Enteral stents

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DR VARUN K ENTERAL STENTS

description

stents used in gastroenterology

Transcript of Enteral stents

  • 1. DR VARUN K

2. History Introduction Types of Stents Indications for stenting Procedure Side effects Esophageal stents Gastroduodenal stents Colonic stents 3. Invented in 1856 by the English dentist Charles Stent . Jan F. Esser, a Dutch plastic surgeon who in 1916 used the word stent to describe a dental impression compound to craft a form for facial reconstruction The first (self expanding) "stents" used in medical practice in 1986 by Ulrich Sigwart in Lausanne were initially called "Wallstents". Julio Palmaz et al. created a balloon expandable stent that is currently used 4. The evolution of enteral stents has gone through stages over the last 125 years. Sir Charters Symonds was the first to successfully place an esophageal prosthesis across a malignant stricture. There were many modifications of rigid esophageal stents in which various materials (wood, metal, plastic, latex) and designs were used 5. Celestin designed a new prosthesis and, following its commercial availability in the 1970, the stent revolution accelerated. The rigid prosthesis (plastic and latex) was extensively used from the 1970s to the 1990s, but the complication rates and mortality associated with insertion-related perforations remained significant. In the early 1990s, self-expandable metal stents (SEMS) were developed for esophageal use a decade after their introduction into the vascular and biliary tree 6. Stents are devices used to maintain or restore the lumen of hollow organs, vessels, and ducts. There are three types of expandable stents: metal, plastic, and biodegradable 7. There are three varieties of metal stents: uncovered, partially covered, and fully covered. The advantage of covered stents is that they resist tumor ingrowth, but they have a higher migration rate, especially when fully covered but advantage of potentially being removable. 8. Partially covered stents are uncovered at their ends, which allows the stent to embed in the tissue and helps to prevent migration. Uncovered stents are less likely to migrate, but are subject to tumor ingrowth and resultant obstruction. 9. SEMSs consist of woven, knitted, or laser-cut metal mesh cylinders that exert self-expansive forces until they reach their maximum fixed diameter. SEMSs are composed of stainless steel, alloys such as elgiloy and nitinol, or a combination of nitinol and silicone. 10. Elgiloy, an alloy composed primarily of cobalt, nickel, and chromium, is corrosion resistant and capable of generating high radial forces. Nitinol, an alloy of nickel and titanium, yields increased flexibility that is helpful for stenting sharply angulated regions at the cost of lesser radial force. 11. To prevent tumor ingrowth, the interstices between the metal mesh of esophageal SEMSs may be wholly or partially covered by a plastic membrane or silicone. For tumors located near the GE junction (Esophageal Z-stent with Dua Anti-reflux valve; Wilson-Cook Medical, Winston-Salem, NC) uses an extended polyurethane membrane 8 cm beyond the metal portion of the stent to prevent gastroesophageal reflux 12. An SEPS (Polyflex; Boston Scientific, Natick, Mass) has been developed for esophageal strictures. This stent has a woven polyester skeleton and is completely covered with a silicone membrane. 13. The silicone prevents tissue in growth through the mesh. Polyester braids on the external surface anchor the stent to the mucosa to limit migration. 14. Esophageal Degradable BD (Ella-CS, Czech Republic) is made from woven surgical suture material, polydioxanone. It is uncovered and does not have an anti-reflux valve. The stent fully degrades in approximately three months 15. PROXIMAL RELEASE DISTAL RELEASE COAXIAL RELEASE SUTURE RELEASE 16. Dysphagia from esophageal malignancy. benign esophageal strictures (peptic, radiation induced, anastomotic, and caustic). Postoperative leaks. iatrogenic perforations. 17. external compression from extraesophageal tumors. tracheoesophageal fistulas. Achlasia cardia. Bleeding varices. 