LETTERS TO THE EDITOR: Letters & Announcements
To the Editor:
A 74-yr-old man with mandibular atrophy was scheduled for bilateral mandibular reconstruction. The surgeon requested a nasal intubation.
At the preoperative evaluation, review of the patient’s medical record indicated that his airway was difficult to intubate in the past. However, it seemed unclear from the records whether the difficulty was due to poor airway visualization during direct laryngoscopy or due to difficulties advancing the endotracheal tube secondary to a narrow glottic opening. The patient was unaware of this previous occurrence.
Upon examination, the patient had a Mallampati airway class I, a mouth opening of more than 5 cm, a thyromental distance of more than 5 cm, and an appropriate neck range of motion.
After airway topicalization with nebulized lidocaine 4%, the patient was taken to the operating room. Equipment for difficult intubation including a fiberoptic bronchoscope, LMA, intubating LMA, and cricothyroidotomy kit were readily available. After placement of the standard monitoring and preoxygenation, the patient was mask-induced using sevoflurane and 100% O2. Spontaneous ventilation was maintained. We determined that the patient could be easily mask ventilated. Once the depth of anesthesia was appropriate, direct laryngoscopy was attempted using a MacIntoch blade #4 resulting in a grade four McCormack visualization of the airway. Immediately, we proceeded to a nasal fiberoptic intubation attempt. However, the first attempt resulted in an esophageal intubation, and successive attempts were impaired by the presence of blood and secretions. An intubating LMA was placed, and we were able to advance into the trachea a 7.0 poly-vinyl-chloride endotracheal tube (ETT).
A conversion to a nasal intubation was now needed to proceed with the surgery. Initially, we attempted another nasal fiberoptic intubation. We planned to advance the scope into the trachea next to the existing orotracheal tube. However, this attempt was also unsuccessful due to secretions and blood. Maintaining the anesthetic depth with sevoflurane, a pediatric endotracheal tube exchanger (Cook airway exchange catheter, C-CAE-11.0–83, Bloomington, IN) was advanced into one of the nares. Once the tip was visualized in the oropharynx, it was brought out through the mouth. The adapter of the oral ETT was removed, and the cook catheter was advanced into the oral ETT. A nasal RAE was advanced over the proximal end of the cook airway exchange catheter (C-CAE) and into the nose. Then, the C-CAE’s 15-mm connector was attached to the anesthesia machine circuit, and oxygen was insufflated at 4 L per minute. This also allowed us to monitor the end tidal CO2. The orotracheal tube was then slowly withdrawn from the trachea into the mouth while keeping the Cook catheter in place, which was similar to the Seldinger technique.
As it was withdrawn, the oral tube was cut longitudinally with a 10 blade and removed in a “tear away” manner from the C-CAE. Finally, the nasal RAE was advanced into the trachea over the C-CAE, and the catheter was then removed. The presence of bilateral breath sounds and end tidal CO2 confirmed appropriate tube positioning. No episodes of desaturation occurred. The surgery was started, and the patient’s trachea was extubated without complication upon completion of the operation.
Reports of nasal to orotracheal intubation exist in the literature (1–3). However, the authors are aware of only one report of oral to nasal endotracheal tube exchange. In that report, the use of a endotracheal tube exchanger (Patil Two-part Intubation Catheter Cook, Bloomington, IN) which consists of two parts was described. This exchanger has a tracheal part and an extension part, which can connect to each other (4). The lumen is hollow, allowing for jet ventilation. The technique described was similar to ours. However, in their case, the oral tube was removed while disconnecting the two-part catheter. Because such a catheter is not available in our department, we cut the tube longitudinally and removed it in the tear away manner described above.
Management of difficult airway situations represents one of the most difficult and stressful challenges for the anesthesiologist. In our case, we were able to secure the airway, but to continue with the planned surgery, the tube needed to be changed from oral to nasal. In this circumstance, an appropriate plan of action must be present in case the initial technique fails in securing the airway. The technique we describe permits changing the oral tube to a nasal tube safely because there is no point where the airway or the ability to ventilate the patient is compromised because oxygen insufflation or jet ventilation is possible with the C-CAE.
Hasmig Salibian, MD
Sanjay Jain, MD
David Gabriel, MD
Ruben J. Azocar, MD
1. Cooper R. Conversion of a nasal to an orotracheal intubation using an endotracheal tube exchanger. Anesthesiology 1997; 87: 717–8.
2. Gabriel DM, Azocar RJ. A novel technique for conversion of nasotracheal tube to orotracheal. Anesthesiology 2000; 93: 911.
3. Tapnio RU, Viegas OJ. An alternative method for conversion of a nasal to an orotracheal intubation. Anesthesiology 1998; 88: 1683–4.
4. Nakata Y, Niimi Y. Oral-to-nasal endotracheal tube exchange in patients with bleeding esophageal varices. Anesthesiology 1995; 83: 1380–1.