Assessment Of Gastric Emptying Research Articles

Determination of fundic accommodation in gastric emptying scintigraphy. Evaluation of its clinical usefulness

AimGastric emptying scintigraphy is used to assess patients with symptoms of dyspepsia or gastroparesis. An alteration of fundus accommodation may explain these symptoms. The aim of this study was to determine the accommodation in gastric emptying scintigraphy studies performed in our institution. Material and methods50 patients (43 children) referred for gastric emptying assessment were evaluated. After fasting for 8 h, and following international guidelines, egg labeling was performed with 37 mBq of [99mTc]Tc-DTPA and administration of standardized food. Areas of interest were defined in the stomach at different times, and the corresponding retention percentages were calculated. Considering the image at time zero, gastric accommodation was qualitatively and quantitatively assessed, calculating the ratio between proximal stomach counts and total counts. ResultsOf the 50 patients studied, 32 had normal emptying, 10 had slowed emptying and 8 had accelerated emptying. Within the group of patients with normal emptying, 8 had altered accommodation (25%) and another 8 in the group with abnormal emptying (44%). Applying the ROC curve analysis to quantitative values, the most appropriate cut-off value was 0.785 with p < 0.001, sensitivity 82.4% and specificity 100%. ConclusionGastric emptying scintigraphy in addition to determining motility, made it possible to assess both qualitatively and quantitatively the distribution of the radiotracer in the stomach and thus, indirectly, the accommodation in the fundus. It provided added diagnostic information in a simple manner, without protocol changes and allowing more specific treatments to be assessed.

Determinación de la acomodación fúndica en gammagrafía de vaciamiento gástrico. Valoración de su utilidad clínica

AimGastric emptying scintigraphy is used to assess patients with symptoms of dyspepsia or gastroparesis. An alteration of fundus accommodation may explain these symptoms. The aim of this study was to determine the accommodation in gastric emptying scintigraphy studies performed in our institution. Material and methods50 patients (43 children) referred for gastric emptying assessment were evaluated. After fasting for 8hours, and following international guidelines, egg labeling was performed with 37 mBq of [99mTc]Tc-DTPA and administration of standardized food. Areas of interest were defined in the stomach at different times, and the corresponding retention percentages were calculated. Considering the image at time zero, gastric accommodation was qualitatively and quantitatively assessed, calculating the ratio between proximal stomach counts and total counts. ResultsOf the 50 patients studied, 32 had normal emptying, 10 had slowed emptying and 8 had accelerated emptying. Within the group of patients with normal emptying, 8 had altered accommodation (25%) and another 8 in the group with abnormal emptying (44%). Applying the ROC curve analysis to quantitative values, the most appropriate cut-off value was 0.785 with p<0.001, sensitivity 82.4% and specificity 100%. ConclusionGastric emptying scintigraphy in addition to determining motility, made it possible to assess both qualitatively and quantitatively the distribution of the radiotracer in the stomach and thus, indirectly, the accommodation in the fundus. It provided added diagnostic information in a simple manner, without protocol changes and allowing more specific treatments to be assessed.

Gastric emptying is slower in women than men with type 2 diabetes and impacts on postprandial glycaemia.

To evaluate sex differences in gastric emptying and the glycaemic response to a glucose drink and a high carbohydrate meal in type 2 diabetes (T2D). In cohort 1, 70 newly diagnosed, treatment-naïve Chinese patients with T2D (44 men) recruited from a diabetes outpatient clinic ingested a 75-g glucose drink containing 150 mg 13C-acetate. In cohort 2, 101 Australian patients with T2D (67 male) recruited from the community, managed by diet and/or metformin monotherapy, ingested a semi-solid mashed potato meal, labelled with 100 μl 13C-octanoic acid. Breath samples were collected over 3 and 4 h, respectively, for assessment of gastric emptying, and venous blood was sampled for evaluation of glycaemia (with and without adjustment for each participant's estimated total blood volume). Gastric emptying was slower in female than male subjects in both cohorts (both p < .01). Multiple linear regression analyses revealed that gastric emptying was independently associated with sex (both p < .05). Without adjustment for blood volume, the glycaemic responses to oral glucose and the mixed meal were greater in female subjects (both p < .001). However, after adjustment for blood volume, the glycaemic responses were greater in men (both p < .05). Gastric emptying is slower in women than men with T2D, associated with a reduced blood volume-adjusted glycaemic response to oral glucose and a mixed meal in women. These observations highlight the sex difference in postprandial glucose handling, which is relevant to the personalized management of postprandial glycaemia in T2D.