18. Stents vary in length from 6 to 19.5 cm and in shaft diameter from 10 to 23 mm. Wallflex (Boston Scientific, Inc, Natick, MA) partially and fully covered nitinol stents without an anti-reflux valve Esophageal Z stent (Cook Endoscopy, Winston-Salem, NC) partially covered stainless steel stent, available only with the Dua anti-reflux variant 19. Evolution (Cook Endoscopy) partially covered and fully covered nitinol stents without an anti-reflux valve Ultraflex stent (Boston Scientific, Inc) partially covered and uncovered nitinol stents without an anti-reflux valve Alimaxx-E stent (Merit Endotex) fully covered nitinol stent with and without an anti-reflux valve. Niti-S (Taewoong Medical Co, Korea) fully covered nitinol stent without an anti-reflux valve; this stent comes in two versions, the covered Niti-S and the double-layered Niti-S that has an additional layer of nitino 20. ELLA-CS FerX-Ella Esophageal Stent -Stainless steel (fully covered with polyethylene) SX-Ella Esophageal Stent- Nitinol (fully covered with silicone) 21. 0Able to consume a normal diet 1Dysphagia with certain solid foods 2Able to swallow semi-solid soft foods 3Able to swallow liquids only 4Unable to swallow saliva (complete dysphagia) 22. Assessment of the length of the stricture and degree of obstruction is the first step If the stricture is too tight to advance a standard gastroscope, an ultrathin endoscope may be used. To guide accurate stent deployment, the proximal and distal ends of the stricture need to be marked appropriately 23. During stent selection, it is important to choose a stent length that is 4 cm longer than the stricture being stented. This allows for 2 cm of stent on either end of the stricture to decrease the risk of migration. 24. Foreshortening is the property of the stent by which, on fluoroscopy, the stent constrained in its catheter will appear longer than the unconstrained deployed stent length. stenting a stricture in the cervical esophagus ensure at least a 2-cm distance between the proximal end of the stent and the upper esophageal sphincter 25. misplacement (0.3 percent), failed expansion (3.9 percent), failed deployment (0.8 percent), and migration (0.3 percent) gastroesophageal reflux disease (3.7 percent), recurrent dysphagia (8.2 percent), tracheoesophageal fistula (2.8 percent), 26. bleeding (3.9 percent), perforation (0.8 percent), and death within 30 days that was not related to immediate stent placement (7.4 percent) Esophageal self-expandable metallic stents--indications, practice, techniques, and complications: results of a national survey.Ramirez FC, Dennert B, Zierer ST, Sanowski RA Gastrointest Endosc. 1997;45(5):360 27. Benign esophageal strictures are classified as simple or complex. Simple strictures are straight and short (< 1 cm) and can be easily passed with a normal diameter (8 to 10 mm) endoscope. Complex strictures are often longer (> 2 cm), angulated, and sufficiently narrow that passing a normal diameter endoscope is difficult. 28. Complex strictures are due to radiation, photodynamic therapy, caustic ingestions, and surgical anastomoses. Refractory strictures are defined as those that cannot be dilated to 14 mm over 5 sessions at 2-week intervals. Recurrent strictures are defined as those that do not maintain satisfactory luminal diameter for 4 weeks after dilation to at least 14 mm. Kochman M, McClave S, Boyce H. The refractory and recurrent esophageal stricture a definition. . 2005;62(3):474-475 29. SEPS should optimally be left in place for at least six weeks to allow for remodeling of the scar tissue. A longer period may be required in patients with post- radiation or anastomotic strictures, which have a greater tendency to recur. 30. Systematic review: the role of self-expanding plastic stents for benign oesophageal strictures.Repici A, Hassan C, Sharma P, Conio M, Siersema P Aliment Pharmacol Ther. 2010;31(12):1268. Results:Data of 10 studies with 130 treated patients were included. SEPS insertion was technically successful in 128 of 130 patients (98%).. 31. A comparison of temporary self-expanding plastic and biodegradable stents for refractory benign esophageal strictures. van Boeckel PG, Vleggaar FP, Siersema P Clin Gastroenterol Hepatol. 