Abdominal Viscera 2

Question 1

Cecum

Answer 1

-Blind-ended pouch
-Covered in peritoneum, but no mesentery
-Contains ileo-cecal valve (1-way valve with ileum)

Question 2

Vermiform Appendix

Answer 2

-8-10cm long
-Aggregations of lymphoid tissue
-No longer necessary (more trouble than functional)
-Suspended by the mesoappendix (houses A/V)
-Variable positions: retrocecal, retrocolic, pelvic (pelvic and subcecal best positions for access, post. harder to access)

McBurney’s point= point on anterior abdominal wall that is the lateral 1/3 of distance from ASIS to umbilicus
-Dull pain and tender on palpation, inflamed= doctors visit, possible issue
-Sharp and intense pain= ambulance, life-threatening

Question 3

Colon (4 Parts + 2)

Answer 3

1. Ascending- right upper
2. Transverse
3. Descending- left upper
4. Sigmoid (pelvic)

*left colic flexure (splenic) and right colic flexure (hepatic)

Question 3

Colon 3 Features

Answer 3

1. Teniae coli/tenia
   -3 longitudinal bands of smooth muscle that run along outer layer of entire colon
2. Haustra/haustrum
   -Series of pouches in wall of the colon
   -Created by muscle tone in teniae coli
   -Permit expansion and elongation of colon
3. Epiploic appendages

Question 4

Peritoneal Coverings of the Colon: Mesocolon (3)

Answer 4

Complete Covering:
-Transverse and sigmoid mesocolons (intraperitoneal)

Partial Covering:
-Ascending, descending and rectal mesocolons (retroperitoneal)

Mesoappendix
-Connects appendix to ileum and cecum

Question 5

Large Intestine Blood Supply (3 Main, 3 Branches for Each of 2)

Answer 5

Superior mesenteric artery:
-Ileocolic
-Right colic
-Middle colic
*MRI (middle, right, ileocolic)

Inferior mesenteric artery:
-Left colic
-Sigmoidal
-Superior rectal (hemorrhoidal)
*I Love Singing Songs

Marginal artery of Drummond:
-Anastomoses b/t right, middle and left colic arteries, key for collateral circulation or alternative supply

Question 6

Large Intestine Venous Drainage

Answer 6

Splenic Vein:
-Hilum of spleen- posterior to tail and body of pancreas- join SMV
-Drains spleen, lower esophagus, part of stomach and pancreas

Superior Mesenteric Vein:
-Ascends in root of mesentery- pass ant. to 3rd part of duodenum (transverse)- joins splenic vein posterior to neck of pancreas
-Drains areas supplied by SMA (ileocecum, left colic, middle colic)

Inferior Mesenteric Vein
-Ascends on left posterior abdominal wall, join splenic vein posterior to pancreas
-Drains areas supplied by IMA (left colic, sigmoidal, superior rectal)

Question 7

Hepatic Portal Vein

Answer 7

-Splenic vein and superior mesenteric vein unite creating hepatic portal vein
-Carries nutrients from digestive tract to liver

-Portosystemic obstruction: result of obstructed venous return to liver, possibly causes= thrombosis, liver cirrhosis, heart failure