An evaluation of indium DTPA chelate in the measurement of gastric emptying by scintiscanning

The sequential scintiscanning technique was used to determine gastric emptying rates in adult human subjects after ingestion of a meal of cornflakes and milk to which a gamma-emitting radioactive isotope had been added.

Comparison of emptying rates using ^113mIn DTPA chelate and ⁵¹Cr sodium chromate showed that significantly slower rates were recorded with chromate, and studies in vitro demonstrated adsorption of chromate to the solid component of the meal. The results imply that the liquid phase of the gastric contents after a meal is discharged through the pylorus more rapidly than the solid phase. Scintiscanning with indium chelate provides a measurement of the emptying of the liquid phase of the gastric contents.

     

The effect of preserving antral innervation and of a pyloroplasty on gastric emptying after vagotomy in man

A prospective randomized trial of 40 duodenal ulcer patients is reviewed. The patients had one of four operations (selective vagotomy, proximal gastric vagotomy, selective vagotomy plus pyloroplasty, or proximal gastric vagotomy plus pyloroplasty). The gastric emptying of a hypertonic fluid meal was assessed before and three to four months after operation. Selective vagotomy without a drainage procedure results in gastric retention and should no longer be considered as a method of treatment for duodenal ulcer. Proximal gastric vagotomy without a drainage procedure does not lead to gastric retention. Initial gastric emptying is more rapid after proximal gastric vagotomy but the final emptying time is the same as before operation and this operation alters the pattern of gastric emptying less than the other operations. Pyloroplasty added to either selective or proximal gastric vagotomy results in loss of the normal regulation of gastric emptying, very rapid initial gastric emptying, and a significant increase in the incidence of ;dumping'. It appears from these studies that ;dumping' is due to rapid gastric emptying and mainly due to the drainage procedure.     

Effect of sildenafil on gastric emptying in healthy adults

Background and Aim: Phosphodiesterase type 5 hydrolyzes and inactivates cyclic guanosine monophosphate produced by the nitric oxide‐stimulated guanylate cyclase. Sildenafil is a potent, reversible, and highly selective inhibitor of this phosphodiesterase. It causes smooth muscle relaxation by increasing intracellular concentrations of cyclic guanosine monophosphate. The aim of this study was to test the hypothesis that sildenafil alters gastric emptying and the intragastric distribution of food in healthy adults. Methods: Nine normal subjects (mean age 28 years, range 25–33) were given a placebo or a tablet of sildenafil (50 mg) at different times along with radio‐opaque markers. A gastric emptying scan was used to calculate the t_1/2 for gastric emptying (the time taken for the initial radioactivity to fall by 50%). Intragastric food distribution was also assessed using the gastric emptying scan to calculate proximal gastric emptying t_1/2, the proximal volume (the highest activity value in the proximal stomach at any time point in the study), and the distal volume (the highest activity value in the distal stomach at any time point in the study. Gastric emptying of an indigestible solid meal was assessed by calculating gastric clearance of radio‐opaque markers. Results: Sildenafil did not change total gastric emptying or gastric clearance of radio‐opaque markers. It shortened the proximal T_1/2, decreased proximal volume, and significantly increased distal volume. Conclusion: Sildenafil alters the intragastric distribution of food rather than causing gastric stasis.     

Cholecystokinin in the inhibition of gastric secretion and gastric emptying in humans

Cholecystokinin (CCK) is known to inhibit gastric acid secretion and gastric emptying but its physiological role in the inhibition of gastric functions is not settled. In this study performed on 16 young male subjects, gastric acid secretion and emptying rate were determined after intragastric administration of 8% peptone meal alone or in combination with intravenous infusion of graded doses of CCK-8 (5-80 pmol/kg.h) or with addition of vegetable oil to meal without or with pretreatment with loxiglumide, a specific CCK antagonist. CCK-8 infusion at lower dose (5 pmol/kg.h) was ineffective but at higher doses (20-80 pmol/kg.h) it resulted in a significant reduction in acid output by 39 and 43% and a decrease in gastric emptying from 54% to 40 and 22%, respectively. Pretreatment with loxiglumide abolished almost completely the inhibition of both gastric acid and gastric emptying by CCK-8. Fat added to peptone meal reduced gastric acid secretion by 42-65% and decreased gastric emptying to 24-32%. The pretreatment with loxiglumide tended to reduce fat-induced inhibition of gastric acid secretion and gastric emptying but the difference in the inhibition of gastric functions between the tests without and with loxiglumide was not significant. This study provides evidence that exogenous CCK administered at pharmacological doses is a potent inhibitor of gastric acid secretion and gastric emptying and probably acts via specific CCK receptors. In contrast, fat induces inhibition of gastric acid secretion and gastric emptying that cannot be fully attributed to hormonally acting CCK.     

