Describe the features and tributaries of the Superior Vena Cava (SVC)

Tributaries from R. and L.Brachiocephalic veins

• Brachiocephalic formed by tributaries of subclavian, internal jugular and internal thoracic veins
  • Subclavian tributary are external jugular veins

Single Azygous vein tributary

Begins in lower border of 1st costal cartilage and descends behind 2nd-3rd intercostal spaces into RA

L.Lateral border is aortic arch and trachea

R.Lateral border is pleura and right upper lobe of lung

Anterior border is thymus and manubrium

Describe the features and tributaries of the Inferior Vena Cava (IVC)

Formed by the joining of the common iliac veins at L5

Is a retroperitoneal structure - Posterior to abdominal cavity next to vertebral colum

Anastomoses the azygous system on the Right side of the vertebral column

Caval opening is at T8

Right side

• Gonadal vein and suprarenal vein drain into IVC

Left side

• Gonadal vein and suprarenal vein drain into renal vein then into IVC
• L.Inferior phrenic veins drain into L.Renal vein

All lumbar and hepatic veins drain into IVC

Tributaries from superior to inferior

• Hepatic - T8
• Inferior phrenic - T8
  • 1-2 per side from diaphragm
• R.Suprarenal - L1
• Renal - L1
• R.Gonadal - L2
• Lumbar - L1-5
• Common iliac - L5
  • Tributaries of internal and external iliac veins

Describe the epigastric veins, their tributaries and their relationship to the anterior abdominal wall

The veins accompany the arteries in the abdominal wall

Superior epigastric

• Drains into internal thoracic vein - inferior to external iliac vein

Both the superior and inferior anastomose with each other at the level of the umbilicus, and with paraumbilical veins

Inferior epigastric vein

• Arises from the superior epigastric vein
• Drains into external iliac vein

Describe the azygous system, its function and the relation to the SVC

The azygous or hemiazygous vein arise from the ascending lumbar vein from the lumbar veins and lateral sacral vein that come from the common iliac vein

• When these ascending lumbar veins cross the subcostal vein (vein along the bottom of the 12th rib) it becomes the azygous or hemiazygous

Comprises the azygous, hemiazygous, accessory hemiazygous and the L.superior intercostal vein

Function

• Drain the posterior abdominal wall, thoracic wall and the upper lumbar region via the lumbar and posterior intercostal veins

Azygous

• Arises from the union of the R.ascending lumbar and the R.subcostal vein ~T12
• Drains the R.lower 8 posterior intercostal veins and the R.bronchial veins
• Enters thorax via aortic hiatus
• Ascends along vertebral column on the RHS within the posterior mediastinum
• Arches over R.main bronchus T5-6
• Enters SVC at T4 or can enter into R.Brachiocephalic or R.subclavian
• Tributaries
  • Hemiazygous joins at T8 as it crosses from L. to R.
  • R.superior intercostal vein joins superiorly

Hemiazygous

• May or may not be present
• Arises from the L.ascending lumbar vein
• Passes through L.crus of diaphragm
• Drains L.9-11 posterior intercostal veins and L.subcostal vein
• Crosses vertebral column from L. to R. at T8 where it anastomoses with the azygous

Accessory hemiazygous

• Not always present
• On the LHS
• Arises from the 4th-8th L.posterior intercostal veins
• Drains L.bronchial vein
• Crosses behind the oesophagus at T8 to anastomose with the azygous or can anastomose superiorly to the L.brachiocephalic vein to join into the SVC

List all of the veins and their tributaries of the trunk (abdomen, thorax and neck region)

1. SVC
2. L. and R. Brachiocephalic
3. Internal Jugular
4. External Jugular
5. Subclavian
6. IVC
7. Hepatic veins
8. R. Suprarenal
9. R. gonadal
10. R. Renal
11. L. Suprarenal
12. L. Renal
13. L. Gonadal
14. Common iliac
15. Internal iliac
16. External iliac
17. Femoral
18. R.Ascending lumbar vein
19. Azygous
20. Hemiazygous
21. Accessory Hemiazygous
22. L.Ascending lumbar

Describe in brief the major drainage vessels of the 3 section of the gut (fore, mid and hind) via the hepatic portal system

Foregut ~ oesophagus, duodenum, stomach

• Drained by splenic vein
• Supplied by coeliac trunk

Midgut ~ Small intestine

• Drained by superior mesenteric vein
• Supplied by superior mesenteric artery

Hindgut ~ Large intestine

• Drained by inferior mesenteric vein
• Supplied by inferior mesenteric artery

Describe the relationship between surface/cross sectional anatomy and that truncal venous system

R.1st costal cartilage = Brachiocephalic veins become SVC

Manubriosternal joint = Azygous terminates at SVC

Transpyloric plane = Confluence of superior mesenteric and splenic veins

L5 = Common iliac veins joint o form IVC