Large Intestine Flashcards
Name 3 features that distinguish the large intestine from the small intestine.
Taeni coli - 3 layers of longitudinal muscle.
Haustrations - bulges formed by tonic contractions of taenia coli.
Epiploic appendages - small pouches of fat filled peritoneum.
What are paracolic gutters?
Potential recesses between the ascending and descending colon and posterolateral abdominal wall.
These drain away infectious material.
List all the parts of the colon and whether they’re intraperitoneal or retroperitoneal.
Appendix - mesoappendix Caecum - intraperitoneal Ascending colon - retroperitoneal Transverse colon - transverse mesocolon Descending colon - retroperitoneal Sigmoid colon - sigmoid mesocolon
Is the rectum retroperitoneal or intraperitoneal?
Retroperitoneal
What is the surface marking of the appendix?
Midway between umbilicus and anterior AS iliac spine.
What artery supply the caecum?
Ileo-colic artery.
- from SMA
What arteries supply the ascending colon?
Ileo-colic artery and right colic artery.
- from SMA
What arteries supply the transverse colon?
Middle colic artery supplies prox 2/3
- from SMA
Left colic artery supplies distal 1/3
- from IMA
What arteries supply the descending colon?
Left colic artery and sigmoid arteries.
What artery supplies the sigmoid colon?
Sigmoid arteries.
What arteries supply the rectum and anal canal?
Superior rectal
- from IMA
- supplies anal canal until pectinate line
Middle rectal
- from internal iliac
Inferior rectal
- from internal pudendal
- supplies anal canal below pectinate line
What epithelium lines the large intestine?
Columnar absorptive cells
What is McBurney’s Point?
1/3 of a distance from umbilicus to right ASIS.
McBurney’s Sign - extreme tenderness over this region.
What is the lymphatic drainage of the large intestine?
Caecum and appendix - upper and lower ileocolic nodes
Asc and transverse colon - superior mesenteric nodes
Desc and sigmoid colon - inferior mesenteric nodes
