Mihai Ciocirlan

The ENKI-2 water-jet system versus Dual Knife for endoscopic submucosal dissection of colorectal lesions: a randomized comparative animal study

BACKGROUND AND STUDY AIMS The ENKI-2 water-jet system for endoscopic submucosal dissection (ESD) combines submucosal saline pressure injection with dissection. The aim of this study was to compare ENKI-2 with a standard device in terms of procedure time and perforation rate during colorectal ESD. METHODS In this randomized comparative study, 10 30-mm-diameter lesions were created in the colon and rectum of 10 healthy adult pigs. The ESD procedure time and perforation rates were recorded for the ENKI-2 system and a standard Dual Knife method. Each pig had half the lesions dissected by ENKI-2 and half dissected by Dual Knife. One experienced and one inexperienced endoscopist took part in the study. RESULTS A total of 95 lesions were dissected (47 by ENKI-2 and 48 by Dual Knife). The experienced endoscopist was able to excise comparably sized 30-mm lesions using both techniques. The dissection time was shorter for ENKI-2 (18.9 vs. 25.6 minutes; P = 0.034) and the perforation rate was lower compared with the Dual Knife (one perforation [4 %] vs. nine perforations [36 %]; P = 0.011). The inexperienced endoscopist performed significantly larger dissections using the ENKI-2 (934 ± 405 mm2 vs. 673 ± 312 mm2; P = 0.021) despite pre-marking similarly sized artificial lesions. Multivariate analysis demonstrated that for all lesions the dissection time was significantly longer for lesions in the proximal colon (P = 0.001) and the distal colon (P < 0.0001) and shorter for the experienced operator (P < 0.0001). ENKI-2 shortened the dissection time, but not significantly (P = 0.093). CONCLUSIONS In experienced hands, the ENKI-2 system shortens dissection time and reduces the perforation rate. This effect was not statistically significant for an inexperienced operator. Dissection was faster in the rectum than the colon.

Treatment of arteriovenous malformation of the pancreas: a case report.

Pancreatic arteriovenous malformation (AVM) is a rare disease, generally asymptomatic, but sometimes complicated by gastrointestinal bleeding or pancreatitis. We report a case of a 55-year-old man presenting with a large pancreatic AVM. The diagnosis was obtained on a computed tomography scan. A treatment by transarterial embolization was carried out successfully. Selective arterial embolization of pancreatic AVM can represent an effective treatment in the first intention.

High pressure jet injection of viscous solutions for endoscopic submucosal dissection (ESD): first clinical experience

Background: Long lasting elevation is a key factor during endoscopic submucosal dissection (ESD) and can be obtained by water jet injection of saline solution or by viscous macromolecular solutions. In a previous animal study, we assessed the Nestis Enki II system to combine jet injection and viscous solutions. In the present work, we used this combination in humans in different sites of the digestive tract. Methods: We retrospectively report all of the consecutive ESD procedures performed with jet injection of viscous solutions in four centers. Information was collected about the lesion, the procedure, the histological result, and the outcomes for the patient. Results: In total, 45 resections were completed by six operators: five experts and one beginner with only one previous experience in human ESD. Lesions were located in the esophagus (10), the stomach (11), the duodenum (1), the colon (1) and the rectum (22). Average maximal lesion diameter was 4.8 cm (SD 2.4, range 2 – 11 cm), average lesion surface area was 19.8 cm2 (SD 17.7, range 2.2 – 72 cm2), and average duration of procedure was 79.9 min (SD 50.3 min, range 19 – 225 min). ESD could be conducted while the endoscope was retroflexed at its maximum in 26 cases. Four adverse events were observed: two diminutive perforations and two delayed bleeding occurrences treated conservatively. The R0 resection rate was 91.1 %. The catheter was obstructed in six occurrences of bleeding. Conclusion: Endoscopic submucosal dissection using high pressure injection of viscous macromolecular solutions is safe and effective in different parts of the digestive tract. It does not impede working with the endoscope in the maximal retroflexed position.

