Magnetic orotracheal intubation: a new technique.

We sought to determine the effectiveness of a magnet placed over the thyroid cartilage in the neck to guide an endotracheal tube into the trachea. Forty patients aged 18 to 60 yr with normal airway anatomy (ASA grade I) who required general anesthesia with an endotracheal tube and paralysis for their surgery were chosen and informed consents were obtained. The tip of the epiglottis was exposed with a No. 3 MacIntosh laryngoscope, and a magnet was held over the thyroid cartilage. A catheter with stylet was placed behind the epiglottis allowing the magnet to pull the stylet and catheter close to the glottic opening. The catheter was advanced into the trachea over the stylet and its position was confirmed by auscultating the lungs and by capnography. An extension tube was connected to the catheter, and the endotracheal tube was guided into the trachea over the catheter. The tracheas of 37 patients were intubated on the first attempt with the magnet. The tracheas of the remaining three patients could not be intubated on the first attempt but were successfully intubated without complications on the second attempt. An additional five patients with an anterior larynx whose tracheas could not be intubated with direct laryngoscopy also had tracheal intubation with a magnet. This magnet-guided technique can be used when it is difficult to expose a patient's larynx. It is noninvasive, simple, and can be used without any delay when expensive flexible fiberoptic endoscopes are not readily available. The procedure takes an average of 1 to 2 min.