AGA Clinical Practice Update on Appropriate and Tailored Polypectomy: Expert Review.

DESCRIPTION: In this Clinical Practice Update (CPU), we provide guidance on the appropriate use of different polypectomy techniques. We focus on polyps <2 cm in size that are most commonly encountered by the practicing endoscopist, including use of classification systems to characterize polyps and various polypectomy methods. We review characteristics of polyps that require complex polypectomy techniques and provide guidance on which types of polyps require more advanced management by a therapeutic endoscopist or surgeon. This CPU does not provide a detailed review of complex polypectomy techniques, such as endoscopic submucosal dissection, which should only be performed by endoscopists with advanced training. METHODS: This expert review was commissioned and approved by the American Gastroenterological Association (AGA) Institute CPU Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the CPU Committee and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. These Best Practice Advice statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these Best Practice Advice statements do not carry formal ratings regarding the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: A structured visual assessment using high-definition white light and/or electronic chromoendoscopy and with photodocumentation should be conducted for all polyps found during routine colonoscopy. Closely inspect colorectal polyps for features of submucosally invasive cancer. BEST PRACTICE ADVICE 2: Use cold snare polypectomy for polyps <10 mm in size. Cold forceps polypectomy can alternatively be used for 1- to 3-mm polyps where cold snare polypectomy is technically difficult. BEST PRACTICE ADVICE 3: Do not use hot forceps polypectomy. BEST PRACTICE ADVICE 4: Clinicians should be familiar with various techniques, such as cold and hot snare polypectomy and endoscopic mucosal resection, to ensure effective, safe, and optimal resection of intermediate-size polyps (10-19 mm). BEST PRACTICE ADVICE 5: Consider using lifting agents or underwater endoscopic mucosal resection for removal of sessile polyps 10-19 mm in size. BEST PRACTICE ADVICE 6: Serrated polyps should be resected using cold resection techniques. Submucosal injection may be helpful for polyps >10 mm if margins cannot be well delineated. BEST PRACTICE ADVICE 7: Use hot snare polypectomy to remove pedunculated lesions >10 mm in size. BEST PRACTICE ADVICE 8: Do not routinely use clips to close resection sites for polyps <20 mm. BEST PRACTICE ADVICE 9: Refer patients with polyps to endoscopic referral centers in the context of size ≥20 mm, challenging polypectomy location, or recurrent polyp at a prior polypectomy site. BEST PRACTICE ADVICE 10: Tattoo lesions that may need future localization at endoscopy or surgery. Tattoos should be placed in a location that will not interfere with subsequent attempts at endoscopic resection. BEST PRACTICE ADVICE 11: Refer patients with nonpedunculated polyps with clear evidence of submucosally invasive cancer for surgical evaluation. BEST PRACTICE ADVICE 12: Understand the endoscopy suite's electrosurgical generator settings appropriate for polypectomy or postpolypectomy thermal techniques.

Endoscopic devices and techniques for the management of gastric varices (with videos).

BACKGROUND AND AIMS: Gastric variceal bleeding occurs less commonly than bleeding from esophageal varices (EVs), although it is associated with higher morbidity and mortality. Bleeding from gastroesophageal varices type 1 (GOV1) is treated like EVs. In contrast, other forms of gastric variceal bleeding, including gastroesophageal varices type 2 (GOV2) and isolated gastric varices types 1 (IGV1) and 2 (IGV2), are treated with varying endoscopic approaches. Nonendoscopic methods include transjugular intrahepatic portosystemic shunt (TIPS) or balloon-occluded retrograde transvenous obliteration (BRTO). This technology report focuses on endoscopic management of gastric varices (GVs). METHODS: The MEDLINE database was searched through August 2022 for relevant articles by using key words such as gastric varices, glue, cyanoacrylate, thrombin, sclerosing agents, band ligation, topical hemostatic spray, coils, EUS, TIPS, and BRTO. The article was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy (ASGE) Technology Committee and approved by the Governing Board of the ASGE. RESULTS: Endoscopic injection with cyanoacrylate (CYA) glue has been the primary endoscopic method to treat GVs. EUS-guided angiotherapy with CYA glue and coil embolization has emerged as an alternative method enabling improved detection of GVs with a high technical success for targeting and obliterating GVs. Combining CYA glue with coil therapy allows the coil to act as a scaffold for the glue, reducing the risk of glue embolization and improving outcomes. Alternative injectates or topical treatments have been described but remain poorly studied. CONCLUSIONS: The mainstay paradigm for the endoscopic management of gastric variceal bleeding is the injection of CYA glue. The published success of EUS-guided angiotherapy using CYA glue with or without embolization coils has increased our treatment armamentarium.

Submucosal injection fluid and tattoo agents.

