The Cricoid Force Necessary to Occlude the Esophageal Entrance: Is There a Gender Difference?

60 (30 men; ages 18 - 50 yr; body mass index < 28 kg/m2 physical status 1, 2 patients were recruited for the study. These patients were to undergo general anesthesia with tracheal intubation. starting force was 20 N in both sex. These forces were standardized by reproducing a new device : cricometer. The sequence of the applied forces was done by using the up and down method in both sex. After preoxygenation, anesthetic induction, muscular relaxation and mask ventilation, the study commenced. Direct laryngoscopy using the Glidescope video laryngoscope was performed and the view of the glottis and the esophageal entrance was video recorded with each CF. 2 attempts to insert a lubricated gastric tube (GT; size 20 F, 12 F) were carried out by a "blinded" operator in each patient. A successful insertion of the GT indicated a patent esophagus. When this occurred while CP was applied, it indicated ineffective CP. An unsuccessful insertion of the GT while CP was applied indicated a non-patent esophagus (effective CP). The position of the esophageal entrance relative to the glottis during CP was assessed from the video recordings.