Deuterium body array for the simultaneous measurement of hepatic and renal glucose metabolism and gastric emptying with dynamic 3D deuterium metabolic imaging at 7 T.

Deuterium metabolic imaging (DMI) is a novel noninvasive method to assess tissue metabolism and organ (patho)physiology in vivo using deuterated substrates, such as [6,6'-2 H2 ]-glucose. The liver and kidneys play a central role in whole-body glucose homeostasis, and in type 2 diabetes, both hepatic and renal glucose metabolism are dysregulated. Diabetes is also associated with gastric emptying abnormalities. In this study, we developed a four-channel 2 H transmit/receive body array coil for DMI in the human abdomen at 7T and assessed its performance. In addition, the feasibility of simultaneously measuring gastric emptying, and hepatic and renal glucose uptake and metabolism with dynamic 3D DMI upon administration of deuterated glucose, was investigated. Simulated and measured B1 + patterns were in good agreement. The intrasession variability of the natural abundance deuterated water signal in the liver and right kidney, measured in nine healthy volunteers, was 5.6% ± 0.9% and 4.9% ± 0.7%, respectively. Dynamic 3D DMI scans with oral administration of [6,6'-2 H2 ]-glucose showed similar kinetics of deuterated glucose appearance and disappearance in the liver and kidney. The measured gastric emptying half time was 80 ± 10min, which is in good agreement with scintigraphy measurements. In conclusion, DMI with oral administration of [6,6'-2 H2 ]-glucose enables simultaneous assessment of gastric emptying and liver and kidney glucose uptake and metabolism. When applied in patients with diabetes, this approach may advance our understanding of the interplay between disturbances in liver and kidney glucose uptake and metabolism and gastric emptying, at a detail that cannot be achieved by any other method.

Ultrasonography assessment of gastric emptying for different emulsion microstructures was superior to acetaminophen marker method

Gastric emptying (GE) influences postprandial metabolism, including satiety and is partially mediated by food structure. Tools for routine GE assessment and suitable for a range of food structures in metabolic studies are warranted. This study compared GE results from the acetaminophen absorption (plasma concentration) versus ultrasonography (US, gastric antrum area) methods when 15 healthy men consumed four oil-in-water emulsions differing in lipid physical state and emulsifier acid stability, meaning gastric phase behaviours differed. Plasma acetaminophen was only correlated with antrum measurements for the intragastrically stable emulsion with liquid lipid droplets (P = 0.041, r = -0.69). The US results support the role of colloidal stability in delaying GE and the images showed differences gastric phase behaviours. In contrast, acetaminophen’s solubility confounded the results when the emulsions were susceptible to acidic flocculation. US antrum measurements (but not the acetaminophen results) were also correlated with participant subjective satiety (P < 0.0001), supporting the close mediation of satiety perception by antral distention. Overall, US was superior to the acetaminophen method for assessing GE. It was easily implemented, provided visual insights into gastric phase behaviour and predicted subjective satiety responses, allowing us to relate food structure and changes therein during digestion to metabolic response. • Emulsion gastric structure influences emptying, satiety & postprandial metabolism • Gastric ultrasound was implemented to visualize antrum phase behaviour in 15 men • Gastric emptying was also quantified after consuming four oil-in-water emulsions • Ultrasonography was superior to the acetaminophen marker method for emptying • It evidenced gastric structure & correlated with participant satiety ratings

Tolerability, gastric emptying patterns, and symptoms during the Nottingham Test Meal in 330 secondary care non-diabetic dyspeptic patients.

