RESUMEN
BACKGROUND: Endotracheal intubation with direct laryngoscope requires movement of the head, neck, and cervical spine. Spine movement may be limited for anatomical reasons or because of cervical spine injury. The lightwand requires less neck flexion and head extension than the conventional laryngoscope. The purpose of this study was to compare the extension of cervical spine obtained with lightwand and Macintosh laryngoscope. METHODS: Twenty patients requiring general anesthesia with endotracheal intubation were studied. Patients were placed on the operating table and anesthesia was induced. Intubation were performed on two occasions: with lightwands and Macintosh #3 laryngoscopes. Cricoid pressure was not applied. To determine cervical spine extension, five radiographs were taken in each patient (before induction, during mask ventilation, during intubation with lightwand, during laryngoscopy with the Macintosh blade: in the best glottic view or during intubation). RESULTS: Of 20 cases, we excluded 2 cases due to the technical error. Significant reduction of radiographic cervical spine extension were found in the lightwand compared to Macintosh blade at all cervical level. Mean atlantooccipital extension angles were 6.2o and 11.7o for the lightwand and Macintosh, respectively. There were no significant differences between mask ventilation and intubation with lightwand. CONCLUSIONS: Lightwand may be better than the conventional intubation in patients whose cervical spine movement is limited or undesirable, especially in the patients in whom awake intubation is not available.