摘要目的:评价左侧喉旁按压联合环状软骨按压预防面罩正压通气时胃进气的效果。方法:选择择期行气管插管全麻手术患者240例，年龄18~75岁，性别不限，ASA分级Ⅰ或Ⅱ级，采用随机数字表法分为4组( n＝60)：环状软骨按压组(CP组)、左侧喉旁按压组(LP组)、环状软骨联合左侧喉旁按压组(CP+LP组)和对照组(C组)。于麻醉诱导前采用超声测量胃窦横截面积(CSA)，采用吸气压力为25 cmH 2O的压控模式下面罩通气，4组患者分别施加不同手法进行处理，3 min后再次测量胃窦CSA。记录通气前后胃窦CSA及其差值；记录通气后超声检查胃进气发生情况。 结果:与通气前比较，C组、CP组和LP组通气后胃窦CSA增大( P<0.01)，CP+LP组通气后胃窦CSA差异无统计学意义( P>0.05)。C组、CP组、LP组和CP+LP组胃窦CSA差值依次减小( P<0.05或0.01)。C组、CP组、LP组和CP+LP组胃进气发生率分别为53%、30%、12%和0。与C组比较，LP组和CP+LP组胃进气发生率降低( P<0.05)，CP组差异无统计学意义( P>0.05)；与CP组比较，CP+LP组胃进气发生率降低( P<0.05)，LP组差异无统计学意义( P>0.05)。 结论:左侧喉旁联合环状软骨按压可有效预防面罩正压通气时胃进气的发生。

abstractsObjective:To compare the efficacy of left parapharyngeal pressure (PLP) combined with cricoid pressure in preventing gastric insufflation during positive pressure ventilation by facemask.Methods:Two hundred and forty patients of both sexes, aged 18-75 yr, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, undergoing surgery under general anesthesia requiring endotracheal intubation, were selected and randomly divided into 4 groups ( n=60 each) using a random number table method: cricoid pressure group (group CP), left PLP group (group LP), cricoid pressure combined with left PLP7 group (group CP+ LP), and control group (group C). The gastric antrum cross-sectional area (CSA) was measured by ultrasound in all the patients before induction of anesthesia, and facemask ventilation in pressure-controlled mode with suction pressure of 25 cmH 2O was applied, the patients in 4 groups were treated with different manipulations, and 3 min later the CSA of gastric antrum was measured again.The gastric antrum CSA before and after ventilation and the difference were recorded.The occurrence of gastric insufflation was examined by ultrasound after ventilation. Results:Compared with the baseline before ventilation, the CSA of gastric antrum was increased after ventilation in C, CP and LP groups ( P<0.01), and no significant change was found in the CSA after ventilation in CP+ LP group ( P>0.05). The difference of gastric antrum CSA was decreased in turn in C, CP, LP and CP+ LP groups ( P<0.05 or 0.01). The incidence of gastric insufflation were 53%, 30%, 12% and 0 in C, CP, LP and CP+ LP groups, respectively.Compared with group C, the incidence of gastric insufflation was significantly decreased in LP and CP+ LP groups ( P<0.05), and no significant change was found in group CP ( P>0.05). Compared with group CP, the incidence of gastric insufflation was significantly decreased in group CP+ LP ( P<0.05), and no significant change was found in group LP ( P>0.05). Conclusion:The combination of left PLP and cricoid pressure can effectively prevent gastric insufflation during positive pressure ventilation by facemask.