Luck, Pluck, and the Making of the Macintosh Laryngoscope

Background In the emergency trauma situation, in-line stabilization (ILS) of the cervical spine is used to reduce head and neck extension during laryngoscopy. The Bullard laryngoscope may result in less cervical spine movement than the Macintosh laryngoscope. The aim of this study was to compare cervical spine extension (measured radiographically) and time to intubation with the Bullard and Macintosh laryngoscopes during a simulated emergency with cervical spine precautions taken. Methods Twenty-nine patients requiring general anesthesia and endotracheal 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 manual ILS. Cricoid pressure was applied with ILS. To determine cervical spine extension, radiographs were exposed before and during laryngoscopy. Times to intubation and grade view of the larynx were also compared. Results Cervical spine extension (occiput-C5) was greatest with the 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 Macintosh laryngoscope with ILS (20.3 +/- 12.8 s) and for the Bullard without ILS (25.6 +/- 10.4 s). Manual ILS with the Bullard laryngoscope results in further reduction in cervical spine extension (5.6 +/- 1.5 degrees) but prolongs time to intubation (40.3 +/- 19.5 s; P < 0.05). Conclusions Cervical spine extension and time to intubation are similar for the Macintosh laryngoscope with ILS and the Bullard laryngoscope without ILS. However, time to intubation is significantly prolonged when the Bullard laryngoscope is used in a simulated emergency with cervical spine precautions taken. This suggests that the Bullard laryngoscope may be a useful adjunct to intubation of patients with potential cervical spine injury when time to intubation is not critical.

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McGrath Video Laryngoscope May Take a Longer Intubation Time Than Macintosh Laryngoscope

Journal of Anesthesiology ◽

10.1155/2015/901903 ◽

2015 ◽

Vol 2015 ◽

pp. 1-4

Author(s):

Prerana N. Shah ◽

Kaveri Das

Keyword(s):

Randomized Study ◽

Macintosh Laryngoscope ◽

Total Duration ◽

Video Laryngoscope ◽

Intubation Time ◽

Laryngoscopic View ◽

Lehane Grade ◽

Secondary Endpoints ◽

Grade Ii ◽

Grade Iii

Background. Video laryngoscopes provide better view and can improve ease of intubation compared with standard laryngoscopes. Methods. A prospective randomized study was done on 60 patients, 18 to 65 years old, comparing McGrath video laryngoscope and Macintosh laryngoscope. The aim was to compare the ease, efficacy, and usability of them during routine airway management. The primary endpoint was duration of intubation and the secondary endpoints were Cormack and Lehane grade of laryngoscopic view, number of intubation attempts, and incidence of complications. Results. There was an increase in total duration of intubation with McGrath video laryngoscope with 42.9 ± 19.5 seconds compared to Macintosh laryngoscope with 17.9 ± 4.6 seconds. In Macintosh group, 73.3% had grade I, 20% had grade II, and 6.7% had grade III Cormack Lehane view, while in McGrath group, 83.3% had grade I, 13.3% had grade II, and 3.3% had grade III. In McGrath group, 6 patients (20%) required more than 120 seconds to get intubated and only 73.3% were intubated in 1 attempt, while patients in Macintosh group had 100% successful intubation in 1 attempt. Pharyngeal trauma was seen with McGrath videolaryngoscopy. Conclusion. Duration of laryngoscopy, intubation, and total duration of intubation were significantly higher in McGrath group than in Macintosh group. McGrath group required a higher number of intubation attempts.

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