Intubation with an Intermediate Airway in Place
Esophageal Obturator/Gastric Tube Airway in Place
The unconscious patient who requires ventilatory assistance may benefit from the temporary use of the esophageal obturator airway (EOA) or similar device. Although this may be an effective means of ventilation, it is at best a temporary measure. The patient experiencing upper airway hemorrhage with the EOA in place may have oropharyngeal blood insufflated into the trachea. Also, an endotracheal tube is the preferred airway, because with endotracheal intubation the airway is more secure and ventilation more convenient. Although the EOA may allow rapid airway support until cervical spine injury can be ruled out, it is recommended that the EOA not be left in place for more than 2 hours.
Replacement of the EOA with an orotracheal tube requires appropriate care. Removal of the esophageal cuff before placement of the endotracheal tube is fraught with danger. Spontaneous gastric regurgitation often occurs on EOA removal. The rescuer must therefore learn to perform endotracheal intubation around the EOA to protect the patient from aspiration.
The patient is hyperventilated through the EOA before intubation is attempted around it. The EOA mask is then removed, and the EOA tube is moved to the left side of the patient's mouth. Laryngoscopy and intubation are then performed in the usual fashion. If resistance to passage of the tracheal tube is met, the volume of the EOA balloon should be reduced, because the balloon may be producing distortion of the larynx. Next, the operator deflates the EOA balloon completely and slides it out of the patient's esophagus. If resistance is met, the operator must be sure that the esophageal cuff has been deflated completely.
Esophageal-Tracheal Combitube (ETC) in Place
Combitubes placed in the esophagus will generally require replacement with a tracheal tube. The inflated pharyngeal balloon prevents tracheal intubation around this airway. This proximal balloon must be deflated before attempting tracheal intubation. If intubation is still not possible, the ETC may need to be removed; the stomach should first be emptied via a gastric tube placed through the esophageal port of the airway. Suction is readied, the distal balloon is deflated, and the patient is quickly intubated. This maneuver poses an added risk over that associated with the esophageal obturator intermediate airway placement (i.e., EOA and EGTA) .
Laryngeal Mask Airway in Place
The trachea can often be intubated with the laryngeal mask airway (LMA) left in place.
Bullard Laryngoscope Use
A recent development for intubating the difficult airway is the Bullard laryngoscope, an anatomically shaped rigid fiberoptic laryngoscope that provides an indirect view of the larynx . It was design`ed to aid in intubating the difficult airway; and because no manipulation of the neck is necessary, it is especially well suited for the patient with potential cervical spine injury. Indeed, in the anesthetized patient, the Bullard laryngoscope has been found to cause less head extension and cervical spine extension than conventional laryngoscopes do. [36] The recent addition of an intubating stylet attached to the laryngoscope has resulted in increased ease and speed of intubation, and the technique appears to be effective regardless of the patient's head and neck anatomy. [37] Because alignment of the oropharyngeal and laryngeal axes is not required, the Bullard laryngoscope offers the advantage provided by a conventional fiberoptic scope but requires less training to gain proficiency in its use. [38]
Indications and Contraindications
The Bullard laryngoscope is indicated in patients with anticipated difficult airways who require definitive airway control. It can be used in awake as well as unresponsive patients. [39] The total inability to open the mouth is a contraindication to the use of this laryngoscope. However, because the Bullard laryngoscope follows the contour of the mouth and hypopharynx, only 2 cm of occlusal opening is necessary for the introduction of the scope plus endotracheal tube for intubation.
Procedure
The technique for introducing the Bullard laryngoscope blade is similar to that for direct laryngoscopy. The operator, who is at the head of the patient, opens the mouth with the left thumb while holding the head stable. As the scope blade is introduced into the oropharynx, the handle is rotated to follow the curve of the hypopharynx until the handle is fully vertical. The tip of the blade can be used to lift the epiglottis, but visualization of the larynx is usually possible without this maneuver. Only minimal force is exerted along the axis of the handle. Intubation of the larynx can be accomplished using a styletted endotracheal tube or an endotracheal tube with a directional tip (Endotrol; Mallinckrodt, Critical Care, Glens Falls, NY). The technique is generally successful when using the new Bullard intubating stylet. [37]
Awake intubation using the Bullard laryngoscope can be performed comfortably using topical anesthesia and light IV sedation. [39] Adult and pediatric Bullard laryngoscopes are available, and the scope has been used successfully in neonates. [38] The Bullard scope can also be used in conjunction with nasotracheal intubation and has the advantage of requiring only 6 mm of mouth opening through which to insert the blade. [40]
Complications
The major difficulty in using the Bullard laryngoscope is the inability to visualize the larynx because of blood, emesis, or secretions. Another reason for failure is the inability to place the blade tip under the epiglottis. [37]
Summary
The Bullard scope is useful in the difficult airway uncomplicated by blood and excessive secretions. In the all-too-common setting of blood and secretions, however, the inability to visualize the vocal cords significantly limits the utility of this device in emergency airway management.
