Simultaneous measurement of gastric emptying of a solid meal by ultrasound and by scintigraphy

Chronic nausea and vomiting: a diagnostic approach

INTRODUCTION

Chronic nausea and vomiting (CNV) are commonly encountered symptoms in medical practice. CNV is the presenting symptom in a variety of gastrointestinal and non-gastrointestinal disorders. However, in a significant percentage of patients without an obvious underlying cause, CNV poses a significant diagnostic challenge to the evaluating physician.

AREAS COVERED

A comprehensive clinical history and physical examination form the foundation for further diagnostic work-up. In the present review, we discuss the diagnostic approach to CNV, highlighting the epidemiology, pathophysiology, causes, and modes of evaluation of this condition. Specific investigations, carefully guided by clinical assessment and tailored for each patient, would be more beneficial in diagnosing CNV than empirically performing a blanket of investigations.

EXPERT OPINION

Whilst CNV remains a historically challenging diagnostic and therapeutic dilemma, research into this topic is limited. Hence, there is a growing call for more research into diagnostic modalities for CNV. With scientific advancement and further research, it is hoped that easy-to-use, cheap, noninvasive novel diagnostic modalities for CNV will be available soon.

Ultrasound to guide the individual medical decision by evaluating the gastric contents and risk of aspiration: A literature review

Pulmonary aspiration of gastric contents is one of the most terrible complications following general anesthesia. It is important for patients to prevent this complication by obeying the preoperative fasting protocol strictly. At present, it has been reported by many studies that bedside ultrasound, as a non-invasive and convenient method, could be used to evaluate gastric contents qualitatively and quantitatively. With the advantages of reliability, accuracy and repeatability, it can greatly reduce the risk of aspiration and ensure patients' life security. But most of the data were acquired from the healthy volunteers. For the gastrointestinal disorder, the pregnant women, obesity, children, the elderly and diabetes patients, the accuracy and reliability of ultrasound to predict the risk of aspiration remains to be identified by more further studies. For these patients with increasing risk of aspiration, I-AIM (Indication, Acquisition, Interpretation, Medical decision-making) framework plays an important role in ensuring the safety of patients. It is crucial to make appropriate clinical decisions by evaluating the gastric contents with ultrasound.

Evaluation of Gastric Emptying in Cystic Fibrosis Using Bedside Ultrasonography

OBJECTIVES

Although gastric emptying rate (GER) influences incretin response and nutrient absorption, both defective in people with cystic fibrosis (CF), there are few studies in this group, and the circadian rhythm is unknown. We employed an ultrasonographic technique to assess GER in people with CF following liquid and mixed meals and also evaluated the circadian rhythm, compared to normal controls.

METHODS

Thirteen pancreatic-insufficient adults with CF and 10 healthy controls underwent a fasting oral glucose tolerance test (OGTT; liquid meal) and on a second visit underwent a fasting mixed meal test (MMT) thrice on the same day. GER was measured during the OGTT and each MMT using a 3.5-MHz abdominal transducer probe at baseline and 30, 60, 90, and 120 minutes.

RESULTS

Controls had normal GER for both OGTT and MMT. Compared to controls, people with CF had delayed GER₆₀ for OGTT (mean 46%), which increased with time (P = .001), and also delayed GER₉₀ for MMT in the morning (mean 56%), afternoon (58%), and evening (59%). The GER in the control group was better at all time points throughout the day compared to patients with CF.

CONCLUSIONS

This is the first study to use ultrasonography, an inexpensive bedside technique, to assess GER in adults with CF. For the first time, we have shown that adults with CF have delayed GER for both liquid and mixed meals, and this delay continues throughout the day.

Ultrasound dynamics of gastric content volumes after the ingestion of coconut water or a meat sandwich. A randomized controlled crossover study in healthy volunteers

Background

Adequate preoperative fasting is critical in preventing pulmonary aspiration of gastric content. We proposed to study the sonographic gastric content dynamics after the ingestion of liquid or solid food in healthy volunteers and confront it with current guidelines for preoperative fasting times.

Methods

We performed a prospective, crossover, evaluator-blinded study involving 17 healthy volunteers of both sexes. Each participant fasted for 10 h and was subjected to a baseline gastric ultrasound, intake of 400 mL of coconut water or a 145 g, 355 kcal meat sandwich, and sonographic gastric evaluations after 10 min and every hour until the stomach was completely empty.

Results

At baseline, all subjects had an empty stomach. At 10 min, gastric content [mean + standard deviation (SD)] was 240.4 + 69.3 and 248.2 + 119.2 mL for liquid and solid foods, respectively (p > 0.05). Mean + SD gastric emptying times were 2.5 + 0.7 and 4.5 + 0.9 h for liquid and solid foods, respectively (p < 0.001). For the drink, the stomach was completely empty in 59% and 100% of the subjects after two and four hours, and for the sandwich, 65% and 100% of the subjects after four and seven hours, respectively.

Conclusions

Sonographic gastric dynamics for coconut water and a meat sandwich resulted in complete gastric emptying times higher and lower, respectively, than those suggested by current guidelines for preoperative fasting.

[Ultrasound dynamics of gastric content volumes after the ingestion of coconut water or a meat sandwich. A randomized controlled crossover study in healthy volunteers]

BACKGROUND

Adequate preoperative fasting is critical in preventing pulmonary aspiration of gastric content. We proposed to study the sonographic gastric content dynamics after the ingestion of liquid or solid food in healthy volunteers and confront it with current guidelines for preoperative fasting times.

METHODS

We performed a prospective, crossover, evaluator-blinded study involving 17 healthy volunteers of both sexes. Each participant fasted for 10h and was subjected to a baseline gastric ultrasound, intake of 400mL of coconut water or a 145g, 355kcal meat sandwich, and sonographic gastric evaluations after 10min and every hour until the stomach was completely empty.

RESULTS

At baseline, all subjects had an empty stomach. At 10min, gastric content [mean + standard deviation (SD)] was 240.4 + 69.3 and 248.2 + 119.2mL for liquid and solid foods, respectively (p>0.05). Mean + SD gastric emptying times were 2.5 + 0.7 and 4.5 + 0.9h for liquid and solid foods, respectively (p<0.001). For the drink, the stomach was completely empty in 59% and 100% of the subjects after two and four hours, and for the sandwich, 65% and 100% of the subjects after four and seven hours, respectively.

CONCLUSIONS

Sonographic gastric dynamics for coconut water and a meat sandwich resulted in complete gastric emptying times higher and lower, respectively, than those suggested by current guidelines for preoperative fasting.

Preoperative Assessment of Ultrasonographic Measurement of Antral Area for Gastric Content

BACKGROUND Pulmonary aspiration of the gastric contents is a serious perioperative complication. The aim of this study was to evaluate the efficacy of portable ultrasonography in the preoperative evaluation of the gastric contents of patients. The secondary aim was to examine the relationship between gastric antrum cross-sectional area and age and body mass index (BMI). MATERIAL AND METHODS This single-center, prospective, cross-sectional study included 120 patients who underwent surgery. Measurements the gastric antral cross-sectional areas and quantitative and qualitative measurements of the stomach were taken by ultrasonography guidance in all patients. RESULTS With the patient in a supine position, the mean gastric antrum cross-sectional area was found to be 3.4±2.43 cm² (range, 0.79-17.3 cm²). As the number of hours of fasting increased, the gastric antral cross-sectional area statistically significantly decreased (P<0.05). Increased age and BMI values were determined to increase the gastric antrum cross-sectional area in a linear correlation; r=0.209, P<0.05 and r=0.252, P=0.05, respectively. It was determined that 20.8% of the patients exceeded the high-risk stomach antral cutoff cross-sectional area that was defined as 340 mm2 in patients fasting for at least 8 hours. CONCLUSIONS It was determined that bedside ultrasonography is a useful, non-invasive tool in the determination of gastric content and volume. A significant proportion of surgical patients may not present with an empty stomach despite the recommended fasting protocols.

