large intestine Flashcards
where does the large intestine begin? (inferior most part)
from the caecum
what follows from the caecum? (all the parts)
ascending colon, transverse colon, descending colon, sigmoid colon, rectum
what is the flow of the ascending colon?
from the caecum to the right lobe of the liver
where is the appendix located?
the mcburney point
how does the ileum and appendix connect?
the mesoappendix
what is contained in the mesoappendix?
the appendical vessels
what are the arteries of the appendix and caecum?
the superior mesentery artery that branches into the
1. anterior cecal branch of the ileocolic artery
2. posterior cecal branch of the ileocolic artery
3. appendicular artery of the ileocolic artery
what are the venous drainages of the ascending colon?
the right colic vein and the iliocolic vein
where does the ascending colon end?
the hepatic/right colic flexure
what are the peritoneal pouches in the large intestine?
the omental appendices
what is located anteriorly to the ascending colon?
SIGMA
1. small intestine
2. greater omentum
3. anterior abdominal wall
what is located posteriorly to the ascending colon?
- iliohypogastric and ilioinguinal nerves
- the right kidney
- the iliacus and quadratus lumborum
what is the flow of transverse colon?
from the hepatic flexure to the splenic flexure
what is the vascularization of the ascending colon?
branches of the superior mesentery artery:
1. anterior cecal branch of the ileocolic artery
2. posterior cecal branch of the ileocolic artery
3. right colic artery of the superior mesentery artery
4. colic branch of the ileocolic artery
what is the vascularization of the transverse colon?
branches of the SMA and IMA
1. middle colic artery
2. left colic artery (from IMA)
what is the venous drainage of the transverse colon?
it drains to the
1. middle colic vein
2. left colic vein
what is the splenic flexure and how does it differ from the hepatic flexure?
it is located more posteriorly and it is more acute
what is the flow of the descending colon?
from the splenic flexure to the descending colon-sigmoid junction
what is the vascularization of the descending colon?
- the left colic artery
- the superior sigmoid artery
what is located anteriorly to the descending colon?
- the small intestine
- the greater omentum
- the anterior abdominal wall
what is located posteriorly to the descending colon?
- the left kidney
- the ilioinguinal and iliohypogastric nerve
- the iliacus and the quadratis lumborum
what is located anteriorly to the transverse colon?
- the greater omentum
- the anterior abdominal wall
what is located posteriorly to the transverse colon
- duodenum
- jejunum
- ileum
- the head of the pancreas
where is the caecum located?
in the true pelvis
how is the sigmoid colon formed?
medial protrusion of the descending colon
what is on the anterior of the sigmoid colon?
the ureter, urethra, upper vagina (for women)
what is on the posterior of the sigmoid colon?
the rectum, ileum, and sacrum
what is the rectum formed by?
the taenia coli
where does the rectum begin?
from the S3
is the rectum retroperitoneal or intraperitoneal?
retroperitoneal
what are the muscle fibers of the taenia coli?
- taenia libera
- taenia mesocolic
- taenia omental
what is the marginal artery? what is it also called?
the anastomosis of the superior and inferior mesentery artery
what are the lymphatics of the large intestine?
ascending and transversal: superior mesentery lymph nodes
descending and sigmoid:
inferior mesentery lymph nodes
where do the secondary lymph nodes eventually drain to?
the cisterna chyli
what are the innervations of the midgut?
the superior mesenteric plexus
what are the innervations of the hindgut?
the inferior mesenteric plexus (the sympathetic lumbar splanchnic nerve and the parasympathetic sacral splanchnic nerve)
what is the vascularization of the rectum?
- superior rectal artery
- middle rectal artery (internal iliac artery)
- inferior rectal artery (internal pudendal artery)
what causes appendicitis?
obstruction from fecal matter and enlargement of lymph
how does appendicitis break the wall of the appendix?
by necrotizing it, the walls may break and perforate to other areas
how would you explain the colic and focal pain caused by early and late appendicitis?
colic pain is caused by visceral sympathetic nerve of T10 that causes colic (diffusive) pain on the periumbilical region
focal pain results from perforation of inflammation to the parietal peritoneum of the iliac fossa that is innervated by the respective somatic nerve
what may arise as complications of appendicitis?
transmural inflammation (it spreads all over the bowel’s wall)
peritonitis
phlegmon
necrotizing fasciitis
what is the avascular part of the large intestine?
the inferior iliocaecal fold or the bloodless fold of Treves
True or false?
The normal BP of portal vein is 8-10 mmHg!
False, it’s 6-12 mmHg