Scintigraphy is used for overall assessment of gastric emptying. Adherence to an international consensus protocol is recommended to ensure quality; however, this has not been widely adopted because preparation of the "egg-beater" meal is inconvenient in clinical practice. In this report, we audit the tolerability and the results of gastric emptying scintigraphy with the 400 ml Tc-99 m-labeled liquid nutrient Nottingham Test Meal (NTM). Results from 330 consecutive adult, non-diabetic patients with dyspeptic symptoms referred for gastric scintigraphy were analyzed. Gastric half-emptying time (T50) and validated measurements of early- and late-phase gastric emptying were acquired. Postprandial sensations of fullness, bloating, heartburn, nausea, and epigastric pain were recorded using 100 mm visual analog scales (VAS) before and 0, 30, and 90 min after NTM ingestion. Results were compared with those previously obtained in healthy subjects. Almost all (98%) of the patients were able to consume the 400 ml NTM. Considering early- and late-phase gastric emptying, frequently observed patterns included normal early- with slow late-phase (25%) and fast early- with slow late-phase emptying (27%). Abnormal score of fullness and/ or dyspeptic symptoms were observed in 88% of dyspeptic patients. Abnormal fullness at T0 (after completed drink ingestion) was associated with slow late phase of gastric emptying, especially in women. Gastric scintigraphy with the NTM is simple to perform and well tolerated. Whether the identified abnormal gastric emptying patterns could predict different treatment outcome in patients with functional dyspepsia is the subject of ongoing prospective studies.

One-hour plasma glucose level after a 75 g oral glucose load and its relationship to gastric emptying in survivors of critical illness and stress hyperglycaemia

Objective: A 1-hour plasma glucose level ≥ 8.6 mmol/L in a 75 g oral glucose tolerance test has been strongly associated with increased morbidity and mortality in outpatients without diabetes. Our primary aim was to evaluate the 1-hour plasma glucose level in a 75 g glucose tolerance test in survivors of critical illness with stress hyperglycaemia at 3 months after intensive care unit (ICU) discharge, with the secondary aims to evaluate the 2-hour plasma glucose level, glycated haemoglobin (HbA1c), and gastric emptying. Design:Post hoc analysis of a single-centre, prospective cohort study. Setting: Single-centre, tertiary referral, mixed medical-surgical ICU. Participants: Consecutively admitted patients aged ≥ 18 years who developed stress hyperglycaemia and survived to hospital discharge were eligible. Interventions: Participants returned at 3 months after ICU discharge and underwent a 75 g oral glucose tolerance test. Main outcome measures: One- and 2-hour post load plasma glucose level, HbA1c, and assessment of gastric emptying via an isotope breath test. Results: Thirty-five patients (12 females; mean age, 58.5 years [SD, 10.5]; mean HbA1c, 37.4 mmol/mol [SD, 7.0]) attended the followup. In 32/35 patients (91%) the 1-hour post load plasma glucose level was ≥ 8.6 mmol/L. There was a positive correlation between the plasma glucose level at 1 hour (r2 = 0.21; P = 0.006), but no correlation between the 2-hour glucose level (r2 = 0.006; P = 0.63) and gastric emptying. Conclusion: Glucose intolerance, when defined as 1-hour glucose level ≥ 8.6 mmol/L following a 75 g oral glucose load, persists at 3 months in most survivors of stress hyperglycaemia and is dependent on the rate of gastric emptying. Longitudinal studies to characterise mechanisms underlying dysglycaemia and progression to diabetes in individuals with stress hyperglycaemia are indicated.

Sleeve Gastrectomy with Pyloroplasty in Wistar Rats: Assessment of Gastric Emptying, Intestinal Transit, and Possible Duodenogastric Alkaline Reflux.

Studies indicate sleeve gastrectomy (SG) as a factor of aggravation or even emergence of symptoms of gastroesophageal reflux disease. Accelerated gastric emptying is described as a mitigating factor. SG may be potentiated by adding a pyloroplasty, although with the potential risk of resulting in duodenogastric alkaline reflux. The objective was to standardize sleeve gastrectomy with pyloroplasty in rats, analyze the complementation in terms of mortality and weight evolution, and conduct assessments on gastric emptying, intestinal transit, and genesis of possible duodenogastric reflux. Ninety-three male Wistar rats were divided into a pilot study (standardization of the surgical technique and the scintigraphic study), and the main study. They were then subdivided into the SHAM group, the sleeve gastrectomy (SG) group, and the sleeve gastrectomy with pyloroplasty (SGP) group. After 3months, the animals were submitted to two scintigraphic experiments and histological analysis of gastric biopsies. The surgical groups (SG and SGP) lost initially more weight than the SHAM group, and the gastric emptying and intestinal transit in the first were more accelerated. However, no difference was found between the SG and SGP groups. Scintigraphic and histological analyses did not reveal statistical differences among the SG and SGP groups regarding gastroesophageal and duodenogastric refluxes. Pyloroplasty did not affect weight reduction or increase duodenogastric reflux, after three postoperative months in this animal model of sleeve gastrectomy.

