Pyloric distensibility measurement predicts symptomatic response to intrapyloric botulinum toxin injection

European Guideline on Chronic Nausea and Vomiting-A UEG and ESNM Consensus for Clinical Management

INTRODUCTION

Chronic nausea and vomiting are symptoms of a wide range of gastrointestinal and non-gastrointestinal conditions. Diagnosis can be challenging and requires a systematic and well-structured approach. If the initial investigation for structural, toxic and metabolic disorders is negative, digestive motility and gut-brain interaction disorders should be assessed. United European Gastroenterology (UEG) and the European Society for Neurogastroenterology and Motility (ESNM) identified the need for an updated, evidence-based clinical guideline for the management of chronic nausea and vomiting.

METHODS

A multidisciplinary team of experts in the field, including European specialists and national societies, participated in the development of the guideline. Relevant questions were addressed through a literature review and statements were developed and voted on according to a Delphi process.

RESULTS

Ninety-eight statements were identified and voted following the Delphi process. Overall agreement was high, although the grade of scientific evidence was low in many areas. Disagreement was more evident for some pharmacological treatment options. A diagnostic algorithm was developed, focussing on the differentiating features between gastrointestinal motility and gut-brain interaction disorders with predominant nausea and vomiting.

CONCLUSION

These guidelines provide an evidence-based framework for the evaluation and treatment of patients with chronic nausea and vomiting.

Rome Foundation and international neurogastroenterology and motility societies' consensus on idiopathic gastroparesis

To establish a consensus on the definition and management of idiopathic gastroparesis, international experts (selected by neurogastroenterology and motility societies and initiated by the Rome Foundation) devised 144 statements using the Delphi method, with at least 80% agreement required. This consensus defined idiopathic gastroparesis as the presence of symptoms associated with delayed gastric emptying in the absence of mechanical obstruction. Nausea and vomiting were identified as cardinal symptoms. Frequently co-existing symptoms are early satiation and postprandial fullness. Diagnosis requires the presence of these symptoms alongside delayed gastric emptying, measured by a 4 h scintigraphy or gastric emptying breath test of a mixed composition meal in the absence of mechanical obstruction. Therapeutic options with proven efficacy were sparse. Dietary adjustments, nutritional support (per guidelines from the European Society for Clinical Nutrition and Metabolism for substantial weight loss or intractable vomiting), and opioid cessation were recommended by a consensus opinion. Antiemetic and prokinetic agents were also considered potentially beneficial. This consensus offers a global perspective on idiopathic gastroparesis.

Drugs in focus: Botulinum toxin in the therapy of gastrointestinal disorders in children

What is Known

Botulinum toxin (BoNT) causes muscle relaxation by inhibiting acetylcholine release from presynaptic motor neurons at the neuromuscular junction.

What is New

In children with achalasia, BoNT can be considered only in patients in whom rapid weight gain is important to improve surgical outcomes. BoNT has been suggested for treating cricopharyngeal achalasia and delayed gastric emptying. Anal achalasia and constipation after Hirschsprung disease corrective surgery are very promising indications for BoNT use. In selected children with resistant type of functional constipation and chronic anal fissure, BoNT is a viable option for treating.

Endoscopic pyloromyotomy for treatment of gastroparesis: A new standard or still an experimental approach?

Gastroparesis (GP) can be a severe and debilitating disease. Its pathophysiology is complex and not completely understood. Two principal mechanisms are responsible for the development of symptoms - gastric hypomotility and pylorospasm. Pylorus targeted therapies aim to decrease presumably elevated pyloric tone - pylorospasm. There is a growing body of evidence about their role in the treatment algorithm of GP. G-POEM (endoscopic pyloromyotomy) is an extensively studied pylorus targeted therapy. Its efficacy ranges between 56 and 80% and the number of recurrences among those with treatment effect seems low. G-POEM is a safe procedure with very low frequency of severe adverse events. At present, G-POEM should not be considered as an experimental approach and may be offered to all patients with refractory and severe GP. Nevertheless, G-POEM is not a first line treatment. Conservative measures such as diet modification and pharmacotherapy should always be tried before G-POEM is considered. Further research must focus on better patient selection as at present there are no standardized criteria. Functional imaging such as impedance planimetry (EndoFlip) may hold promise in this regard.

Interventional functional diagnostics in gastrointestinal endoscopy: Combining diagnostic and therapeutic tools in the endoscopy suite with the functional lumen imaging probe

With technical progress of gastrointestinal functional testing, there has been a demand for more comprehensive examination of esophageal physiology and pathophysiology beyond high-resolution manometry. A new interventional technology based on impedance planimetry, the functional lumen imaging probe (FLIP), enables intraluminal measurement of distensibility and compliance of hollow organs. EndoFLIP uses balloon catheters to measure diameter and distension pressure to calculate cross-sectional area and distensibility in different organs (mostly esophagus, stomach, anorectal region) and can be used in wide variety of indications (diagnostics, pre- and post-treatment evaluation) and currently serves as a helpful adjunctive tool in ambiguous clinical cases. EsoFLIP is a therapeutic variation that uses a stiffer balloon catheter allowing for dilation. The trend to simplify the clinical process from diagnosis to treatment tends to a one-session procedure combining diagnostics and therapeutic interventions. In specified conditions like e.g. achalasia or gastroparesis, a combination of EndoFLIP and EsoFLIP procedures may therefore be useful. The aim of this narrative review is to introduce the clinical use of FLIP and its potential benefit in combined diagnostic-therapeutic procedures.

Intrapyloric Botulinum Toxin Injection for Refractory Nausea and Vomiting in Pediatric Patients

OBJECTIVES

Chronic nausea and vomiting may be associated with gastroparesis or other conditions. Poor mechanistic understanding of symptoms often precludes targeted therapy. Numerous case series suggest that intrapyloric botulinum toxin injection (IPBI) may be beneficial in treating gastroparesis and dyspepsia in children. We hypothesized that nausea, vomiting, and other symptoms, independent of gastroparesis, may improve with IPBI. We sought to identify gastric emptying (GE) and manometric patterns in IPBI responders versus nonresponders.

METHODS

Electronic records of 25 pediatric patients who received IPBI for refractory nausea, vomiting, or both were retrospectively reviewed. We assessed symptom improvement post-IPBI and compared symptoms, GE, and antroduodenal manometry (ADM) findings between IPBI responders and nonresponders.