Ectopic pancreas mimicking gastrointestinal stromal tumor in the stomach fundus

Ectopic or heterotopic pancreas refers to healthy pancreatic tissue that lacks anatomical, vascular or neural communication with the normal pancreas. However, heterotopic pancreas is seldom considered as a diagnostic hypothesis when symptomatic or when located outside of the gastric antral wall [1]. This case report describes the clinical and paraclinical features of pancreatic heterotopia in the gastric fundus in a previously healthy 25-year-old woman. Initially, a gastrointestinal stromal tumor (GIST) was highly suspected because of its endoscopic (location and shape; ▶Video1), endoscopic ultrasound (emerging layer; ▶Fig. 1, ▶Fig. 2), and computed tomography characteristics; however, the histopathological evaluation revealed pancreatic heterotopia (▶Fig. 3). Although the patient was asymptomatic, we opted for surgical treatment because of the large size of the lesion, the atypical location in a highly vascularized part of the stomach, and the patient’s young age. On postsurgical follow-up, only a small granuloma was found on the suture site, even though the surgery was not curative (R1 with remaining pancreatic tissue on one margin of the resection specimen) (▶Fig. 4). We emphasize the unusual location of the pancreatic heterotopia (gastric fundus – despite up to 95% of cases being found in the antral location), and the layer from which the tissue developed (muscularis propria – which is seen in only 17% of cases) [2]. Moreover, we emphasize the difficulty in making an accurate diagnosis, which can only be obtained after surgery, and the need for regular postoperative follow-up to assess for remaining pancreatic rests, as some studies have shown up to 12.7% malignant transformation in pancreatic rests [3]. Despite the fact that ectopic pancreas is a rare condition, one must consider the differential diagnosis of extramucosal gastric lesions. Even though endoscopic Video 1 Endoscopic appearence of a submucosal lesion, with central ulceration, in the gastric fundus. Narrow-band imagining revealed regular microvascular and surface patterns, except for the central zone, which had irregular surface and vascular patterns.

Endoscopic screening for Barrett’s esophagus: while we’re in, do we also need to see the stomach and the duodenum?

team of Dr. Iyer Prasad published a comparative quality assessment of the endoscopy videos recorded in their previous published work on Barrett esophagus screening [1, 2]. Their initial work compared the yield of 2 different endoscopic examinations: unsedated transnasal esophagoscopy (uTNE) and sedated esophago-gastro-duodenoscopy (sEGD). In uTNE, the tube is covered with a single-use plastic sheath that makes sterilization between procedures unnecessary (Endosheath, TNE-5000, Vision Sciences, Orangeburg, NY, USA). The endoscope’s sheath has an outer parallel biopsy channel made from the same material. Due to its short length, it can only examine the esophagus. In sEGD, a standard highdefinition 9.8-m endoscope (GIF-180, Olympus America, Center Valley, PA, USA) is used. Transnasal esophagoscopy (TNE) was used both in hospital (huTNE) and in a community setting through a specially designed mobile research vehicle (muTNE). Esophago-gastroduodenoscopy (EGD) was used in hospital. The screening population consisted of individuals aged older than 50, with or without gastroesophageal reflux disease (GERD) symptoms. The conclusion of the first study [1] was that both hospital and mobile van uTNE screening had comparable clinical effectiveness to sEGD (complete examination of the esophagus in 96% to 100% of cases, and similar participation rates [40% to 45%] and safety profile). Mean recovery time with uTNE was significantly shorter compared to sEGD (15 minutes versus 1 hour). Rates of successful biopsy acquisition were significantly lower in the uTNE groups compared to sEGD due to inability to advance the TNE scope with the biopsy sheath through narrow nasal passages and patient intolerance (80% versus 100%), but switching to a smaller sheath allowed subsequent esophageal examination [1, 3]. Esophagitis was diagnosed in 32% and Barrett esophagus in 8% of screened individuals [1]. The current study [2] published in Endoscopy International Open expands upon the previous findings and concludes that the overall quality and gastroesophageal junction visualization of uTNE and sEGD are comparable. To better understand the big picture in which this paper appears, we need to ask ourselves a few questions.

