Surgery of the small intestine Flashcards
Length of the small intestine
4x the length of the large intestine
1-1.5m in cats
2-5m in dogs
Blood supply of the small intestine
Cranial mesenteric artery
Duodenum of a dog
The descending duodenum receives the pancreatic and bile ducts.
The pancreatic duct and bile duct open adjacent to each other on the major duodenal papilla, which is approximately 3-6cm distal to the gastric pylorus.
They have an accessory pancreatic duct which opens on the minor duodenal papilla approximately 2cm distal to the major duodenal papilla.
The descending duodenum runs parallel to the right limb of the pancreas, which sits within the mesoduodenum.
The descending duodenum makes a hairpin bend to become the ascending duodenum.
At the hairpin bend the duodenum is tethered close to the abdominal wall by the duodenocolic ligament.
The duodenum shares its blood supply with the pancreas.
Duodenum of a cat
The first part of the duodenum, the descending duodenum receives the pancreatic and bile ducts.
The pancreatic duct and bile duct often share a common opening and only 20% of cats have an accessory pancreatic duct.
The descending duodenum runs parallel to the right limb of the pancreas, which sits within the mesoduodenum.
The descending duodenum makes a hairpin bend to become the ascending duodenum.
At the hairpin bend the duodenum is tethered close to the abdominal wall by the duodenocolic ligament.
The duodenum shares its blood supply with the pancreas.
The jejunum
The longest portion of the small intestine and hangs from its extensive mesentery, which has its root in the cranial sublumbar region.
Blood supply from the cranial mesenteric artery
The ileum
Short (approximately 15cm in dogs and shorter in cats) and is easily recognised by its antimesenteric blood vessel.
Blood supply from the cranial mesenteric artery
Cranial mesenteric artery
Supplies the small intestine.
The artery divides into branches which radiate through the mesentery of the jejunum and ileum forming anastamosing arcades.
The anastamotic links mean that a single mesenteric artery can be ligated without consequence.
The caecum
At the junction of the ileum and colon
Forms a comma shape in dogs and a snail like coil in cats
The colon
The large intestine begins with the short ascending colon and continues as the transverse colon and then the descending colon.
The rectum is that terminal part of the large intestine within the pelvis.
The colon has its own mesentery called the mesocolon.
The colon can be distinguished from the small intestine because it is often whiter in colour and has longitudinal striations due to a prominent longitudinal muscle layer.
The arterial supply has a different pattern, running parallel to the colon within the mesocolon and therefore lacking anastamotic branches.
Rate of intestinal wound healing
Rapid
Regains 75-80% of tensile strength in 2 weeks
