The ¹³C-octanoic acid breath test has been thought to be one of the most important methods in gastric emptying, because it is non-invasive and needs no special device. In this study, we evaluated the gastric emptying results between the ¹³C-octanoic acid breath tests, scintigraphy, and acetaminophen method. Ten patients with non-ulcer dyspepsia and 4 healthy volunteers were studied. For the test meal, we used scrambled egg, white bread, and 150 ml water and into the scrambled egg, 100 mg of ¹³C-octanoic acid, 37 MBq 99mTc-DTPA, and 20 mg/kg body weight of acetaminophen were mixed. After eating, breath samples and scanning scintigraphic information was obtained up to 8 and 2 hours, respectively. Blood sample was obtained 45 minutes after eating and the concentration of serum acetaminophen were measured. Previously, a positive correlation between the half emptying time (t_1/2) determined by breath test and scintigraphy, was reported by Ghoos et al.(1993) (y=1.12x+66.1, R²=0.79, p<0.0001) and in this study a positive correlation was found (y =0.76x +113, R²=0.29, p=0.047). There was a negative correlation between the t, 12 determined by scintigraphy and the concentration of serum acetaminophen (y=-0.12x+15.9, R²=0.40, p=0.013). In case of that ¹³CO₂ excretion of breath test was remained, even 8 hours after eating, t_1/2 and lag phase determined by breath test were more delayed than actual state. In case of that ¹³CO₂ excretion curve in early phase was drawn like sigmoid curve, t_1/2 determined by breath test were more delayed than actual state. In case of that ¹³CO₂ excretion curve had two peak-points, there was no problem. In conclusion the ¹³C octanoic acid breath test is a promising and reliable method for measuring gastric emptying.

抄録全体を表示

Background: ¹³C-acetate breath test (ABT) has been proposed as a noninvasive and nonradioactive technique for measuring gastric emptying. A variety of test meals have been used for the ABT. Since a standardized test meal that is easily prepared and inexpensive would be helpful for using ABT as a clinical test, we use a liquid test meal in screening for gastrointestinal motility disorders. Studies comparing ABT results after administrating a variety of liquid test meals are lacking. The aims of this study were to compare the gastric emptying indexes obtained by ABT after ingestion of three kinds of test meals with different fat and caloric content.
Patients and Methods: Ten healthy subjects, 7 women and 3 men, aged 25-51 years, volunteered for this study. None of them complained of gastrointestinal symptoms, was taking any drugs or was a smoker. Each subject was studied three times, with a 1-week interval between tests. RACOL (200 kcal, protein 8.76 g, fat 4.46 g, glucose 31.24 g), Ensure Liquid (200 kcal, protein 7.04 g, fat 7.04 g, glucose 27.4 g), and Ensure Hi (300 kcal, protein 10.56 g, fat 10.56 g, glucose 41.2 g) were given in randomized order. Breath samples were collected at 5, 10, 15, 20, 30, 40, 50, 60, 75, 90, 105, 120, 135, 150, 165, 180, 210, and 240 min. ¹³C was measured as the ¹³CO₂/¹²CO₂ isotope ratio and was expressed as delta over baseline per mil. The results of ABT, gastric emptying, were expressed as the time of peak excretion (T_max) and half emptying time (T_1/2) calculated using the Solver procedure in Excel 2000 (Microsoft).
Results: The mean values of T_max were 0.99, 0.85, and 1.05 hours after ingestion of RACOL, Ensure Liquid, and Ensure Hi, respectively. The mean values of T_1/2 were 1.53, 1.35, and 1.65 hours, respectively. Increasing the meal caloric content resulted in significantly longer half emptying time, whereas increasing the fat content had little effect on gastric emptying assessed by ABT using liquid test meals.
Conclusions: In healthy subjects, caloric intake is a major determinant of gastric emptying rate.

抄録全体を表示

We investigated some important points to standardize ¹³C breath test for gastric emptying. The ¹³CO₂ infrared spectrophotometry analyzer for ¹³C urea breath test to diagnose helicobacter pylori infection needed two breath samples which were collected before and after taking ¹³C substance to measure Δ value. We used a few big sampling bags to collect breath samples before taking test meal. The Δ value between two breath samples collected without ¹³C substance was very small. So there was no problem to regard separate breath samples as same ¹³CO₂ concentration. Deep breathing and using big sampling bag did not influenced because total CO₂ concentration of breath sample was not influenced the Δ value when CO₂ concentration was more than 2%. Therefore the ¹³CO₂ infrared spectrophotometry analyzer was useful to measure breath samples of ¹³C breath test for gastric emptying. Previous studies usually used the half emptying time as a parameter to assume gastric emptying. Recently, the maximum ¹³C excretion time was reported as a good parameter to assume gastric emptying. But in ¹³C-octanoate breath test for solids test meal, the half emptying time and the maximum ¹³C excretion time were considered parameters which were influenced by absorption, metabolism and excretion because there were strong correlations between the total cumulative ¹³C recovery and these parameters. Reproducibility of the parameters in ¹³C-acetate breath test for liquids were better than those in ¹³C-octanoate breath test for solids. So we considered that ¹³C-acetate breath test measured by the ¹³CO₂ infrared spectrophotometry analyzer was a standard method of 13C breath test for gastric emptying and that the maximum ¹³C excretion time was more useful parameter than other parameters. To simplify ¹³C breath test for gastric emptying, we considered to need more studies of normal subjects and patients.