RESULTS

At least one major symptom improved in 19 patients (76%) after IPBI. Of 22 patients completing a GE study, 14 had delayed GE with no significant difference between IPBI responders and nonresponders. Of 22 patients who underwent ADM, 18 had normal fasting peristalsis, 5 had postprandial antral hypomotility, 4 had neuropathic findings, and 19 had pylorospasm. IPBI responders, compared to nonresponders, demonstrated higher antral pressures with feeding ( P < 0.0001) and shorter duration of pylorospasm ( P = 0.0036). Antral pressures did not differ significantly with fasting or following motilin agonists.

CONCLUSIONS

Our findings suggest that IPBI may have therapeutic benefit in pediatric patients with chronic nausea and/or vomiting, independent of gastroparesis. ADM findings of intact antral peristalsis and elevated antral pressures, in conjunction with efficacy of IPBI, support pyloric non-relaxation as a potential contributor to nausea and/or vomiting in pediatric patients.

Impact of anesthetics on pyloric characteristics measured using the EndoFLIP® system in patients with gastroparesis

BACKGROUND

Pyloric distensibility has been reported as a predictive measure in gastroparesis. Measures can be obtained either during endoscopy under anesthesia or in unsedated patients. However, the impact of anesthetic drugs on the results of pyloric characteristics remains unknown. The objective of the present study was to determine the impact of anesthetics on pyloric characteristics measured using EndoFLIP® in patients with gastroparesis.

METHODS

Consecutive patients with gastroparesis from three French tertiary centers were retrospectively analyzed. Patients with a previous history of pyloric intervention were not considered for analysis. Medical records were reviewed for the potential use of anesthetic drugs during EndoFLIP® measurement.

KEY RESULTS

One hundred twenty-five patients were included in the present study [median age: 55.0 years (43.0-66.0)]. Thirty-four patients (27.2%) had pyloric assessment without general anesthesia and 91 patients (72.8%) with general anesthesia. Pyloric pressure at 40 mL of distension was higher in patients with general anesthesia in comparison with patients without general anesthesia [18.7 (13.0-25.6) mmHg vs. 15.4 (11.9-20.7) mmHg; p = 0.044)]. In multivariate analysis, suxamethonium chloride administration was associated with decreased pyloric distensibility (OR: 3.9; 95% CI: 1.3-11.4; p = 0.013) while ephedrine was rather associated with increased pyloric distensibility (OR: 0.3; 95% CI: 0.1-0.9; p = 0.036).

CONCLUSIONS AND INFERENCES

This study is the first to have found an impact of general anesthesia on pyloric measurement using the EndoFLIP®. Therefore, further studies are needed to confirm these findings, if possible, prospective studies.

Use of endolumenal functional lumen imaging probe in investigating paediatric gastrointestinal motility disorders

Investigating gastrointestinal (GI) motility disorders relies on diagnostic tools to assess muscular contractions, peristalsis propagation and the integrity and coordination of various sphincters. Manometries are the gold standard to study the GI motor function but it is increasingly acknowledged that manometries do not provide a complete picture in relation to sphincters competencies and muscle fibrosis. Endolumenal functional lumen imaging probe (EndoFLIP) an emerging technology, uses impedance planimetry to measure hollow organs cross sectional area, distensibility and compliance. It has been successfully used as a complementary tool in the assessment of the upper and lower oesophageal sphincters, oesophageal body, the pylorus and the anal canal. In this article, we aim to review the uses of EndoFLIP as a tool to investigate GI motility disorders with a special focus on paediatric practice. The majority of EndoFLIP studies were conducted in adult patients but the uptake of the technology in paediatrics is increasing. EndoFLIP can provide a useful complementary data to the existing GI motility investigation in both children and adults.

Imaging in Gastroparesis: Exploring Innovative Diagnostic Approaches, Symptoms, and Treatment

Gastroparesis (GP) is a chronic disease characterized by upper gastrointestinal symptoms, primarily nausea and vomiting, and delayed gastric emptying (GE), in the absence of mechanical GI obstruction. The underlying pathophysiology of GP remains unclear, but factors contributing to the condition include vagal nerve dysfunction, impaired gastric fundic accommodation, antral hypomotility, gastric dysrhythmias, and pyloric dysfunction. Currently, gastric emptying scintigraphy (GES) is considered the gold standard for GP diagnosis. However, the overall delay in GE weakly correlates with GP symptoms and their severity. Recent research efforts have focused on developing treatments that address the presumed underlying pathophysiological mechanisms of GP, such as pyloric hypertonicity, with Gastric Peroral Endoscopic Myotomy (G-POEM) one of these procedures. New promising diagnostic tools for gastroparesis include wireless motility capsule (WMC), the 13 carbon-GE breath test, high-resolution electrogastrography, and the Endoluminal Functional Lumen Imaging Probe (EndoFLIP). Some of these tools assess alterations beyond GE, such as muscular electrical activity and pyloric tone. These modalities have the potential to characterize the pathophysiology of gastroparesis, identifying patients who may benefit from targeted therapies. The aim of this review is to provide an overview of the current knowledge on diagnostic pathways in GP, with a focus on the association between diagnosis, symptoms, and treatment.

Gastroparesis: Myths, Misconceptions, and Management

Gastroparesis (GP), a historically vexing disorder characterized by symptoms of nausea, vomiting, abdominal pain, early satiety, and/or bloating, in the setting of an objective delay in gastric emptying, is often difficult to treat and carries a tremendous burden on the quality of patients' lives, as well as the healthcare system in general. Though the etiology of GP has been fairly well defined, much work has been done recently to better understand the pathophysiology of GP, as well as to identify novel effective and safe treatment options. As our understanding of GP has evolved, many myths and misconceptions still abound in this rapidly changing field. The goal of this review is to identify myths and misconceptions regarding the etiology, pathophysiology, diagnosis, and treatment of GP, in the context of the latest research findings which have shaped our current understanding of GP. Recognition and dispelling of such myths and misconceptions is critical to moving the field forward and ultimately advancing the clinical management of what will hopefully become a better understood and more manageable disorder in the future.

Pediatric Neurogastroenterology and Motility Disorders: What Role Does Endoscopy Play?