Models of gastric emptying.

Some empirical and theoretical models of the emptying behaviour of the stomach are presented. The laws of Laplace, Hooke, and Poisseuille are used to derive a new model of gastric emptying. Published data on humans are used to test the model and evaluate empirical constants. It is shown that for meals with an initial volume of larger than or equal to 300 ml, the reciprocal of the cube root of the volume of meal remaining is proportional to the time the meal is in the stomach.For meals of initial volume of less than 300 ml the equation has to be corrected for the fact that the 'resting volume' of gastric contents is about 28 ml. The more exact formula is given in the text. As this model invokes no neural or hormonal factors, it is suggested that the gastric emptying response to the volume of a meal does not depend on these factors. The gastric emptying response to the composition of the meal does depend on such factors and a recent model of this process is used to evaluate an empirical constant.     

Early effects of peppermint oil on gastric emptying: a crossover study using a continuous real-time 13C breath test (BreathID system)

Background The aim of this study was to determine whether there was a correlation between peppermint oil and gastric emptying by using a novel noninvasive technique for measuring gastric emptying with a continuous real-time ¹³C breath test (BreathID system, Oridion, Israel). Methods Ten healthy male volunteers participated in this randomized, two-way crossover study. The subjects were randomly assigned to receive a test meal (200 kcal per 200 ml) containing 0.64 ml of peppermint oil or the test meal alone, after fasting overnight. A ¹³C-acetic acid breath test was continuously performed with the BreathID system, which monitors gastric emptying, for 4 h after the administration of the test meal. Using Oridion Research Software (β version), the time for emptying of 50% of the labeled meals (T 1/2), the analog to the scintigraphy lag time for 10% emptying of the labeled meal (T lag), the gastric emptying coefficient (GEC), and the regression-estimated constants (β and κ) were calculated. The parameters between two occasions were compared using the Wilcoxon signed-rank test. Results After peppermint oil intake, the T lag and β constant were significantly decreased. No significant differences in T 1/2, GEC, or κ were observed between the two occasions. Conclusions The decrease in the T lag and β constant suggests acceleration of gastric emptying during the early phase. This study showed that peppermint oil enhances gastric emptying, suggesting the potential use of peppermint oil in clinical settings for patients with functional gastrointestinal disorders.     

Determination of total gastric volume, gastric secretion and residual meal using the double sampling technique of George.

In literature several techniques are described for the measurement of gastric emptying. One of these is the double sampling technique of George which has the advantage that it enables multiple measurements of total gastric volume in one experiment. In order to estimate net gastric emptying, however, it is important to differentiate between the test meal volume present in the stomach and gastric secretion. In the present study George's technique was extended with a calculation procedure to estimate gastric secretion and net test meal outflow. An in vitro experiment was carried out which showed an accuracy of 5-10% for this method. An in vivo comparison was made with Hunt's chloride technique, which is used for estimating gastric secretion. Sixteen subjects participated in a 60 minute test with water as a test meal. Regression analysis showed a high degree of correlation (R2 = 0.99) between Hunt's method and the proposed method. The data obtained indicate that the proposed method gives a reliable estimation of net gastric emptying and is simple to do as no further measurements have to be carried out other than those needed for George's method.     

Study of gastric emptying using a ferromagnetic tracer.

A new ferromagnetic method for the measurement of gastric emptying is described. An inert tracer, magnesium ferrite, is added to a test meal. Its amount in the stomach is then measured at regular intervals by an external transducer using its ferromagnetic properties. The method is noninvasive and devoid of radiation exposure. The magnetic fields used are harmless. The feasibility, reliability, and reproducibility of the method are described. Gastric emptying was studied in 61 subjects. The shape of the gastric emptying curve conformed best to an exponential function. The mean half-time of gastric emptying was 49 +/- 17.4 min. In this limited series age and sex did not affect gastric emptying.     

