Mallampati SR. Clinical sign to predict difficult tracheal intubation (hypothesis). Can Anaesth Soc J. 1983 May. 30(3 Pt 1):316-7. [Medline].
Mallampati SR, Gatt SP, Gugino LD, Desai SP, Waraksa B, Freiberger D, et al. A clinical sign to predict difficult tracheal intubation: a prospective study. Can Anaesth Soc J. 1985 Jul. 32(4):429-34. [Medline].
Apfelbaum JL, Hagberg CA, Caplan RA, Blitt CD, Connis RT, Nickinovich DG, et al. Practice guidelines for management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Anesthesiology. 2013 Feb. 118(2):251-70. [Medline].
Lee A, Fan LT, Gin T, Karmakar MK, Ngan Kee WD. A systematic review (meta-analysis) of the accuracy of the Mallampati tests to predict the difficult airway. Anesth Analg. 2006 Jun. 102(6):1867-78. [Medline].
Ezri T, Warters RD, Szmuk P, Saad-Eddin H, Geva D, Katz J, et al. The incidence of class "zero" airway and the impact of Mallampati score, age, sex, and body mass index on prediction of laryngoscopy grade. Anesth Analg. 2001 Oct. 93(4):1073-5, table of contents. [Medline].
Fiberoptic bronchoscope may be a good intubating tool in anesthetized patients with predicted difficult intubation. We conducted this prospective randomized study to compare intubation using FOB and direct laryngoscopy (DL) after induction of general anesthesia.
One hundred adult patients (50 patients in DL group, and 50 patients in the FOB group) with at least one difficult intubation criteria were enrolled in the study. Both FOB and DL were attempted after induction of anesthesia and verification of mask ventilation. Incidence of failed intubation (more than two attempts), successful intubation, and total induction times were recorded. Adverse events during intubation process were documented. Postoperatively, patients fulfilled a questionnaire to assess sequale of intubation.
The overall success rate for tracheal intubation was higher in the FOB (100% Vs 86%; p < 0.05). Successful primary and secondary intubation attempts were higher in the FOB group (94% Vs 64%; p < 0.05 and 100% Vs 61%; p < 0.05, respectively). All patients who failed laryngoscopic intubation were successfully intubated using the fiberoscope. Induction and successful intubation times were longer in the laryngoscopy group (128 + 93.7 s Vs 79.9 + 27.2 s p < 0.05 and 67.5 + 88.6 s Vs 19.2 + 27 s p < 0.05, respectively). Adverse effects including tissue trauma and dental injury were greater in the DL group. Postoperative patient's dissatisfaction, sore throat, and hoarseness were statistically higher in the DL group.
We concluded that, FOB is an effective and safe intubating tool in anesthetized patients with anticipated difficult intubation.