Their second criticism is that our use of the GlideScope Video Laryngoscope (GVL) prevents the extrapolation of our findings to the use of rigid laryngoscopy. They assert that the use of GVL can result in a change in the laryngeal-esophageal anatomical relationship. We believe this is a moot point for 3 reasons. First, our study was performed in the sniffing position, which is the ideal position for axis alignment. Second, the GVL yields a panoramic view of the glottis and esophageal entrance and permits easy cannulation of the esophagus.3 Third, we believe that, in the future, the use of video laryngoscopy will surpass the use of conventional laryngoscopy.
Their third criticism is that failed gastric tube insertion during CP is not proof of effective CP. It is clearly mentioned in the Methods section that in all patients in whom esophageal cannulation could not be done (effective CP), cannulation was attempted again after the release of CP and was successfully performed. This was an important part of the protocol to ensure that the inability to cannulate was solely due to CP and not because of other causes. Thirteen of 73 patients were excluded, and the reason for this was because of the prolonged time required to visualize the esophageal inlet. Our goal was to complete the experiment in <2 minutes in our anesthetized and paralyzed patients. For safety concerns, when it became apparent that the experiment would last longer than 2 minutes (because of the time required to identify the esophageal inlet in some patients), the experiment was terminated.
Regarding their fourth criticism, we believe our investigation provided evidence that the cricoid force necessary to prevent regurgitation is less in women compared with men with normal body habitus. The fact that the cricoid cartilage is smaller in women as compared with men was adequately addressed in our article. We are satisfied with our explanation that less applied cricoid force occludes the esophageal entrance in women as compared with men is related to the differences in the size of the cricoid plate.
It is clearly stated in the Methods sections of our 2 articles1,3 that training of the operator performing gastric tube insertion trials commenced months before the studies began. In addition, it is has been shown in a randomized clinical trial that the glidescope facilitates gastric tube insertions.4 It is no surprise that ignoring these important aspects of our strict protocol has led the Italian group to incorrect or misleading conclusions.