2011;9(8):653 Placement of SEPSs or biodegradable stents provides long-term relief of dysphagia in 30% and 33%, respectively, of patients with RBES. Biodegradable stents require fewer procedures than SEPSs, offering an advantage. Although stent placement is a viable strategy in patients with RBES, the ideal strategy still needs to be defined 32. The use of expandable uncovered metal stents for benign esophageal strictures is not recommended. 33. Four studies examined the use of a FCSEMS without flared flanges (Alimaxx-ES esophageal stent, Merit Medical Systems Inc) in benign esophageal disease . Treatment success varied from 21 to 100 percent, depending upon the indication for stent placement (fistula/leak or perforation and strictures 34. Three additional types of newly developed FCSEMSs with the presence of flared flanges (ie, "dog bone" design) have been used with success: Wallflex esophageal stent (Boston Scientific Inc, Natick, MA) Bonastent esophageal stent (EndoChoice Inc, Alpharetta, GA) Evolution esophageal stent (Cook Medical Inc, Winston-Salem, NC) 35. A comparison of the temporary placement of 3 different self- expanding stents for the treatment of refractorybenign esophageal strictures: a prospective multicentre study. Temporary placement of a biodegradable stent or of a FCSEMS in patients with RBES may lead to long-term relief of dysphagia in 30 and 40% of patients, respectively. The use of SEPSs seems least preferable, as they are associated with frequent stent migration, more reinterventions and few cases of long-term improvement. 36. In a retrospective study of 153 patients, Eickhoff and colleagues found comparable rates of survival, recurrent dysphagia, and improvement in dysphagia scores between SEMS and SEPS; however, SEMS had a much lower complication rate than SEPS (9% vs 22%, respectively) Although SEPS have been shown to be effective, recent studies have shown that they may not be preferred over SEMS. Eickhoff A, Knoll M, Jakobs R, et al. Self-expanding metal stents versus plastic prostheses in the palliation of malignant dysphagia: long-term outcome of 153 consecutive patients. J Clin Gastroenterol. 2005;39:877885 37. Self-expanding plastic stent to palliate symptomatic tissue in/overgrowth after self-expanding metal stent placement for esophageal cancer. Conio M, Blanchi S. Filiberti R, De Ceglie A. This case series supports the use of a SEPS to palliate dysphagia from tissue in/overgrowth of a SEMS. Future clinical trials with larger patient samples are warranted. 38. Temporary self-expanding metallic stents for achalasia: A prospective study with a long-term follow-up Ying-Sheng Cheng, Fang Ma, Yong-Dong Li, Ni-Wei Chen, Wei-Xiong Chen, Jun-Gong Zhao, and Chun-Gen Wu A temporary SEMS with a diameter of 30 mm is associated with a superior long-term clinical efficacy in the treatment of achalasia compared with a SEMS with a diameter of 20 mm or 25 mm. 39. International Journal of Hepatolog Volume 2012 Role of Self- Expandable Metal Stents in Acute Variceal Bleeding .Fuad Maufa and Firas H. Al-Kawas SEMS placement using especially designed stent (SX-Ella Danis stent, currently not available in USA) is a new promising alternative therapeutic technique that can be used in patients with refractory esophageal variceal bleeding. Patients who failed initial standard therapy, have contraindications, or are unsuitable for those therapies are good candidates at this time 40. Esophageal malignancy: SEMS. Tumor ingrowth and dysphagia after SEMS: SEPS RBES: SEMS and Biodegradable stents. Tracheo-esophageal fistula: SEMS and if required tracheal SEMS. Post op leaks: SEPS. 41. Truong -1992 First duodenal stent. Palliation of malignant gastric outlet obstruction in the antrum, proximal small bowel, and gastroenteric anastomoses . Benign gastric outlet obstruction. SEMS placement have demonstrated 95% technical success and 85% to 95% clinical success with adequate decompression of outlet obstruction and patients ability to tolerate at least a mechanical soft diet. 42. Wallflex Duodenal(Duloflex study) Wallstent Enteral (Boston Scientific), Evolution Duodenal (Cook Medical, Bloomington,IN) All uncovered SEMSs deployed through the endoscope, have been approved for palliation of malignant gastric outlet obstruction. 