COMPARISON OF THE BULLARD AND MACINTOSH LARYNGOSCOPES FOR ENDOTRACHEAL INTUBATION OF PATIENTS WITH A POTENTIAL CERVICAL-SPINE INJURY

Background: In the emergency trauma situation, in-line stabilization ( ILS) of the cervical spine is used to reduce head and neck extension d uring laryngoscopy. The Bullard laryngoscope may result in less cervic al spine movement than the Macintosh laryngoscope. The aim of this stu dy was to compare cervical spine extension (measured radiographically) and time to intubation with the Bullard and Macintosh laryngoscopes d uring a simulated emergency with cervical spine precautions taken. Met hods: Twenty-nine patients requiring general anesthesia and endotrache al intubation were studied. Patients were placed on a rigid board and anesthesia was induced. Laryngoscopy was performed on four occasions: with the Bullard and Macintosh laryngoscopes both with and without man ual ILS. Cricoid pressure was applied with ILS. To determine cervical spine extension, radiographs were exposed before and during laryngosco py. Times to intubation and grade view of the larynx were also compare d. Results: Cervical spine extension (occiput-C5) was greatest with th e Macintosh laryngoscope (25.9 degrees +/- 2.8 degrees). Extension was reduced when using the Macintosh laryngoscope with ILS (12.9 +/- 2.1 degrees) and the Bullard laryngoscope without stabilization (12.6 +/- 1.8 degrees; P < 0.05). Times to intubation were similar for the Macin tosh laryngoscope with ILS (20.3 +/- 12.8 s) and for the Bullard witho ut ILS (25.6 +/- 10.4 s). Manual ILS with the Bullard laryngoscope res ults in further reduction in cervical spine extension (5.6 +/- 1.5 deg rees) but prolongs time to intubation (40.3 +/- 19.5 s; p < 0.05). Con clusions: Cervical spine extension and time to intubation are similar for the Macintosh laryngoscope with ILS and the Bullard laryngoscope w ithout ILS. However, time to intubation is significantly prolonged whe n the Bullard laryngoscope is used in a simulated emergency with cervi cal spine precautions taken. This suggests that the Bullard laryngosco pe may be a useful adjunct to intubation of patients with potential ce rvical spine injury when time to intubation is not critical.