Roux-en-Y duodenojejunostomy improves gastric emptying in experimental obstruction of the distal duodenum

Introduction

We undertook a comparative survey of gastric emptying (GE) kinetics after two variants of bypass surgery for upper bowel obstruction.

Material & methods

In 10 dogs with experimental upper bowel obstruction, five were randomized to obtain gastrojejunal anastomosis (GA), and the other five received Roux-en-Y duodenojejunal anastomosis (DA). Duplicate scintigraphic measurements of GE of a solid meal were accomplished in every animal before surgery and during the early (2–3 weeks), medium (3 months), and late (6 months) post-operative period. The GE curves were fitted with a power-exponential function to derive the GE half time T½, and the curve shape parameter S.

Results

Early after surgery T½ slightly decreased by -18±21 min in the DA group and lengthened by 91±37 min in the GA group (p = 0.042). In both groups an increase in the S parameter was found then. In either group T½ gradually declined towards the basal value during the medium and late post-operative period. On the other hand, net differences relative to the basal situation in the S values appeared to be positive in the GA group (0.32±0.11 at 3 months; 0.64±0.19 at six months), and negative in the DA group (-0.30±0.09 at 3 months; -0.01±0.20 at six months). Hence a statistically significant contrast was found between those differences: p = 0.0022 at 3 months, and p = 0.045 at six months after the surgery.

Conclusion

Roux-en-Y duodenojejunal anastomosis appears to be superior to the classical gastrojejunal anastomosis while restoring patency of the gastrointestinal passage in the case of upper bowel obstruction.

Normal Values and Clinical Use of Bedside Sonographic Assessment of Postoperative Gastric Emptying: A Prospective Cohort Study

BACKGROUND

GI dysfunction is common after abdominal surgery. However, assessment and diagnosis currently lack objective measurement.

OBJECTIVE

The purpose of this study was to evaluate the feasibility and clinical use of bedside sonographic assessment of gastric emptying by measuring the time to complete emptying of a standard volume of ingested water in patients after colorectal surgery.

DESIGN

This was a prospective cohort study.

SETTINGS

The study was conducted at a single tertiary institution in Sydney.

PATIENTS

Healthy volunteers (n = 30) were studied to establish a reference range. Gastric emptying was then measured in patients (n = 39) before and after colorectal surgery.

INTERVENTION

Assessment of gastric emptying was performed on days 1 to 4 by measuring antral cross-sectional area every 10 minutes after ingestion of 250 mL of water.

MAIN OUTCOME MEASURES

The time to complete emptying of water was used as a surrogate measure of gastric emptying. Information concerning postoperative outcomes, GI symptoms, and recovery was also recorded.

RESULTS

The median time to complete emptying of water for healthy volunteers was 20 minutes (range, 10-40 minutes). The study protocol was completed in 30 of 39 patients. The time to complete emptying of water on day 2 had the best discriminatory power to identify patients with ileus (sensitivity, 85.71%; specificity, 82.61%). Gastric emptying was normal in 20 of 30 (67%) patients, with only 1 case of ileus (false negative). These patients had less nausea (p = 0.0003), earlier intake of solid diet (p = 0.001), and shorter hospital stay (p = 0.040) compared with patients with abnormal gastric emptying.

LIMITATIONS

Ultrasound is operator dependent with a learning curve.

CONCLUSIONS

Bedside sonographic assessment of gastric emptying is feasible and reliable. Assessment of antral contents with a single ultrasound 40 minutes after ingestion of water enables classification of patients into those with normal and abnormal gastric emptying. When performed on postoperative day 2, it has good sensitivity/specificity for discriminating patients with ileus.

Abdominal migraine in children: association between gastric motility parameters and clinical characteristics

Background

Approximately 0.2–1 % of children suffers from abdominal migraine (AM). Pathophysiology of AM has not been adequately studied. This study evaluated gastric motility in children with AM.

Methods

Seventeen children (6 boys), within an age range of 4–15 years, referred to a tertiary care paediatric unit, North Colombo Teaching Hospital Ragama, Sri Lanka, from 2007 to 2012, were screened. Those fulfilling Rome III criteria for AM were recruited after obtaining parental consent. None had clinical or laboratory evidence of organic disorders. Twenty healthy children (8 boys), with an age range of 4–14 years, were recruited as controls. Liquid gastric emptying rate (GE) and antral motility parameters were assessed using an ultrasound method.

Results

Average GE (41.6 % vs. 66.2 %, in controls), amplitude of antral contractions (A) (57.9 % vs. 89.0 %) and antral motility index (MI) (5.0 vs. 8.3) were lower and fasting antral area (1.8 cm² vs. 0.6 cm²) was higher in children with AM (p < 0.01). No significant difference in the frequency of antral contractions (F) (8.8/3 min vs. 9.3/3 min, p = 0.08) was found between the two groups. Scores obtained for severity of abdominal pain had a negative correlation with A (r = −0.55, p = 0.03). Average duration of abdominal pain episodes correlated with GE (r = −0.58, p = 0.02). Negative correlations were observed between duration of AM and A (r = −0.55), F (r = −0.52), and MI (r = −0.57) (p < 0.05).

Conclusions

GE and antral motility parameters were significantly lower in children with AM. A significant correlation was found between symptoms and gastric motility. These findings suggest a possible role of abnormal gastric motility in the pathogenesis of AM.

Gastric emptying evaluation by ultrasound prior colonoscopy: An easy tool following bowel preparation

AIM: To investigate the gastric emptying after bowel preparation to allow general anaesthesia.

METHODS: A prospective, non-comparative, and non-randomized trial was performed and registered on Eudra CT database (2011-002953-80) and on www.trial.gov (NCT01398098). All patients had a validated indication for colonoscopy and a preparation using sodium phosphate (NaP) tablets. The day of the procedure, patients took 4 tablets with 250 mL of water every 15 min, three times. The gastric volume was estimated every 15 min from computed antral surfaces and weight according to the formula of Perlas et al (Anesthesiology, 2009). Colonoscopy was performed within the 6 h following the last intake.

RESULTS: Thirty patients were prospectively included in the study from November 2011 to May 2012. The maximum volume of the antrum was 212 mL, achieved 15 min after the last intake. 24%, 67% and 92% of subjects had an antral volume below 20 mL at 60, 120 and 150 min, respectively. 81% of patients had a Boston score equal to 2 or 3 in each colonic segment. No adverse events leading to treatment discontinuation were reported.

CONCLUSION: Gastric volume evaluation appeared to be a simple and reliable method for the assessment of gastric emptying. Data allow considering the NaP tablets bowel preparation in the morning of the procedure and confirming that gastric emptying is achieved after two hours, allowing general anaesthesia.