BACKGROUND AND AIMS: EMR and endoscopic submucosal dissection (ESD) are minimally invasive endoscopic techniques, developed for the removal of benign and early malignant lesions throughout the GI tract. Submucosal injection of a marking agent can help to identify lesions during surgery. Endoscopic resection frequently involves "lifting" of the lesions by injection of a substance within the submucosal space to create a cushion for safe resection. This review summarizes the current techniques and agents available for endoscopic marking and lifting of GI tract lesions. METHODS: The MEDLINE database was searched through April 2023 for relevant articles related to the lifting and marking aspect of EMR by using key words such as "endoscopy" or "endoscopic" combined with "marking," "tattoo," and "lifting." The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy. RESULTS: This technology review describes the techniques for endoscopic tattoo placement and submucosal lifting, along with currently available agents, safety, and costs. CONCLUSIONS: Endoscopists performing EMR and ESD have several choices in submucosal injection materials for lifting and marking agents for tattoos. These may be commercially prepared agents or off-the-shelf materials with or without additives to facilitate visualization. A thorough understanding of the indications, techniques, properties of various agents, costs, and adverse events is necessary in choosing the appropriate materials and technique to optimize lesion resection in EMR and ESD.

Endoscopic therapies for gallbladder drainage.

BACKGROUND AND AIMS: Endoscopic management of acute cholecystitis has expanded in patients who are considered nonoperative candidates. Traditionally managed with percutaneous cholecystostomy (PC), improvement in techniques and devices has led to increased use of endoscopic methods for gallbladder drainage. This document reviews technical aspects of endoscopic transpapillary gallbladder drainage (ET-GBD) and EUS-guided GBD (EUS-GBD) as well as their respective technical/clinical success and adverse event rates. Available comparative data are also reviewed among nonsurgical gallbladder drainage techniques (PC, ET-GBD, and EUS-GBD). METHODS: The MEDLINE database was searched through March 2021 for relevant articles by using keywords including "acute cholecystitis," "interventional EUS," "percutaneous cholecystostomy," "transpapillary gallbladder drainage," "EUS-guided gallbladder drainage," "lumen-apposing metal stent," "gallbladder stenting," and "endoscopic gallbladder drainage." The manuscript was drafted by 2 authors and reviewed by members of the American Society for Gastrointestinal Endoscopy Technology Committee and subsequently by the American Society for Gastrointestinal Endoscopy Governing Board. RESULTS: Multiple studies have demonstrated acceptable outcomes comparing PC and both endoscopic gallbladder drainage techniques, ET-GBD and EUS-GBD. Published data suggest that endoscopic gallbladder drainage techniques may be associated with lower rates of adverse events and improved quality of life. However, there are important clinical considerations for choosing among these treatment options, requiring a multidisciplinary and collaborative approach to therapeutic decision-making in these patients. CONCLUSIONS: The implementation of EUS-GBD and ET-GBD in high-risk surgical patients with acute cholecystitis may result in favorable outcomes when compared with PC. Further improvements in techniques and training should lead to more widespread acceptance and dissemination of these treatment options.

Lumen-apposing metal stents (with videos).

BACKGROUND AND AIMS: Lumen-apposing metal stents (LAMSs) are a novel class of devices that have expanded the spectrum of endoscopic GI interventions. LAMSs with their dumbbell configuration, short saddle length, and large inner luminal diameter provide favorable stent characteristics to facilitate anastomosis formation between the gut lumen and adjacent structures. METHODS: The MEDLINE database was searched through April 2021 for articles related to LAMSs by using additional relevant keywords such as "walled-off pancreatic necrosis," "pseudocysts," "pancreatic fluid collection," "cholecystitis," "gastroenterostomy," in addition to "endoscopic treatment" and "endoscopic management," among others. RESULTS: This technology review describes the full spectrum of LAMS designs and delivery systems, techniques for deployment, procedural outcomes, safety, training issues, and financial considerations. CONCLUSIONS: Although LAMSs were initially introduced for drainage of pancreatic pseudocysts and walled-off necrosis, the versatility of these devices has led to a variety of off-label uses including gallbladder drainage, enteric bypass with the creation of gastroenterostomies, and treatment of luminal GI strictures.

The Esophageal Microbiome in Health and Disease.

