Reduced hemodynamic responses to tracheal intubation by the Bonfils retromolar fiberscope: a randomized controlled study.

The Bonfils retromolar intubation fiberscope is a rigid endoscope designed to enable glottic visualization and facilitate intubation under endoscopic vision. Theoretically, avoiding direct-vision laryngoscopy and thus could produce less stimulation during intubation than the conventional direct laryngoscopic procedure. This prospective randomized study was designed to compare the effect of tracheal intubation with direct vision laryngoscopy (Macintosh blade) and the Bonfils retromolar intubation fiberscope on the hemodynamic responses in ASA I patients. Forty patients scheduled for elective surgery and requiring endotracheal intubation were randomly allocated to one of two groups according to the intubating tool under sevoflurane nitrous oxide Anaesthesia (n=20 each). The retromolar group received tracheal intubation with the Bonfils retromolar fiberscope, while the direct laryngoscopy group received tracheal intubation by the direct vision laryngoscope (Macintosh blade). Heart rate and arterial blood pressure (systolic BP, diastolic BP, mean ABP) were recorded before induction of Anaesthesia, 3 minutes after induction of Anaesthesia (before intubation) and 5 successive recordings at one-minute interval after intubation. All the systolic BP, diastolic Bp, mean ABP and heart rate values in the direct laryngoscopy group were significantly higher in the 5 successive minutes after intubation in comparison with the retromolar group (P = 0.00). This might be attributed to the gentle intubating technique, by the Bonfils retromolar fiberscope, which allows quick endotracheal intubation without manipulations of the base of the tongue or epiglottis.