Although pediatric neurogastroenterology and motility (PNGM) disorders are prevalent, often debilitating, and remain challenging to diagnose and treat, this field has made remarkable progress in the last decade. Diagnostic and therapeutic gastrointestinal endoscopy emerged as a valuable tool in the management of PNGM disorders. Novel modalities such as functional lumen imaging probe, per-oral endoscopic myotomy, gastric-POEM, and electrocautery incisional therapy have changed the diagnostic and therapeutic landscape of PNGM. In this review, the authors highlight the emerging role of therapeutic and diagnostic endoscopy in esophageal, gastric, small bowel, colonic, and anorectal disorders and disorders of gut and brain axis interaction.

2023 update on the clinical management of gastroparesis

INTRODUCTION

Gastroparesis is characterized by symptoms suggesting gastric retention of food and objective evidence of delayed gastric emptying in the absence of a mechanical obstruction. Nausea, vomiting, early satiety, and postprandial fullness are the classic symptoms of gastroparesis. Gastroparesis is increasingly encountered by physicians. There are several recognized etiologies of gastroparesis, including diabetic, post-surgical, medication-induced, post-viral, and idiopathic.

AREAS COVERED

A comprehensive literature review was conducted to identify studies discussing gastroparesis management. Dietary modifications, medication adjustments, glucose control, antiemetic agents, and prokinetic agents are all part of gastroparesis management. In this manuscript, we detail treatments evolving for gastroparesis, including nutritional, pharmaceutical, device, and recent advanced endoscopic and surgical therapies. This manuscript concludes with a speculative viewpoint on how the field will evolve in 5 years' time.

EXPERT OPINION

Identification of the dominant symptoms (fullness, nausea, abdominal pain, and heartburn) helps to direct management efforts of the patients. Treatments for refractory (treatment resistant) symptoms may include gastric electric stimulation and intra-pyloric interventions like botulinum toxin and endoscopic pyloromyotomy. Understanding the pathophysiology of gastroparesis, relating pathophysiologic abnormalities to specific symptoms, new efficacious pharmacotherapies, and better understanding of the clinical predictors of response of therapies, are priorities for future research in the field of gastroparesis.

Gastroparesis: An Evidence-Based Review for the Bariatric and Foregut Surgeon

Gastroparesis is a gastric motility disorder characterized by delayed gastric emptying. It is a rare disease and difficult to treat effectively; management is a dilemma for gastroenterologists and surgeons alike. We conducted a systematic review of the literature to evaluate current diagnostic tools as well as treatment options. We describe key elements in the pathophysiology of the disease, in addition to current evidence on treatment alternatives, including nutritional considerations, medical and surgical options, and related outcomes.

Diagnostic Methods for Evaluation of Gastric Motility-A Mini Review

Gastric motility abnormalities are common in patients with disorders of gut-brain interaction, such as functional dyspepsia and gastroparesis. Accurate assessment of the gastric motility in these common disorders can help understand the underlying pathophysiology and guide effective treatment. A variety of clinically applicable diagnostic methods have been developed to objectively evaluate the presence of gastric dysmotility, including tests of gastric accommodation, antroduodenal motility, gastric emptying, and gastric myoelectrical activity. The aim of this mini review is to summarize the advances in clinically available diagnostic methods for evaluation of gastric motility and describe the advantages and disadvantages of each test.

Targeting the pylorus in gastroparesis: From physiology to endoscopic pyloromyotomy

BACKGROUND

The pylorus plays a key role in the control of gastric content outflow. Impairment of pyloric physiology has been observed in gastroparesis, particularly when associated with diabetes mellitus or opioid intake or after antireflux surgery. New tools have been developed to identify pyloric dysfunction in routine care, including functional luminal impedance planimetry (FLIP). As such, a new therapeutic strategy targeting the pylorus, namely endoscopic pyloromyotomy (G-POEM), has received increasing attention and emerged as a promising treatment for gastroparesis.

PURPOSE

The present review details the involvement of the pyloric pathophysiology in gastroparesis, as well as clinical results of G-POEM according to the current literature.

Using an Endoluminal Functional Lumen Imaging Probe (EndoFLIP™) to Compare Pyloric Function in Patients with Gastroparesis to Patients After Esophagectomy

BACKGROUND

Gastroparesis (GP) occurs in patients after upper gastrointestinal surgery, in patients with diabetes or systemic sclerosis and in idiopathic GP patients. As pyloric dysfunction is considered one of the underlying mechanisms, measuring this mechanism with EndoFLIP™ can lead to a better understanding of the disease.

METHODS

Between November 2021 and March 2022, we performed a retrospective single-centre study of all patients who had non-surgical GP, post-surgical GP and no sign of GP after esophagectomy and who underwent our post-surgery follow-up program with surveillance endoscopies and further exams. EndoFLIP™ was used to perform measurements of the pylorus, and distensibility was measured at 40 ml, 45 ml and 50 ml balloon filling.

RESULTS

We included 66 patients, and successful application of the EndoFLIP™ was achieved in all interventions (n = 66, 100%). We identified 18 patients suffering from non-surgical GP, 23 patients suffering from GP after surgery and 25 patients without GP after esophagectomy. At 40, 45 and 50 ml balloon filling, the mean distensibility in gastroparetic patients was 8.2, 6.2 and 4.5 mm²/mmHg; 5.4, 5.1 and 4.7 mm²/mmHg in post-surgical patients suffering of GP; and 8.5, 7.6 and 6.3 mm²/mmHg in asymptomatic post-surgical patients. Differences between symptomatic and asymptomatic patients were significant.

CONCLUSION

Measurement with EndoFLIP™ showed that asymptomatic post-surgery patients seem to have a higher pyloric distensibility. Pyloric distensibility and symptoms of GP seem to correspond.

A prospective study of intrapyloric botulinum toxin and EndoFLIP in children with nausea and vomiting

BACKGROUND

Intrapyloric botulinum toxin injection (IPBI) is used to treat nausea and vomiting in children, but no prospective pediatric studies exist. The aims of the current study were to assess the efficacy of IPBI in children with refractory nausea or vomiting and to use EndoFLIP as a biomarker of IPBI response.

METHODS

This was a prospective observational cohort study of pediatric patients undergoing IPBI for refractory nausea, vomiting, or feeding difficulties at a tertiary center. Patients completed validated questionnaires at baseline and 1, 2, and 3 months after IPBI. A subset of patients >10 years old underwent pyloric EndoFLIP at the time of IPBI. Symptoms were compared pre- and post-IPBI, and EndoFLIP measurements were assessed in relation to baseline characteristics and response to IPBI.