43. A radiographic contrast study should first be obtained to assess the length of the stricture and degree of obstruction and to rule out additional sites of obstruction Peritoneal carcinomatosis is a relative contraindication to stent placement, although limited recent data suggest that these patients have similar outcomes to those without carcinomatosis 44. If biliary obstruction is present or impending, it is prudent to place a biliary stent before gastroduodenal stenting to avoid difficult biliary access at a later date. Stricture dilation before stent placement is usually unnecessary and carries a risk of perforation 45. A throughthe- scope stent of appropriate size, generally 4 cm longer than the size of the stricture, is then advanced over the guidewire and deployed under endoscopic an fluoroscopic guidance. At least a 2 cm length of stent should be flared at both ends of the stricture to attain an appropriate waist; otherwise, overlapping stents may be needed to fully traverse the length of the stricture 46. Mild adverse events include abdominal discomfort, mild fever, and occasional vomiting without obstruction. Major adverse events occurring within the first week include bleeding, perforation, stent migration, severe pain, fever, and jaundice Significant late adverse events include fistula formation, stent obstruction, late perforation or bleeding, biliary obstruction, and stent migration 47. Surgical gastrojejunostomy or endoscopic stent placement for the palliation of malignant gastric outlet obstruction (SUSTENT study): a multicenter randomized trial.Jeurnink SM, Steyerberg EW, vanHooft JE, van Eijck CH, Schwartz MP, Vleggaar FP, Kuipers EJ, Siersema PD Dutch SUSTENT Study Group CONCLUSIONS: Despite slow initial symptom improvement, GJJ was associated with better long-term results and is therefore the treatment of choice in patients with a life expectancy of 2 months or longer. Because stent placement was associated with better short-term outcomes, this treatment is preferable for patients expected to live less than 2 months. 48. Safety and efficacy of a new non-foreshortening nitinol stent in malignant gastric outlet obstruction (DUONITI study): a prospective, multicenter studyvan Hooft JE, van Montfoort ML, Jeurnink SM, Bruno MJ, Dijkgraaf MG, Siersema PD, Fockens P.Endoscopy. 2011 Aug;43(8):671-5 Placement of a new non-foreshortening nitinol enteral stent is safe and without major complications. This stent design produces significant relief of obstructive symptoms and improves quality of life in patients with incurable malignant GOO 49. Endoscopic stent management of leaks and anastomotic strictures after foregut surgery. Yimcharoen P, Heneghan HM, Tariq N, Brethauer SA, Kroh M, Chand B.Surg Obes Relat Dis. 2011 Sep-Oct;7(5):628-36 Endoscopic stent management of anastomotic complications after foregut surgery is effective in resolving symptoms, expediting enteral nutrition, and particularly successful for treating anastomotic leaks. 50. Application of stent placement or nasojejunal feeding tube placement in patients with malignant gastric outlet obstruction: a retrospective series of 38 cases. Lin CL, Perng CL, Chao Y, Li CP, Hou MC, Tseng HS, Lin HC, Lee KC.J Chin Med Assoc. 2012 Dec;75(12):624-9 NJ tube placement and duodenal stent placement are both effective and safe treatments for patients with MGOO. Both groups had similar complication rates and survival rates. While NJ tube placement is associated with lower costs, stent placement has a longer duration of patency, superior oral intake, and a lower reintervention rate. We suggest that stent placement should be considered first in patients who are able to afford the related costs 51. Antral localization worsens the efficacy of enteral stents in malignant digestive tumorsDolz C, Vilella , Gonzlez Carro P, Gonzlez Huix F, Espins JC, Santolaria S, Prez Roldn F, Figa M, Loras C, Andreu H.Gastroenterol Hepatol. 2011 Feb;34(2):63-8 The palliative treatment of malignant gastric outlet obstruction with a uncovered metal stent produces a significant improvement of oral food intake and maintains the overall quality of life index. The antral localization is associated with a lower efficacy of the procedure 52. Colorectal stenting has become an important tool in the palliation of advanced disease Management of acute colon obstruction as a possible bridge to Surgery Benign colon strictures Clinical success rates, defined as relief of obstructive symptoms, are reported in 85% to 90% of patients. 