Letters to the Editor: Letters & Announcements
To the Editor:
A 34-year-old man (182 cm tall, 128 kg weight) was scheduled for excision of a vocal cord tumor. The patient had a Mallampati Class 2 airway with an interincisor distance of 5 cm and adequate neck extension. Following induction of anesthesia with fentanyl, propofol, and succinylcholine, we performed laryngoscopy using a Macintosh blade and obtained a Cormack–Lehane Grade 3 view of the vocal cords. A small tracheal tube for laser surgery (internal diameter of 5.5 mm) was placed.
Postoperatively, the patient's ventilation deteriorated with an increase in mean inspiratory pressure from 15 to 35 cm H2O and diffuse wheezing. We administered salbutamol and methylprednisolone and transferred the patient to the intensive care unit. There, the endotracheal tube was exchanged for a larger one under direct visual control with the GlideScope video laryngoscope (Saturn Biomedical System, Burnaby, British Columbia, Canada). A few minutes later, we heard an air leak, and we noticed that the endotracheal tube pilot balloon was deflated. We exchanged the endotracheal tube by means of an airway exchange catheter, again using the Glidescope to guide us. On both occasions, we obtained a Cormack– Lehane Grade 1 view of the vocal cords.
Replacing an endotracheal tube in a patient with compromised oxygenation is potentially dangerous. However, because the endotracheal tube exchange failed (1) and serious complications from using an airway exchange catheter (2) have been reported, we recommend the GlideScope for endotracheal tube exchanges. It has several features that are useful in managing difficult airways. First, an embedded antifogging mechanism prevents clouding of the image on the video display. Second, the 60° angle blade provides a minimally distorted view of the supraglottic anatomy. Third, the GlideScope's design is similar to that of a conventional laryngoscope, making it easy for conventional laryngoscope users to use. Finally, some studies have shown that the GlideScope improves the laryngoscopic view (3–5). In our patient, the GlideScope view was two Cormack–Lehane grades higher than that obtained with a Macintosh blade and a conventional laryngoscope. The GlideScope is useful for airway management, including endotracheal tube exchanges in the intensive care unit.
David Peral, MD
Elena Porcar, MD
Jorge Bellver, MD
José Higueras, MD
Xavier Onrubia, MD
Manuel Barberá, PhD
Hospital Doctor Peset
1. Eisenach JH, Barnes RD. Potential disaster in airway management: a misguided airway exchange catheter via a hole bitten into a Univent endotracheal tube. Anesthesiology 2002;96:1266–8.
2. Mort TC, Meisterling EM, Waberski WM. Exchanging a tracheal tube in the ICU patient: a comparison of two exchangers with direct laryngoscopy [abstract]. Anesthesiology 1997;89:240A.
3. Rai MR, Dering A, Verghese C. The Glidescope® system: a clinical assessment of performance. Anaesthesia 2005;60:60–4.
4. Sun DA, Warriner CB, Parsons DG, et al. The Glidescope® Video Laryngoscope: randomized clinical trial in 200 patients. Br J Anaesth 2005;94:381–4.
5. Cooper RM, Pacey JA, Bishop MJ, McCluskey SA. Early clinical experience with a new video laryngoscope (Glidescope®) in 728 patients. Can J Anaesth 2005;52:191–8.