Abdominal Neurovasculature

Question 1

What are the five branch groups of the Abdominal Aorta (AA)?

Answer 1

Ventral 
Lateral
Posterolateral
Posterior
Terminal

Question 2

Where does the AA start and how far does it run?

Answer 2

It runs from T12 to L4

Question 3

Name the Ventral branches of the AA.

Answer 3

Celiac Trunk (CT)
Superior Mesenteric Artery (SMA)
Inferior Mesenteric Artery (IMA)

Question 4

Name the Lateral branches of the AA.

Answer 4

Inferior Phrenic Artery

Arteries to 3 paired glands:

• Suprarenal
• Renal
• Gonadal (path differs based on gender of person it is found in)

Question 5

Name the Posterolateral branches of the AA.

Answer 5

Lumbar arteries (4 pairs)

Question 6

Name the Posterior branch of the AA.

Answer 6

Median Sacral artery

Question 7

Name the Terminal branches of the AA.

Answer 7

R&L Common Iliac arteries

Question 8

What are the branches of the Celiac Trunk?

Answer 8

Splenic artery (tortuous!)
Common Hepatic
Left Gastric

Question 9

At what point does the Common Hepatic artery become the Proper Hepatic artery?

Answer 9

After the Common Hepatic gives rise to the Right Gastric and Right Gastroduodenal branches.

Question 10

What vertebral level would you find the SMA?

Answer 10

L1 (1 inch below celiac trunk)

Question 11

What are the main (named) branches of the SMA? What do they supply?

Answer 11

Inferior Pancreaticoduodenal artery (head of pancreas, ascending/upper half of 2nd part of duodenum)

Middle Colic (proximal 2/3 of transverse colon)

Right Colic (ascending colon)

Ileocolic (terminal part of ileum, cecum, and vermiform appendix)
- APPENDICULAR ARTERY BRANCHES OFF OF THIS BAD BOY

(“IMRI”)

Question 12

How do you refer to the unnamed branches of the SMA?

Answer 12

Jejunal and Ileal branches

Question 13

What organs does the SMA provide blood supply to?

Answer 13

Large and Small intestine.

Question 14

What are the branches of the IMA? What do they supply?

Answer 14

Left Colic (distal 1/3 of transverse colon and descending colon)

Sigmoid (most superior branch of sigmoid = superior sigmoid artery)

Question 15

What does the IMA transition into once the final Sigmoid artery branches off it?

Answer 15

It becomes the Superior Rectal artery

Question 16

What organ does the IMA supply blood to?

Answer 16

Small Intestine only

Question 17

What do the Gonadal branches of the Lateral branch of AA supply blood to?

Answer 17

Testes and Ovaries

Question 18

Where does the Gonadal artery go in males? In females?

Answer 18

In males, the testicular artery runs laterally along pelvic inlet before entering between inguinal ligament and Sacro-Iliac joint around the pelvic inlet.

In females, the ovarian artery enters the true pelvis and goes into the suspensory ligament of the ovary, where it can supply the ovary and uterine tubes.

Question 19

The lumbar arteries are also known as?

Answer 19

Parietal arteries; they enter the wall.

Question 20

At what level does the AA end and bifurcate into the Common Iliac arteries? What happens to the External Iliac artery?

Answer 20

L4

The EIA becomes the Femoral artery after it passes under the inguinal ligament

Question 21

Where do the Common Iliac arteries branch into the External and Internal iliac arteries?

Answer 21

At the Sacroiliac Joint (SIJ) in the pelvic brim

Question 22

What are the surface markings of the AA?

Answer 22

From around 2.5 cm above the TPP in the midline to 1-2 cm below and to the left of the umbilicus, level with the intercristal plane.

Question 23

What is the venous drainage of the skin and superficial fascia of the abdomen ABOVE the umbilicus?

Answer 23

SVC via internal thoracic vein (medially) and lateral thoracic vein (laterally)

Question 24

What is the venous drainage of the skin and superficial fascia of the abdomen BELOW the umbilicus?

Answer 24

IVC via the inferior and superficial epigastric veins.

Question 25

How far does the IVC extend?

Answer 25

T8 to L5

Question 26

What neurovascular structure are the Lumbar arteries a part of?

Answer 26

VAN, like the bundle in the intercostal spaces.

Question 27

Where do the 1st and 2nd lumbar veins drain?

Answer 27

Ascending azygous system.

Question 28

What is the Cisterna Chyli?

Answer 28

Sac-like expansion at inferior end of the thoracic duct, and is usually absent. It receives lymph from the paired lumbar lymph trunks and intestinal lymph trunks fusing and contributing to the Cisterna Chyli.

Question 29

What supplies the somatic innervation of the abdominal region?

Answer 29

Thoracoabdominal nerves, L1 nerves of Lumbar Plexus, and Phrenic Nerve (specific structures only)

Question 30

What specific structures does the Phrenic nerve supply?

Answer 30

Diaphragm and 3P's Pleura Peritoneum Pericardium

Question 31

What supplies the innervation of the abdominal viscera?

Answer 31

The autonomic nervous system Parasympathetics are mostly delivered by CN X (Vagus). Pelvic Splanchnic Nerves innervate the distal 1/3 of the transverse colon to the rectum and proximal anal canal. Sympathetics are mostly supplied by preganglionic nerves whose cell bodies are located in lateral horn of T5 - L2/3 vertebrae. Their cell bodies are in the sympathetic chain, and they synapse at their prevertebral ganglia, which are Celiac, Mesenteric (Superior and Inferior), and Aorticorenal.

Question 32

What are the cases of venous blockage?

Answer 32

Caput Medusa | IVC obstruction

Question 33

How do you differentiate between the venous blockage types?

Answer 33

Press down on prominent vein. - If flow below umbilicus is toward legs = caput medusa - if flow below umbilicus is toward head = IVC obstruction

Question 34

What are the abdominal incisions?

Answer 34

Midline (linea alba) Para-median (along anterior wall of rectus sheath) McBurney (spino-umbilical line)

Question 35

Which incision is ideal and why? What incision do you have to be careful of and why? WHICH INCISION DO YOU JUST NOT DO?

Answer 35

Midline: quick access and no vasculature Para-median: take care to avoid cutting rectus muscle or innervation DON'T. DO. PARA. RECTUS.

Question 36

Differentiate between Visceral and Somatic pain.

Answer 36

Visceral: Diffuse and non-specific Somatic: Sharp and well-defined (specific)

Question 37

Between what vertebral levels will you feel diffuse visceral pain for foregut, midgut, and hindgut organs?

Answer 37

Foregut organs: T5-T9 Midgut organs: T10-T11 Hindgut organs: L1-L2

Question 38

What nerves are associated with the fore/mid/hindgut organs for pain?

Answer 38

Foregut: Greater Splanchnic Midgut: Lesser Splanchnic Hindgut: Lumbar Splanchnic (Symp) - Note: Pelvic Splanchnic is for parasympathetic of Hindgut