Measurement of Gastric Emptying Using a 13C-octanoic Acid Breath Test with Wagner-Nelson Analysis and Scintigraphy in Type 2 Diabetes.

Breath tests utilising 13C-labelled substrates for the assessment of gastric emptying have been applied widely. Wagner-Nelson analysis is a pharmacokinetic model that can be utilised to generate a gastric emptying curve from the % 13CO2 measured in breath samples. We compared Wagner-Nelson analysis with (i) scintigraphy and (ii) conventional breath test modelling to quantify gastric emptying in type 2 diabetes. Thirteen patients (age 68.1±1.5 years, body mass index 31.0±0.9 kg/m2, HbA1c 6.3±0.2%) consumed a mashed potato meal comprising 65 g powdered potato, 20 g glucose, 250 ml water, an egg yolk labelled with 100 μL 13C-octanoic acid and 20MBq 99mTc-calcium phytate. Scintigraphic data were acquired and breath samples collected for 4 hours after the meal. Gastric emptying curves were derived based on each technique; the 50% emptying time and intragastric retention at 60 min were also calculated. With Wagner-Nelson analysis, a Kel=0.60 (the elimination constant) best approximated the scintigraphic gastric emptying curve. There was a relationship between the T50 calculated with scintigraphy and by both Wagner-Nelson Kel=0.60 (r2=0.45, P<0.05) and conventional analysis (r2=0.44, P<0.05). There was no significant difference in the 50% gastric emptying time for scintigraphy (68.5±4.8 min) and Wagner-Nelson Kel=0.60 (71.3±4.5 min), however, the 50% gastric emptying time calculated by conventional analysis was much greater at 164.7±6.0 min (P<0.001). In type 2 diabetes, gastric emptying of a mashed potato meal measured using a 13C-octanoic acid breath test analysed with Wagner-Nelson Kel=0.60 closely reflects measurements obtained with scintigraphy, whereas, in absolute terms, the conventional breath test analysis does not.

Comparison of gastric motility in patients of type 2 diabetes mellitus with various degrees of glycemic control.

ABSTRACTThe aim of this study was to evaluate the effect of glycemic control as estimated by glycated hemoglobin A1c (HbA1c) on gastric emptying in patients with type 2 diabetes mellitus (DM) using gastric emptying scintigraphy (GES). This was a cross-sectional study conducted at a tertiary health care center in Northern India. The study included 44 patients who underwent GES using a radiolabeled solid Idli meal containing 1 mCi of Tc-99 m Sulfur Colloid. Patients were divided into three groups based on glycemic control as Group A, B, and C with HbA1c <7%, 7%–9%, and >9%. Statistical analysis was performed using the IBM® SPSS® Statistics Version 23.0 The comparison of proportions was done using the Chi-square test and Fisher's exact test. Means were compared using the independent t-test and one-way analysis of variance. P < 0.05 was considered statistically significant. No statistically significant correlation was found between delayed gastric emptying and glycemic control (P = 0.09), gender (P = 0.228), dietary patterns (P = 0.91), symptoms of gastroparesis (P = 0.06), body mass index (BMI) (P = 0.267), and duration of type 2 DM (P = 0.565). No statistically significant association was also found between glycemic control and time taken for half gastric emptying (t1/2) (P = 0.225). Scintigraphy using Tc-99m Sulfur Colloid radiolabeled Idli meal can be effectively used for the assessment of gastric emptying. There is no significant correlation of delayed gastric emptying with glycemic control, gender, BMI, type of diet, and duration of diabetes mellitus.

Yeokwisan, a Standardized Herbal Formula, Enhances Gastric Emptying via Modulation of the Ghrelin Pathway in a Loperamide-induced Functional Dyspepsia Mouse Model.

