| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Correspondence |
Dr. Peset Universitary Hospital, Valencia, Spain E-mail: jose.higueras{at}uv.es
To the Editor:
Fibreoptic tracheal intubation is useful for difficult airways. Two major difficulties with this technique are: insertion of the fibrescope into the trachea and then, advancing the endotracheal tube (ETT) over the fibrescope.1 This second difficulty is attributed to catching of the ETT on supraglottic structures.2 The Parker Flex-TipTM tube (PFT; Parker Medical, Englewood, CO, USA) overcame this difficulty in a case of lingual tonsil hypertrophy (LTH).
A 56-yr-old previously healthy woman was scheduled for hemithyrodectomy. There was no indication of a difficult airway. After induction of anesthesia, laryngoscopy revealed a grade 4 Cormack Lehane view. The intubation was impossible. We decided to waken the patient and try nasotracheal fibreoptic intubation. A 6.5-mm internal diameter (ID) standard tube (Hi-ContourTM, Mallinckrodt Medical, Ireland) was inserted over the fibrescope (Pentax, 3.5-mm outer diameter). The fibrescope was successfully directed into the trachea, but the ETT would not advance, so the procedure was abandoned. A few days later, the patient was monitored and prepared following our standard nasotracheal fibreoptic intubation protocol. We chose a 6.5-mm ID PFT. As the fibrescope advanced a LTH was discovered, narrowing between the epiglottis and the posterior pharyngeal wall. Once the carina was visible, the PFT was easily displaced over the fibrescope into the trachea.
Supraepiglottic masses, like LTH, are recognized risk factors for unanticipated failed tracheal intubation.3 LTH may also cause massive bleeding following instrumentation of supraglottis4 and in the worst possible case it may become a "cannot-intubate-cannot-ventilate" situation. In our case, LTH could be the cause of a difficult advancement of the tube.
The major reason for difficulty in advancing an ETT over a fibrescope is impingement of the tube’s tip in different parts of the supraglottis;1 this can be markedly reduced by using a flexible tube. Ovassapian et al.3 studied 33 patients with unanticipated failed intubation, via direct laryngoscopy. LTH was discovered in all patients.
Kristensen reduced two-thirds the rate of resistance to passage of the tube into the trachea by comparing the PFT with the standard tube (PortexTM) during fibreoptic orotracheal intubation.5 Utilization of thinner fibrescopes, or greater ID tubes is possible because the PFT mainly reduces the gap between the scope and the tube (Figure
). Reduction of the gap, joined to the use of flexible tubes are the main recommendations given by Asai et al.1
|
References
1 Asai T, Shingu K. Difficulty in advancing a tracheal tube over a fibreoptic bronchoscope: incidence, causes and solutions. Br J Anaesth 2004; 92: 870–81.
2 Schwartz D, Johnson C, Roberts J. A maneuver to facilitate flexible fiberoptic intubation. Anesthesiology 1989; 71: 470–1.[Medline]
3 Ovassapian A, Glassenberg R, Randel GI, Klock A, Mesnick PS, Klafta JM. The unexpected difficult airway and lingual tonsil hyperplasia: a case series and a review of the literature. Anesthesiology 2002; 97: 124–32.[Medline]
4 Tokumine J, Sugahara K, Ura M, Takara I, Oshiro M, Owa T. Lingual tonsil hypertrophy with difficult airway and uncontrollable bleeding. Anaesthesia 2003; 58: 390–1.[Medline]
5 Kristensen MS. The Parker Flex-Tip tube versus a standard tube for fiberoptic orotracheal intubation: a randomized double-blind study. Anesthesiology 2003; 98: 354–8.[Medline]
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