KEY RESULTS

Forty-five patients (mean age 14.2 ± 6.0 years) received IPBI, and 23 of those patients underwent EndoFLIP. Twenty-nine patients (64%) had symptomatic improvement at 1-month follow-up, including improvements in overall GI symptoms (p = 0.003), nausea and vomiting (p = 0.009), and discomfort when eating (p = 0.006). Symptomatic improvements lasted up to 3 months. There was a trend towards lower pyloric distensibility in patients with delayed versus normal gastric emptying (4.5 ± 3.8 mm2 /mmHg in delayed vs. 8.9 ± 6.6 mm2 /mmHg in normal, p = 0.09), though there were no differences in EndoFLIP measurements between IPBI responders and non-responders (p > 0.05).

CONCLUSIONS AND INFERENCES

The majority of patients responded to IPBI, with significant improvements seen in nausea, vomiting, and discomfort. Pyloric EndoFLIP tended to distinguish baseline delays in gastric emptying, but it did not predict IPBI response in this patient cohort.

Efficacy and safety of endoscopic pyloric balloon dilation in patients with refractory gastroparesis

BACKGROUND AND AIMS

There has been interest in the use of pyloric therapies for the treatment of refractory gastroparesis. However, data on endoscopic pyloric dilation are scarce. We aimed to assess the efficacy and safety of this procedure in refractory gastroparesis.

METHODS

We performed a retrospective analysis of 47 patients referred for refractory gastroparesis, confirmed by gastric emptying scintigraphy, and treated with endoscopic pyloric through-the-scope balloon dilation. The primary endpoint was the effectiveness of the procedure, evaluated with the Gastric Cardinal Symptom Index (GCSI) at 2 and 6 months.

RESULTS

A clinical response, defined by a 1.0 point decrease in the GCSI score, was observed in 25 patients at 2 months (53%) and in 19 patients at 6 months (40%). The mean GCSI score decreased significantly at 2 and 6 months compared to the preoperative score (3.9 ± 0.87 vs 2.3 ± 1.37 and 3.9 ± 0.87 vs 2.9 ± 1.27, respectively; p < 0.0001). No complication was observed. Nine patients had a delayed relapse at 1 year. A second dilation was performed for eight patients and it was effective in five of them (63%). The mean follow-up time of the patients was 27.0 ± 10.4 months. At 2 years, 15 patients still experienced improvement following this treatment (32%). No predictive factor of clinical response was identified.

CONCLUSION

The efficacy of pyloric dilation is 53% at 2 months, with sustained improvement in one third of patients at 2 years. This treatment should be considered as an alternative option to pyloromyotomy.

Endoscopic pyloromyotomy for the treatment of severe and refractory gastroparesis: a pilot, randomised, sham-controlled trial

OBJECTIVE

Endoscopic pyloromyotomy (G-POEM) is a minimally invasive treatment option with promising uncontrolled outcome results in patients with gastroparesis.

DESIGN

In this prospective randomised trial, we compared G-POEM with a sham procedure in patients with severe gastroparesis. The primary outcome was the proportion of patients with treatment success (defined as a decrease in the Gastroparesis Cardinal Symptom Index (GCSI) by at least 50%) at 6 months. Patients randomised to the sham group with persistent symptoms were offered cross-over G-POEM.

RESULTS

The enrolment was stopped after the interim analysis by the Data and Safety Monitoring Board prior to reaching the planned sample of 86 patients. A total of 41 patients (17 diabetic, 13 postsurgical, 11 idiopathic; 46% male) were randomised (21 G-POEM, 20-sham). Treatment success rate was 71% (95% CI 50 to 86) after G-POEM versus 22% (8-47) after sham (p=0.005). Treatment success in patients with diabetic, postsurgical and idiopathic gastroparesis was 89% (95% CI 56 to 98), 50% (18-82) and 67% (30-90) after G-POEM; the corresponding rates in the sham group were 17% (3-57), 29% (7-67) and 20% (3-67).Median gastric retention at 4 hours decreased from 22% (95% CI 17 to 31) to 12% (5-22) after G-POEM and did not change after sham: 26% (18-39) versus 24% (11-35). Twelve patients crossed over to G-POEM with 9 of them (75%) achieving treatment success.

CONCLUSION

In severe gastroparesis, G-POEM is superior to a sham procedure for improving both symptoms and gastric emptying 6 months after the procedure. These results are not entirely conclusive in patients with idiopathic and postsurgical aetiologies.

TRIAL REGISTRATION NUMBER

NCT03356067; ClinicalTrials.gov.

Fasting pyloric diameter and distensibility by functional endoluminal imaging probe in unsedated healthy volunteers

BACKGROUND

Recent studies with functional endoluminal imaging probe (EndoFLIP® ) measure physiologic characteristics of the pylorus. EndoFLIP® has the potential to select optimal candidates for gastric peroral endoscopic myotomy (G-POEM). Normative values of the pylorus using EndoFLIP® have not been established.

METHODS

Twenty-four healthy volunteers (20-56 years old; 15 females) underwent unsedated, transoral EndoFLIP® measurements of the pylorus after 8 h of fasting. Measurements of diameter (DM), balloon pressure, and distensibility index (DI) of the pylorus were obtained twice over 5 min at 40, 50, and 60 ml balloon distensions.

KEY RESULTS

Pyloric DM at 40, 50, and 60 ml balloon distensions were 13.0 ± 2.5, 14.3 ± 1.8, and 17.2 ± 2.0 mm, respectively. DM with 60 ml distension was notably higher than with 40 and 50 ml distensions. Pyloric DI at 40, 50, and 60 ml distensions were 10.9 ± 4.8, 11.3 ± 5.8, and 11.1 ± 4.3 mm2 /mm Hg, respectively (p = 0.86). Linear regression and Bland-Altman plots showed similar distribution of the DM and DI during the second minute compared with the full 5-min measurements at 50 ml distension, as well as between two sequential measurements using 50 ml distension. With 50 ml balloon distension, intraindividual coefficients of variation (COVintra ) for DM and DI were 13.8% and 29.6%, respectively, and interindividual COV (COVinter ) were 12.6% and 51.3%, respectively. Similar reproducibility was obtained with 40 ml balloon distension.

