Dick White Referrals, SIX MILE BOTTOM, Newmarket, UK CB8 0UH BASICS OF INTESTINAL SURGERY: ANATOMY, PATHOPHYSIOLOGY, INSTRUMENTATION & SUTURING

ANATOMY The small intestine extends from the pylorus to the caecum. The most fixed portion of the small bowel is the distal duodenum, due mostly to the duodenocolic ligamentous attachment to the descending colon. This anatomical landmark must be recognized to allow proper exploration of the small intestine. The jejunum is the major portion of the small lntestine with the ileum being only 6-20 centimeters in length in most small animals. The major blood supply to the small intestine is from the cranial mesenteric artery. A portion of the proximal duodenum is supplied by the celiac artery and shares a source of blood (pancreaticoduodenal) with the right lobe of the pancreas. The wall of the small intestine comprises the mucosa, submucosa, muscularis and the serosa. The submucosal layer provides blood vessels, lymphatics and nerves. Importantly, it is also the "holding" layer which must be included in any suturing technique that is used to re-appose tissue of the small intestine.