title: Stepped assessment of gastric emptying of a solid meal using the (13)C-octanoic acid breath test.
abstract: The (13)C-octanoic acid breath test is widely used for evaluating gastric emptying of solids. Since the results of this test are influenced by multiple factors such as the time required to grind the solid meal into smaller particles, the gastroduodenal transport time of the ground meal, and the time required for bowel drug absorption and drug dispersion, the administration of a test meal by the oral route alone cannot result in an accurate measurement of the complicated process of emptying the stomach of solids. The aim of the present study was to evaluate each phase of gastric emptying of solids by varying the administration route of the test meal. Six healthy male volunteers (mean age: 33.2 yr) participated in the study. The test meal consisted of a bowl of rice topped with a mixture of boiled chicken and eggs admixed with 100 mg of (13)C-octanoic acid (total: 273 kcal). All subjects were given the test meal by each of the following three methods: 1. Normal oral intake of the test meal, 2. Feeding of the ground test meal through a nasogastric tube, 3. Feeding of the ground test meal through a duodenal tube. For each set of examinations, the mean residence time (MRT), half-emptying time (T(1/2)), gastric emptying coefficient (GEC), lag phase (L-breath), and measured maximum (13)C excretion time (Tmax-measured) were calculated. The data was analyzed to determine the time for each phase of gastric emptying as follows: mean grinding time (MGT) = MRT(oral) - MRT(nasogastric), mean gastroduodenal transport time (MGDTT) = MRT(nasogastric) - MRT (nasoduodenal). Data was expressed as the mean +/- SE. The values of the parameters of MGT were 0.82 +/- 0.50 hr (MRT), 0.64 +/- 0.18 hr (T(1/2)), 0.51 +/- 0.24 hr (L-breath), -0.45 +/- 0.30 hr (GEC), and 49.2 +/- 8.0 min (Tmax-measured). The values of the parameters of MGDTT were 0.87 +/- 0.38 hr (MRT), 0.26 +/- 0.29 hr (T(1/2)), 0.92 +/- 0.36 hr (L-breath), 0.55 +/- 0.23 hr (GEC), and 63.33 +/- 8.16 min (Tmax-measured). The times required for the drug absorption and disposition were 1.60 0.20 hr (MRT), 1.03 +/- 0.24 hr (T(1/2)), 0.10 +/- 0.08 hr (L-breath), 3.72 +/- 0.46 hr (GEC), and 19.67 +/- 2.11 min (Tmax-measured). By varying the administration route of a test meal containing (13)C-octanoic acid, we may be able to assess each phase of the emptying of gastric solids in detail, thus leading to a better understanding of gastroduodenal motility.
authors.affiliation: Division of Endoscopy and Ultrasound, Department of Clinical Pathology and Laboratory Medicine, Kawasaki Medical School, Matsushima 577, Kurashiki 701-0192, Japan. kusunoki@med.kawasaki-m.ac.jp
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kusunoki
authors.forename: Jiro
authors.initials: J
authors.lastname: Hata
authors.forename: Shinya
authors.initials: S
authors.lastname: Aoki
authors.forename: Tomoari
authors.initials: T
authors.lastname: Kamada
authors.forename: Manabu
authors.initials: M
authors.lastname: Ishii
authors.forename: Motonori
authors.initials: M
authors.lastname: Sato
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Tanaka
authors.forename: Noriaki
authors.initials: N
authors.lastname: Manabe
authors.forename: Akiko
authors.initials: A
authors.lastname: Shiotani
authors.forename: Shigeto
authors.initials: S
authors.lastname: Yoshida
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
authors.forename: Ken
authors.initials: K
authors.lastname: Haruma
mesh_terms: D000328:Adult; D001944:Breath Tests / Q000379:methods*; D002210:Caprylates / Q000493:pharmacokinetics*; D002247:Carbon Isotopes; D004435:Eating / Q000502:physiology*; D005746:Gastric Emptying / Q000502:physiology*; D005769:Gastrointestinal Motility / Q000502:physiology; D006801:Humans; D008297:Male
chemical_list: D002210:Caprylates; D002247:Carbon Isotopes; C031492:octanoic acid