CONCLUSIONS AND INFERENCES

Unsedated EndoFLIP® can be used to characterize human fasting pyloric diameter and distensibility, with best performance observed with 40 ml and 50 ml distensions and data collection during the second minute. Normative values reported serve as reference values for future studies.

Comprehensive characterization of antral and pyloric contractions by high resolution manometry: applied physiology in suspected gastroparesis

Delayed gastric emptying may result from diverse pathophysiological mechanisms including antral hypomotility and pylorospasm. With increasing use of gastric peroral endoscopic myotomy and preliminary evidence of efficacy, our aim was to assess the motor functions of the distal antrum and pylorus in patients with symptoms of gastroparesis using high-resolution antropyloroduodenal manometry (HR-ADM). Sixteen patients with symptoms suggestive of gastroparesis underwent HR-ADM with 13 sensors, 1 cm apart, placed across the antropyloroduodenal (APD) junction and 2 sensors, 10 cm apart, in descending and distal duodenum. The 1-h postprandial motility was quantitated as contraction frequency/minute, average amplitude, and motility index (MI). Six healthy volunteers served as controls. In the patient group, the HR-ADM identified postprandial antral hypomotility, isolated pyloric pressure waves, and tonic elevation of baseline pressure in pylorus. Patients had significantly reduced frequency of the full-hour postprandial antral contractions/minute compared with healthy volunteers [1.52 (0.97, 1.67) vs. 2.04 (1.70, 2.67), P = 0.005], as well as reduced MI [9.65 (8.29, 10.31) vs. 11.04 (10.65, 11.63), P = 0.002]. The average contraction amplitude was numerically, but not significantly reduced [51.9 (21.9, 74.9) vs. 73.0 (59.8, 82.7), P = 0.14]. Bland-Altman plots showed similar distribution of antral contraction frequency and MI during the first and second postprandial 30-min periods for both patients and controls. High-resolution ADM can characterize a variety of postprandial antral contractile and pyloric motility dysfunctions. This technique shows promise to provide guidance for the selection of optimal treatment of patients with gastroparesis.NEW & NOTEWORTHY Current selection of different treatments for patients with gastroparesis is empiric or based on trial and error, though pyloric distensibility and diameter may predict response to pyloric interventions. High-resolution antropyloroduodenal manometry (HR-ADM) can characterize a variety of postprandial antral contractile and pyloric motility dysfunctions in patients with suspected gastroparesis. HR-ADM shows promise to provide guidance for selection and individualization of treatments such as prokinetic agents or pyloric interventions for patients with gastroparesis based on documented pathophysiology.

ACG Clinical Guideline: Gastroparesis

Gastroparesis is characterized by symptoms suggesting retention of food in the stomach with objective evidence of delayed gastric emptying in the absence of mechanical obstruction in the gastric outflow. This condition is increasingly encountered in clinical practice. These guidelines summarize perspectives on the risk factors, diagnosis, and management of gastroparesis in adults (including dietary, pharmacological, device, and interventions directed at the pylorus), and they represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation process. When the evidence was not appropriate for Grading of Recommendations, Assessment, Development, and Evaluation, we used expert consensus to develop key concept statements. These guidelines should be considered as preferred but are not the only approaches to these conditions.

POEM, GPOEM, and ZPOEM

Our tripartite narrative review discusses Peroral Endoscopic Myotomy (POEM), gastric POEM (GPOEM) and POEM for Zenker's diverticula (ZPOEM). POEM is the prototypical procedure that launched the novel "3rd space endoscopy" field of advanced endoscopy. It revolutionized achalasia therapy by offering a much less invasive version of the prior gold standard, the laparoscopic Heller myotomy (HM). We review in detail indications, outcomes, technique variations and comparative data between POEM and HM particularly with regard to the hotly debated issue of GERD. We then proceed to discuss two less illustrious but nevertheless important offshoots of the iconic POEM procedure: GPOEM for gastroparesis and ZPOEM for the treatment of hypopharyngeal diverticula. For GPOEM, we discuss the rationale of pylorus-directed therapies, briefly touch on GPOEM technique variations and then focus on the importance of proper patient selection and emerging data in this area. On the third and final part of our review, we discuss ZPOEM and expound on technique variations including our "ultra-short tunnel technique". Our review emphasizes that, despite the superiority of endoscopy over surgery for the treatment of hypopharyngeal diverticula, there is no clear evidence yet of the superiority of the newfangled ZPOEM technique compared to the conventional endoscopic myotomy technique practiced for over two decades prior to the advent of ZPOEM.

Delayed gastric emptying as an independent predictor of mortality in gastroparesis

BACKGROUND

Whether gastroparesis is associated with a shortened life expectancy remains uncertain as no systematic study has evaluated the impact of gastroparesis on mortality, based on gastric emptying (GE) tests.

AIM

This study aimed to assess whether delayed GE was predictive of mortality.

METHODS

GE was measured using a 13C-octanoic acid breath test in 1563 consecutive patients. Delayed GE at baseline defined the gastroparesis group. Patients were followed up for a mean of 8.9 years, yielding 13 466 patients per year. Mortality was assessed using the French CepiDc database with data from local civil registries. The cause of death was determined from medical records. Mortality rates were assessed using the Kaplan-Meier method and hazard ratio (HR) was calculated using the Cox regression model.

RESULTS

Age and symptoms severity were not different among patients with normal GE (n = 1179) and with delayed GE (n = 384) while diabetes mellitus was more frequent in the gastroparesis group. Kaplan-Meier analysis showed increased mortality in the gastroparesis group compared to patients with normal GE. Cox regression model identified delayed GE as independently associated with increased mortality (HR = 1.63[1.09-2.42]; P = 0.02). Other independent factors associated with increased mortality included age, male sex, and diabetes. No difference was observed between groups for the cause of death, with cancer and cardiovascular disease being the leading causes.

CONCLUSION

This study has shown that gastroparesis, diagnosed on GE tests, was associated with increased mortality, independently of age, sex, BMI or diabetes status (NCT04918329).

AGA Clinical Practice Update on Management of Medically Refractory Gastroparesis: Expert Review

DESCRIPTION

Delayed gastric emptying on objective testing defines gastroparesis, but symptoms overlap with functional dyspepsia and do not correlate well with gastric emptying delay. This review outlines a strategy for defining, diagnosing, and managing refractory gastroparesis.

