Rat models of high risk colorectal anastomoses

Abstract Purpose: To evaluate the most frequent surgical techniques of high-risk colorectal anastomoses in rats. Methods: Wistar rats were enrolled in three different models comprising inflammatory (TNBS enema), vascular (portal vein occlusion) or obstructive (a non-ischemic constricting ring) mechanisms associated with colonic anastomosis that had accomplished after these former lesions. Histological analyses (Hematoxylin and eosin and Picrosirius red) were performed. Results: All anastomoses techniques were associated with risk factors and had complications, mainly anastomotic leakage. In Study 1, the use of a pharmacological agent, trinitrobenzene sulfonic acid (TNBS) mimicked an inflammatory bowel disease such as Crohn's disease with 50% of anastomosis leakage, the higher percentage among all models tested. In Study 2, after portal ischemia followed by reperfusion it was observed a dense neutrophil infiltrate in the midst of necrotic tissue and fibrin at the anastomotic site and 5 days after the anastomosis, no collagen was produced. In Study 3, 5 days after the mechanical obstruction some denuded areas of epithelium with marked oedema of mucosa and submucosa were seen, at the anastomotic site and anastomosis group showed some reduction of collagen density when compared with Control/Sham group. Conclusion: All the experimental surgical techniques tested in rats were associated with high-risk colorectal anastomoses and were useful to study colonic anastomotic healing and intestinal leakage.

Utilidad del estudio contrastado precoz del tracto digestivo superior después de cirugía bariátrica: ¿se justifica su uso rutinario? / Usefulness of upper gastrointestinal series to detect leaks in the early postoperative period of bariatric surgery

Background: Postoperative leaks are the most undesirable complication of bariatric surgery and upper gastrointestinal (GI) series are routinely ordered to rule them out. Despite the published literature recommending against its routine use, it is still being customarily used in Chile. Aim: To examine the usefulness of routine upper GI series using water-soluble iodinated contrast media for the detection of early postoperative leaks in patients undergoing bariatric surgery. Material and Methods: A cohort of 328 patients subjected to bariatric surgery was followed from October 2012 to October 2013. Most of them underwent sleeve gastrectomy. Results: Upper GI series on the first postoperative day were ordered to 308 (94%) patients. Postoperative leaks were observed in two patients, with an incidence of 0.6%. The sensitivity for upper GI series detection of leak was 0% and the negative predictive value was 99%. Conclusions: Routine upper GI series after bariatric surgery is not useful for the diagnosis of postoperative leak, given the low incidence of this complication and the low sensitivity of the technique.

Fluoroscopically Guided Three-Tube Insertion for the Treatment of Postoperative Gastroesophageal Anastomotic Leakage

OBJECTIVE: To retrospectively evaluate the feasibility and effectiveness of three-tube insertion for the treatment of postoperative gastroesophageal anastomotic leakage (GEAL). MATERIALS AND METHODS: From January 2007 to January 2011, 28 cases of postoperative GEAL after an esophagectomy with intrathoracic esophagogastric anastomotic procedures for esophageal and cardiac carcinoma were treated by the insertion of three tubes under fluoroscopic guidance. The three tubes consisted of a drainage tube through the leak, a nasogastric decompression tube, and a nasojejunum feeding tube. The study population consisted of 28 patients (18 males, 10 females) ranging in their ages from 36 to 72 years (mean: 59 years). We evaluated the feasibility of three-tube insertion to facilitate leakage site closure, and the patients' nutritional benefit by checking their serum albumin levels between pre- and post-enteral feeding via the feeding tube. RESULTS: The three tubes were successfully placed under fluoroscopic guidance in all twenty-eight patients (100%). The procedure times for the three tube insertion ranged from 30 to 70 minutes (mean time: 45 minutes). In 27 of 28 patients (96%), leakage site closure after three-tube insertion was achieved, while it was not attained in one patient who received stent implantation as a substitute. All patients showed good tolerance of the three-tube insertion in the nasal cavity. The mean time needed for leakage treatment was 21 +/- 3.5 days. The serum albumin level change was significant, increasing from pre-enteral feeding (2.5 +/- 0.40 g/dL) to post-enteral feeding (3.7 +/- 0.51 g/dL) via the feeding tube (p < 0.001). The duration of follow-up ranged from 7 to 60 months (mean: 28 months). CONCLUSION: Based on the results of this study, the insertion of three tubes under fluoroscopic guidance is safe, and also provides effective relief from postesophagectomy GEAL. Moreover, our findings suggest that three-tube insertion may be used as the primary procedure to treat postoperative GEAL.