Efficacy of left parapharyngeal pressure combined with cricoid pressure in preventing gastric insufflation during positive pressure ventilation by facemask / 中华麻醉学杂志

ABSTRACT

Objective: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.