METHODS

The Best Practice Advice statements presented here were developed from review of existing literature combined with expert opinion to provide practical advice. Because this was not a systematic review, formal rating of the quality of evidence or strength of recommendations was not performed. BEST PRACTICE ADVICE.

Gastroparesis

PURPOSE OF REVIEW

This review highlights recent research advances regarding the pathophysiology and treatment of gastroparesis.

RECENT FINDINGS

Differences in brain activity have been identified on functional MRI imaging in gastroparesis patients with nausea. Abdominal pain is common in patients with gastroparesis and does not correlate with the severity of gastric emptying delay, though may be associated with depression and anxiety. Autonomic dysfunction may play an important role in the pathophysiology of gastroparesis. There is increasing sentiment that gastroparesis should be considered a part of the same spectrum of gastric neuromuscular disorders. The risk of tardive dyskinesia with metoclopramide has likely been significantly overestimated historically. Endoscopic BoTox injection of the pylorus and gastric electrical stimulation remain controversial treatments for gastroparesis. New, highly selective 5-hydroxytryptamine 4 (5-HT4) agonists appear safe and may be effective in improving symptoms of gastric emptying. Long-term data assessing the use of gastric peroral endoscopic myotomy (G-POEM) for the treatment of refractory gastroparesis suggest durable clinical improvement.

SUMMARY

Altered central processing and autonomic dysfunction may be important factors in the pathogenesis of gastroparesis. While the risk of tardive dyskinesia appears much lower than historically advertised, there is increasing hope for novel therapeutics with the advent of new 5-HT4 agonists, neurokinin-1 receptor (N1KR) antagonists, and G-POEM.

Efficacy and safety of gastric peroral endoscopic myotomy (G-POEM) for refractory gastroparesis: 3-year follow up results

BACKGROUND/PURPOSE

Gastroparesis is a common but easily overlooked disease. Gastric peroral endoscopic myotomy (G-POEM) is one of the third-space endoscopy techniques to treat gastroparesis. In this study, we aimed to evaluate the efficacy and safety of G-POEM for patients with refractory gastroparesis.

METHODS

Between December 2017 and 2020, we consecutively enrolled patients with gastroparesis who failed after the administration of several kinds of medication and repeated admission for nutritional support. All patients underwent gastric emptying scintigraphy and answered a questionnaire on Gastroparesis Cardinal Symptom Index (GCSI). Demographic data, endoscopic procedure, and post procedural outcome were analyzed.

RESULTS

A total of 11 (9 women and 2 men) patients with refractory gastroparesis (nine with diabetes mellitus, one systemic lupus erythematosus, and one idiopathic) were enrolled. The mean (±standard deviation (SD)) procedure time was 61.82 (±18.99) min with technical and clinical success rates of 100% and 81.82%, respectively. A statistically significant improvement was observed in the clinical severity (mean GCSI score 36.00 vs. 14.73, p < 0.0001) and gastric emptying time (mean T_1/2 341.92 vs. 65.92 min, p = 0.016) after G-POEM. Hospital stay was 7.18 (±4.49) days without mortality. Complications included 4 (36.36%) patients with self-limited postprocedural abdominal pain and 3 (27.27%) patients with intra-procedural pneumoperitoneum. During the mean follow-up period of 554.36 days, one (9.09%) patient had relapsed clinical symptoms after 6 months.

CONCLUSIONS

G-POEM is an efficient and safe pylorus-directed endoscopic therapy for refractory gastroparesis with promising results.

Pyloric dilation with the esophageal functional lumen imaging probe in gastroparesis improves gastric emptying, pyloric distensibility, and symptoms

BACKGROUND AND AIMS

The role of decreased pyloric distensibility in gastroparesis as measured by the endolumenal functional luminal imaging probe (EndoFLIP) has been receiving increasing attention. In this study, we present clinical outcomes to pyloric dilation with the esophageal FLIP (EsoFLIP) in regard to gastric emptying, symptom evolution, and FLIP metrics.

METHODS

Patients evaluated for gastroparesis (gastric emptying studies of t_1/2 ≥180 minutes during ¹³C-octanoic acid breath test and/or gastric remnants during gastroscopy after a sufficient fasting period) were scheduled for EsoFLIP controlled pyloric dilation. Pre- and postprocedural gastric emptying studies, questionnaires (Patient Assessment of Upper GI Symptoms Severity Index [PAGI-SYM; including the Gastroparesis Cardinal Symptom Index] and Patient Assessment of Quality of Life Index [PAGI-QOL]), and FLIP metrics were documented. Dilation was conducted according to a self-developed algorithm.

RESULTS

Forty-six patients were analyzed (72% women; median age, 39 years [range, 18-88]). Etiologies of gastroparesis were diabetic in 10 patients (22%), idiopathic in 33 (72%), and postoperative in 3 (6%). Postprocedural gastric emptying time decreased from a median of 211 minutes to 179 minutes (P = .001). In accordance, pyloric distensibility, PAGI-SYM, PAGI-QOL, and Gastroparesis Cardinal Symptom Index values improved significantly. After a median follow-up of 3.9 months, 57% of all treated patients with returned questionnaires reported improved symptoms.

CONCLUSIONS

Pyloric EsoFLIP controlled dilation shows value in the treatment of gastroparesis, both subjectively and objectively. Long-term follow-up to assess efficacy and comparative trials are warranted.

Pyloric distensibility in health and disease

Until recently, gastric motility measurements in humans were mostly limited to accommodation (using barostat or 3-dimensional imaging studies of gastric volume) and gastric emptying tests, the latter being the only one performed in routine clinical care. Accurate and easy to use techniques were lacking to assess pyloric function in health and disease. Recently, pyloric distensibility has been developed and validated to assess pyloric opening. Several studies confirmed that pyloric distensibility was decreased in gastroparesis and correlated with gastric emptying as well as gastroparesis symptoms. In addition, pyloric distensibility may predict outcome of endoscopic techniques targeting the pylorus, namely intrapyloric botulinum toxin injection and gastric per-oral pyloromyotomy. Pyloric distensibility appears therefore to be a promising and useful new tool in the workup of gastroparesis patients.