Background: Yeokwisan, a standardized herbal formula, has exhibited clinical benefit for patients suffering from refractory functional dyspepsia (FD) in Korea since 2016. However, data about the mechanism of action of this formula are yet not available.Aim of the study: To evaluate and explore the effects of Yeokwisan on gastric emptying, a major symptom of functional dyspepsia, and its underlying mechanisms of action using a mouse model.Materials and methods: BALB/C mice were pretreated with Yeokwisan (100, 200, and 400 mg/kg, po) or mosapride (3 mg/kg, po) for 5 days and then treated with loperamide (10 mg/kg, ip) after 20 h of fasting. A solution of 0.05% phenol red (500 μL) or diet of 5% charcoal (200 μL) was orally administered, followed by assessment of gastric emptying or intestinal transit. Plasma acyl-ghrelin (ELISA), C-kit (immunofluorescence and western blotting), nNOS (western blotting) and gastric contraction- and ghrelin-related gene/protein expression levels were examined in stomach and small intestine tissues.Results: Loperamide injection substantially delayed gastric emptying, while Yeokwisan pretreatment (especially 200 and 400 mg/kg Yeokwisan) significantly attenuated this peristaltic dysfunction, as evidenced by the quantity of phenol red retained in the stomach (p < 0.05 or 0.01) and stomach weight (p < 0.05 or 0.01). The levels of plasma acyl-ghrelin and expression of gastric ghrelin-related genes, such as growth hormone secretagogue receptor (GHSR), ghrelin-O-acyltransferase (GOAT), adrenergic receptor β1 (ADRB1) and somatostatin receptor (SSTR), were significantly normalized (p < 0.05 or 0.01) by Yeokwisan (400 mg/kg). Yeokwisan (400 mg/kg) significantly tempered the loperamide-induced alterations in the c-kit and nNOS levels (p < 0.01) as well as the expression of contraction- and ghrelin-related genes, such as 5-HT4 receptor (5-HT4R), anoctamin-1 (ANO1), ryanodine receptor 3 (RYR3) and smooth muscle myosin light chain kinase (smMLCK), in the stomach, but not in the small intestine.Conclusion: The present results showed the clinical relevance of Yeokwisan, in treating FD, especially in promoting gastric emptying but not small intestinal transit. The main mechanisms corresponding to these effects may involve the modulation of the ghrelin pathway and activation of interstitial cells of Cajal in stomach tissue.

Automatic assessment of human gastric motility and emptying from dynamic 3D magnetic resonance imaging.

Time-sequenced magnetic resonance imaging (MRI) of the stomach is an emerging technique for non-invasive assessment of gastric emptying and motility. However, an automated and systematic image processing pipeline for analyzing dynamic 3D (ie, 4D) gastric MRI data has not been established. This study uses an MRI protocol for imaging the stomach with high spatiotemporal resolution and provides a pipeline for assessing gastric emptying and motility. Diet contrast-enhanced MRI images were acquired from seventeen healthy humans after they consumed a naturalistic contrast meal. An automated image processing pipeline was developed to correct for respiratory motion, to segment and compartmentalize the lumen-enhanced stomach, to quantify total gastric and compartmental emptying, and to compute and visualize gastric motility on the luminal surface of the stomach. The gastric segmentation reached an accuracy of 91.10±0.43% with the Type-I error and Type-II error being 0.11±0.01% and 0.22±0.01%, respectively. Gastric volume decreased 34.64±2.8% over 1h where the emptying followed a linear-exponential pattern. The gastric motility showed peristaltic patterns with a median=4 wave fronts (range 3-6) and a mean frequency of 3.09±0.07 cycles per minute. Further, the contractile amplitude was stronger in the antrum than in the corpus (antrum vs. corpus: 5.18±0.24 vs. 3.30±0.16mm; p<0.001). Our analysis pipeline can process dynamic 3D MRI images and produce personalized profiles of gastric motility and emptying. It will facilitate the application of MRI for monitoring gastric dynamics in research and clinical settings.

Effect of Extra Virgin Olive Oil and Butter on Endothelial Function in Type 1 Diabetes.

Post-prandial hyperglycemia can be relevant in developing early manifestations of atherosclerosis. EVOO (Extra Virgin Olive Oil), rich in saturated fatty acids and commonly used in the Mediterranean diet, seems to control post-prandial hyperglycemia better than butter. Subjects with type 1 diabetes are at higher risk of developing cardiovascular disease and show endothelial dysfunction, an early manifestation of atherosclerosis in the first years of the disease. Our study aims to evaluate whether EVOO and butter influence endothelial function in subjects with type 1 diabetes when added to a single high glycemic index (HGI) meal. In this exploratory cross-over study, 10 subjects with type 1 diabetes and 6 healthy subjects were scheduled to receive two types of HGI meals: one enriched with EVOO and one with butter. Before and after each test meal at different time points, all subjects underwent the evaluation of endothelial function by flow-mediated dilation technique, glucose and lipids measurements, and gastric emptying assessment by ultrasound. Flow-mediated dilation significantly increased after EVOO-enriched meal compared with butter in subjects with type 1 diabetes (two-way-repeated measurements ANOVA, p = 0.007). In patients with type 1 diabetes, the add-on of EVOO to HGI meal improves vascular function compared to butter, which has detrimental effects.