[Contribution of ultrasonography for the preoperative assessment of gastric contents]

The assessment of the risk of pulmonary aspiration of gastric contents may be difficult in the preoperative period, apart from typical circumstances. The development of ultrasonography in anesthesia and critical care has led to consider ultrasonic imaging of gastric contents for preoperative risk assessment of "full" stomach in clinical practice. Ultrasonography of the body of the stomach allows direct visualization of the gastric contents. However, the stomach is often difficult to identify, particularly when it is empty. Moreover, quantitative assessment of gastric volume is delicate, and no standardized method of ultrasonography of the body of the stomach for preoperative assessment of gastric contents was described. On the contrary, ultrasonography of the antral cross-sectional area, which was initially described for the assessment of gastric emptying as an alternative method to repeated measurements of the variations of antropyloric volume after ingestion of a test meal, is easy to perform and is highly reproducible through using the aorta and the left lobe of the liver as internal landmarks. Qualitative assessment of the gastric antrum allows easily diagnosis of a "full" stomach. The measurement of antral area may allow a more accurate estimate of the presence or absence of gastric contents at risk of lung injury in the event of regurgitation and aspiration (gastric volume >0.8 ml/kg and/or with solid particles), defining the "risk" stomach. The use of antral ultrasonography may help the anesthesiologist to assess the risk of pulmonary aspiration according to clinical history of the patient, in order to choose an appropriate strategy minimizing the occurrence of this complication.

Effect of nutritional rehabilitation on gastric motility and somatization in adolescents with anorexia

OBJECTIVE

To examine gastric function, as well as the presence of somatic complaints, anxiety symptoms, and functional gastrointestinal disorders (FGIDs), in adolescents with anorexia nervosa (AN) before and after nutritional rehabilitation.

STUDY DESIGN

Sixteen females with AN and 22 healthy controls with similar demographic profiles were included. Gastric emptying (measured as residual gastric volume) and gastric accommodation (measured as postprandial antral diameter) were assessed with abdominal ultrasonography. Participants completed the Children's Somatization Inventory (CSI), the Screen for Child Anxiety-Related Emotional Disorders, and the Questionnaire on Pediatric Gastrointestinal Symptoms-Rome III version. All testing was repeated 3-4 months later.

RESULTS

Body mass index in the AN group improved over time (P = .012). Fasting gastric parameters were similar in the 2 groups. Maximum postprandial antral diameter was significantly greater in controls compared with the AN group (P = .008). Only adolescents with AN demonstrated a significant increase in maximum postprandial diameter at repeat testing (P = .009). There was no difference in residual gastric volume between the 2 groups. Initial CSI scores were higher in adolescents with AN (P < .0001), including higher scores for nausea and abdominal pain. CSI scores were significantly lower in adolescents with AN (P = .035). Initial scores on the Screen for Child Anxiety-Related Emotional Disorders were significantly higher in adolescents with AN (P = .0005), but did not change over time. Adolescents with AN met significantly more criteria for FGIDs (P = .003).

CONCLUSION

Adolescents with AN have impaired gastric accommodation that improves after nutritional rehabilitation, have significantly more somatic complaints, and meet more criteria for anxiety disorders and FGIDs. After nutritional rehabilitation, somatization improves and FGIDs become less common, but symptoms of anxiety persist.

The role of small intestinal bacterial overgrowth in Parkinson's disease

Parkinson's disease is associated with gastrointestinal motility abnormalities favoring the occurrence of local infections. The aim of this study was to investigate whether small intestinal bacterial overgrowth contributes to the pathophysiology of motor fluctuations. Thirty-three patients and 30 controls underwent glucose, lactulose, and urea breath tests to detect small intestinal bacterial overgrowth and Helicobacter pylori infection. Patients also underwent ultrasonography to evaluate gastric emptying. The clinical status and plasma concentration of levodopa were assessed after an acute drug challenge with a standard dose of levodopa, and motor complications were assessed by Unified Parkinson's Disease Rating Scale-IV and by 1-week diaries of motor conditions. Patients with small intestinal bacterial overgrowth were treated with rifaximin and were clinically and instrumentally reevaluated 1 and 6 months later. The prevalence of small intestinal bacterial overgrowth was significantly higher in patients than in controls (54.5% vs. 20.0%; P = .01), whereas the prevalence of Helicobacter pylori infection was not (33.3% vs. 26.7%). Compared with patients without any infection, the prevalence of unpredictable fluctuations was significantly higher in patients with both infections (8.3% vs. 87.5%; P = .008). Gastric half-emptying time was significantly longer in patients than in healthy controls but did not differ in patients based on their infective status. Compared with patients without isolated small intestinal bacterial overgrowth, patients with isolated small intestinal bacterial overgrowth had longer off time daily and more episodes of delayed-on and no-on. The eradication of small intestinal bacterial overgrowth resulted in improvement in motor fluctuations without affecting the pharmacokinetics of levodopa. The relapse rate of small intestinal bacterial overgrowth at 6 months was 43%. © 2013 Movement Disorder Society.

Laparoscopic anterior hemifundoplication improves key symptoms without impact on GE in children with and children without neurodevelopmental delays

AIM

We investigated the impact of laparoscopic anterior hemifundoplication on gastric emptying (GE) and specific symptoms in children with and children without neurodevelopmental delays gastroesophageal reflux. Scintigraphic and ultrasonographic GE measurements were correlated.

PATIENTS AND METHODS

Twenty-six children (mean age 7 ± 6.1 years), of whom 14 were neurodevelopmentally delayed, were evaluated prospectively before 3 and 6 months after laparoscopic anterior hemifundoplication. All of the patients underwent clinical assessments, interviews, and 24-hour pH monitoring. Key symptoms were evaluated using a 5-point Likert scale. Gastric emptying was assessed by Tc-99m-DTPA-scintigraphy and ultrasonography.

RESULTS

All of the children had significant catch-up growth after fundoplication, which was more pronounced in the neurologically normal children (P < 0.05 vs impaired), in line with a decrease in the use of omeprazol (mean 0.93 ± 0.7 mg · kg(-1) · day(-1) before and 0.06 ± 0.18 mg · kg(-1) · day(-1) at 6 months after operation; P < 0.001). The 24-hour pH monitoring normalized in all of the children, and the mean severity of the key symptoms such as vomiting, choking, and pain was significantly reduced (P < 0.001). Scintigraphic GE parameters, such as the elimination rate/minute, gastric half-emptying time (t1/2), gastric residual activity (RA), and duration of the initial merging time, were not altered significantly by the operation (P > 0.05). Ultrasonographic evaluations confirmed these results [positive correlation with scintigraphy for t1/2 (P = 0.006) and RA (P = 0.01)]. The symptoms evolution and GE were uncorrelated (P > 0.01). There were no significant differences between children with and children without neurodevelopmental delays.

CONCLUSIONS

Laparoscopic anterior hemifundoplication achieves an excellent symptomatic outcome without affecting GE in children with and children without neurodevelopmental delays.

Enterra Therapy: gastric neurostimulator for gastroparesis

Gastroparesis is a chronic disorder of gastric motility characterized by delayed gastric empting in the absence of mechanical obstruction, which can lead to symptoms of nausea, vomiting, bloating, abdominal pain, postprandial fullness and weight loss. Although there are many etiologies, the primary causes are diabetes or are idiopathic. The mainstay of treatment is dietary and drug therapies. However, many patients will continue to suffer intractable symptoms despite these treatments. Gastric neurostimulation with the Enterra Therapy system has been approved for use under the Humanitarian Device Exemption by the US FDA. The device produces pulses of electrical stimulation that are delivered to the stomach continuously. One randomized clinical trial and multiple nonrandomized unblinded clinical trials and case series have documented improvement of symptoms in intractable diabetic and idiopathic gastroparesis. The purpose of this article is to introduce the Enterra Therapy gastric neurostimulator. Gastroparesis and its pathophysiology will be discussed in this clinical context to enhance the understanding of the device and its development. We will analyze the device in detail, its placement and the results of studies evaluating its efficacy.

