Therapeutic endoscopy for dysphagia and delayed gastric emptying

Abstract

This PhD thesis focuses on the endoscopic treatment of benign and malignant dysphagia and delayed gastric emptying. Dysphagia due to a benign anastomotic stricture occurs in 40% of patients after esophagectomy and often requires ongoing endoscopic dilations. We evaluated whether corticosteroid injections added to dilation improves clinical outcome. We found a non- significant improvement in total number of dilations needed or dysphagia free period, and a higher risk of candida esophagtis in the patients treated with corticosteroids and cannot recommended steroid injections for this indication. Esophageal stent placement is considered to provide a longer dysphagia free period, but in benign strictures stent removal can be challenging due to esophageal imbedment as a result of hyperplastic tissue. By placing a second stent in the originally placed stent, pressure necrosis of hyperplastic tissue occurs, which ensures safe stent removal. We demonstrated that this stent-in-stent technique is a safe way to remove embedded esophageal stents. Another option is to place biodegradable stent, made of polydioxanone, which gradually degrades over 3 months time. We demonstrated that, although a considerable number of side effects occurred, this stent was effective in the treatment of dysphagia. For malignant dysphagia due to esophageal cancer, stent placement provides immediate dysphagia relief, while endoluminal radiotherapy provides better long term results. We evaluated whether a combination of both treatments would result in both an immediate and long-term dysphagia free period. A biodegradable stent (which is dissolved after 3months) instead of a metal stent was used to avoid long term stent complications. We showed that this combination treatment did not increase dysphagia free period, but was associated with a high number of complications, such as retrostenal pain, nausea and vomiting. We also performed radial and axial force tests in vitro of various stents in an attempt to explain clinical finding after stent placement. Although we experienced that the behavior of an esophageal stent is a complex issue that cannot be explained by radial and axial force alone, we hypothesize that a high radial force and a low axial force may be the optimal combination of an effective a-traumatic esophageal stent. Delayed gastric emptying is a common complication after abdominal surgery or in critically ill patients, which often requires nasoenteral tube feeding. In clinical practice, we noticed that after transnasal endoscopic feeding tube placement feeding tubes are often still located in the stomach, due to spontaneous retrograde feeding tube migration or inadequate placement. By performing clip-assisted feeding tube placement we aimed to reduce the number of feeding tubes that were located in the stomach. In this study we showed that this technique was effective: by performing 5 clip-assisted feeding tube placements, we avoided 1 repeat endoscopy for incorrect tube placement.