53. Colon SEMSs may be covered or uncovered, throughthe- scope or not through-the-scope Only uncovered stents are currently approved in the United States Smaller-diameter stents are generally used in the right side of the colon and larger-diameter stents in the left side of the colon to prevent solid stool impaction. 54. Ideally, a radiologic imaging study such as a barium enema or CT scan with rectal contrast should be obtained before stent placement to assess the degree of obstruction and the length and location of the stricture Prophylactic antibiotics should be considered in patients with complete obstruction because air insufflation may lead to microperforation 55. When the colonoscope is advanced, air insufflation should be minimized to avoid the risk of proximal bowel distension and perforation. Ideally, a 2-cm segment of stent should be spared beyond both the proximal and distal edges of the stricture to allow the formation of a waist in the middle and a flare at both ends. 56. Rectal stents should be deployed at least 2 cm proximal to the anal verge to avoid pain and incontinence Stents that are not through-the-scope are deployed under fluoroscopic guidance by using a stiff guidewire, and endoscopic views may be obtained by advancing a regular gastroscope alongside the stent delivery system 57. Successful stent deployment is generally associated with immediate passage of stool and flatus. Failure to achieve decompression could be a result of incomplete stenting of the entire length of the stricture, additional sites of intestinal obstruction, early stent migration, incomplete expansion of the stent, or fecal impaction. 58. Perforation, bleeding, Stent migration, abdominal pain, recurrent obstruction due to stent malposition, and tissue or tumor ingrowth overgrowth. Rectal SEMS placement may cause tenesmus and incontinence. 59. Comparison of uncovered stent with covered stent for treatment of malignant colorectal obstruction. Lee KM, Shin SJ, Hwang JC, Cheong JY, Yoo BM, Lee KJ, Hahm KB, Kim JH, Cho SW Gastrointest Endosc. 2007 Nov;66(5):931-6 Insertion of either an uncovered or covered stent is similarly an effective treatment modality of malignant colorectal obstruction for preoperative purposes. However, there are no advantages of covered stents over uncovered stents during the follow-up period in the palliative purpose 60. colonic stenting for malignant obstruction is associated with less morbidity and cost but no difference in overall survival. Targownik LE, Spiegel BM, Sack J, et al. Colonic stent vs emergency surgery for management of acute left-sided malignant colonic obstruction: a decision analysis. Gastrointest Endosc 2004;60:865-74. Cheung HYS, Chung CC, Tsang WWC, et al. Endolaparoscopic approach vs conventional open surgery in the treatment of obstructing left-sided colon cancer. Arch Surg 2009;144:1127-32. 61. Colorectal Dis. 2014 Apr;16(4):239-45. doi: 10.1111/codi.12389. Systematic review of self-expanding stents in the management of benign colorectal obstruction. Currie A, Christmas C, Aldean H, Mobasheri M, Bloom IT Complication rates in stenting for benign colorectal obstruction are higher than for malignant obstruction. On the basis of limited published evidence, stenting cannot be recommended for benign colorectal obstruction 62. A retrospective analysis of early and late outcome of biodegradable stent placement in the management of refractory anastomotic colorectal strictures. Repici A, Pagano N, Rando G, Carlino A, Vitetta E, Ferrara E, Strangio G, Zullo A, Hassan C Surg Endosc. 2013 Jul;27(7):2487-91 This retrospective analysis of a limited number of patients demonstrated that nondedicated esophageal BD stents are associated with high risk of migration and clinical success in less than 50 % of patients. Dedicated stents with large diameter and antimigration findings could potentially improve the outcome of patients with refractory benign colorectal strictures 63. Malignant colorectal obstruction: SEMS Covered and Uncovered stents equal efficacy. Benign strictures: No role of stents 64. ASGE GUIDELINES UPTODATE REVIEW ARTICLES 65. THANK YOU