Effects on the pouch of different digestive tract reconstruction modes assessed by radionuclide scintigraphy

AIM: To determine the effect of three digestive tract reconstruction procedures on pouch function, after radical surgery undertaken because of gastric cancer, as assessed by radionuclide dynamic imaging.

METHODS: As a measure of the reservoir function, with a designed diet containing technetium-99m (^99mTc), the emptying time of the gastric substitute was evaluated using a ^99mTc-labeled solid test meal. Immediately after the meal, the patient was placed in front of a γ camera in a supine position and the radioactivity was measured over the whole abdomen every minute. A frame image was obtained. The emptying sequences were recorded by the microprocessor and then stored on a computer disk. According to a computer processing system, the half-emptying actual curve and the fitting curve of food containing isotope in the detected region were depicted, and the half-emptying actual curves of the three reconstruction procedures were directly compared.

RESULTS: Of the three reconstruction procedures, the half-emptying time of food containing isotope in the Dual Braun type esophagojejunal anastomosis procedure (51.86 ± 6.43 min) was far closer to normal, significantly better than that of the proximal gastrectomy orthotopic reconstruction (30.07 ± 15.77 min, P = 0.002) and P type esophagojejunal anastomosis (27.88 ± 6.07 min, P = 0.001) methods. The half-emptying actual curve and fitting curves for the Dual Braun type esophagojejunal anastomosis were fairly similar while those of the proximal gastrectomy orthotopic reconstruction and P type esophagojejunal anastomosis were obviously separated, which indicated bad food conservation in the reconstructed pouches.

CONCLUSION: Dual Braun type esophagojejunal anastomosis is the most useful of the three procedures for improving food accommodation in patients with a pouch and can retard evacuation of solid food from the reconstructed pouch.

Diabetes mellitus and gastric emptying: questions and issues in clinical practice

It is long known that both type 1 and type 2 diabetes can be associated with changes in gastric emptying; a number of publications have linked diabetes to delayed gastric emptying of variable severity and often with poor relationship to gastrointestinal symptomatology. In contrast, more recent studies have reported accelerated gastric emptying when adjusted for glucose concentration in patients with diabetes, indicating a reciprocal relationship between gastric emptying and ambient glucose concentrations. This review proposes that gastroparesis or gastroparesis diabeticorum, a severe condition characterized by a significant impairment of gastric emptying accompanied by severe nausea, vomiting, and malnutrition, is often overdiagnosed and not well contrasted with delays in gastric emptying. The article offers a clinically relevant definition of gastroparesis that should help differentiate this rare condition from (often asymptomatic) delays in gastric emptying. The fact that delayed gastric emptying can also be observed in non-diabetic individuals under experimental conditions in which hyperglycaemia is artificially induced suggests that a delay in gastric emptying rate when blood glucose concentrations are high is actually an appropriate physiological response to hyperglycaemia, slowing further increases in blood glucose. The article discusses the strengths and weaknesses of various methodologies for assessing gastric emptying, especially with respect to the diabetes population, and reviews newer diabetes therapies that decelerate the rate of gastric emptying. These therapies may be a beneficial tool in managing postprandial hyperglycaemia because they attenuate rapid surges in glucose concentrations by slowing the delivery of meal-derived glucose.

Sonographic assessments of gastrointestinal and biliary functions

Ultrasound has been established as a routine work-up imaging method in abdominal diseases. It assesses the morphology of intra-abdominal organs and depicts the normal and pathological anatomy of the gastrointestinal tract as well as of the biliopancreatic system. Ultrasound is the method of choice for visualisation of motion sequences since it is, in contrast to other imaging methods, a real-time method. The non-invasiveness and the repeatability of the method are important advantages when performing investigations of functional processes. Therefore, ultrasound is most suited for functional studies. Up to now, functional ultrasound and its potential have been undervalued. Functional ultrasound provides a widely available method to increase our understanding of functional processes and motility. The authors review the options of functional ultrasound and discuss its practical relevance.

Pathophysiology and management of gastroparesis

Gastroparesis is characterized by upper gastrointestinal symptoms associated with delayed gastric emptying, without mechanical obstruction. However, symptoms do not correlate well with the magnitude of delay in gastric emptying. Diabetes mellitus and surgery are the most common causes, although more than 30% of cases are idiopathic. Coordination of insulin action with nutrient delivery is important in diabetics, as postprandial blood glucose levels and gastric emptying are interdependent, and gastroparesis probably represents a major cause of poor glycemic control. Scintigraphy is the gold standard for measuring gastric emptying. Current treatment mainly involves the use of prokinetic drugs. Pyloric botulinum toxin injection and gastric electrical stimulation require more evidence from controlled studies before their use can be recommended. Surgical options remain inadequately studied.

Methods for measurement of gastric motility

There is an array of tests available to measure gastric motility. Some tests measure end points, such as gastric emptying, that result from several different functions, whereas other tests are more specific and test only a single parameter, such as contractility. This article reviews the tests most commonly available in practice and research to evaluate in vivo the gastric functions of emptying, accommodation, contractility, and myoelectrical activity. The rationale for testing, the relative strengths and weaknesses of each test, and technical details are summarized. We also briefly indicate the applications and validations of the tests for use in experimental animal studies.

Increasing severity of cardiac autonomic neuropathy is associated with increasing prevalence of nephropathy, retinopathy, and peripheral neuropathy in Turkish type 2 diabetics

BACKGROUND

Cardiac autonomic neuropathy (CAN) is the most frequent and clinically important form of diabetic autonomic neuropathy. CAN is associated with increased frequency of other microvascular complications of diabetes mellitus (DM). In this study, we evaluated the prevalence diabetic nephropathy, retinopathy, and peripheral neuropathy, and measured gastric emptying time and bladder emptying time in type 2 diabetic patients with varying degrees of CAN.

PATIENTS AND METHODS

Fifty-three patients with DM complicated by CAN (30 women and 23 men; mean age, 58.8+/-9.15 years; duration of diabetes, 13.9+/-7.7 years) were included in this study. The patients were grouped according to the degree of CAN as early, definite, and severe CAN.

RESULTS

There were significant differences regarding the prevalence of nephropathy, retinopathy, and peripheral neuropathy diagnosed by EMG among those groups (P<.05). However, there was no significant difference regarding the prevalence of peripheral neuropathy diagnosed by neurological examination (P>.05), and scintigraphic measurements of gastric and bladder emptying time were comparable among the groups (P>.05).

CONCLUSION

The prevalence of other diabetic microvascular complications increase as the severity of CAN increases in patients with type 2 DM. This study emphasizes the need for an early screening for peripheral neuropathy, retinopathy, and nephropathy in type 2 diabetic patients with CAN, especially with severe involvement.

Review article: gastroparesis

BACKGROUND

Gastroparesis is a chronic disorder caused by stomach pump failure and characterized by profound nausea, vomiting and epigastric pain. Most often, the cause is unapparent and of the known associations, diabetes is the most common. Diagnosis is usually made using an isotope-labelled test meal. Treatment is incremental and includes education, dietary support, prokinetic and antiemetic agents. There are novel approaches including gastric neurostimulation.

AIM

To review current concepts of gastric motor function, aetiology, investigation and treatment of gastroparesis.

METHODS

A systematic web-based review of the literature was undertaken using a lexicon of terms associated with gastroparesis.

