Intraesophageal pressure, es ophageal insufflation testing, esophageal BaM perspective and laryngofiberscopy were carried out, respectively. Results The mean pressure, 1cm bel ow the entranc e of esophagus in the two groups, was 5 mmHg.

• 结果食管入口下1cm处,测得两组平均压力均为5mmHg。