Assessment of pyloric sphincter distensibility and pressure in patients with diabetic gastroparesis

BACKGROUND

Recent studies have shown that pyloric distensibility is altered in 30-50% of gastroparetic patients but the number of diabetic patients included in prior reports has been small. The aim of the present study was to assess pyloric sphincter measurements in diabetic patients with gastroparesis and to determine whether diabetes characteristics were correlated to pyloric disfunction.

METHODS

Pyloric distensibility and pressure were measured using EndoFLIP^® system in 46 patients with diabetic gastroparesis (DGP) and compared with 21 healthy volunteers (HV), and 33 patients with idiopathic gastroparesis (IGP). Altered pyloric distensibility was defined as the measurement below 10 mm² /mmHg at 40 ml of inflation. In diabetic patients, blood glucose, glycated hemoglobin, duration, complications, and treatments were collected.

KEY RESULTS

Mean pyloric distensibility at 40 ml of inflation was lower in DGP and IGP groups with, respectively, 10.8 ± 0.9 mm² /mmHg and 14.8 ± 2.2 mm² /mmHg in comparison with the HV group (25.2 ± 2.3 mm² /mmHg; p < 0.005). 56.5% of patients had a decreased pyloric distensibility in the DGP group, 51.5% of patients in the IGP group, and 10% of patients in the HV group. No correlation was found between pyloric sphincter measurements and diabetes characteristics, including blood glucose, glycated hemoglobin, diabetes mellitus type, neuropathy, or GLP1 agonists intake.

CONCLUSION AND INTERFERENCES

Pyloric sphincter distensibility and pressure were altered both in diabetic and idiopathic gastroparesis. Pyloric sphincter distensibility was not correlated to diabetes parameters.

EndoFLIP and Pyloric Dilation for Gastroparesis Symptoms Refractory to Pyloromyotomy/Pyloroplasty

BACKGROUND

Gastroparesis patients may undergo pyloromyotomy/pyloroplasty for chronic refractory symptoms. However, some patients have persistent symptoms. It is unknown if balloon dilation may improve their symptoms.

AIMS

We aimed to (1) assess if pyloric through-the-scope (TTS) balloon dilation results in symptom improvement in gastroparesis patients with suboptimal response to pyloromyotomy/pyloroplasty and (2) determine endoscopic functional luminal imaging probe (EndoFLIP) characteristics of these patients before dilation.

METHODS

Patients with severe gastroparesis refractory to pyloromyotomy/pyloroplasty seen from 2/2019 to 3/2020 underwent pyloric TTS dilation after assessing the pyloric characteristics using EndoFLIP. Patients completed Gastroparesis Cardinal Symptom Index (GCSI) pre-procedurally, and GCSI and Clinical Patient Grading Assessment Scale (CPGAS) on follow-ups.

RESULTS

Thirteen (ten females) patients (mean age 45.2 ± 5.1 years) with severe gastroparesis symptoms (mean GCSI total score 3.4 ± 0.3) after pyloromyotomy/pyloroplasty underwent pyloric TTS dilation. Overall, there was improvement in symptoms at 1-month follow-up (mean GCSI total score 3.0 ± 0.4, mean CPGAS score 1.6 ± 0.5, p < 0.05 for both), with five (38%) patients reporting symptoms somewhat/moderately better. The patients with symptom improvement had lower pre-dilation pyloric EndoFLIP distensibility at 30 ml, 40 ml, and 50 ml than patients with little/no improvement (all p < 0.05).

CONCLUSIONS

In gastroparesis patients with refractory symptoms after pyloromyotomy/pyloroplasty, pyloric TTS dilation improved symptoms in about a third of the patients. Patients with symptom improvement had lower pre-dilation pyloric distensibility on EndoFLIP suggesting incomplete myotomy, pyloric muscle regeneration, or pyloric stricture. Pyloric EndoFLIP followed by TTS dilation seems to be a promising treatment for some patients with gastroparesis symptoms refractory to pyloromyotomy/pyloroplasty.

Nausea and Vomiting in 2021: A Comprehensive Update

GOAL

A comprehensive review of treatments for nausea and vomiting (N/V).

BACKGROUND

N/V are common symptoms encountered in medicine. While most cases of acute N/V related to a specific cause can be straightforward to manage, other cases of acute N/V such as chemotherapy-induced N/V and especially chronic unexplained N/V can be difficult to control, leading to a significant decline in the patient's quality of life and increased cost of medical care from repeated hospitalizations.

STUDY

Traditional management has relied on pharmacotherapy which may be inadequate in a certain proportion of these patients. Many of the medications used in the management of N/V have significant side effect profiles making the need for new and improved interventions of great importance.

RESULTS

This review covers a broad review of the pathophysiology of N/V, pharmacotherapy, including safety concerns and controversies with established pharmaceuticals, newer immunotherapies, bioelectrical neuromodulation (including gastric electrical stimulation), behavioral and surgical therapies, and complementary medicine.

CONCLUSION

On the basis of emerging understandings of the pathophysiology of N/V, improved therapies are becoming available.

Targeting Treatment of Gastroparesis: Use of Clinical Tests to Guide Treatments

Gastroparesis presents with nausea, vomiting, and other upper gut symptoms, and is diagnosed by confirming delayed gastric emptying. A related condition, chronic unexplained nausea and vomiting, has similar symptoms but with normal emptying. Both conditions are managed using therapies with diverse mechanisms of action. Even though prokinetic treatments are proposed to improve gastroparesis by accelerating gastric emptying, there is limited evidence that they provide benefit by virtue of transit stimulating effects. Other tests can delineate alterations in other gut sensorimotor parameters in patients with suspected gastroparesis, but their relation to symptoms and their capability to guide treatment are largely unproved.

Esophageal Functional Lumen Imaging Probe (FLIP): How Can FLIP Enhance Your Clinical Practice?

