The Radiological Measurement of Cervical Spine Extension during Bullard or Direct Laryngoscopy

Lee, Sangmin; Han, Tae Hyung; Kang, Yang Ja; Hwang, Won Gyoon; Lee, Jeong Jin; Shin, Baek Hyo

Abstract

Background: Conventional laryngoscopy with Macintosh blade requires a movement of the head, neck and cervical spine. The Bullard laryngoscope is an anatomically shaped, potentially eliminating the need for cervical spine extension. Bullard and Macintosh laryngoscopes were compared by measuring the degree of cervical spine extension by radiological measurement.
Methods
Eighteen patients requiring endotracheal intubation were studied. Anesthesia was induced in neutral head position followed by laryngoscopy. Each patients was intubated two times by Macintosh and Bullard laryngoscope in random order. Radiographic evaluation was performed to determine the degree of cervical spine extension on four occasions; before induction, during facial mask ventilation, and during Bullard and Macintosh laryngoscopy.
Results
The extension of cervical spine was significantly less following Bullard laryngoscopy than Macintosh laryngoscopy for best view (p<0.05).
Conclusions
The Bullard laryngoscope can be used with less cervical spine extension than Macintosh laryngoscope. It may be useful in patients in whom cervical spine movement is limited or undesirable.