RESULTS

There are few controlled studies of this condition. Little is known about causation or underlying nerve, muscle or pacemaker pathology. Idiopathic gastroparesis occurs most commonly in women and gastric emptying is often abnormal in diabetes. Isotopic gastric scintigraphy remains the gold standard investigation, but alternative tests are being developed. Treatment is multimodal and includes education, and nutritional support. There are no adequately powered controlled trials to support a particular drug regimen. In intractable gastroparesis, gastric neurostimulation appears to offer benefit.

CONCLUSION

Despite a significant progress in the past decade, further controlled trials are required into the therapeutic options available for treating this intriguing condition.

Gastroparesis associated with gastroesophageal reflux disease and corresponding reflux symptoms may be corrected by radiofrequency ablation of the cardia and esophagogastric junction

BACKGROUND

Reflux is a common medical condition with symptoms ordinarily controlled using drug/medical therapy. However, 20% of patients experience unmanageable symptoms despite twice-daily (BID) proton pump inhibitor (PPI) therapy. Growing clinical evidence shows that delayed gastric emptying (gastroparesis) may be a factor associated with severe reflux, dyspepsia, or both. Gastroparesis, concomitant in 25% of patients with gastroesophageal reflux disease (GERD), has been shown to improve after Nissen fundoplication. Radiofrequency treatment for GERD potentially corrects GERD-associated gastroparesis and resultant PPI BID reflux failures.

METHODS

From July 2000 until July 2004, 227 patients undergoing Stretta for GERD were screened for gastric anomalies. Patients with gastroparesis, documented on a standardized nuclear gastric emptying scans, and patients with heartburn and regurgitation uncontrolled by PPI BID medications underwent radiofrequency ablation of the cardia and esophagogastric junction via the Stretta procedure. The patients had esophagogastroduodenoscopy and/or pH studies, manometry, solid-phase gastric emptying, and electrogastrography and completed standardized heartburn and health-related quality-of-life surveys before treatment, then 6 months afterward. Patients with pyloric obstruction and those taking motility agents were excluded from the study. Gastric emptying scans were repeated 6 months after Stretta. The nuclear radiologist was blinded to the study design.

RESULTS

At baseline, 31 patients were classified as abnormal. At 6 months after the procedure, emptying scores had improved significantly, with the percentage of solid food emptied at 90 min improved from 41% to 66% (p < 0.0001) and at 120 minutes from 55% to 84%. Significant improvements were seen at all intervals. Overall, 23 patients (74%) experienced normalization of gastric emptying, and 4 patients were improved but remained abnormal. Four patients showed no improvement on their gastric emptying scans, with one patient electing to undergo a Nissen procedure. All the patients had a 1-year symptom follow-up assessment, which showed significant improvements in GERD health-related quality of life, dyspepsia, and heartburn scores.

CONCLUSIONS

Radiofrequency treatment has been demonstrated to correct gastroparesis. Patients' symptoms improved significantly. The mechanism of action is unknown but may be related to reduction in transient lower esophageal sphincter relaxations (TLESRs), increased esophagogastric junction barrier, decreased esophageal venting, alteration of the gastric pacemaker function in the region of radiofrequency therapy administration, removal of medications for symptoms, or a combination of all these.

Studies of gastric emptying time in patients with non-ulcer dyspepsia

PURPOSE

To assess the gastric emptying pattern of a standardized solid meal in patients with non-ulcer dyspepsia by using scintigraphic techniques.

METHODS

Results for the half-emptying time for solids (T1/2) and percent clearance of solid meal at 60 min (C60) of patients (n=35) having non-ulcer dyspepsia according to Rome II criteria were compared with age- and sex-matched controls (n=28). Gastric emptying was studied by using egg omelette labelled with Tc tin colloid. Data acquisition was done using two protocols: dynamic acquisition was performed for the first 100 min and then static acquisition was carried out for up to 4 h. T1/2 and C60 were calculated from the computer-generated time-activity curve.

RESULTS

The normal range of T1/2 was 29-88 min (mean+/-2 SD) among the control group. The mean T1/2 of the patient group was 160.1+/-96.1 min (P<0.01). Twelve of 22 male patients and 11 of 13 female patients had prolonged T1/2. The normal range of C60 was 92-28% (mean+/-2 SD) in the control group. The mean C60 of the patient group was 33.1+/-18.5% (P<0.01). Fifteen of 22 male patients and 11 of 13 female patients had shortened C60.

CONCLUSION

Gastric emptying is significantly delayed in both men and women having non-ulcer dyspepsia as the T1/2 is prolonged and the C60 is shortened in a significant number of these patients. Radionuclide tests might offer an objective way of assessing this particular aspect of gastric physiology.

[Diagnostic and therapeutic approach to patients with gastroparesis]

Gastroparesis is a chronic alteration of gastric motility characterized by symptoms suggestive of mechanical obstruction and delayed gastric emptying in the absence of obstruction. Gastroparesis can be idiopathic or attributable to neuropathy or myopathy as in diabetes mellitus and scleroderma or can occur after vagotomy. Diagnosis is based on symptoms (nausea, vomiting, abdominal distension and early satiety), physical examination (capotement) and on complementary investigations, the procedure of choice being isotope gastric emptying tests. Treatment depends on the clinical repercussions. In most patients, gastroparesis can be controlled by prokinetic drugs, dietary measures, exclusion of drugs that alter gastric emptying, and exhaustive control of blood glucose levels. In patients with severe gastroparesis, hospital nutritional measures (intravenous and/or enteral), gastric decompression and intravenous antiemetic and prokinetic agents are required. Aggressive nutritional therapies (parenteral or enteral nasojejunal nutrition), intrapyloric injection of botulinum toxin, implantation of a gastric stimulation device, or gastrectomy should only be used in patients unresponsive to conservative treatment or if there is selective alteration of gastric motility.

Pathophysiology and management of diabetic gastropathy: a guide for endocrinologists

Delayed gastric emptying is frequently observed in patients with long-standing type 1 and type 2 diabetes mellitus, and potentially impacts on upper gastrointestinal symptoms, glycaemic control, nutrition and oral drug absorption. The pathogenesis remains unclear and management strategies are currently suboptimal. Therapeutic strategies focus on accelerating gastric emptying, controlling symptoms and improving glycaemic control. The potential adverse effects of hyperglycaemia on gastric emptying and upper gut symptoms indicate the importance of normalising blood glucose if possible. Nutritional and psychological supports are also important, but often neglected. A number of recent pharmacological and non-pharmacological therapies show promise, including gastric electrical stimulation. As with all chronic illnesses, a multidisciplinary approach to management is recommended, but there are few data regarding long-term outcomes.

The anorexia of aging

Malnutrition in the elderly is one of the greatest threats to health, well-being and autonomy, it is therefore crucial to understand and to contrast the causal factors of inadequate energy intake. This review focuses on the mechanisms of the so-called 'anorexia of aging'. In recent years, it has been shown that elderly subjects have abnormal peripheral signal patterns and alterations in central hypothalamic control relays. Negative feedback from impaired gastric motility, exaggerated long-term adiposity signals (leptin, insulin) and postprandial anorexigenic signals (CCK, PYY) seem to prevail over the central feeding drive. If nutritional strategies of intervention are to be improved, these data need to be taken into account.

Relationship between antral distension and postprandial symptoms in functional dyspepsia

AIM: To investigate in patients with functional dyspepsia (FD) after an every-day meal whether (1) gastrointestinal (GI) and extra-GI symptoms had any relation with the degree of antral volume, (2) the onset of postprandial symptoms was associated with, and may predict, delayed gastric emptying.