Recent innovations in esophageal diagnostic testing have enhanced gastroenterology clinical practice by facilitating more nuanced and advanced evaluation of esophageal symptoms. Among these pivotal advances is the FDA-approved functional lumen imaging probe (FLIP), which utilizes impedance planimetry via volumetric distension of a catheter-mounted balloon at the time of sedated upper endoscopy, to acquire esophageal dimensions and pressures. In real time, FLIP can display cross-sectional areas (CSA) and distensibility indices (ratios of CSA to intra-balloon pressures) throughout the esophagus, most notably at the esophagogastric junction, as well as secondary peristaltic esophageal body contractile patterns. As the use of FLIP has progressively spread and permeated into the practice of clinical gastroenterology since its introduction, increasing data on and experiences with its applications have accumulated to guide its utility in clinical practice. In this current review developed for gastroenterologists and foregut surgeons across clinical practice, we provide an introduction to FLIP technology and metrics and discuss the clinical scenarios in which performance of or referral for FLIP may be helpful in the evaluation and management of patients with commonly encountered esophageal symptoms and disorders. Specifically, we discuss the potential applications and limitations of FLIP as a complementary diagnostic modality in patients with non-obstructive dysphagia, established or suspected achalasia spectrum disorders, eosinophilic esophagitis, gastroesophageal reflux disease and those undergoing esophageal surgery.

The use of impedance planimetry (Endoscopic Functional Lumen Imaging Probe, EndoFLIP® ) in the gastrointestinal tract: A systematic review

BACKGROUND AND PURPOSE

The EndoFLIP® system is a method of delineating impedance and was first designed to investigate the characteristics of the esophago-gastric junction. In the last decade, its use was widened to investigate other sphincteric and non-sphincteric systems of the gastrointestinal tract. The objective of the present systematic review was to summarize the available data in literature on the use of the EndoFLIP® system in the gastrointestinal tract, including sphincteric and non-sphincteric regions. We performed a systematic review in accordance with recommendations for systematic review using PRISMA guidelines without date restriction, until June 2020, using MEDLINE-PubMed, Cochrane Library, and Google Scholar databases. Only articles written in English were included in the present review. Five hundred and six unique citations were identified from all database combined. Of those, 95 met the inclusion criteria. There was a lack of standardization among studies in terms of anesthetic drugs use, probe placement, and inflation protocol. In most cases, only small cohorts of patients were included. Most studies investigated the EGJ, with a potential use of the EndoFLIP® to identify a subgroup of patients with achalasia and for intraoperative assessment of treatment efficacy in achalasia. However, the use of EndoFLIP® in the esophageal body (esophageal panometry), other esophageal diseases (gastro-esophageal reflux disease, eosinophilic esophagitis), and other sphincter regions (anal canal, pylorus) will need further confirmatory studies. The EndoFLIP® system provides detailed geometric data of the gastrointestinal lumen but further works are needed to determine its use in clinical practice.

Role of endoscopic functional luminal imaging probe in predicting the outcome of gastric peroral endoscopic pyloromyotomy (with video)

BACKGROUND AND AIMS

Endoluminal functional luminal imaging probe (EndoFLIP) is an imaging tool that measures the physiologic characteristics of GI sphincters. In this study, we used EndoFLIP to evaluate the association between the pyloric physiologic measurements and the clinical outcomes of gastric peroral endoscopic myotomy (G-POEM) in patients with refractory gastroparesis.

METHODS

Thirty-seven patients from 5 centers who underwent G-POEM for management of refractory gastroparesis and had EndoFLIP measurements were evaluated. Cross-sectional area (CSA), balloon pressure, and the distensibility index (DI) of the pylorus were evaluated by EndoFLIP at 40 mL and 50 mL balloon fills before and after G-POEM. One-year clinical success and change in gastric emptying study 3 months after the G-POEM procedure were compared with the EndoFLIP measurements.

RESULTS

Clinical success was achieved in 26 (70%) patients. Post-G-POEM CSA and DI were significantly higher in the clinical success group with both 40-mL volume distension (CSA: 89.9 ± 64.8 vs 172.5 ± 71.9 mm², P =.003; DI: 5.8 ± 4.4 vs 8.8 ± 6.1 mm²/mm Hg, P =.043) and 50-mL volume distention (CSA: 140.1 ± 89.9 vs 237.5 ± 80.3 mm², P =.003; DI: 5.6 ± 3.3 vs 9.9 ± 6.6 mm²/mm Hg, P =.049). CSA using 40-mL volume distention with an area under the curve of 0.83 yielded a specificity of 91% and a sensitivity of 71% at a cutoff point of 154 mm².

CONCLUSIONS

Post-G-POEM CSA of the pylorus is associated with clinical success and improvement in a gastric emptying scan after G-POEM. EndoFLIP measurements of the pylorus have the potential to be used as a tool to predict the clinical outcome of G-POEM.

Pyloric distensibility measurement after gastric surgery: Which surgeries are associated with pylorospasm?

BACKGROUND AND STUDY AIMS

History of gastric surgery is found in 10% of patients with gastroparesis, and vagal lesion is often suspected to be the cause of pylorospasm. Recently, pyloric distensibility measurement using the EndoFLIP^® system showed that pylorospasm was present in 30%-50% of gastroparetic patients. Our objective was to assess whether pylorospasm, diagnosed using EndoFLIP^® system was observed in three different types of gastric surgeries: antireflux surgery, sleeve gastrectomy, and esophagectomy.

PATIENTS AND METHODS

Pyloric distensibility and pressure were measured using the EndoFLIP^® system in 43 patients from two centers (18 antireflux surgery, 16 sleeve gastrectomy, and nine esophagectomy) with dyspeptic symptoms after gastric surgery, and in 21 healthy volunteers. Altered pyloric distensibility was defined as distensibility below 10 mm² /mm Hg as previously reported.

RESULTS

Compared to healthy volunteers (distensibility: 25.2 ± 2.4 mm² /mm Hg; pressure: 9.7 ± 4.4 mm Hg), pyloric distensibility was decreased in 61.1% of patients in the antireflux surgery group (14.5 ± 3.4 mm² /mm Hg; P < .01) and 75.0% of patients in the esophagectomy group (10.8 ± 2.1 mm² /mm Hg; P < .05), while pyloric pressure was only increased in the antireflux surgery group (18.9 ± 2.2 mm Hg; P < .01). Pyloric distensibility and pressure were similar in healthy volunteers and in sleeve gastrectomy (distensibility: 20.3 ± 3.8 mm² /mm Hg; pressure: 15.8 ± 1.6 mm Hg) groups, with decreased pyloric distensibility affecting 18.7% of sleeve gastrectomy patients.

CONCLUSION

Antireflux surgery and esophagectomy were associated with pylorospasm although pylorospasm was not found in all patients. Sleeve gastrectomy was not associated with altered pyloric distensibility nor altered pyloric pressure.