Improved esophageal patency when inserting the ProSeal™ laryngeal mask airway with an Eschmann™ tracheal tube introducer

Abstract

We hypothesized that a more accurate alignment of the tip of the drain tube with the upper esophageal opening would be achieved in adult patients, as confirmed by fibreoptic bronchoscopy, by placing the ProSeal laryngeal mask airway (PLMA) by means of guiding it over an Eschmann tracheal tube introducer, commonly know as a gum elastic bougie (GEB), that was previously inserted into the esophagus, rather than by placing the PLMA with a curved metal introducer (IT). Seventy-five adult elective surgery patients, whose airway management involved a PLMA, were randomly allocated to either the GEB- or IT-guided techniques. After inserting the PLMA, alignment of the tip of the drain tube relative to the esophageal opening was verified by a fibrescope introduced through the drain tube. Placing the fibrescope through the PLMA identified the glottic structures. The primary endpoint indicating the proper alignment of the tip of the drain tube of the PLMA with the upper esophageal opening was the ability to pass the fibrescope into the esophagus through the drain tube by a distance >35 cm without obstruction and the ability to simultaneously visualize the esophageal mucosa. The overall success rates of PLMA insertion were similar in the GEB and IT groups. However, the mean airway insertion times were longer with the GEB than with the IT-PLMA. The GEB group achieved proper alignment of the drain tube and the upper esophageal opening more frequently than the IT group (97% confidence interval (CI(95)) 91.5-100% vs 81% CI(95) 68.5-93.5% of subjects, respectively; P = 0.027). When the GEB was used to place the PLMA, the patients' vocal cords were visualized more frequently than when the IT technique was used (100% vs 73% CI(95) 58.9-87.1% of subjects, respectively; P = 0.003). Fibreoptic bronchoscopy confirmed that GEB is superior to the IT technique in ensuring precise alignment of the tip of the drain tube of the PLMA with the upper esophageal opening. Accurate positioning may better preserve gastroesophageal drainage function of the PLMA.