METHODS: In 94 symptomatic FD patients, antral volume variations and gastric emptying were assessed with ultrasonography after a 1050 kcal meal. Symptoms were evaluated with a standardized questionnaire. The association of GI and extra-GI symptoms with antral volumes and gastric emptying were estimated with logistic regression analysis.

RESULTS: Forty percent of patients did not report any symptoms after a meal. Compared to the healthy controls, the antrum was more distended in patients throughout the entire observation period and 37 (39.4%) patients had delayed gastric emptying. Only postprandial drowsiness was associated with antral volume variations (AOR = 1.42; P < 0.001) and with delayed gastric emptying (AOR = 3.59; P < 0.03).

CONCLUSION: In FD patients, GI symptoms are neither associated with antral distension nor with gastric emptying. Drowsiness is associated with antral distension and delayed gastric emptying. The onset of drowsiness is preceded by an increment of antral distension and the duration of the symptom appears to be related to the persistence of antral distension.

Relationship between acceleration of gastric emptying and oesophageal acid exposure in patients with endoscopy-negative gastro-oesophageal reflux disease

OBJECTIVE

A delay in gastric emptying has been reported in patients with gastro-oesophageal reflux disease (GORD), but its role in increasing the number of reflux episodes is still debated. The aim of this study was to assess the relationship between acceleration of gastric emptying and gastro-oesophageal reflux in patients with endoscopy-negative GORD and pathological oesophageal acid exposure.

MATERIAL AND METHODS

Twelve patients (7 M, age range 24-65 years) underwent 6-h postprandial (2.1 MJ meal) combined gastric emptying by real-time ultrasonography and intra-oesophageal pH monitoring after cisapride (20 mg b.i.d.) and placebo for 3 days, on two separate occasions at least 7 days apart in double-blind randomized order. Gastric emptying after placebo was also measured in 12 healthy volunteers (7 M, age range 25-54 years).

RESULTS

In the patients' group, the area under the emptying time curve was greater (p<0.01), and half and total emptying times prolonged (p<0.01) compared to the healthy subjects, 115 min (mean)+/-6 (SEM) versus 86+/-6 and 232 min+/-16 versus 160+/-7, respectively. Cisapride accelerated both half- and total gastric emptying (p<0.02): -22 min (mean); -10 to -34 (95% CI) and -48 min; -10 to -85, respectively, decreased both percentage of time at pH < 4 (p<0.01) and number of reflux episodes (p<0.05). However, no relationship was found between changes in gastric emptying and in the reflux variables by linear regression analysis (R2<0.005).

CONCLUSION

The emptying rate of the whole stomach is not a major determinant of gastro-oesophageal reflux.

Prokinetic effect of gut-oriented hypnosis on gastric emptying

BACKGROUND

No data are available on the effect of hypnosis on gastric emptying.

AIM

To determine the effect of a hypnosis session on gastric emptying and dyspeptic symptoms.

METHODS

We studied emptying by ultrasonography and epigastric sensations in 11 healthy subjects and in 15 patients affected by functional dyspepsia under three conditions according to a fixed schedule: (a) basal, (b) after cisapride and (c) during a 90 min hypnotic trance. Eight healthy subjects repeated an emptying study listening to relaxing music. Statistical analysis was performed using the Friedman test or RM-ANOVA.

RESULTS

In dyspeptics, the postprandial increase in the antral area was significantly smaller during the hypnosis trance than under the basal and the cisapride conditions. For the patients gastric emptying was significantly shortened by cisapride, and even more by hypnosis (basal 274 +/- 16.8 min; cisapride 227 +/- 13.2; hypnosis 150 +/- 9.7) whereas for healthy subjects it was shortened only by hypnosis. The repeated study in healthy subjects listening to relaxing music showed no significant difference compared with the basal. Epigastric sensations were improved in dyspeptics by hypnosis, but not by cisapride.

CONCLUSIONS

Gut-oriented hypnosis is effective in shortening gastric emptying both in dyspeptic and in healthy subjects.

Colonic fermentation of indigestible carbohydrates contributes to the second-meal effect

BACKGROUND

Low postprandial blood glucose is associated with low risk of metabolic diseases. A meal's ability to diminish the glucose response to carbohydrates eaten during the following meal is known as the "second-meal effect" (SME). The reduced glycemia elicited by low-glycemic-index (LGI) foods consumed during the first meal has been suggested as the main mechanism for SME. However, LGI foods often increase colonic fermentation because of the presence of fiber and resistant starch.

OBJECTIVE

The objective was to study the SME of greater fermentation of high-glycemic-index (HGI) and LGI carbohydrates eaten during a previous meal.

DESIGN

Ten healthy volunteers ate 3 breakfast test meals consisting of sponge cakes made with rapidly digestible, nonfermentable amylopectin starch plus cellulose (HGI meal), amylopectin starch plus the fermentable disaccharide lactulose (HGI-Lac meal), or slowly digestible, partly fermentable amylose starch plus cellulose (LGI meal). Five hours later, subjects were fed the same standard lunch containing 93 g available carbohydrates. Blood was collected for measurement of glucose, insulin, and nonesterified fatty acids (NEFAs). Breath hydrogen was measured as a marker of colonic fermentation. Postlunch gastric emptying was measured by using ultrasonography.

RESULTS

Both the HGI-Lac and LGI meals improved glucose tolerance at lunch. In the case of the HGI-Lac meal, this effect was concomitant with low NEFA concentrations and delayed gastric emptying.

CONCLUSION

Fermentable carbohydrates, independent of their effect on a food's glycemic index, have the potential to regulate postprandial responses to a second meal by reducing NEFA competition for glucose disposal and, to a minor extent, by affecting intestinal motility.

Apresentação da técnica de estudo do tempo de esvaziamento gástrico por meio da ultra-sonografia

OBJETIVO: Descrever a técnica de avaliação do esvaziamento gástrico em crianças. MATERIAIS E MÉTODOS: Foram estudadas 14 crianças voluntárias saudáveis, com idades de 2 a 11 anos. As crianças ingeriram leite modificado, na proporção de 200 ml/m² de superfície corporal. A área do antro gástrico foi medida em todos os pacientes no tempo zero, antes da ingestão do meio de contraste, e aos 60, 90, 120 e 150 minutos após a ingestão do meio de contraste. RESULTADOS: A dieta foi bem tolerada pelos pacientes. Foi observado que em 150 minutos após a ingestão do alimento, 85% dos pacientes apresentaram-se com esvaziamento gástrico total. CONCLUSÃO: A ultra-sonografia é método seguro e barato, sendo uma alternativa para o estudo do esvaziamento gástrico.

Delayed Postprandial Gastric Emptying and Impaired Gallbladder Contraction Together With Elevated Cholecystokinin and Peptide YY Serum Levels Sustain Satiety and Inhibit Hunger in Healthy Elderly Persons

BACKGROUND

Altered gastric and cholecystic motility are risk factors for malnutrition in elderly persons, mainly through impaired satiety-appetite rhythm. Contrasting data have been published about this topic. The aim of this study was to evaluate, in healthy elderly participant, postprandial gastric and cholecystic emptying in relation to serum CCK (cholecystokinin) and PYY (peptide YY), as well as satiety and hunger sensations.

METHODS

We studied 10 community-dwelling elderly persons, (77 +/- 3 years old) and 9 younger adult persons (32 +/- 8 years old). Using ultrasonography, we measured gastric antrum area and cholecystic volume in fasting condition and after an 800-kcal mixed meal. Time for gastric and cholecystic emptying, and percentage of cholecystic emptying were calculated. Satiety and hunger were evaluated every 30 minutes using visual analogue scales. CCK and PYY serum levels were assayed 30 minutes before and at times 0, 30, 60, 120, and 240 minutes after the meal.

