the Emergency Physician's growing airway management armamentarium.

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References
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1. Van Stralen D, Rogers M, Perkin R, et al: Retrograde intubation training using a mannequin. Am J Emerg Med 1995;13:50–52.
 Access Provided by:
Numerous difficult airway management devices and adjuncts have been invented and marketed. Arguably, the various video­assisted laryngoscopy
devices have come to dominate the realm of alternative airway management techniques. The role of retrograde guidewire intubation as a difficult
airway management approach has further diminished as a consequence. However, retrograde guidewire intubation remains an easy­to­learn and
potentially lifesaving tool in the Emergency Physician's growing airway management armamentarium.

References

1. Van Stralen D, Rogers M, Perkin R, et al: Retrograde intubation training using a mannequin. Am J Emerg Med 1995;13:50–52.

2. Butler FS, Cirillo AA: Retrograde tracheal intubation. Anesth Analg 1960;39:333–338. [PubMed: 13806479]

3. Waters DJ: Guided blind endotracheal intubation. Anesthesia 1963;18:158–162. [PubMed: 13999148]

4. Powell WF, Ozdil T: A translaryngeal guide for tracheal intubation. Anesth Analg 1967;46:231–233. [PubMed: 6066979]

5. American Society of Anesthesiologists: Practice guidelines for management of the difficult airway. Anesthesiology 1993;78:597–602.

6. Barriot P, Riou B: Retrograde technique for tracheal intubation in trauma patients. Crit Care Med 1988;16:712–713. [PubMed: 3371049]

7. Van Stralen D, Perkin RM: Retrograde intubation difficulty in an 18­year­old muscular dystrophy patient. Am J Emerg Med 1995;13:100–101.

8. Harvey S, Fishman R, Edwards S: Retrograde intubation through a laryngeal mask airway. Anesthesiology 1996;85:1503–1504. [PubMed: 8968210]

9. Gotta AW, Sullivan CA: Anaesthesia of the upper airway using topical anaesthetic and superior laryngeal nerve block. Br J Anaesth 1981;53:1055–
1058. [PubMed: 7295450]

10. Stern Y, Spitzer T: Retrograde intubation of the trachea. J Laryngol Otol 1991;105:746–747. [PubMed: 1919344]

11. Borland LM, Swan DM, Lett S: Difficult pediatric endotracheal intubation: a new approach to the retrograde technique. Anesthesiology
1981;55:577–578. [PubMed: 7294412]

12. King HK, Wank LF, Khan AK, et al: Translaryngeal guided intubation for difficult intubation. Crit Care Med 1987;15:869–871. [PubMed: 3621963]

13. Lau HP, Yip KM, Liu CC: Rapid airway access by modified retrograde intubation. J Formos Med Assoc 1996;95(4):347–349. [PubMed: 8935308]

14. Hung OR, Al­Qatari M: Light­guided retrograde intubation. Can J Anaesth 1997;44(8):877–882. [PubMed: 9260016]

15. Contrucci RB, Gottlieb JS: A complication of retrograde intubation. Ear Nose Throat J 1990;69:776–778. [PubMed: 2276358]

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