Relative role of pyloroplasty size,truncal vagotomy,and milk meal volume in canine gastric emptying

The gastric emptying of 10, 20, or 40 ml/kg body mass milk meals was measured before and after Heineke-Mikulicz pyloroplasty of 3, 5, or 7 cm (6 dogs) or truncal vagotomy (3 dogs). The pyloroplasty group then underwent vagotomy, following which the tests were repeated. Initial gastric emptying (in the first 10 min) was increased after 5-and 7-cm pyloroplasties (P<0.01) and particularly after vagotomy with all sizes of pyloroplasty (P=0.001). Regardless of the volume of meal used, after vagotomy and pyloroplasty there was a 51–63% decrease in intragastric volume within the first 10 min. Increased duodenogastric reflux occurred in those dogs who showed rapid initial gastric emptying. After the first 10 min all groups were shown to have virtually normal gastric emptying, except the truncal vagotomy group in which gastric emptying was delayed (P<0.05). It is the combination of pyloroplasty with vagotomy which is required to produce the very rapid initial gastric emptying of a liquid meal following vagotomy with pyloroplasty. It is concluded that two mechanisms control the gastric emptying of a milk meal. The first acts quickly, is dependent on an intact pylorus, and is influenced by the intragastric volume; the second is a more slowly acting mechanism, requiring up to 10 min to have its effect, and is not dependent on an intact pylorus or the intragastric volume. After vagotomy and pyloroplasty, the speed of gastric emptying in the first 10 min is proportional to the original meal volume, and therefore the therapy of postvagotomy diarrhea and dumping with small frequent meals seems rational.This report is based on a PhD (Med) thesis presented to the University of the Witwatersrand, Johannesburg.This work was funded by the University of the Witwatersrand, Miller Foundation and Medical Research Council of South Africa.     

Slow gastric emptying induced by high fat content of meal accelerated by cisapride administered rectally

The evaluation of agents potentially accelerating gastric emptying in gastric stasis syndromes is time-consuming. Since a previous study showed that emptying is slowed after antecedent fat ingestion and intravenous cisapride abolishes this effect, we investigated whether emptying delayed by fat incorporated into a meal is reversed by cisapride and thus could serve as a model for such evaluations. Twelve healthy males received, under double-blind conditions, 30 mg cisapride rectally or placebo, and 3 hr thereafter a semisolid meal of low (9.2 g) or high (37.9 g) fat content. The sequence of combinations placebo/low-fat meal, placebo/high-fat meal, and cisapride/high-fat meal was randomized. Gastric emptying and antral motility were recorded scintigraphically. After placebo/high-fat, emptying was significantly slower (P<0.05) than after placebo/low-fat. After cisapride/high-fat, emptying was significantly faster (P<0.01) than after placebo/high-fat and similar to that after placebo/low-fat. Antral motility was little affected. The slow emptying of a high-fat meal thus seems a suitable model for the evaluation of prokinetic drug effects.     

Euglycaemic hyperinsulinaemia does not affect gastric emptying in Type I and Type II diabetes mellitus

Summary Hyperglycaemia slows gastric emptying in both normal subjects and patients with diabetes mellitus. The mechanisms mediating this effect, particularly the potential role of insulin, are uncertain. Hyperinsulinaemia has been reported to slow gastric emptying in normal subjects during euglycaemia. The purpose of this study was to evaluate the effect of euglycaemic hyperinsulinaemia on gastric emptying in Type I (insulin-dependent) and Type II (non-insulin-dependent) diabetes mellitus. In six patients with uncomplicated Type I and eight patients with uncomplicated Type II diabetes mellitus, measurements of gastric emptying were done on 2 separate days. No patients had gastrointestinal symptoms or cardiovascular autonomic neuropathy. The insulin infusion rate was 40 mU · m^–2· min^–1 on one day and 80 mU · m^–2· min^–1 on the other. Gastric emptying and intragastric meal distribution were measured using a scintigraphic technique for 3 h after ingestion of a mixed solid/liquid meal and results compared with a range established in normal volunteers. In both Type I and Type II patients the serum insulin concentration had no effect on gastric emptying or intragastric meal distribution of solids or liquids. When gastric emptying during insulin infusion rates of 40 mU · m^–2· min^–1 and 80 mU · m^–2· min^–1 were compared the solid T₅₀ was 137.8 ± 24.6 min vs 128.7 ± 24.3 min and liquid T₅₀ was 36.7 ± 19.4 min vs 40.4 ± 15.7 min in the Type I patients; the solid T₅₀ was 94.9 ± 19.1 vs 86.1 ± 10.7 min and liquid T₅₀ was 21.8 ± 6.9 min vs 21.8 ± 5.9 min in the Type II patients. We conclude that hyperinsulinaemia during euglycaemia has no notable effect on gastric emptying in patients with uncomplicated Type I and Type II diabetes; any effect of insulin on gastric emptying in patients with diabetes is likely to be minimal. [Diabetologia (1999) 42: 365–372] Received: 3 September 1998 and in revised form: 3 November 1998     

