Efficacy of guar gum in preventing the dumping syndrome

Postbariatric surgery hypoglycemia: Nutritional, pharmacological and surgical perspectives

Post-bariatric hypoglycaemia (PBH) is a metabolic complication of bariatric surgery (BS), consisting of low post-prandial glucose levels in patients having undergone bariatric procedures. While BS is currently the most effective and relatively safe treatment for obesity and its complications, the development of PBH can significantly impact patients' quality of life and mental health. The diagnosis of PBH is still challenging, considering the lack of definitive and reliable diagnostic tools, and the fact that this condition is frequently asymptomatic. However, PBH's prevalence is alarming, involving up to 88% of the post-bariatric population, depending on the diagnostic tool, and this may be underestimated. Given the prevalence of obesity soaring, and an increasing number of bariatric procedures being performed, it is crucial that physicians are skilled to diagnose PBH and promptly treat patients suffering from it. While the milestone of managing this condition is nutritional therapy, growing evidence suggests that old and new pharmacological approaches may be adopted as adjunct therapies for managing this complex condition.

Dumping Syndrome in Children: A Narrative Review

Dumping syndrome (DS) is a typical side effect of stomach surgery, which includes cancer, non-cancer esophageal and gastric surgery, and bariatric surgery. It is marked by the fast evacuation of undigested food from the stomach into the small intestine, which causes a variety of symptoms. Early dumping symptoms include gastrointestinal symptoms such as stomach discomfort, diarrhea, and nausea, as well as vasomotor symptoms such as drowsiness and face flushing, and occur within the first hour following a meal. Late dumping symptoms appear one to three hours after a meal and are related to reactive hypoglycemia, resulting in hypoglycemia, sweating, palpitations, and confusion. Early dumping pathophysiology involves abnormalities in stomach structure and function, which result in rapid transit of stomach contents to the duodenum, insufficient digestion, and fluid transfers from the vascular compartment to the intestine. Late dumping occurs as a result of hyperinsulinemia caused by the fast passage of undigested foods to the gut. Symptom-based questionnaires and diagnostic testing such as plasma glucose measurement and stomach emptying studies can be used to confirm a diagnosis of DS. The primary approach to managing DS is dietary modifications, including eating smaller, more frequent meals and avoiding high glycemic index carbohydrates. Dietary supplements and medications may be used to slow down gastric emptying or control blood glucose levels. Pharmacological options include alpha-glycosidase inhibitors, somatostatin analogs, glucagon-like peptide-1 analogs, and sodium-glucose cotransporter inhibitors. In severe cases, refractory to conservative measures, surgical interventions may be considered. DS can arise in children following gastric surgery for obesity or corrective surgery for congenital abnormalities. It is frequently misdiagnosed and can have serious implications, such as hypoglycemia-related cognition deficits. Screening and early identification using glucose tolerance testing and continuous glucose monitoring (CGM) are critical in at-risk youngsters. Children's treatment techniques are similar to those used in adults, with dietary changes and medication therapies serving as the cornerstone of care. Overall, DS is a complex condition that requires a multidisciplinary approach to diagnosis and management. Further research is needed to improve understanding of its pathophysiology and optimize treatment strategies, particularly in children. This review aims to provide a well-rounded informative summary of the most recent literature on the under-recognized clinical and scientific aspects of DS among the children age group. It incorporates the quality of life, pathophysiology, diagnosis, prevalence, and treatment.

Weight Recidivism and Dumping Syndrome after Roux-En-Y Gastric Bypass: Exploring the Therapeutic Role of Transoral Outlet Reduction

Obesity is a chronic, relapsing disease representing a global epidemic. To date, bariatric surgery is the most effective treatment for morbid obesity in the long-term. Roux-en-Y gastric bypass (RYGB) is one of the most performed bariatric interventions, with excellent long-term outcomes. However, about one-third of patients may experience weight regain over time, as well as dumping syndrome. Both these conditions are challenging to manage and require a multidisciplinary and personalized approach. The dilation of the gastro-jejunal anastomosis is a recognized etiological factor for both weight regain and dumping syndrome. Dietary modifications, behavioral interventions, and medications represent the first therapeutic step. Revisional surgery is the traditional approach when non-invasive treatments fail. However, re-interventions may be technically difficult and are associated with increased morbidity and mortality. Transoral outlet reduction (TORe) is an endoscopic procedure aimed at reducing the size of the anastomosis and is proposed as a minimally invasive treatment of weight regain and/or dumping syndrome refractory to conservative therapies. This review is aimed at providing a narrative overview of the role of TORe as part of the multidisciplinary therapeutic toolkit nowadays available to approach weight regain and dumping syndrome after RYGB.

