THE EFFECTS OF CHEWING GUM ON GASTRIC-CONTENT PRIOR TO INDUCTION OF GENERAL-ANESTHESIA

To study the effects on gastric content and subjective well being of c hewing gum in the immediate preoperative period, 60 female nonsmokers were randomized to use regular, sugar-free chewing gum preoperatively or to continue the overnight fast. In a similar fashion 44 habitual sm okers were randomized to use nicotine gum 2 mg or not. Nonsmokers usin g chewing gum had significantly larger gastric fluid volumes than cont rols (mean 30 +/- 19 mL vs 20 +/- 15 mL; 95% confidence interval (CI) for difference 1-19 mL; P = 0.03), with no difference in gastric fluid acidity. In smokers, neither gastric fluid volume nor acidity differe d significantly between those who were or were not chewing gum. Althou gh the use of nicotine gum in smokers was associated with a reduction in dryness of the mouth, thirst, and irritability, nonsmokers chewing regular gum did not report significant improvements in patient well be ing. In habitual smokers unable to abstain from nicotine, the use of n icotine gum on the morning of surgery may be beneficial. Although it i s difficult to prove a direct influence on the incidence of pulmonary aspiration of increased gastric contents, the fact that regular, sugar -free chewing gum increased gastric fluid volumes probably means that it should not be used on the morning of surgery.