Ultrasound Assessment of Gastric Emptying in Premature Infants Treated With Non-Invasive Ventilatory Support.

Nasal continuous positive airway pressure (CPAP) introduces positive pressure of air into both the trachea and stomach, which may affect gastric emptying. The rate of gastric emptying can be estimated by ultrasound (US) in neonates by two validated techniques: "antral cross-sectional area" (ACSA, two-dimensional estimate of the surface area at the gastric antrum), and "spheroid gastric volume" (spheroid, three-dimensional estimate of the stomach volume). To compare gastric emptying rates in neonates on machine-derived nasal CPAP (MD-nCPAP, Avea and RAM cannula) with those on bubble CPAP (bCPAP, Fisher Paykel and Babi.Plus nasal prongs). Ultrasound measurements of the amount of the milk in the stomach were performed before feeding and at 1, 2, and 3 hours after the start of feeding, using both the ACSA and spheroid methods. Rates of gastric emptying were calculated during the "early" (1-2 hours) and "late" (2-3 hours) phases after feeding. We recruited 32 infants (25-34 weeks gestational age, full enteral tube feedings, on nasal CPAP). Seventeen infants were treated with MD-nCPAP (median birth weight 1015 g [interquartile range (IQR): 870-1300], gestational age 28 weeks [IQR: 27-29], postnatal age 20 days [IQR: 14-28]), whereas 15 infants were treated with bCPAP (median birth weight 960 g [IQR: 855-1070], gestational age 27 weeks [IQR: 26-28], postnatal age 17 days [IQR: 15-25]). Gastric emptying rates (% emptied/min) were significantly faster in the "early" compared to the "late" phase for all infants. There were no significant differences in the rates of gastric emptying (either "early" or "late") or volumes of gastric residuals between infants receiving MD-nCPAP or bCPAP, measured by either method. Although no feeding intolerance was seen in either group, the volumes of residual gastric contents measured by both methods were higher than the volumes traditionally considered abnormal when obtained by gastric tube aspiration. Gastric emptying is faster during the "early" compared to the "late" phase. Gastric emptying rates are not different in infants receiving MD-nCPAP versus bCPAP. The presence of large residual gastric contents in infants who are tolerating feedings challenges the value of traditional gastric aspiration for the assessment of feeding tolerance in infants.

An Ultrasound Assessment of Gastric Emptying Following Tea With Milk in Pregnancy: A Randomized Controlled Trial

(Eur J Anaesthesiol. 2020;37:303–308) Fasting guidelines from the American Society of Anesthesiologists (ASA) and European Society of Anaesthesiologists (ESA) recommend that clear fluids, including tea without milk, can be ingested up to 2 hours before general or regional anesthesia. Milk is considered to have the same gastric emptying time as solid food and requires a fasting period [nil per os (NPO) time] of 6 hours. While both guidelines suggest that a small amount of milk may be added to clear fluids without impacting NPO times, there is little evidence to support this guidance. The aim of this study was to compare gastric emptying of tea with milk versus water in pregnant women.

68Ga-NOTA PET imaging for gastric emptying assessment in mice

BackgroundPositron emission tomography (PET) has the potential for visualization and quantification of gastric emptying (GE). The traditional Chinese medicine (TCM) has been recognized promising for constipation. This study aimed to establish a PET imaging method for noninvasive GE measurement and to evaluate the efficacy of a TCM on delayed GE caused by constipation using PET imaging.Methods[68Ga]Ga-NOTA was synthesized as the tracer and sesame paste with different viscosity were selected as test meals. The dynamic PET scans were performed after [68Ga]Ga-NOTA mixed with test meals were administered to normal mice. Two methods were utilized for the quantification of PET imaging. A constipation mouse model was treated with maren chengqi decoction (MCD), and the established PET imaging scans were performed after the treatment.Results[68Ga]Ga-NOTA was synthesized within 20 min, and its radiochemical purity was > 95%. PET images showed the dynamic process of GE. %ID/g, volume, and total activity correlated well with each other. Among which, the half of GE time derived from %ID/g for 4 test meals were 3.92 ± 0.87 min, 13.1 ± 1.25 min, 17.8 ± 1.31 min, and 59.7 ± 3.11 min, respectively. Constipation mice treated with MCD showed improved body weight and fecal conditions as well as ameliorated GE measured by [68Ga]Ga-NOTA PET.ConclusionsA PET imaging method for noninvasive GE measurement was established with stable radiotracer, high image quality, and reliable quantification methods. The efficacy of MCD on delayed GE was demonstrated using PET.