International consensus on the diagnosis and management of dumping syndrome

Dumping syndrome is a common but underdiagnosed complication of gastric and oesophageal surgery. We initiated a Delphi consensus process with international multidisciplinary experts. We defined the scope, proposed statements and searched electronic databases to survey the literature. Eighteen experts participated in the literature summary and voting process evaluating 62 statements. We evaluated the quality of evidence using grading of recommendations assessment, development and evaluation (GRADE) criteria. Consensus (defined as >80% agreement) was reached for 33 of 62 statements, including the definition and symptom profile of dumping syndrome and its effect on quality of life. The panel agreed on the pathophysiological relevance of rapid passage of nutrients to the small bowel, on the role of decreased gastric volume capacity and release of glucagon-like peptide 1. Symptom recognition is crucial, and the modified oral glucose tolerance test, but not gastric emptying testing, is useful for diagnosis. An increase in haematocrit >3% or in pulse rate >10 bpm 30 min after the start of the glucose intake are diagnostic of early dumping syndrome, and a nadir hypoglycaemia level <50 mg/dl is diagnostic of late dumping syndrome. Dietary adjustment is the agreed first treatment step; acarbose is effective for late dumping syndrome symptoms and somatostatin analogues are preferred for patients who do not respond to diet adjustments and acarbose.

Gastroparesis and Dumping Syndrome: Current Concepts and Management

Gastroparesis and dumping syndrome both evolve from a disturbed gastric emptying mechanism. Although gastroparesis results from delayed gastric emptying and dumping syndrome from accelerated emptying of the stomach, the two entities share several similarities among which are an underestimated prevalence, considerable impairment of quality of life, the need for a multidisciplinary team setting, and a step-up treatment approach. In the following review, we will present an overview of the most important clinical aspects of gastroparesis and dumping syndrome including epidemiology, pathophysiology, presentation, and diagnostics. Finally, we highlight promising therapeutic options that might be available in the future.

Dumping syndrome after esophageal, gastric or bariatric surgery: pathophysiology, diagnosis, and management

BACKGROUND

Dumping syndrome, a common complication of esophageal, gastric or bariatric surgery, includes early and late dumping symptoms. Early dumping occurs within 1 h after eating, when rapid emptying of food into the small intestine triggers rapid fluid shifts into the intestinal lumen and release of gastrointestinal hormones, resulting in gastrointestinal and vasomotor symptoms. Late dumping occurs 1-3 h after carbohydrate ingestion, caused by an incretin-driven hyperinsulinemic response resulting in hypoglycemia. Clinical recommendations are needed for the diagnosis and management of dumping syndrome.

METHODS

A systematic literature review was performed through February 2016. Evidence-based medicine was used to develop diagnostic and management strategies for dumping syndrome.

RESULTS

Dumping syndrome should be suspected based on concurrent presentation of multiple suggestive symptoms after upper abdominal surgery. Suspected dumping syndrome can be confirmed using symptom-based questionnaires, glycemia measurements and oral glucose tolerance tests. First-line management of dumping syndrome involves dietary modification, as well as acarbose treatment for persistent hypoglycemia. If these approaches are unsuccessful, somatostatin analogues should be considered in patients with dumping syndrome and impaired quality of life. Surgical re-intervention or continuous enteral feeding may be necessary for treatment-refractory dumping syndrome, but outcomes are variable.

CONCLUSIONS

Implementation of these diagnostic and treatment recommendations may improve dumping syndrome management.

Post-gastric bypass hypoglycaemia: a review

Bariatric surgery is a highly effective treatment for severe obesity, resulting in substantial weight loss and normalizing obesity-related comorbidities. However, long-term consequences can occur, such as postbariatric surgery hypoglycaemia. This is a challenging medical problem, and the number of patients presenting with it has been increasing. Roux-en-Y gastric bypass (RYGB) is the most popular bariatric procedure, and it is the surgery most commonly associated with the development of postbariatric surgery hypoglycaemia. To date, the pathogenesis of this condition has not been completely established. However, various factors - particularly increased postprandial glucagon-like peptide (GLP)-1 secretion - have been considered as crucial mediator. The mechanisms responsible for diabetic remission after bariatric surgery may be responsible for the development of hypoglycaemia, which typically occurs 1-3 h after a meal and is concurrent with inappropriate hyperinsulinaemia. Carbohydrate-rich foods usually provoke hypoglycaemic symptoms, which can typically be alleviated by strict dietary modifications, including carbohydrate restriction and avoidance of high glycaemic index foods and simple sugars. Few patients require further medical intervention, such as medications, but some patients have required a pancreatectomy. Because this option is not always successful, it is no longer routinely recommended. Clinical trials are needed to further determine the pathophysiology of this condition as well as the best diagnostic and treatment approaches for these patients.