Influence of meal weight and caloric content on gastric emptying of meals in man

This study was designed to assess the relative influence of meal weight and caloric content on gastric emptying of liquid and solid meals in man. A dual radioisotopic method which permits noninvasive and simultaneous measurement of liquid-and solid-phase emptying by external gamma camera techniques was employed. Nine healthy volunteer subjects ingested 50-,300-, and 900-g lettuce and water meals adjusted to either 68, 208, or 633 kcal with added salad oil. The following observations were made: (1) absolute emptying rates (grams of solid food emptied from the stomach per minute) increased directly and significantly with meal weight; (2) increasing meal total caloric content significantly slowed solid food gastric emptying but did not overcome the enhancing effect of meal weight; and (3) liquid emptying rates were uninfluenced by meal total kcal amount.The authors wish to express their appreciation to the Salt Lake Veterans Medical Center, Medical Research Service for their support.     

Reevaluation of triethers as markers for triglycerides during gastric emptying

The validity of using triethers as markers for triglycerides during gastric emptying was investigated. Rats were given a lipid mixture containing [⁷⁵Se]triether plus [¹³¹I]triolein or [³H]triether plus [¹⁴C]triolein intragastrically. Similar studies were performed on humans using a homogenized test meal to which was added [⁷⁵Se]triether plus corn oil. Analysis of gastric contents at various time intervals after administration of the test meal did not show evidence of separation of triglyceride and triether in the stomach. It is discussed that the disappointing results of other workers using [³H]triether may be due to an artifact associated with instability of the tritium-to-triether bond in the preparation used.     

Effects of meal composition on gallbladder and gastric emptying in man

Cholecystogastric scintigraphy, utilizing [^99mTc]HlDA to label the gallbladder contents and [¹¹¹In]DTPA to label different meals, was utilized to determine the relationships between gallbladder and gastric emptying after meals of differing composition. Gallbladder emptying was determined in response to a multicomponent meal and to monocomponent fat, carbohydrate, and protein meals and in response to isotonic and hypertonic dextrose and isotonic and hypertonic saline. Also, the gallbladder emptying responses to equivalent multicomponent solid and liquid meals were compared. Significant gallbladder emptying was observed in response to the multicomponent meal and the monocomponent fat, carbohydrate, and protein meals. The most rapid and complete gallbladder emptying was seen with the multicomponent meal and the monocomponent fat meal. Significant gallbladder emptying was stimulated, not only by isotonic and hypertonic dextrose, but also by hypertonic saline. The gallbladder emptied more rapidly after a liquid than after a solid meal.     

Postcibal gastric emptying of pancreatin pellets: effects of dose and meal oil

To treat pancreatic exocrine insufficiency, physicians often prescribe enterically coated pellets of pancreatin to be taken with meals. The pellets are only partially effective in correcting the digestion and absorption of fat. We sought to determine in normal subjects whether emptying of pellets from the postcibal stomach was dose-related and whether the gastric emptying of lipophilic Creon-20 or Pancrease was altered by the presence or the absence of oil in a meal. Gastric emptying of pellets surface-labeled with ^113mIn or ^99mTc was followed with a gamma camera for 300 min after isocaloric meals. From our observations, we concluded that gastric emptying of 0.28–1.12 g of 1-mm or 2-mm pellets was dose-related (P < 0.01) and emptying of neither Creon-20 nor Pancrease was much affected by oil in the meal.     

Guar and gastric emptying in non-insulin dependent diabetes

Summary A gamma camera was used to measure gastric emptying in 10 non-insulin dependent diabetics and 10 control subjects during and after a breakfast meal of porridge labelled with^113mIn. In the diabetics there was a more rapid early phase and a more prolonged later phase of gastric emptying compared with controls. Incorporation of 10 g guar with the meal prolonged the later phase of gastric emptying in controls. However, guar did not significantly alter gastric emptying in the diabetics, although postprandial plasma glucose concentrations were reduced. The study demonstrates abnormalities of both the early and later phases of gastric emptying in an unselected group of non-insulin dependent diabetics. Guar reduced plasma glucose concentrations without affecting gastric emptying in these patients.     