Functional Dyspepsia and Gastroparesis in Tertiary Care are Interchangeable Syndromes With Common Clinical and Pathologic Features

The aim of this study was to clarify the pathophysiology of functional dyspepsia (FD), a highly prevalent gastrointestinal syndrome, and its relationship with the better-understood syndrome of gastroparesis. Adult patients with chronic upper gastrointestinal symptoms were followed up prospectively for 48 weeks in multi-center registry studies. Patients were classified as having gastroparesis if gastric emptying was delayed; if not, they were labeled as having FD if they met Rome III criteria. Study analysis was conducted using analysis of covariance and regression models. Of 944 patients enrolled during a 12-year period, 720 (76%) were in the gastroparesis group and 224 (24%) in the FD group. Baseline clinical characteristics and severity of upper gastrointestinal symptoms were highly similar. The 48-week clinical outcome was also similar but at this time 42% of patients with an initial diagnosis of gastroparesis were reclassified as FD based on gastric-emptying results at this time point; conversely, 37% of patients with FD were reclassified as having gastroparesis. Change in either direction was not associated with any difference in symptom severity changes. Full-thickness biopsies of the stomach showed loss of interstitial cells of Cajal and CD206+ macrophages in both groups compared with obese controls. A year after initial classification, patients with FD and gastroparesis, as seen in tertiary referral centers at least, are not distinguishable based on clinical and pathologic features or based on assessment of gastric emptying. Gastric-emptying results are labile and do not reliably capture the pathophysiology of clinical symptoms in either condition. FD and gastroparesis are unified by characteristic pathologic features and should be considered as part of the same spectrum of truly "organic" gastric neuromuscular disorders. CLINICALTRIALS. NCT00398801, NCT01696747.

263-OR: Counterregulatory Responses to Hypoglycemia in Totally Pancreatectomized Patients

We have previously shown that totally pancreatectomized (PX) patients secrete substantial amounts of glucagon (most likely from enteroendocrine cells) during an oral glucose tolerance test (OGTT) whereas these patients suppress circulating glucagon concentrations during intravenous glucose infusions. Here, we investigated the effect of insulin-induced hypoglycemia on extrapancreatic glucagon secretion and other counterregulatory factors in PX patients and in healthy controls (CTRLs). On two separate days, 12 PX patients (age 65.5±5.5 [mean±SD] years; BMI: 23.8±3.6 kg/m2) and 12 matched, healthy CTRLs (age 64.8±6.5 years; BMI: 24.5±2.9 kg/m2) underwent 1) a 50-g OGTT with 1.5 g acetaminophen (for assessment of gastric emptying) and 2) an insulin-induced hypoglycemic clamp followed by a 30-minute recovery period and a subsequent 50-g OGTT with acetaminophen. Blood was intermittently sampled throughout both experimental days. Plasma glucagon responses to OGTT (as assessed by baseline-subtracted area under curve) were greater in PX patients compared to CTRLs (386±150 vs. -340±50 min×pmol/l [mean±SEM], P=0.0001). During the hypoglycemic clamp, PX patients did not increase plasma glucagon concentrations and, thus, glucagon responses to hypoglycemia were higher in CTRLs (903±104 vs. -21±16 min×pmol/l, P&amp;lt;0.001). Hypoglycemia-induced responses of catecholamines, growth hormone and cortisol were similar in the two groups. Gastric emptying was unaffected by hypoglycemia in CTRLs but was decelerated by hypoglycemia in PX patients. We conclude that 1) insulin-induced hypoglycemia, which powerfully stimulates glucagon secretion in CTRLs, does not stimulate extrapancreatic glucagon secretion in PX patients; 2) counterregulatory responses of catecholamines, growth hormone and cortisol were intact in PX patients, but hypoglycemia decelerated gastric emptying in these patients. This provides mechanistic insight into the high risk of hypoglycemia in PX patients. Disclosure M. Baekdal: None. A.B. Lund: Speaker’s Bureau; Self; AstraZeneca, Novo Nordisk A/S, Sanofi. M. Baldassarre: None. J.I. Egholk: None. K. Rose: None. C. Hansen: None. J.H. Storkholm: None. M.B. Christensen: None. B. Hartmann: None. J. Faber: None. J.J. Holst: Advisory Panel; Self; AstraZeneca, Merck Sharp &amp; Dohme Corp., Novo Nordisk A/S, Zealand Pharma A/S. Other Relationship; Spouse/Partner; Antag Therapeutics. T. Vilsbøll: Advisory Panel; Self; AstraZeneca, Mundipharma International, Novo Nordisk A/S, Sun Pharmaceutical Industries Ltd. Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Lilly Diabetes, Medscape, Merck Sharp &amp; Dohme Corp., Sanofi. F.K. Knop: Advisory Panel; Self; AstraZeneca, Merck Sharp &amp; Dohme Corp., Mundipharma International, Novo Nordisk A/S, Sanofi. Consultant; Self; Carmot Therapeutics, Inc., Eli Lilly and Company, Novo Nordisk A/S. Research Support; Self; AstraZeneca, Gubra, Novo Nordisk A/S, Sanofi, Zealand Pharma A/S. Speaker’s Bureau; Self; AstraZeneca, Lupin Pharmaceuticals, Inc., Merck Sharp &amp; Dohme Corp., Norgine B.V., Novo Nordisk A/S.