[Dumping syndrome: Diagnostics and therapeutic options]

BACKGROUND

Dumping syndrome is a common complication after surgery of the upper gastrointestinal tract with symptoms ranging from mild gastrointestinal discomfort and moderate vasomotor disturbances, to severe hyperinsulinemic hypoglycemia. Due to the increasing number of bariatric procedures being performed worldwide, bariatric surgery has become the most common cause for this disease entity.

OBJECTIVE

The aim of this review is to highlight the evidence for the physiological mechanisms contributing to dumping syndrome after the two most common bariatric surgery procedures, Roux-en-Y gastric bypass and sleeve gastrectomy, to discuss technical aspects of the procedures underlying the development of the syndrome, patient-related predictive factors and other differential diagnoses, together with diagnostic and therapeutic algorithms.

Postgastrectomy nutrition

Gastric resection, whether partial or total gastrectomy, often results in nutrition-related complications including weight loss, diet intolerances, and micronutrient deficiencies. The physiology of normal and postgastrectomy digestion is the basis for most of the current diet recommendations after gastric surgery. A careful review reveals that there is not sufficient literature to support a standard postgastrectomy diet. Rather, individualized diet manipulation for symptom relief is recommended. This review highlights the physiology behind common postgastrectomy complications, provides guidelines for the medical and nutrition management of these complications, and presents a basic approach to postgastrectomy gastrointestinal symptoms.

Pathophysiology, diagnosis and management of postoperative dumping syndrome

Dumping syndrome is a frequent complication of esophageal, gastric or bariatric surgery. Rapid gastric emptying, with the delivery to the small intestine of a significant proportion of solid food as large particles that are difficult to digest, is a key event in the pathogenesis of this syndrome. This occurrence causes a shift of fluid from the intravascular component to the intestinal lumen, which results in cardiovascular symptoms, release of several gastrointestinal and pancreatic hormones and late postprandial hypoglycemia. Early dumping symptoms comprise both gastrointestinal and vasomotor symptoms. Late dumping symptoms are the result of reactive hypoglycemia. Besides the assessment of clinical alertness and endoscopic or radiological imaging, a modified oral glucose tolerance test might help to establish a diagnosis. The first step in treating dumping syndrome is the introduction of dietary measures. Acarbose can be added to these measures for patients with hypoglycemia, whereas several studies advocate guar gum or pectin to slow gastric emptying. Somatostatin analogs are the most effective medical therapy for dumping syndrome, and a slow-release preparation is the treatment of choice. In patients with treatment-refractory dumping syndrome, surgical reintervention or continuous enteral feeding can be considered, but the outcomes of such approaches are variable.

Efficacy of the long-acting repeatable formulation of the somatostatin analogue octreotide in postoperative dumping

BACKGROUND & AIMS

Several studies have established symptomatic and mechanistic benefits of the somatostatin analogue octreotide in patients with dumping syndrome, but clinical use is hampered by the requirement for subcutaneous administration 3 times daily. We compared the efficacy of subcutaneous octreotide with that of the long-acting repeatable (LAR) octreotide formulation, which is administered monthly, in patients with dumping syndrome.

METHODS

The study included 30 consecutive patients with postoperative dumping, evidenced by oral glucose tolerance test (OGTT) results and insufficient response to dietary measures. OGTT, dumping severity score (summary of scores 0-3 for 8 early and 6 late dumping symptoms), and quality-of-life data were evaluated at baseline, after 3 days of subcutaneous administration of octreotide (0.5 mg), and then after 3 monthly intramuscular injections of octreotide LAR (20 mg).

