The study was conducted to evaluate the usefulness of an esophageal detector device (EDD) to correctly differentiate between esophageal and tracheal intubation. The study was conducted in the emergency department using 10 recently decreased cadavers (nine males, one female, age range 50-72 years). An 8-mm internal diameter endotracheal tube was placed orally into the trachea, and a second 8-mm ID tube was placed orally into the esophagus. Both tubes extended the same distance from the mouth, and the cuffs were not inflated. After placement of the tubes, the EDD was used by advanced life support providers (physicians, nurses, paramedics, and respiratory therapists) to determine if each tube was in the trachea or the esophagus. The persons who assessed the tube placement were not present when the tubes were placed into the cadavers. Multiple evaluators were allowed for each cadaver, but each evaluator only participated one time for each cadaver. The bulb of the EDD was squeezed by the evaluator, who then attached it to the endotracheal tube and rated the bulb inflation as immediate inflation, delayed inflation, or no inflation. Prior to participation in the study, evaluators were instructed in the use of the EDD. There were a total of 45 trials performed on the cadavers (median, four evaluations/cadaver, range, one-eight). For the tracheal tube, the EDD inflated immediately in all cases; it was thus 100% correct in identification of tracheal intubation. For the esophageal tube, the EDD did not inflate in 44 cases, and in one case it filled with vomitus; it thus correctly identified esophageal intubation in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)