抄録全体を表示

There have been many studies about the diagnosis of gastric emptying using ¹³C octanoic acid breath test (¹³C-OABT) since 1993 when Ghoos el al.(1993) first reported, and various index of ¹³C-OABT was investigated for the correct diagnosis. Especially, the half empting time (T_1/2) calculated from fitting curve and the maximum peak time (T_max) obtained by the actual ¹³C-excreation curve are used most frequently. However, some discrepancy between T_1/2 and T_max in the same subject is observed. In this report, we compared T_1/2 with T_max and discussed usefulness and problems of ¹³C-OABT. Subjects were 20 healthy volunteers and 55 patients with suspect of delayed gastric empting ; 50 with Diabetes Mellitus and 5 with functional dyspepsia. The subjects consumed a standard 280 kcal test meal consisting of 100 mg of ¹³C-octanoic acid. Breath samples were obtained before and every 15 min. after the consuming of test meal for a total of 6h. Correlation between T_1/2 and T_max was examined. As results, a significant correlation between T_1/2 and T_max was observed (γ=0.84). However, the diagnosis of T_1/2 did not agree with that of T_max in 29.7% ; 15 of 37 patients diagnosed as delayed gastric emptying by T_1/2 were judged normal by T_max. The ¹³C-excreation curve of these 15 patients showed delayed recovery in late phase. We speculated this delayed recovery did not result in true delayed gastric emptying but was the consequence of metabolic effect probably due to liver function. If so, the diagnosis using Tmax is considered more accurate than that using T_1/2 in ¹³C-OABT, however requiring further study to confirm this speculation.

抄録全体を表示

われわれ¹³C懇話会は呼気試験の標準化を目的に結成され, 今回液体食を用いた試案を作成した.われわれはこの試案のサンプリングポイントの妥当性を評価検討した.方法は¹³C-acetate 100mgを加えたラコール200ml (200kcal) を試験食とし, 呼気を試案 (18point;5, 10, 15, 20, 30, 40, 50, 60, 75, 90, 105, 120, 135, 150, 165, 180, 210, 240分後) の如く採取し, サンプリングポイントを変えた2つの方法 (10point, 24point) と比較した.評価項目は本邦で頻用される7つのパラメータ (m値, AUC, MRT, T_max (実測値), T_1/2, lag phase, GEC) を用いた.試案のパラメータは比較した2つの方法とほぼ同じであり, サンプリングポイントの妥当性が証明された.これは簡便化の観点からは, 呼気採取ポイントを10pointに削減可能であることも示す結果であり, 従来のパラメータを用いて総合的に評価する場合は, 10point程度は呼気採取が必要と考えられた.胃切除後の症例ではサンプリングポイントに関わらず実測値とのきれいなfitting carveは描けず, パラメータを用いた評価は困難と思われた.

抄録全体を表示

非侵襲的な固形食の胃排出検査法として¹³C-octanoi cacid呼気試験が用いられつつある.われわれはこれまで超音波法を, 非侵襲的な胃運動機能検査法として臨床応用してきたが, 今回呼気試験と超音波法の二つの結果を比較した.17名のFunctiollal dyspepsia (FD) 患者と10名の健常人を対象とした.¹³C-octanoic acid 100mgを加えた卵黄でスクランブルエッグを作り, ご飯の上にのせた後市販の親子丼の素をかけて424kcalの固形試験食とした.試験食を摂取後, 超音波法は座位で3時間まで15分間隔で観察し排出曲線を描いた.呼気試験は3時間までを超音波法と同じ15分間隔で, 3時間から6時間までを30分間隔で呼気を採取し, 赤外線分光機を用いて¹³CO₂を測定した.両試験の共通した排出動態指標であるT_1/2とlag phaseを比較検討したが, 呼気試験のT_1/2と超音波法のT_1/2はγ²=0.638と強い相関を示したが, 両者の結果が一致する訳ではなかった.T_1/2とlag phaseは共にFD患者で健常人より延長していた.呼気試験と超音波法の胃内残存率曲線は一致する傾向にはあったが, 超音波法でのばらつきが大きかった.

抄録全体を表示