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Correspondence  |   September 2010
Changing the Laryngoscope Blade and Its Effect on Laryngeal Visualization
Author Affiliations & Notes
  • Julien Amour, M.D., Ph.D.
    *
  • *Université Pierre et Marie Curie Univ Paris 06, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France.
Article Information
Correspondence
Correspondence   |   September 2010
Changing the Laryngoscope Blade and Its Effect on Laryngeal Visualization
Anesthesiology 9 2010, Vol.113, 750-751. doi:10.1097/ALN.0b013e3181eb0215
Anesthesiology 9 2010, Vol.113, 750-751. doi:10.1097/ALN.0b013e3181eb0215
In Reply:
We thank Dr. El-Orbany and colleagues for providing us the opportunity to clarify several points from our study.1 As we clearly explained, “After muscle fasciculations had been observed to ensure adequate muscle relaxation, tracheal intubation was performed using an endotracheal tube systematically associated with an internal stylet and cricoid pressure (Sellick's maneuver).”1,2 Therefore, in all patients during the intubation procedure (both first and second attempts), cricoid pressure was applied and maintained. However, a recent randomized study using a reusable metal blade demonstrated that the Sellick maneuver does not significantly increase the rate of failed intubations.3 In addition, as described in our study,1,2 the Cormack and Lehane score was obviously evaluated during cricoid pressure in both first and second attempts.
Because two recent studies demonstrated that peak force was not significantly different between single-use and reusable metal blades for tracheal intubation,4,5 and because force assessment markedly increases the complexity of the procedure and may influence the efficiency of an anesthesiologist in the specific case of patients undergoing general anesthesia requiring rapid sequence induction, the lifting force was not measured in our study. Moreover, Rassam et al.  5 observed that the grade of anesthetists (trainee or consultant) did not significantly affect the mean peak force applied during laryngoscopy. We confirmed these findings because intubation performances were similar between senior anesthesiologists, junior anesthesiologists, and nurse anesthetists recruited to participate in this multicenter randomized study. Finally, as reported in Hastings' study,6 lifting force is not significantly different among repeated laryngoscopies performed by the same anesthesiologist. In our study, first and second attempts were performed by the same operator. For all these reasons, we do not think that lifting force may have contributed to bias the results obtained in our study.
*Université Pierre et Marie Curie Univ Paris 06, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France.
References
Amour J, Le Manach YL, Borel M, Lenfant F, Nicolas-Robin A, Carillion A, Ripart J, Riou B, Langeron O: Comparison of single-use and reusable metal laryngoscope blades for orotracheal intubation during rapid sequence induction of anesthesia: A multicenter cluster randomized study. Anesthesiology 2010; 112:325–32Amour, J Le Manach, YL Borel, M Lenfant, F Nicolas-Robin, A Carillion, A Ripart, J Riou, B Langeron, O
Amour J, Marmion F, Birenbaum A, Nicolas-Robin A, Coriat P, Riou B, Langeron O: Comparison of plastic single-use and metal reusable laryngoscope blades for orotracheal intubation during rapid sequence induction of anesthesia. Anesthesiology 2006; 104:60–4Amour, J Marmion, F Birenbaum, A Nicolas-Robin, A Coriat, P Riou, B Langeron, O
Turgeon AF, Nicole PC, Trépanier CA, Marcoux S, Lessard MR: Cricoid pressure does not increase the rate of failed intubation by direct laryngoscopy in adults. Anesthesiology 2005; 102:315–9Turgeon, AF Nicole, PC Trépanier, CA Marcoux, S Lessard, MR
Evans A, Vaughan RS, Hall JE, Mecklenburgh J, Wilkes AR: A comparison of the forces exerted during laryngoscopy using disposable and non-disposable laryngoscope blades. Anaesthesia 2003; 58:869–73Evans, A Vaughan, RS Hall, JE Mecklenburgh, J Wilkes, AR
Rassam S, Wilkes AR, Hall JE, Mecklenburgh JS: A comparison of 20 laryngoscope blades using an intubating manikin: Visual analogue scores and forces exerted during laryngoscopy. Anaesthesia 2005; 60:384–94Rassam, S Wilkes, AR Hall, JE Mecklenburgh, JS
Hastings RH, Hon ED, Nghiem C, Wahrenbrock EA: Force and torque vary between laryngoscopists and laryngoscope blades. Anesth Analg 1996; 82:462–8Hastings, RH Hon, ED Nghiem, C Wahrenbrock, EA