Correct positioning of an endotracheal tube using a flexible lighted stylet

Endotracheal intubation is not without complications, among the most serious of these being misplacement of the endotracheal (ET) tube. Unrecognized esophageal placement is a lethal complication, but even when placed in the trachea, ET tubes can be displaced distally and enter a mainstem bronchus. Correct positioning of an ET tube is usually defined as the placement of the tube within the trachea approximately 5 cm above the carina. Chest x-ray is the most common and a reliable method of demonstrating correct positioning, particularly in ICU patients. Using transillumination by means of a flexible stylet (lightwand), we investigated whether transillumination could position an ET tube consistently within 5 +/- 2 cm of the carina. Ten human cadavers of varied weight and body habitus were intubated under direct vision and 10 ml of a radiopaque dye was injected down the tube as a marker for the carina. A premeasured flexible lighted stylet was then inserted into the inplace tube so that the bulb was positioned at the tube's distal opening. The brightest transilluminated glow produced by the bulb was then positioned at the sternal notch. A chest x-ray was taken and the distance of the tube tip from the carina was calculated. In each case the tube tip could be placed consistently at a level 5 +/- 1 cm from the carina by observing the maximal transilluminated glow at the sternal notch. We conclude that transillumination of the neck using a flexible lighted stylet can accurately and consistently position an ET tube at an appropriate distance above the carina.(ABSTRACT TRUNCATED AT 250 WORDS)