Abstract:Objective To explore the safety of 2-hour no drinking water before gastroscopy.Methods 180 volunteers were randomly divided into observation group A (drinking 500.00 mL of water), observation group B (drinking water more than 500.00 mL) and control group C (no drinking water for more than 8 hours). After drinking water, the gastric fluid volume of the observation group was measured every 15.00 min by abdominal color doppler ultrasound until gastric emptying, then a gastroscopy was performed, the residual fluid is sucked up with the gastroscopy and measured in a measuring cup. The amount of residual fluid, completion rate and the incidence of aspiration were compared among the three groups.Results The gastric emptying time of observation group A was 15.00~75.00 min, 39.81 min on average, the residual fluid amount was 5.00~50.00 mL, 20.38 mL on average; The gastric emptying time of observation group B was 15.00~75.00 min, 40.38 min on average, the residual fluid amount was 10.00~60.00 mL, 24.81 mL on average. The residual fluid amount of the control group C was 0.00~60.00 mL, 25.95 mL on average. All the volunteers completed the examination, and no aspiration occurred during the examination. The difference was not statistically significant (P > 0.05).Conclusion Drinking water for less than 1 000.00 mL can be emptied within 75 min in volunteers with no emptying disorder. It is safe and feasible of 2-hour no drinking water before gastroscopy.