RESULTS

Elderly participants showed a longer gastric emptying time compared to younger participants (448 +/- 104 vs 306 +/- 57 minutes, p <.002). Postprandial cholecystic emptying was significantly reduced in the older group (maximum contraction, 69% vs 84%; p <.05). After the meal, CCK and PYY levels showed higher, persistent elevation in elderly participants. In this group, postprandial satiety lasted significantly longer than in younger participants, and hunger was suppressed throughout the postprandial period. Antral area directly correlated with satiety and inversely with hunger. Gallbladder volume inversely correlated to satiety.

CONCLUSIONS

This study showed, in a group of healthy elderly people, delayed gastric emptying associated to reduced cholecystic contractility together with higher CCK and PYY serum levels. These modifications facilitated long-lasting satiety and hunger suppression after a meal. This condition may lead to caloric restriction and finally to malnutrition at older ages.

Relationship between gastrointestinal and extra-gastrointestinal symptoms and delayed gastric emptying in functional dyspeptic patients

AIM: Delayed gastric emptying and an enlarged fasting gastric antrum are common findings in functional dyspepsia but their relationship with gastrointestinal (GI), and the frequently associated extra-GI symptoms remains unclear. This study evaluated the relationship between GI and extra-GI symptoms, fasting antral volume and delayed gastric emptying in functional dyspepsia.

METHODS: In 108 functional dyspeptic patients antral volume and gastric emptying were assessed with ultraso-nography (US). Symptoms were assessed with standardized questionnaire. The association of symptoms and fasting antral volume with delayed gastric emptying was estimated with logistic regression analysis.

RESULTS: Delayed gastric emptying was detected in 39.8% of the patients. Postprandial drowsiness (AOR 11.25; 95%CI 2.75-45.93), nausea (AOR 3.51; 95%CI 1.19-10.32), fasting antral volume (AOR 1.93; 95%CI 1.22-3.05), were significantly associated with delayed gastric emptying. Symptoms, mainly the extra-GI ones as postprandial drowsiness and nausea, combined with fasting antral volume predicted the modality of gastric emptying with a sensitivity and specificity of 78%.

CONCLUSION: In functional dyspeptic patients, (1) an analysis of fasting antral volume and of symptoms can offer valuable indication on the modality of gastric emptying, and (2) it seems appropriate to inquire on postprandial drowsiness that showed the best correlation with delayed gastric emptying.

THE EFFECT OF ETHANOL AND ALCOHOLIC BEVERAGES ON GASTRIC EMPTYING OF SOLID MEALS IN HUMANS

AIMS

The systematic study of the effect of pure ethanol, alcoholic beverages, and their non-alcoholic components on gastric emptying of solid meals in humans.

METHODS

16 fasting healthy male subjects received once weekly 300 ml of the following solutions in random order: 4 and 10% (v/v) ethanol, beer, red wine, 5.5 and 11.4% (w/v) glucose, and water. The test solutions were given either together with a low caloric (270 kcal, n = 8) or a high caloric (740 kcal, n = 8) solid meal. Ultrasonography of the antrum was used to determine gastric emptying.

RESULTS

Gastric half emptying time (t(1/2) ) of the high caloric solid meal with water was 131.3 +/- 7 min. The ingestion of 4 and 10% (v/v) ethanol (158.8 +/- 9.3 and 165.6 +/- 6.2 min, respectively), beer (163.1 +/- 11 min), and red wine (186.3 +/- 8.4 min) resulted in a significantly longer t(1/2) than water. The lag phases after 4 and 10% (v/v) ethanol, beer, and red wine were not significantly different from that of water (48.1 +/- 6.5 min). Compared with water, the ingestion of 5.5 and 11.4% (w/v) glucose resulted in a significantly longer t(1/2) (153.8 +/- 5 and 168.1 +/- 14.4 min, respectively) by increasing the duration of the lag phase. The high caloric meals resulted in a 2-fold prolongation of t(1/2) when compared with the low caloric meals. The effect of the solutions on the gastric emptying times, however, was similar for both test meals.

CONCLUSIONS

(i) Ethanol in low concentrations of 4 and 10% (v/v) prolongs gastric emptying of solid meals; this inhibitory effect is not dose-dependent. (ii) Alcoholic beverages (beer and red wine) also result in a prolongation of gastric emptying. The inhibitory effect of red wine, but not of beer, is more pronounced than that of the corresponding ethanol concentration and amount. (iii) The inhibitory effect of ethanol and alcoholic beverages is mainly induced by a prolongation of the gastric emptying phase (without affecting the lag phase), whereas 5.5 and 11.4% (w/v) glucose prolong the lag phase in a dose-dependent manner. (iv) The inhibitory effect of ethanol, beer, and red wine on gastric emptying does not depend on the caloric content of the meal.

Comparison of the carbon 13-labeled octanoic acid breath test and ultrasonography for assessment of gastric emptying of a semisolid meal in dogs

OBJECTIVE

To compare the rate of gastric emptying of a semisolid meal by use of the carbon 13-labeled octanoic acid breath test (13C-OBT) and gastric emptying ultrasonography (GEU) in dogs.

ANIMALS

10 healthy dogs.

PROCEDURE

Food was withheld from dogs for 12 hours before ingestion of a test meal (bread, egg, and skimmed milk) containing 13C-octanoic acid. The gastric antrum was visualized by use of a 6.5-MHz microconvex transducer, and the area of the ellipse defined by the craniocaudal and ventrodorsal diameters of the stomach was measured. Samples of expired air and antral images were obtained 30 minutes before ingestion of the test meal and then every 15 minutes for 4 hours and every 30 minutes for a further 2 hours. The half-dose recovery time with the 13C-OBT (t1/2[BT]) and the gastric half emtying time with GEU (t50%[GEU]) was calculated.

RESULTS

Mean +/- SD values for the t1/2(BT) and t50%(GEU) were 3.44 +/- 0.48 hours and 1.89 +/- 0.78 hours, respectively. A significant correlation was detected between the t1/2(BT) and t50%(GEU), although there was a large (1.55 hours) mean difference between these indices.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that there was a correlation between the rate of solid-phase gastric emptying assessed by use of GEU and the 13C-OBT in dogs. Gastric emptying ultrasonography may be a useful, noninvasive method for assessment of the rate of solid-phase gastric emptying in dogs.

American Gastroenterological Association technical review on the diagnosis and treatment of gastroparesis

This literature review and the recommendations herein were prepared for the American Gastroenterological Association Clinical Practice Committee. The paper was approved by the Committee on May 16, 2004, and by the AGA Governing Board on September 23, 2004.

Reliability of the [13C]-acetate breath test in the measurement of gastric emptying of ethanol solutions: a methodological study

BACKGROUND

The [13C]-acetate breath test is a clinically well-established test for measuring gastric emptying of liquids and correlates significantly with scintigraphy. However, no studies have been undertaken to examine the relationship between gastric emptying measured by the [13C]-acetate breath test and ultrasonography. Furthermore, it is not known how ethanol may affect gastric emptying as measured by the [13C]-acetate breath test. This is particularly important because of the additional steps of absorption, metabolism and exhalation of the tracer involved in the [13C]-acetate breath test compared to the simple measurement of gastric emptying by ultrasonography. The aim of the present study was to examine the relationship between the gastric half emptying times measured by the [13C]-acetate breath test and by ultrasonography and to determine the effect of ethanol on the comparability between both methods.

