Blood and Nerve Supply to Abdominal Organs

Question 1

abdominal aorta

Answer 1

begins at T12
retroperitoneal
terminates at L4

Question 2

relationships of the abdominal aorta

Answer 2

IVC lies to the right of aorta
L renal v. crosses anterior to the aorta
anterior longitudinal lig. and vertebral bodies are posterior
thoracic duct and cisterna chyli is to the right
duodenum, pancreas, and root of mesentery all cross anterior surface of the aorta

Question 3

abdominal aortic aneurysm AAA

Answer 3

ballon like dialation of the abdominal aorta
usually arises below the renal a and above the aortic bifurcation
primarily due to atherosclerosis
presents as pulsatile abdominal mass that grows with time
aorta should be no larger than 3 cm on palpation
major complication is rupture

Question 4

Foregut

Answer 4

Nerve plexus - celiac
Artery - celiac
PNS - vagus
Vertebral Level - T2-L1
SNS - T5-T9, greater splanchnic n. 
Structures - stomach 1st and 2nd part of duodenum, liver, gallbladder, pancreas, spleen

Question 5

Midgut

Answer 5

Nerve plexus - SM
Artery - SMA
PNS - vagus
Vertebral Level - L1
SNS - T10- T11, lesser splanchnic n. 
Structures - 3rd and 4th part of duodenum to proximal 2/3 of transverse colon

Question 6

Hindgut

Answer 6

Nerve plexus - IM
Artery - IMA
PNS - Pelvic splanchnic
Vertebral Level - L3
SNS - T12- L2, least splanchnic n. 
Structures - distal 1/3 of transverse colon to upper portion of rectum

Question 7

Celiac Trunk

Answer 7

branches at T12-L1
3 branches - L gastric, splenic, common hepatic
base of a surrounded by celiac plexus and ganglion

Question 8

Left gastric a

Answer 8

gives off esophageal branches
follow lesser curvature of stomach
anastomoses w/ R gastric a along the lesser curvature

Question 9

Splenic a

Answer 9

runs posterior to stomach, superior to the pancreas
very tortuous
within splenorenal ligament
ends as several splenic a
branches - short gastric a, L gastro-omental a, panceatic branches

Question 10

Common hepatic a

Answer 10

Proper hepatic

Gastroduodenal a.

Question 11

Proper hepatic a

Answer 11

R gastric a
ends as R and L hepatic a
cystic a is usually a branch

Question 12

Gastro-duodenal a

Answer 12

may give off supraduodenal a
runs posterior to duodenum
bifurcates into R gastro-omental a and superior pancreaticoduodenal a

Question 13

Relationship of portal triad

Answer 13

proper hepatic a - left
portal vein - posterior
bile duct - right
surrounded by hepatoduodenal ligament

Question 14

cholecystectomy

Answer 14

dissection is through hepatoduodenal ligament to reach the cystic a which must be ligated before removing the gall bladder

Question 15

Calot’s triangle

Answer 15

medially - common hepatic duct
laterally - cystic duct
superiorly- edge of liver
cystic a crosses the middle of the triangle
calot’s node - main route of lyphatic drainage of gallbladder

Question 16

Superior Mesenteric a

Answer 16

1 cm inferior to celiac trunk

emerges from aorta posterior to the neck of the panceas

Question 17

Blood supply to the pancreas and duodenum

Answer 17

pancreas receives branches from both the celiac and superior mesenteric arteries
celiac - superior pancreaticoduodenal
SMA
anastomosing arcades b/w SMA and gastroduodenal

Question 18

Superior Mesenteric a

Answer 18

supplies branches to the free small intestine and part of large intestine
emerges from the aorta posterior to the neck of the pancreas, to the left of the SMV, enters THE mesentery and runs b/w its layers to reach the ileum and jejunum

Question 19

SMA branches to small intestine

Answer 19

inferior pancreatico-duodenal a
jejunal arteries
ileal arteries

Question 20

SMA branches to large intestine

Answer 20

ileocolic a
R colic a
Middle colic a

Question 21

Ileocolic a

Answer 21

posterior cecal branch 
anterior cecal branch 
ileal branch
appendicular branch 
ascending colic branch

Question 22

R colic a

Answer 22

ascending colon

R colic flecure

Question 23

middle colic a

Answer 23

supplices R colic flecure and transverse colon

Question 24

IMA

Answer 24

supplies derivaties of hindgut

branches - left colic a, sigmoid a, superior rectal a, margial a

Question 25

Superior rectal a and v

Answer 25

drain to IMV

Question 26

Middle rectal a and v

Answer 26

drain to internal iliac v

Question 27

inferior rectal a and v

Answer 27

drain to internal pudendal v

Question 28

Sympathetic innervation

Answer 28

preganglionic fibers arise at T5-L1
travel in respective splanchnic n
synapse in prevertebral sympathetic ganglia
postganglionic fibers travel from ganglia to abdominal organs

Question 29

Parasympathetic innervations

Answer 29

preganglionic fibers travel through celiac plexus but do not synapse, synapse in n plexi of enteric (intrinsic) nervous system contained in gut wall
supplied by vagus and pelvic n
vagus innervates the foregut and midgut
pelvic n arise at S2-S4 innervate hindgut

Question 30

Enteric nervous system

Answer 30

composed of a series of ganglionic nerve plexi contained within the gut wall
two principal components
Myenteric (Auerbach’s) plexus
Submucosal (Meissner’s) plexus

Question 31

Myenteric (Auerbach’s) plexus

Answer 31

between outer longitudinal and inner circular muscle layers

motility

Question 32

Submucosal (Meissner’s) plexus

Answer 32

secretions blood flow absorption

Question 33

Hirschsprung Disease

Answer 33

failure of neural crest cells to migrate during intestinal development
no myenteric plexus (need to take some muscularis mucosa)
neural crest cells become the enteric ganglion cells
no PNS so the gut cannot relax causing constriction and megacolon of the proximal colon segments
most cases occur in the rectosigmoid junction
down syndrome babies have higher risk

Question 34

chagas disease

Answer 34

megacolon

T. cruzi destroys autonomic nervous system mainly myenteric plexus