Is capnography mandatory during sedation for endoscopy

Sedation during endoscopic procedures needs to ensure adequate tissue oxygenation, which depends on good cardiovascular and respiratory function. These parameters need to be monitored non-invasively as it is difficult to predict how a certain patient will respond to sedation. Tissue oxygenation is monitored using oximetry. Cardiovascular function is monitored by measuring blood pressure and pulse. Finally, respiratory function is monitored by assessing airway patency and respiratory rate in cases of spontaneous ventilation and with capnography when a patient is intubated and mechanically ventilated. A capnograph monitor measures the partial pressure of end tidal CO2 (P ETCO2) in the expired air at any given moment and expresses it as a graph usually depending on time (capnography). The absolute values of P ETCO2 and the curve shape offer information on metabolic, respiratory, and cardiovascular function 1: P ETCO2 increases as a result of metabolic causes (malignant hyperthermia, severe sepsis), cardiovascular causes (CO2 insufflation, treatment of acidosis), and respiratory causes (hypoventilation, chronic obstructive pulmonary disease (COPD), asthma). P ETCO2 decreases as a result of metabolic causes (hypothermia, metabolic acidosis), cardiovascular causes (profound hypovolemia), and respiratory causes (hyperventilation, pulmonary edema). In intubated and ventilated patients P ETCO2 values and curve shape also offer information when technical malfunction occurs. For a sedated patient in spontaneous ventilation, hypoventilation (by airway obstruction or central respiratory depression) will likely precede hypoxemia. Hence, if the patient is monitored using a capnograph machine, when hypoventilation occurs, P ETCO2 increases and the shape of the capnography curve is modified. This may trigger an adequate response from the person monitoring the anesthesia (chin thrust, sedative dose modification, oxygen supplementation) so as to prevent hypoxemia. As hypoxemia is an adverse reaction to sedation in endoscopy, are we doing enough for respiratory (as well as metabolic and cardiovascular) monitoring for patients under spontaneous respiration? Do we need capnography for these patients? If the answer is yes, then the subsequent questions will be: Should we use it for moderate (midazolam) sedation, deep (propofol) sedation or both? Should we use it for anesthesiologist, for non-anesthesiologist (nurse) administered sedation or both? Should we use it for some “high risk” procedures or for all? Should we use it for some “high risk” patients or for all? What should the precise trigger be for intervention in capnography monitoring? What should the exact intervention be to prevent hypoxemia? And finally, (when) is it cost efficacious? The American Society of Gastrointestinal Endoscopy (ASGE) does not endorse the use of capnography for moderate sedation, or for moderate risk procedures (routine endoscopy and colonoscopies), but only for endoscopic retrograde cholangiopancreatography (ERCP) or endoscopic ultrasound procedures 1 2 3. Even so, the utility of capnography monitoring for ERCP procedures has recently been questioned by Klare et al. 4. In their comparative prospective study on 242 patients with propofol-based sedation, hypoxemia incidence was not significantly reduced in the additional capnography arm compared with standard monitoring in intent to treat analysis (38.0 % vs. 44.4 %, P = 0.314). Additional capnographic monitoring only resulted in improved detection of apnea compared to standard monitoring (64.5 % vs. 6.0 %, P < 0.001). However, one patient receiving standard monitoring experienced apnea episodes before the development of hypoxemia and cardiac arrest, which subsequently led to his death. It is worth mentioning that, in a retrospective analysis of more than 70 000 procedures, Goudra et al. 5 have shown that most cardiac arrests (72 %) were airway management related and occurred mostly during propofol-based sedation (90 %). So capnography may also be beneficial for prevention of cardiovascular related events. Conway et al. 6 have recently reviewed the homogenous pooled data on three comparative randomized controlled trials on 1823 adults undergoing (mostly) colonoscopies, with (mostly) nurse administered propofol sedation by Beitz et al. 7, Slagelse et al. 8, and Friedrich-Rust et al. 9. It has been proven that capnography monitoring with hypoventilation triggering prompt supplemental oxygen significantly reduces hypoxemia from 207/1000 to 120/1000 cases, relative risk (95 %CI) 0.59 (0.48 – 0.73), P < 0.001. Can this effect, valid for nurse administered propofol, be extended to anesthesiologist monitored sedation? However, non-anesthesiologist administered propofol sedation is still not endorsed academically in Europe 10 11. In this issue of EIO, Saunders et al. 12 have designed a comprehensive model taking into account the American Society of Anesthesiology (ASA) risk group, age, and body mass index (BMI) distribution in a hypothetical cohort of 8000 patients. The model was used to simulate adverse events and costs during endoscopy procedures under deep and moderate sedation, with and without the use of capnography. The authors proved that capnography is cost effective even for moderate sedation, with 27.2 % and 18.0 % reductions in the proportion of patients experiencing an adverse event during deep and moderate sedation, respectively. The median number needed to treat to avoid any adverse event was 8 for deep sedation and 6 for moderate sedation. This resulted in cost savings per procedure of USD 85 (deep) or USD 35 (moderate) that accounted for the additional upfront purchase cost, but the cost savings were only realized if more than 300 procedures were performed. Aspects of their findings were communicated in abstract form at the International Society for Pharmacoeconomics and Outcomes Research 2015 meeting, in a study funded by Covidien/Medtronic, the manufacturers of capnograph machines 13. The question still remains open, at least for midazolam-based sedation, as very recently, Barnett et al. 14 did not find any advantages of capnography monitoring in their comparative study on 966 patients undergoing colonoscopy: similar adverse events (8.2 % no capnography vs. 11.2 % with capnography, P = 0.115) with an increased cost of 11.8 USD per case. In conclusion, there are still many questions waiting to be answered. There are apparently discordant trial results, as one should take into account many confounding variables – patient, procedure, sedation, and physician related. Capnography, as a measure of both cardiovascular and respiratory function, does not appear to increase the procedure risk. The jury is still out on whether it decreases the risks and if this decrease is cost-effective.