Esophageal Obturator/Gastric Tube Airway in Place
The unconscious patient who requires ventilatory assistance may benefit from the temporary use of the esophageal obturator airway (EOA) or similar device. Although this may be an effective means of ventilation, it is at best a temporary measure. The patient experiencing upper airway hemorrhage with the EOA in place may have oropharyngeal blood insufflated into the trachea. Also, an endotracheal tube is the preferred airway, because with endotracheal intubation the airway is more secure and ventilation more convenient. Although the EOA may allow rapid airway support until cervical spine injury can be ruled out, it is recommended that the EOA not be left in place for more than 2 hours.
Replacement of the EOA with an orotracheal tube requires appropriate care. Removal of the esophageal cuff before placement of the endotracheal tube is fraught with danger. Spontaneous gastric regurgitation often occurs on EOA removal. The rescuer must therefore learn to perform endotracheal intubation around the EOA to protect the patient from aspiration.
The patient is hyperventilated through the EOA before intubation is attempted around it. The EOA mask is then removed, and the EOA tube is moved to the left side of the patient's mouth. Laryngoscopy and intubation are then performed in the usual fashion. If resistance to passage of the tracheal tube is met, the volume of the EOA balloon should be reduced, because the balloon may be producing distortion of the larynx. Next, the operator deflates the EOA balloon completely and slides it out of the patient's esophagus. If resistance is met, the operator must be sure that the esophageal cuff has been deflated completely.
Esophageal-Tracheal Combitube (ETC) in Place
Combitubes placed in the esophagus will generally require replacement with a tracheal tube. The inflated pharyngeal balloon prevents tracheal intubation around this airway. This proximal balloon must be deflated before attempting tracheal intubation. If intubation is still not possible, the ETC may need to be removed; the stomach should first be emptied via a gastric tube placed through the esophageal port of the airway. Suction is readied, the distal balloon is deflated, and the patient is quickly intubated. This maneuver poses an added risk over that associated with the esophageal obturator intermediate airway placement (i.e., EOA and EGTA) .
Laryngeal Mask Airway in Place
The trachea can often be intubated with the laryngeal mask airway (LMA) left in place.
Bullard Laryngoscope Use
A recent development for intubating the difficult airway is the Bullard laryngoscope, an anatomically shaped rigid fiberoptic laryngoscope that provides an indirect view of the larynx . It was design`ed to aid in intubating the difficult airway; and because no manipulation of the neck is necessary, it is especially well suited for the patient with potential cervical spine injury. Indeed, in the anesthetized patient, the Bullard laryngoscope has been found to cause less head extension and cervical spine extension than conventional laryngoscopes do. [36] The recent addition of an intubating stylet attached to the laryngoscope has resulted in increased ease and speed of intubation, and the technique appears to be effective regardless of the patient's head and neck anatomy. [37] Because alignment of the oropharyngeal and laryngeal axes is not required, the Bullard laryngoscope offers the advantage provided by a conventional fiberoptic scope but requires less training to gain proficiency in its use. [38]
Indications and Contraindications
The Bullard laryngoscope is indicated in patients with anticipated difficult airways who require definitive airway control. It can be used in awake as well as unresponsive patients. [39] The total inability to open the mouth is a contraindication to the use of this laryngoscope. However, because the Bullard laryngoscope follows the contour of the mouth and hypopharynx, only 2 cm of occlusal opening is necessary for the introduction of the scope plus endotracheal tube for intubation.
Procedure
The technique for introducing the Bullard laryngoscope blade is similar to that for direct laryngoscopy. The operator, who is at the head of the patient, opens the mouth with the left thumb while holding the head stable. As the scope blade is introduced into the oropharynx, the handle is rotated to follow the curve of the hypopharynx until the handle is fully vertical. The tip of the blade can be used to lift the epiglottis, but visualization of the larynx is usually possible without this maneuver. Only minimal force is exerted along the axis of the handle. Intubation of the larynx can be accomplished using a styletted endotracheal tube or an endotracheal tube with a directional tip (Endotrol; Mallinckrodt, Critical Care, Glens Falls, NY). The technique is generally successful when using the new Bullard intubating stylet. [37]
Awake intubation using the Bullard laryngoscope can be performed comfortably using topical anesthesia and light IV sedation. [39] Adult and pediatric Bullard laryngoscopes are available, and the scope has been used successfully in neonates. [38] The Bullard scope can also be used in conjunction with nasotracheal intubation and has the advantage of requiring only 6 mm of mouth opening through which to insert the blade. [40]
Complications
The major difficulty in using the Bullard laryngoscope is the inability to visualize the larynx because of blood, emesis, or secretions. Another reason for failure is the inability to place the blade tip under the epiglottis. [37]
Summary
The Bullard scope is useful in the difficult airway uncomplicated by blood and excessive secretions. In the all-too-common setting of blood and secretions, however, the inability to visualize the vocal cords significantly limits the utility of this device in emergency airway management.
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