Pectin delays gastric emptying and increases satiety in obese subjects

As pectin delays gastric emptying in normal subjects and satiety may be linked to the rate of gastric emptying, we designed this study to evaluate, in a group of obese subjects, the effect of adding pectin to a meal on gastric emptying, sensation of satiety, and postprandial plasma cholecystokinin and pancreatic polypeptide levels. We studied gastric emptying of solids in 9 adult obese subjects on 2 separate days in a randomized fashion. On day 1, 15 g of pectin was added to the meal, and on day 2 15 g of methylcellulose was added and served as control. Satiety was evaluated by an analogue rating scale. Pectin significantly delayed gastric emptying time [t1/2 = 116 +/- 23 min vs. 71 +/- 17 min observed with methylcellulose (p less than 0.001)]. Pectin also significantly increased subjects' sensation of satiety [98 +/- 7 vs. 74 +/- 17 (p less than 0.001)]. Postprandial release of cholecystokinin and pancreatic polypeptide was not modified by pectin. As pectin induces satiety and delays gastric emptying in obese patients, it may be a useful adjuvant in the treatment of disorders of overeating.     

Gastrointestinal motility and gastric emptying after Billroth II gastrectomy in dogs

This study was undertaken to compare the effects of subtotal Billroth II gastrectomy on gastric emptying and gastrointestinal motility with previously published results in intact dogs and in dogs with subtotal Roux-Y gastrectomy. Extraluminal strain gauge transducers were used to study gastrointestinal motility after Billroth II gastrectomy in four conscious dogs. Gastric emptying was measured radiographically. In Billroth II dogs gastric emptying of low-viscosity meals was biphasic with an initial rapid emptying. The addition of nutrients to low-viscosity meals delayed gastric emptying accompanied with reduction in gastric and jejunal motility. Similar to that in Roux-Y dogs, gastric emptying of noncaloric medium-viscosity meals was delayed because of segmenting motor patterns of the jejunal loops, in contrast to the propulsive jejunal motor pattern in intact dogs. Nutrients added to medium-viscosity meals did not change the jejunal motor pattern; gastric emptying was delayed compared with intact dogs. Results show that meal viscosity and jejunal motor pattern influence gastric emptying after Billroth II gastrectomy.This study was supported by the Deutsche Forschungsgemeinschaft, grant Eh 64/3-2.     

Measurement of gastric functions during digestion of ordinary solid meals in man.

A method of measuring gastric secretions and emptying rates after ingestion of an ordinary (solid-liquid) meal has been developed and validated. The technique quantifies movements of volume across the pylorus using constant duodenal perfusion with a nonabsorbable marker, polyethylene glycol (PEG), which, in turn, quantifies emptying into the duodenum of another marker, [14C]PEG, incorporated in the meal. Acid and pepsin outputs can be determined without manipulation of the intragastric pH. Employing this method, we have simultaneously quantified acid, pepsin, and total secretory outputs; rates of gastric emptying of meal and secretions; and serum gastrin levels during digestion. These data characterize physiological responses to ordinary food in health.     

Relationship between gastric and gallbladder emptying and refilling in normal subjects and patients withH. pylori-positive and-negative idiopathic dyspepsia and correlation with symptoms

Gastric and gallbladder emptying and refilling was studied in 10 normal subjects and in 38 dyspeptic patients.H. pylori was determined in each dyspeptic on mucosal antral biopsy performed during endoscopy. Gastric and gallbladder emptying was evaluated by real-time ultrasonography. Normal subjects were evaluated after two solid-liquid meals of 340 kcal and 680 kcal. Dyspeptics were studied after the 340-kcal meal only. For each subject and patient, minimum gallbladder volume and percentage of gastric emptying at this point was determined. Gastric and gallbladder slope was also drawn, and the crossing point between the two slopes identified. In normal subjects with the 340-kcal and 680-kcal meal, minimum gallbladder volume occurred for a similar percentage of gastric emptying. The crossing point between the two slopes was computed at the same percentage of gastric and gallbladder refilling with both meals. With the 680-kcal meal, however, peak gallbladder contraction and the crossing point between the two slopes occurred significantly later than with the 340-kcal meal (P<0.05). In dyspeptics with the 340-kcal meal, the parameters evaluated were similar to the ones computed in controls after the meal of 680-kcal, suggesting delayed gastric emptying and gallbladder refilling. The presence or absence ofH. pylori and symptom score were not correlated with any of the parameters studied.