Anesth Analg 2007; 105:1753-1754
© 2007 International Anesthesia Research Society
doi: 10.1213/01.ane.0000286322.04940.a5
GENERAL ARTICLES
The Use of a Laryngeal Mask Airway After a Prolonged Suspension Laryngoscopy to Preserve a Vocal Cord Fat Graft
Daniel C. H. Kidani, MD, and
Nitin K. Shah, MD
From the Department of Anesthesiology, University of California Irvine Medical Center, California.
Address correspondence and reprint requests to Daniel C. H. Kidani, MD, UC Irvine Medical Center, 101 The City Drive South, Bldg. 53 Rm. 228 Rt. 81A, Orange, CA 92868. Address e-mail to dkidani{at}yahoo.com.
 |
Abstract
|
|---|
A 62-yr-old man presented for a microdirect laryngoscopy and vocal cord fat grafting under jet ventilation. After a prolonged laryngoscopy, the patient developed hypercapnea and upper airway obstruction secondary to traumatic epiglottitis. The placement of a laryngeal mask airway provided ventilation and allowed for direct visualization of the patient’s inflamed epiglottis without disruption of the patient’s fat graft. Because of its placement above the cords and its effectiveness in providing adequate ventilation, we propose intermittent laryngeal mask airway ventilation as a bridge, in lieu of endotracheal intubation, in microdirect laryngoscopy cases in which ventilation during emergence may be difficult and the insertion of an endotracheal tube would disrupt the surgical procedure.
|
Introduction
|
|---|
Anesthesia and airway management during suspension microlaryngoscopy is complicated, because both the surgeon and the anesthesiologist must share the airway. Before jet ventilation, the most common anesthetic technique was to provide general anesthesia through a small endotracheal tube (ETT), to allow both an adequate surgical field of view and adequate ventilation. With the advent of the jet ventilator, nasotracheal and transtracheal microcatheters, as well as direct ventilation through the laryngoscope, have been used. Jet ventilation minimizes, if not eliminates, catheters or tubes in the surgical field. However, there is the potential for hypoventilation. Intermittent insertion of an ETT has been used to supplement ventilation, but may disrupt the surgical procedure. We present a case demonstrating the use of laryngeal mask airway (LMA) ventilation after a suspension laryngoscopy case, in lieu of endotracheal intubation, to protect a vocal cord fat graft.
|
CASE REPORT
|
|---|
A 62-yr-old man (5 ft 11 in.) weighing 85 kg, with a medical history of hypertension and a mitral valve replacement 7 mo before surgery, presented for a microdirect laryngoscopy and vocal cord fat grafting for a paralyzed left true vocal cord secondary to a prolonged intubation after his mitral valve replacement. His physical examination was unremarkable. His room air oxygen saturation was 98%. He was premedicated with midazolam and brought to the operating room where standard monitors were placed and oxygen was administered. He underwent a smooth IV induction with propofol and cisatracurium and was easy to mask ventilate. At this time, the surgeons took control of the airway and placed a direct suspension laryngoscope through which jet ventilation was performed. Maintenance of anesthesia was provided by a propofol infusion at 100–250 µg · kg–1 · min–1, fentanyl boluses (total of 100 µg), and intermittent boluses of cisatracurium, monitored with a twitch monitor, keeping the train-of-four response between 0 and 2 of 4. He was hemodynamically stable and his oxygen saturation was maintained throughout the procedure. The surgery lasted approximately 2.5 h because of difficulty in placing the fat graft. His oxygenation was adequate with oxygen saturations between 91% and 98% with intermittent jets of 100% oxygen. Peak pressures were maintained below 50 psi, and the laryngoscope was kept above the vocal cords and in-line with the trachea. The patient remained hemodynamically stable with systolic blood pressures between 130 and 150 mm Hg and a heart rate between 80 and 100 bpm. At the end of surgery, the laryngoscope was removed, and he was mask-ventilated. The propofol infusion was stopped and the neuromuscular blockade was fully reversed.
The patient quickly developed stridor with spontaneous ventilation, which was attributed to upper airway obstruction. His oxygen saturation transiently decreased to 80%. Given his history of unilateral vocal cord paralysis, vocal cord spasm was unlikely. A #5 disposable LMA was easily placed without further sedation and his lungs were ventilated with moderate difficulty. His oxygen saturation rapidly returned to 97% with LMA ventilation. His initial end-tidal carbon dioxide (ETco2) after LMA placement was 65 mm Hg. A flexible bronchoscope was passed through the LMA and an inflamed epiglottis was identified, likely secondary from laryngoscope trauma (Fig. 1). Dexamethasone 10 mg IV was given.
