Effect of gum chewing on gastric volume and emptying: a prospective randomized crossover study.

ABSTRACT

BACKGROUND: Current fasting guidelines allow oral intake of water up to 2 h before induction of anaesthesia. We assessed whether gum chewing affects gastric emptying of 250 ml water and residual gastric fluid volume measured 2 h after ingestion of water. METHODS: This prospective randomized observer-blind crossover trial was performed on 20 healthy volunteers who attended two separate study sessions Control and Chewing gum (chlorophyll flavour, with 2.1 g carbohydrate). Each session started with an ultrasound measurement of the antral area, followed by drinking 250 ml water. Then, volunteers either chewed a sugared gum for 45 min (Chewing gum) or did not (Control). Serial measurements of the antral area were performed during 120 min, and the half-time to gastric emptying (t½), total gastric emptying time, and gastric fluid volume before ingestion of water and 120 min later were calculated. RESULTS: Gastric emptying of water was not different between sessions; the mean (sdsd) t½ was 23 (10) min in the Control session and 21 (7) min in the Chewing gum session (P=0.52). There was no significant difference between sessions in gastric fluid volumes measured before ingestion of water and 120 min later. CONCLUSIONS: Chewing gum does not affect gastric emptying of water and does not change gastric fluid volume measured 2 h after ingestion of water. CLINICAL TRIAL REGISTRATION NCT02673307.