Small Animal Surgical Emergencies. Группа авторов
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As previously mentioned for gastrotomy, contaminated instruments should be replaced with sterile instruments for enterotomy closure. Gloves should also be changed. Following removal of a discrete foreign body, closure is performed using a simple interrupted or simple continuous appositional pattern using monofilament synthetic absorbable material (polydioxanone, polyglyconate, glycomer 631). Incorporation of the submucosal layer is critical for enteric closure, as this is the holding layer of the intestines. In cases of perforation or questionable intestinal viability, a resection and anastomosis may be necessary. Resection and anastomosis requires careful attention when assessing the blood supply to the area to be resected. Only those blood vessels directly supplying the area of resection should be ligated. The vessels should be triple ligated, allowing two ligations to stay in the body and one to stay on the resected intestine to prevent bleeding during resection. Carmalt forceps can be placed on the section of intestine that is being resected to prevent spillage of ingesta, and Doyen forceps or the fingers of an assistant surgeon can be used to atraumatically prevent ingesta spillage from the ends to be anastomosed. The anastomosis can be achieved with suturing in a simple interrupted pattern, simple continuous pattern, or a combination of both patterns using monofilament synthetic absorbable material (polydioxanone, polyglyconate, glycomer 631).
Figure 5.7 (a) and (b) Discrete foreign body lodged within the small intestine of a dog. The incision is made aboral (arrow) to the foreign body. Length of the incision (line B) is equal to the width of the foreign body in the intestine (line A).
As the mesenteric border is typically covered in fat, it is crucial that the first suture is placed at the mesenteric border in order to allow for appropriate visualization of the intestinal wall in that area. Another option for performing an anastomosis is to create a functional end‐to‐end anastomosis using GIA™ and TA™ staplers. Studies comparing dehiscence rates between sutured and stapled anastomoses have shown either no significant difference in dehiscence rates between the two options [60] or decreased risk of dehiscence with the stapled anastomoses [61].
In the ileum, identifying the appropriate location of the enterotomy incision for foreign body removal can be challenging. The standard duodenal or jejunal enterotomy incision is made on the antimesenteric border of the intestine. However, the antimesenteric vessel of the ileum precludes use of this site, and enterotomy incisions must be made between the mesenteric and antimesenteric borders. In cases of perforation or questionable intestinal viability in the region of the ileum, the decision to perform a resection and anastomosis frequently necessitates anastomosis of the distal jejunum or proximal ileum to the proximal colon. Disparity between the luminal diameters of these two segments precludes routine end‐to‐end anastomosis of small intestinal and colonic segments. Incising the small intestine at a greater angle and then correcting the remaining luminal disparity by incising the small intestine longitudinally at the antimesenteric border can address the discrepancy in lumen diameter (Figures 5.8 and 5.9). The combination of these techniques enlarges the opening of the small intestine to equal the size of the colon. Alternatively, the colon can be partially sutured to equal the lumen size of the small intestine.
After enterotomy or resection and anastomosis is completed, a leak test can be performed to evaluate the closure. This can be achieved by compressing the intestine with either Doyen forceps or an assistant surgeon's fingers 5 cm from each end of the enterotomy or anastomosis and using a small gauge needle to inject sterile saline into the intestine until the segment between the Doyens or fingers is taut. The suture line should be evaluated for any fluid leakage. Additional sutures should be placed at any site with fluid leakage. Afterwards, the peritoneal cavity should be lavaged thoroughly with warm sterile saline with the saline removed via suction. Following lavage, an omental wrap or serosal patch may be placed based on surgeon preference.
Linear Foreign Body
When considering linear foreign body removal, the appropriate site of the enterotomy incision is determined by evidence of bowel plication in response to gentle tension placed on the proximal aspect of the foreign body. When gastrotomy is performed and the proximal aspect of the linear foreign body identified, gentle traction is applied to the body as it exits the stomach. If the linear foreign body is not easily retracted into the stomach, the site of tethering within the small intestine, indicated by plication of the bowel, is the appropriate site for enterotomy (Figure 5.10). In some cases, this procedure must be repeated and additional enterotomies performed to remove the entire linear foreign body. Each enterotomy site is closed using an appositional, side‐to‐side or end‐to‐end, closure of the incision with either a simple interrupted or simple continuous pattern. Anderson et al. reported the use of a single enterotomy technique for the removal of linear foreign bodies [12]. With this technique, the foreign body is anchored to a red rubber catheter, introduced into the bowel lumen and milked in an aboral direction through the length of the GI tract and exited through the anus [12]. This technique is valuable in cases with linear foreign bodies made of material that is amenable to anchoring to the red rubber catheter, such as sewing thread or dental floss. Linear foreign bodies such as towels and clothing are not generally suitable candidates for this procedure in the authors' experience.
Figure 5.8 Luminal disparity can be corrected by transecting the smaller intestinal segment at an angle before performing the anastomosis.
Source: Brown [62]. Reproduced with permission from Elsevier.
During removal, careful inspection of the mesenteric border is crucial as compromise of the integrity of the bowel wall may occur secondary to the motion of the linear foreign body. Evidence of hemorrhage within the fat at the mesenteric border or areas of omental adhesion to the small bowel may indicate the presence of perforation and should be investigated (Figure 5.11). In the event of perforation of the intestine at the mesenteric border, resection and anastomosis are indicated, as debridement and successful closure is difficult to achieve in this area due to lack of adequate visualization and possible compromise of vascular integrity.
Following