View larger version (48K):
[in this window]
[in a new window]
|
Figure 1. Inflamed epiglottis after prolonged suspension laryngoscopy viewed through a fiberoptic bronchoscope.
|
|
During the next 20 min, signs of obstruction, airway rhonchi, and accessory muscle use decreased. The patient’s ETco2 decreased to 42 mm Hg and he emerged from anesthesia. The LMA was removed and the patient remained stable breathing spontaneously with supplemental oxygen via facemask. After an overnight hospitalization, a repeat visualization of his epiglottis via a flexible bronchoscope showed resolution of epiglottic inflammation and no disruption of the surgical fat grafting. He was discharged home.
|
DISCUSSION
|
|---|
Airway management during microlaryngoscopy is problematic, because the anesthesiologist and surgeon must share the airway (1–3). Before the use of the jet ventilator, many ventilation and anesthetic techniques had been used for laryngeal inspection and surgery: use of a chest respirator, apneic oxygenation techniques, topical anesthesia, translaryngeal topical anesthesia, neuroleptoanalgesia, and general endotracheal anesthesia (1). The most popular of these was the general anesthesia with ventilation via endotracheal intubation. Unfortunately, the presence of an ETT obscured the surgical field of view and the use of small diameter ETTs limited ventilation (1).
The advent of the jet ventilator made it possible to minimize or eliminate ETTs from the operative field (2,4). Jet ventilation uses high-pressure jets of oxygen to inflate the lungs. Air is delivered from the jet itself as well as entrained air from the Venturi effect (2). Adequacy of ventilation relies on correct laryngoscope placement just above the cords, in line with the axis of the trachea, as well as adequate expiratory time to allow for passive exhalation of CO2 (2). Rajagopalan et al. (5) demonstrated adequate oxygenation and ventilation after 90 min of jet ventilation.
Hypoventilation, pneumomediastinun, pneumothorax, and severe abdominal distension (1–5) have been cited as complications of jet ventilation. The latter three are directly related to the high-pressure jet itself. In a recent review article by Jaquet et al. (6), it was noted that transtracheal jet ventilation via a microcatheter was related to a significantly higher complication rate than transglottal microcatheter jet ventilation. All severe complications were related to barotraumas resulting from airway outflow obstruction, mostly involving laryngospasm.
Obese patients and patients with poor lung compliance may be difficult to ventilate as well as those with short stiff necks as placement of the laryngoscope is compromised (3). Our patient, however, had a body mass index of 26, and no smoking history or lung pathology. He did, however, have a muscular chest wall, which may have decreased lung compliance.
This case presented two main airway issues: hypoventilation from jet ventilation and traumatic epiglottitis from prolonged laryngoscopy. The patient was fully paralyzed. Although the laryngoscope was in optimal position, ventilation with good chest rise was difficult. Ventilation with an ETT was a poor option because of the high likelihood of disrupting the grafted fat pad. The increased ETco2 at the end of the case, 65 mm Hg, was well tolerated and resolved spontaneously with awakening.
|
CONCLUSION
|
|---|
The LMA placed at the end of this case ensured adequate ventilation without risk of disrupting the fat graft, and facilitated emergence from anesthesia and resolution of the hypercapnea. It also facilitated diagnosis of the inflamed epiglottis. Because of its placement above the cords and effectiveness in facilitating adequate ventilation, we propose using LMA ventilation as a bridge, in lieu of endotracheal intubation, in microdirect laryngoscopy cases where ventilation during emergence may be difficult and the insertion of an ETT would disrupt the surgical procedure.
|
ACKNOWLEDGMENTS
|
|---|
The authors thank Roger L. Crumley, MD, Chairman and Clinical Professor of ENT Surgery, and John F. McGuire, MD, Resident in ENT Surgery.
|
Footnotes
|
|---|
Accepted for publication August 3, 2007.
|
REFERENCES
|
|---|
- Norton ML, Strong MS, Snow JC, Vaughan CW, Kripke BJ. Endotracheal intubation and venturi jet ventilation for laser microsurgery of the larynx. Ann Otol Rhinol Laryngol 1976; 85:656–63[ISI][Medline]
- Spoerel WE, Greenway RE. Technique of ventilation during endolaryngeal surgery under general anesthesia. Can Anaesth Soc J 1973;20:369–77[ISI][Medline]
- O’Sullivan TJ, Healy G. Complications of venturi jet ventilation during microlaryngeal surgery. Arch Otolaryngol 1985;111:127–31[Abstract]
- Winerman I, Ezra S, Man A, Segal S. Limitations of jet ventilation through the laryngoscope. Can J Anaesth 1982;29:117–20[Abstract/Free Full Text]
- Rajagopalan R, Smith F, Ramachandran PR. Anesthesia for microlaryngoscopy and definitive surgery. Can Anaesth Soc J 1972;19:83–6[ISI][Medline]
- Jaquet Y, Monnier P, Van Melle G, Ravussin P, Spahn D, Chollet-Rivier, M. Complications of different ventilation strategies in endoscopic laryngeal surgery: a 10 year review. Anesthesiology 2006;104:52–9[ISI][Medline]
Top
Abstract
Introduction