METHODS

On separate days, 10 healthy, fasted randomly selected subjects received the following solutions by gastric tube: 500 mL water, 4% and 10% (v/v) ethanol, 5.5% and 11.4 % (w/v) glucose. Gastric half emptying times of the test solutions were simultaneously determined using the [13C]-acetate breath test and ultrasonography of the fundus and the antrum.

RESULTS

The gastric emptying rates determined by ultrasonography of the fundus correlated significantly with the results obtained using the [13C]-acetate breath test for all test solutions (r = 0.64-0.92, P < 0.05 for all), whereas ultrasonography of the antrum correlated significantly with the breath test only when water (r = 0.94, P = 0.001) was used. The difference between the mean half-emptying times obtained using the [13C]-acetate breath test and ultrasonography of the fundus was 55 +/- 1.8 min. This difference was significantly longer when 4% and 10% (v/v) ethanol solutions were given (61.2 +/- 3.3 and 71.2 +/- 2.9 min) compared to water (P < 0.05).

CONCLUSIONS

A good correlation was found between gastric emptying as measured by the [13C]-acetate breath test and ultrasonography of the fundus. Measurements that were obtained using the [13C]-acetate breath test demonstrate a longer gastric half emptying time compared with those obtained using ultrasonography. This difference is even more marked when ethanol solutions are used. Presumably, this is because ethanol affects the absorption and/or the hepatic metabolism of the tracer. The [13C]-acetate breath test is therefore not a reliable gastric emptying test for comparison of different solutions, especially when ethanol-containing liquids are used.

A review of methods for assessment of the rate of gastric emptying in the dog and cat: 1898-2002

Gastric emptying is the process by which food is delivered to the small intestine at a rate and in a form that optimizes intestinal absorption of nutrients. The rate of gastric emptying is subject to alteration by physiological, pharmacological, and pathological conditions. Gastric emptying of solids is of greater clinical significance because disordered gastric emptying rarely is detectable in the liquid phase. Imaging techniques have the disadvantage of requiring restraint of the animal and access to expensive equipment. Radiographic methods require administration of test meals that are not similar to food. Scintigraphy is the gold standard method for assessment of gastric emptying but requires administration of a radioisotope. Magnetic resonance imaging has not yet been applied for assessment of gastric emptying in small animals. Ultrasonography is a potentially useful, but subjective, method for assessment of gastric emptying in dogs. Gastric tracer methods require insertion of gastric or intestinal cannulae and are rarely applied outside of the research laboratory. The paracetamol absorption test has been applied for assessment of liquid phase gastric emptying in the dog, but requires IV cannulation. The gastric emptying breath test is a noninvasive method for assessment of gastric emptying that has been applied in dogs and cats. This method can be carried out away from the veterinary hospital, but the effects of physiological and pathological abnormalities on the test are not known. Advances in technology will facilitate the development of reliable methods for assessment of gastric emptying in small animals.

Correlation between simultaneous scintigraphic and ultrasonographic measurement of gastric emptying in patients with type 1 diabetes mellitus

OBJECTIVE

To compare scintigraphic measurements of total stomach emptying of a semisolid meal with ultrasonographic measurements of changes in antral area as estimates of antral emptying in type 1 diabetic patients.

METHODS

Eleven patients with insulin-dependent diabetes mellitus were studied with simultaneous measurements of gastric emptying by scintigraphy and ultrasonography. Patients were imaged immediately after ingestion (time 0) and every 15 minutes over 120 minutes. The gastric emptying rate was expressed as percent reduction in antral cross-sectional area from 15 to 90 minutes after meal ingestion.

RESULTS

Ultrasonographic measurements showed a postprandial maximal antral area at 15 minutes, continuously decreasing with time, and reaching a plateau 45 to 90 minutes after the end of meal ingestion, whereas the scintigraphic counts attained their maximum immediately after the meal and began to fall thereafter. Between 15 and 90 minutes, the residual radioactivity and antral ultrasonographically measured distension curves were concordant. The curves then showed a tendency toward deviation for the last 15 minutes (median, 51% versus 59% at 105 minutes and 40% versus 57% at 120 minutes, respectively). A strong significant correlation could be seen between the ultrasonographic gastric emptying rate and scintigraphic half-time values (r = -0.94; P < .001). Comparing scintigraphic and ultrasonographic half-time values showed a systematic measurement error of 9.9 minutes and a random measurement error of 18.6 minutes.

CONCLUSIONS

The use of standardized real-time ultrasonography to determine the gastric emptying rate of semisolid meals in diabetic patients, with the use of the change in gastric antral cross-sectional area in a single section of the stomach 15 and 90 minutes postprandially, offers a valid method for clinical practice.

Octreotide enhances the accelerating effect of erythromycin on gastric emptying in healthy subjects

BACKGROUND

Erythromycin exhibits gastrokinetic properties through cholinergic pathways. Reports regarding the action of octreotide on gastric emptying are conflicting.

AIM

: To assess: (i) the hypothesis that serotonin receptors are involved in the accelerating effect of erythromycin on gastric emptying; and (ii) any modification of the gastrokinetic action of erythromycin induced by octreotide.

SUBJECTS AND METHODS

Gastric emptying of a standard meal was estimated in 20 healthy subjects by scintigraphy on three different occasions in a double-blind, placebo-controlled manner and in random order: (i) after placebo; (ii) after 200 mg of intravenous erythromycin; and (iii) after 200 mg of intravenous erythromycin following pre-treatment with either 4 mg of intravenous ondansetron (10 subjects) or 50 micro g octreotide.

RESULTS

Erythromycin significantly accelerated gastric emptying in all subjects by abolishing the lag phase. Pre-treatment with ondansetron abolished the accelerating effect of erythromycin by restoring the emptying times to placebo levels. Octreotide significantly enhanced the accelerating effect of erythromycin by reducing both the lag and post-lag phases of gastric emptying.

CONCLUSIONS

Serotonin receptors are involved in the accelerating effect of erythromycin on gastric emptying. This effect seems to be enhanced by pre-treatment with octreotide, possibly as a result of the modification of the gastrointestinal hormonal environment.

Gastric emptying in myotonic dystrophic patients

BACKGROUND

Myotonic dystrophy is often associated with digestive symptoms that can precede the clinical appearance of skeletal muscle involvement. Although motility disorders may be observed in these patients at any level of the gastrointestinal tract, upper gastrointestinal symptoms have up to now usually been considered to be due to oesophageal rather than gastric dysmotility.

AIMS

To evaluate: a) gastric emptying in myotonic dystrophic patients without dyspeptic symptoms, and b) relationship between gastric emptying and severity and duration of the disease.

PATIENTS AND METHODS

Gastric emptying was evaluated in 11 non-dyspeptic dystrophic patients and in 22 healthy volunteers by means of computerised ultrasound scan, assessing the variation in the antral area over time after ingestion of a meal.

RESULTS

The final emptying time was higher in patients than in healthy volunteers (373' +/- 35' vs 270' +/- 47'; p < 0.001). Basal and maximal post-prandial antral areas were similar in the two groups. There was a significant correlation between gastric emptying and the duration of the disease (rs = 0.62; p = 0.04). No relationship was found between gastric emptying and severity of the disease.

CONCLUSIONS

Gastric emptying may be abnormally delayed in myotonic dystrophy patients, even in absence of dyspeptic symptoms. This delay is correlated with duration but not with severity of the disease. However there is no difference in either basal or maximal postprandial antral areas between myotonic dystrophy patients and healthy volunteers.