Sa1400 Endoscopic Sub-Mucosal Dissection With a New Water Jet System Using a Bi-Fonctional Catheter: First Prospective Trial

lesions. Learning ESD is particularly challenging for US endoscopists due to lack of an adequate training platform. Aim: To report our experience in learning ESD in a live intubated, non-survival porcine model. Methods. Study was approved by our animal lab facility. Two endoscopists with minimal or no ESD experience performed the procedures. After adequate sedation, EGD (GIF 160, Olympus) was performed with a transparent cap attached. ESD was performed in gastric antrum, body, cardia and esophagus. Hybrid knife IT however can be used as marker for the control of technique. Perforations occurred in 3/20 (15%) resections in the former period and none (0/24) in the later period. These were successfully closed with clips allowing us to continue the procedure. Conclusion: We report our initial ESD experience and learning curve. As study progressed, procedure duration decreased along with the rate of MP injury & specimen size increased. In the later half we reached 100% en bloc resection rate & 0% perforation rate. Circumferential incision was the major obstacle in learning ESD, at least in our hands and it improved in the 2nd half. This model was a learning foundation for us that later enabled us to successfully perform ESD in selected patients with excellent results.

Non-Barrett's esophageal and gastric tumors: diagnosis and treatment.

The 2012 Digestive Disease Week (DDW; 19 – 22 May, San Diego, California, USA) presented small-step advances in the field of non-Barrett’s esophageal and gastric tumors. In patients with ear – nose – throat (ENT) cancer, narrow-band imaging (NBI) might be useful in endoscopic screening for early esophageal squamous neoplasia, but confirmation of its role has yet to be reported. The yield and intervals of endoscopic screening for gastric neoplasia are better understood, and so are the results and complications of gastroesophageal endoscopic submucosal dissection (ESD) together with their predictive factors. Endoscopic therapy of advanced tumors was another important theme at DDW, with ESD after radiotherapy for advanced esophageal cancer and gastrojejunostomy for neoplastic gastric outlet obstruction being reported. Relevant abstracts are discussed below.