Effects of cigarette smoking on solid and liquid intragastric distribution and gastric emptying

Background: The acute effects of cigarette smoking on gastric emptying are controversial, whereas its effects on the intragastric distribution of solids and liquids are not established. Methods: Dual isotope gastric scintigraphy was performed in 15 habitual smokers (studied twice, either sham smoking or actively smoking) and in 15 age- and sex-matched nonsmokers. Results: Acute smoking was associated with an increased prevalence of episodes of retrograde intragastric movement of solids (3 of 15 sham subjects vs. 12 of 15 actively smoking subjects; P < 0.01) and of liquids (0 of 15 vs. 7 of 15; P < 0.01) from distal to proximal stomach. Fundal half-emptying time (T 1 2) for liquids was also prolonged by smoking (43 ± 19 minutes sham vs. 125 ± 216 minutes active; P < 0.05). Acute smoking delayed solid lag time (13 ± 6 minutes sham vs. 32 ± 18 active; P < 0.05) and liquid T 1 2 (46 ± 21 vs. 90 ± 50 minutes; P < 0.05). In the nonsmokers, such episodes of proximal intragastric redistribution did not occur, and intragastric and overall emptying parameters did not differ significantly from those of habitual sham smokers. Conclusions: Acute cigarette smoking produces excessive antrofundal redistribution of both solid and liquid contents and delays solid and liquid gastric emptying.