RESULTS

Both formulations of octreotide significantly reduced total dumping severity scores (21.7 +/- 1.6 at baseline, 11.2 +/- 1.2 for subcutaneous and 14.0 +/- 1.8 for LAR formulations; P < .05). This reduction was associated with significant improvements in the increase in pulse rate (13.8 +/- 5.8 at baseline vs -0.3 +/- 2.2 and 1.9 +/- 1.7; P < .05) as well as the increase in hematocrit level (4.0 +/- 1.4 at baseline vs 0.3 +/- 0.9. and 0.4 +/- 1.0; P < .05), and the lowest glycemia level in the OGTT (54.1 +/- 6.7 at baseline vs 98.9 +/- 7.1 and 67.8 +/- 5.9; P < .05). LAR octreotide administration significantly improved patients' quality of life. Patients' evaluations of their overall treatment efficacy was higher on LAR compared with the subcutaneous formulation (83% vs 52%; P = .01). Gallbladder stones occurred in 4 patients.

CONCLUSIONS

Monthly administration of LAR octreotide improves OGTT results, symptoms, and quality of life in patients with postoperative dumping.

Functional Conduit Disorders After Esophagectomy

Unfortunately normal gastrointestinal function after an esophagectomy is rare. Most patients will never eat the way they did before their illness. Most patients require smaller more frequent meals. It is common for patients to loose up to 15% of their body weight from the time of diagnosis through the first 6 months postoperatively, but fortunately this trend levels off after 6 months. Dumping syndrome, delayed gastric emptying, reflux, and dysphagia can all contribute to nutritional deficiency and poor quality of life. There is no one surgical modification to eliminate any one of these complications, but several guidelines can help reduce conduit dysfunction. Most patients seem to benefit from a 5-cm-wide greater-curvature gastric tube brought up through the posterior mediastinum. The gastric-esophageal anastomosis should be placed higher than the level of the azygous vein. Drainage procedures seem to be helpful, especially when using the whole stomach as a conduit. Early erythromycin therapy significantly aids in the function of the gastric conduit. Proton-pump inhibitors are important for improvement of postoperative reflux symptoms and to help prevent Barrett's metaplasia in the esophageal remnant. Single-layer hand-sewn or semi-mechanical anastomoses provide greater cross-sectional area and fewer problems with stricture. When benign strictures occur, early endoscopy and dilation with proton-pump inhibition greatly reduces the morbidity. Patients should be instructed to eat six small meals a day and to remain upright for as long as possible after eating. Simple sugars and fluid at mealtime should be avoided until the function of the conduit is established.

Dumping syndrome: pathophysiology and treatment

Anatomic and physiologic changes introduced by gastric surgery result in clinically significant dumping syndrome in approximately 10% of patients. Dumping is the effect of alteration in the motor functions of the stomach, including disturbances in the gastric reservoir and transporting function. Gastrointestinal hormones play an important role in dumping by mediating responses to surgical resection. Treatment options of dumping syndrome include diet, medications, and surgical revision. Poor nutrition status can be anticipated in patients who fail conservative therapy. Management of refractory dumping syndrome can be a challenge. This review highlights current knowledge about the mechanisms of dumping syndrome and available therapy.

Dumping Syndrome

The dumping syndrome consists of early postprandial abdominal and vasomotor symptoms, resulting from osmotic fluid shifts and release of vasoactive neurotransmitters, and late symptoms secondary to reactive hypoglycemia. Effective relief of symptoms of dumping syndrome can be achieved with dietary modifications to minimize ingestion of simple carbohydrates and to exclude fluid intake during ingestion of the solid portion of the meal. More severely affected individuals may respond to agents such as pectin and guar, which increase the viscosity of intraluminal contents, or to drugs such as the alpha-glucosidase inhibitor acarbose, which blunts the rapid absorption of glucose, and the somatostatin analog octreotide, which alters gut transit and impairs release of vasoactive mediators into the bloodstream.

Guar gum for body weight reduction: meta-analysis of randomized trials

PURPOSE

To determine the efficacy of the dietary fiber guar gum as a therapeutic option for reducing body weight by conducting a meta-analysis of randomized controlled trials.

METHODS

Literature searches were performed on the electronic databases Medline, Embase, Biosis, Amed, and the Cochrane Library. Manufacturers of commercial guar gum preparations and experts on the subject were contacted to provide any published or unpublished trials. For inclusion, trials had to state that they were randomized, double blinded, and placebo controlled, used guar gum monopreparations, and reported body weight as an endpoint. No language restrictions were imposed. Two reviewers independently extracted data in a standardized manner according to predefined criteria and evaluated methodological quality using the scoring system developed by Jadad. Discrepancies were settled through discussion.

