Evaluation and Management of Retroperitoneal Vascular Injuries

The abdominal aorta originates at the T12-L1 vertebra level as a continuation of the thoracic aorta.

It enters the abdomen through the aortic hiatus between the two crura of the diaphragm.

It bifurcates into the left and right common iliac arteries at the L4-L5 vertebra level.

The umbilicus is the external landmark for the bifurcation of the aorta.

Branches

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  Inferior phrenic arteries

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    Paired first branches of the abdominal aorta

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    Originates from the anterolateral surface of the abdominal aorta

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  Celiac trunk

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    Originates immediately below the phrenic arteries at the T12 vertebra level and is 1–2 cm in length

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    Located along the upper border of the pancreas

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    Branches

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      Common hepatic artery

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      Left gastric artery

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      Splenic artery

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  Superior mesenteric artery (SMA)

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    Located 1–2 cm below the celiac trunk posterior to the pancreas at the L1 vertebra level

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    Lies over the uncinate process of the pancreas and the third part of the duodenum and enters the root of the mesentery

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    Branches

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      Inferior pancreaticoduodenal artery

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      Middle colic artery

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      Arterial arcade with 12–18 intestinal branches

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      Right colic artery

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      Ileocolic artery

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  Renal arteries

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    Originate 1–1.5 cm below the SMA at the L2 vertebra level

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    Right renal artery

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      Located at a slightly higher level

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      Courses posterior to the inferior vena cava (IVC)

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  Inferior mesenteric artery (IMA)

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    Located 2–5 cm above the aortic bifurcation at the L3 vertebra level

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    Branches

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      Left colic artery

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      Sigmoid artery

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      Superior rectal artery

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    Communicates with the SMA through the marginal artery of Drummond

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  Subcostal arteries

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    Bilateral small arteries that originate from the posterior surface of the distal descending thoracic aorta

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    Courses beneath the 12th rib, it supplies to abdominal wall and also supply to the spinal cord

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  Middle suprarenal arteries

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    Middle suprarenal arteries originate from the posterior surface of the abdominal aorta at the level of the SMA.

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    Superior suprarenal arteries originate from the inferior phrenic arteries.

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    Inferior suprarenal arteries originate from the renal arteries.

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  Lumbar arteries

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    Four pairs of bilateral arteries on each side, originating from the posterior surface of the abdominal aorta

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    Located at the level of the corresponding upper four lumbar vertebrae

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    Supply to the muscles of the abdominal wall, skin, lumbar vertebrae, and spinal cord

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  Median sacral artery

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    Unpaired artery originates from the posterior aspect of the abdominal aorta just superior to the bifurcation

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    Supplies the fourth and fifth lumbar vertebrae, sacrum, coccyx, and super posterior rectum

Each common artery divides into the external and internal (hypogastric) iliac arteries.

The ureter crosses over the bifurcation of the common iliac arteries.

Continue as femoral arteries under the inguinal ligament

Branches

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  Inferior epigastric artery

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  Deep circumflex iliac artery

Divides into anterior and posterior branches at the level of the greater sciatic foramen

Branches from posterior division

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  Superior gluteal artery

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    Most common source of arterial bleeding in pelvic fractures

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    Gives rise to iliolumbar and lateral sacral arteries

Branches from anterior division

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  Superior vesical artery

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  Obturator artery

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  Inferior vesical artery

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  Middle rectal artery

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  Internal pudendal artery

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  Inferior gluteal artery

The IVC is formed at the level of L5 vertebra by the union of the common iliac veins posterior to the right common iliac artery.

The IVC enters the chest at the T8 verebra level through an opening in the diaphragm and drains in the right atrium.

Courses along the right side of the lumbar and thoracic vertebral bodies

The right crus of the diaphragm separates the IVC from the aorta.

Divided into:

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  infrarenal IVC—below the renal veins

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  retrohepatic IVC—usually 8–10 cm long

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  suprahepatic IVC—between the liver and the diaphragm and approximately 1 cm long

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  Intrathoracic (intrapericardial)

Branches

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  Lumbar veins

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    Usually five pairs

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    First pair of lumbar veins usually drain in the ascending lumbar veins on each side

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    Left lumbar veins pass behind the abdominal aorta.

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    Second, third, and fourth lumbar veins may drain directly to the IVC or the ascending lumbar veins on each side.

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    Fifth lumbar veins drain in the right common iliac vein on the right side and iliolumbar vein on the left side.

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    Ascending lumbar veins are connected to the IVC through lumbar veins.

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  Right gonadal vein

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  Left gonadal vein drains in the left renal vein.

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  Right adrenal (suprarenal) vein

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  Left adrenal (suprarenal) vein drains in the left renal vein.

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  Renal veins

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    Left renal vein is situated anterior to the aorta.

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    Renal veins lie anterior to the renal arteries.

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  Hepatic veins

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    Major veins: right, middle, and left hepatic veins

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    Many accessary veins: from the caudate and right lobes

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  Phrenic veins

Paired veins on each side of the lumbar vertebral body

Start from the common iliac veins

First pair of lumbar veins usually drain in the ascending lumbar veins on each side.

Second, third, and fourth lumbar veins may drain directly to the IVC or to the ascending lumbar veins on each side.

Arises as a continuation of the left ascending lumbar vein

Enters the left chest through the diaphragm

Connects to the azygos vein in the right chest at the level of T8 vertebra

Branches

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  Left 9th–11th intercostal veins

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  Left 12th intercostal (subcostal) vein

May connect to the left renal vein

Arises as a continuation of right ascending lumbar vein at the level of the right renal vein

Passes through the diaphragm and enters the right chest and drains in the superior vena cava (SVC)

Branches

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  Right 4th–9th intercostal veins

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  Right 12th intercostal (subcostal) vein

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  Hemiazygos vein

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  Accessory hemiazygos vein: Situated in the left posterior chest and drains left 4–8 intercostal veins

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  May have many anastomoses with IVC and vertebral venous plexuses

An important connection between the IVC and SVC for an alternate drainage in patients with IVC obstruction

Located posterior and to the right of the right common iliac artery

Branches

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  External iliac vein: Continuation of femoral vein

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  Internal iliac veins

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  Median sacral vein (or middle sacral vein): A branch of the left common iliac vein or sometimes arises from the angle of junction of the two iliac veins

Divides into anterior and posterior branches

Branches of posterior division

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  Superior gluteal vein

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  Iliolumbar and lateral sacral veins are the branches from the superior gluteal vein

Branches of anterior division

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  Obturator vein

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  Inferior gluteal vein

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  Internal pudendal vein

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  Vesical plexus

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  Rectal plexus

Blunt trauma in descending order

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  IVC

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  Aorta

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  Iliac arteries

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  Iliac vein

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  SMA

Penetrating trauma in descending order

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  Aorta

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  Iliac arteries

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  SMA

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  Renal arteries

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  Splenic artery

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  Celiac trunk

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  Hepatic artery

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  IMA