Effects of Sustained Treatment With Lixisenatide on Gastric Emptying and Postprandial Glucose Metabolism in Type 2 Diabetes: A Randomized Controlled Trial.

Tachyphylaxis for slowing of gastric emptying is seen with continuous exposure to glucagon-like peptide 1 (GLP-1). We therefore aimed to establish whether prolonged use of a "short-acting" GLP-1 receptor agonist, lixisenatide, achieves sustained slowing of gastric emptying and reduction in postprandial glycemia. A total of 30 patients with metformin-treated type 2 diabetes underwent assessment of gastric emptying (scintigraphy) and glucose metabolism (dual tracer technique) after a 75-g glucose drink, before and after 8 weeks' treatment with lixisenatide (20 μg subcutaneously daily) or placebo, in a double-blind randomized parallel design. Gastric retention of the glucose drink was markedly increased after lixisenatide versus placebo (ratio of adjusted geometric means for area under the curve [AUC] over 240 min of 2.19 [95% CI 1.82, 2.64], P < 0.001), associated with substantial reductions in the rate of systemic appearance of oral glucose (P < 0.001) and incremental AUC for blood glucose (P < 0.001). Lixisenatide suppressed both glucagon (P = 0.003) and insulin (P = 0.032), but not endogenous glucose production, over 120 min after oral glucose intake. Postprandial glucose lowering over 240 min was strongly related to the magnitude of slowing of gastric emptying by lixisenatide (r = -0.74, P = 0.002) and to the baseline rate of emptying (r = 0.52, P = 0.048) but unrelated to β-cell function (assessed by β-cell glucose sensitivity). Eight weeks' treatment with lixisenatide is associated with sustained slowing of gastric emptying and marked reductions in postprandial glycemia and appearance of ingested glucose. Short-acting GLP-1 receptor agonists therefore potentially represent an effective long-term therapy for specifically targeting postprandial glucose excursions.

Assessment of Gastric Emptying of Maltodextrin, Coffee With Milk, and Orange Juice During Labour at Term Using Point of Care Ultrasound: A Noninferiority Randomized Clinical Trial

(Anaesthesia. 2019;74:856–861) Although patients have commonly been advised to fast for 8 hours before any surgery, some research has shown benefits associated with shorter fasting periods. Pregnant women have generally been considered to have a “full stomach” due to delayed gastric emptying and reduced lower esophageal sphincter tone. However, recent studies have shown normal gastric emptying in nonlaboring parturients after drinking water. Studies in nonpregnant volunteers have found that milk and other drinks with similar caloric content are cleared from the stomach at similar rates. This noninferiority, parallel group study was undertaken to compare gastric emptying rates in laboring women for maltodextrin, coffee with milk, and pulp-free orange juice.