RESULTS

Thirty-four trials were identified and 20 could be included. Eleven trials provided data that were suitable for statistical pooling. The meta-analysis indicated a nonsignificant difference in patients receiving guar gum compared with patients receiving placebo (weighted mean difference -0.04 kg; 95% confidence interval (CI): -2.2 to 2.1). Analysis of six trials with similar methodologic features corroborates these findings (weighted mean difference -0.3 kg; 95% CI: -4.0 to 3.5). Adverse events most frequently reported were abdominal pain, flatulence, diarrhea, and cramps. Overall, 11 patients (3%) dropped out owing to adverse events.

CONCLUSIONS

This meta-analysis suggests that guar gum is not efficacious for reducing body weight. Considering the adverse events associated with its use, the risks of taking guar gum outweigh its benefits for this indication. Therefore, guar gum cannot be recommended as a treatment for lowering body weight.

Benefit of uncooked cornstarch in the management of children with dumping syndrome fed exclusively by gastrostomy

OBJECTIVES

Children with dumping syndrome fed exclusively by gastrostomy are difficult to manage because liquid diets are given directly into the antrum. The gastric contents are emptied rapidly into the small intestine, with consequent hyperglycemia followed by a delayed hypoglycemia and multiple, often debilitating, symptoms. Uncooked cornstarch is a complex carbohydrate that provides a slow and continuous glucose source and may delay gastric emptying. The objective of this study was to determine the efficacy of uncooked cornstarch in the treatment of these children.

METHODS

The medical records of eight children with dumping syndrome fed exclusively by gastrostomy were reviewed. Dumping syndrome was diagnosed if there was consistent symptomatology, rapid gastric emptying, and abnormal glucose measurements after a glucose tolerance test. Enough uncooked cornstarch to match hepatic glucose production for 4 h was added to control hypoglycemia, and the feeding formula was modified to control hyperglycemia.

RESULTS

All patients had debilitating symptoms. Weight z-score on admission was -2.31 +/- 0.29. Glucose shifts were controlled in all. There was a significant difference between the maximum (221.3 +/- 19.3 mg/dl vs 121.3 +/- 6.9 mg/dl; p < 0.008) and minimum serum glucose (47 +/- 7.8 mg/dl vs 65.6 +/- 4 mg/dl; p < 0.04) before and after uncooked cornstarch. Weight increased from 11.87 +/- 1.4 kg to 15.10 +/- 2.3 kg (p = 0.06). In seven patients, bolus feedings were successfully administered, and symptoms improved or resolved.

CONCLUSIONS

Uncooked cornstarch controlled the glucose shifts, resolved most of the symptoms, allowed bolus feedings, and enhanced weight gain in these children.

Preoperative and postoperative motility disorders of the stomach

Improved technology has expanded the study and understanding of gastrointestinal motility. Although no clear cause and effect relation has been demonstrated, altered motility has been found in association with a variety of nonsurgical and postoperative settings. As this relation is better defined, perhaps patients who are at risk to develop complications of surgery can be better identified so that treatment can be tailored toward their specific defect. Technological advances can also be expected to provide new and more effective interventions in this expanding field.

Dumping syndrome in children. Diagnosis and effect of glucomannan on glucose tolerance and absorption

Dumping syndrome is rarely seen in children. We studied ten children with symptoms following various types of gastric surgery. All had abnormal blood glucose and breath hydrogen responses after oral glucose challenge, indicating reduction of both glucose tolerance and glucose absorption, as compared to controls. Glucose tolerance was best expressed as the difference between peak and subsequent lowest blood glucose level, the upper limit of normal (mean + 3 SD) being 5.9 mmol/l. In eight children with persisting symptoms we tested the effects of glucomannan, a highly hygroscopic tasteless fibre, on glucose tolerance and glucose absorption. Glucomannan significantly improved glucose tolerance, but did have no overall effect on glucose absorption. Four children tested glucomannan added to the main meals. Breath hydrogen excretion, as established with the daytime breath hydrogen profile, decreased significantly in two, but complaints increased in three children. Glucomannan does not appear to be suitable for the treatment of dumping syndrome in children as the side effects seem to overrule the beneficial effects.

Postgastrectomy syndromes

The most common types of postgastrectomy disorders are the dumping syndromes (early postprandial and late or hypoglycemic) and alkaline reflux gastritis. Both are caused by destruction of the pyloric mechanism. A third problem, Roux-en-Y duodenal diversion, frequently results in delayed gastric emptying.