Third space endoscopy: the future of treating gastrointestinal dysmotility

Per oral endoscopic myotomy for achalasia

Achalasia, characterized by impaired lower esophageal sphincter (LES) relaxation and failed peristalsis, stands out as the most widely recognized primary esophageal motility disorder. It manifests with dysphagia to solid and liquid foods, chest pain, regurgitation, and weight loss, leading to significant morbidity and healthcare burden. Traditionally, surgical Heller myotomy and pneumatic dilation were the primary therapeutic approaches for achalasia. However, in 2009, Inoue and colleagues introduced a groundbreaking endoscopic technique called peroral endoscopic myotomy (POEM), revolutionizing the management of this condition. This review aims to comprehensively examine the recent advancements in the POEM technique for patients diagnosed with achalasia, delving into critical aspects, such as the tailoring of the myotomy, the prevention of intraprocedural adverse events (AEs), the evaluation of long-term outcomes, and the feasibility of retreatment in cases of therapeutic failure.

Single-Versus Multiple-Dose Antimicrobial Prophylaxis in Peroral Endoscopic Myotomy: A Randomized Controlled Study (SMAPP Trial)

Infections are uncommon after peroral endoscopic myotomy (POEM) procedure. However, prophylactic antibiotics are routinely administered for variable duration during peri-operative period. In this study, we aimed to determine the difference in the rate of infections between single (SD-A) and multiple doses (MD-A) antibiotic prophylaxis groups. The study was a prospective, randomized, non-inferiority trial conducted at a single tertiary care centre from Dec 2018 to Feb 2020. Eligible patients undergoing POEM were randomized into SD-A and MD-A groups. SD-A group received one dose of antibiotic (IIIrd gen cephalosporin) within 30-min of POEM. In the MD-A group, the same antibiotic was administered for a total of three days. Primary aim of the study was to determine the incidence of infections in the two groups. Secondary outcomes included incidence of fever (> 100 °F), inflammatory markers [erythrocyte sedimentation rate (ESR), c-reactive protein(CRP)], serum procalcitonin and adverse events related to antibiotics. (NCT03784365). 114 patients were randomized to SD-A (57) and MD-A (57) antibiotic groups. Mean post-POEM CRP (0.8 ± 0.9 vs 1.5 ± 1.6), ESR (15.8 ± 7.8 20.6 ± 11.7) and procalcitonin (0.05 ± 0.04 0.29 ± 0.58) were significantly higher after POEM (p = 0.001). Post-POEM inflammatory markers (ESR, CRP and procalcitonin) were similar in both the groups. Fever on day-0 (10.5% vs 14%) and day-1 (1.7% vs 3.5%) was detected in similar proportion of patients. Post-POEM infections were recorded in 3.5% (1.7% vs 5.3%, p = 0.618). Single dose of antibiotic is non-inferior to multiple dose antibiotic prophylaxis. Elevation of inflammatory markers and fever after POEM represents inflammation and does not predict infection after POEM.

Submucosal endoscopy: the present and future

Submucosal endoscopy or third-space endoscopy utilizes the potential space between the mucosal and muscularis layers of the gastrointestinal tract to execute therapeutic interventions for various diseases. Over the last decade, endoscopic access to the submucosal space has revolutionized the field of therapeutic endoscopy. Submucosal endoscopy was originally used to perform endoscopic myotomy in patients with achalasia cardia, and its use has grown exponentially since. Currently, submucosal endoscopy is widely used to resect subepithelial tumors and to manage refractory gastroparesis and Zenker's diverticulum. While the utility of submucosal endoscopy has stood the test of time in esophageal motility disorders and subepithelial tumors, its durability remains to be established in conditions such as Zenker's diverticulum and refractory gastroparesis. Other emerging indications for submucosal endoscopy include esophageal epiphrenic diverticulum, Hirschsprung's disease, and esophageal strictures not amenable to conventional endoscopic treatment. The potential of submucosal endoscopy to provide easy and safe access to the mediastinum and peritoneal spaces may open doors to novel indications and rejuvenate the interest of endoscopists in natural orifice transluminal endoscopic surgery in the future. This review focuses on the current spectrum, recent updates, and future direction of submucosal endoscopy in the gastrointestinal tract.

Impact of modified techniques on outcomes of peroral endoscopic myotomy: A narrative review

Peroral endoscopic myotomy (POEM) is an established frontline treatment modality for achalasia cardia. Since its initial description, several modifications have been proposed to the technique of POEM. Broadly speaking, these modifications follow the basic principles of submucosal endoscopy, but incorporate variations in the POEM technique, including the difference in the orientation of myotomy (anterior or posterior), length of myotomy (short or long), and thickness of myotomy (selective circular or full thickness). Some of these modifications have been shown to reduce procedural duration without compromising the efficacy of the POEM procedure. More recently, several alterations have been reported that intend to reduce gastroesophageal reflux after POEM. These include preservation of sling fibers during posterior POEM and addition of NOTES fundoplication to the POEM procedure. Although some of the modified techniques have been compared with the conventional techniques in quality trials, randomized studies are awaited for others. The incorporation of some of these modifications will likely make POEM a technically easy and safer modality in near future. This review aims to discuss the current evidence with regard to the impact of modified techniques on the outcome of POEM.

New Kid on the Block: “Speedboat”

Innovations in devices and techniques have parallelly propelled the field of therapeutic endoscopy in gastrointestinal tract. With the development of endoscopic resection techniques and the availability of newly designed electrosurgical knives, the minimally invasive management of early gastrointestinal neoplasms has revolutionized. The currently available electrosurgical knives are monopolar devices, not equipped with injection needle and required to be exchanged with coagulation forceps for hemostasis. Monopolar electrosurgical devices require higher voltages with associated risks. A recent innovation in the field of endoscopic knives is a new device called “Speedboat” device, specially designed for use in endoscopic dissection procedures. This is a bipolar device that utilizes radio frequency energy for cutting and microwave energy for achieving hemostasis. Speedboat device possesses hemostasis capability and has an integrated injection needle that imparts an “all-in-one” quality to this device. Preliminary data suggest the safety and utility of this device in performing a variety of endoscopic dissection and resection procedures including endoscopic submucosal dissection, per-oral endoscopic myotomy, and resection of subepithelial tumors.