PURPOSE OF REVIEW: Investigation of the esophageal microbiome is a relatively new field. This review will outline data characterizing the esophageal microbiome in both health and disease states, including gastroesophageal reflux disease (GERD), Barrett's esophagus, esophageal cancer, eosinophilic esophagitis, and motility disorders. RECENT FINDINGS: While the esophagus was previously considered devoid of a significant bacterial population, development of culture-independent techniques, specifically 16S rRNA gene sequencing, as well as novel, minimally invasive microbial sampling modalities, has facilitated characterization of the esophageal microbiome in both health and several disease states. Although limited, there is evidence that the esophagus contains a diverse microbial population, with Gram-positive bacteria, specifically Streptococcus, dominating in health, while Gram-negative bacteria prevail in reflux disorders including GERD and Barrett's esophagus. The microbiome is altered with other esophageal disorders as well, including eosinophilic esophagitis and esophageal motility disorders, though these changes have been less well characterized. Characterization of the gut microbiome has advanced significantly; however, further investigation is essential. Understanding changes in the esophageal microbiome could affect our understanding of the natural history of diseases of the esophagus and present potential therapeutic approaches.

Devices for esophageal function testing.

BACKGROUND AND AIMS: Esophageal function testing is an integral component of the evaluation of refractory GERD and esophageal motility disorders. This review summarizes the current technologies available for esophageal function testing, including the functional luminal imaging probe (FLIP), high-resolution esophageal manometry (HRM), and multichannel intraluminal impedance (MII) and pH monitoring. METHODS: We performed a MEDLINE, PubMed, and MAUDE database literature search to identify pertinent clinical studies through March 2021 using the following key words: esophageal manometry, HRM, esophageal impedance, FLIP, MII, and esophageal pH testing. Technical data were gathered from traditional and web-based publications, proprietary publications, and informal communications with pertinent vendors. The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy. RESULTS: FLIP is a high-resolution impedance planimetry system used for pressure and dimension measurement in the esophagus, pylorus, and anal sphincter. FLIP provides complementary information to HRM for esophageal motility disorders, especially achalasia. The Chicago classification, based on HRM data, is a widely adopted algorithmic scheme used to diagnose esophageal motility disorders. MII detects intraluminal bolus movement and, combined with pH measurement or manometry, provides information on acid and non-acid gastroesophageal reflux and bolus transit in patients with refractory GERD and for preoperative evaluation for anti-reflux procedures. CONCLUSIONS: Esophageal function testing techniques (FLIP, HRM, and MII-pH) have diagnostic and prognostic value in the evaluation of esophageal motility disorders and refractory GERD. Newer technologies and classification systems have enabled an increased understanding of these diseases.

A comparison of CMV detection in gastrointestinal mucosal biopsies using immunohistochemistry and PCR performed on formalin-fixed, paraffin-embedded tissue.

Cytomegalovirus (CMV) can precipitate and exacerbate gastrointestinal (GI) mucosal injury. The gold standard for CMV detection in formalin-fixed, paraffin-embedded (FFPE) tissue is immunohistochemistry (IHC). Although CMV polymerase chain reaction (PCR) on fresh tissue may be a valuable adjunct to IHC, its utility is unknown for FFPE tissues. We therefore evaluated quantitative, real-time CMV PCR in a total of 102 FFPE GI biopsy specimens from 74 patients with a history of hematopoietic stem cell or solid organ transplant, inflammatory bowel disease, human immunodeficiency virus infection, or unspecified colitis. CMV DNA was detected by PCR in 90.9% (30/33) of IHC-positive, 14.5% (8/55) of IHC-negative, and 20.0% (1/5) of IHC-equivocal FFPE tissues. Quantitation of CMV DNA copies normalized to ß-globin demonstrated a wide range of values (median 0.276; range, 0.0004 to 144.50). Importantly, 93.3% (14/15) of patients with IHC-positive, active colitis showed no evidence of CMV in matched concurrent, histologically normal biopsies tested by PCR. These results suggest that CMV PCR on FFPE GI biopsies complements IHC and has the potential to identify additional patients who may benefit from anti-CMV therapy.

Flash mob research: a single-day, multicenter, resident-directed study of respiratory rate.

BACKGROUND: Vital signs are critical data in the care of hospitalized patients, but the accuracy with which respiratory rates are recorded in this population remains uncertain. We used a novel flash mob research approach to evaluate the accuracy of recorded respiratory rates in inpatients. METHODS: This was a single-day, resident-led, prospective observational study of recorded vs directly observed vital signs in nonventilated patients not in the ICU on internal medicine teaching services at six large tertiary-care centers across the United States. RESULTS: Among the 368 inpatients included, the median respiratory rate was 16 breaths/min for the directly observed values and 18 breaths/min for the recorded values, with a median difference of 2 breaths/min (P < .001). Respiratory rates of 18 or 20 breaths/min accounted for 71.8% (95% CI, 67.1%-76.4%) of the recorded values compared with 13.0% (95% CI, 9.5%-16.5%) of the directly observed measurements. For individual patients, there was less agreement between the recorded and the directly observed respiratory rate compared with pulse rate. CONCLUSIONS: Among hospitalized patients across the United States, recorded respiratory rates are higher than directly observed measurements and are significantly more likely to be 18 or 20 breaths/min.