Blood vessels of the abdomen and pelvis
As the abdomen and pelvis contain the majority of internal organs, these regions need to be supplied by an extensive network of arteries and veins. That being said, all arterial blood delivered to this region comes via branches of the abdominal aorta, and all venous blood eventually finds its way back to inferior vena cava (IVC).
You can imagine the aorta and IVC as the two trees, with all the abdominopelvic vessels ramifying from them. At this point, learning all those branches may seem like a vexing thing to do. For that reason, this page will present them in a systematic and student-friendly manner so that you can learn them once and for all.
|Arterial supply||Parietal and visceral branches of the abdominal aorta|
|Venous drainage||Inferior vena cava
*stomach, intestines, pancreas and spleen first drain to the liver via the hepatic portal vein
|Abdominal aorta branches||
Visceral: celiac trunk, superior mesenteric artery, middle suprarenal arteries, renal arteries, gonadal arteries, inferior mesenteric artery
Parietal: inferior phrenic artery, lumbar arteries, median sacral artery
Terminal: common iliac arteries
|Inferior vena cava tributaries||Lumbar veins, right gonadal vein, renal veins, right suprarenal vein, inferior phrenic veins, hepatic veins|
This article will discuss the anatomy of abdominal arteries and veins, as well as topographical approach to the abdominopelvic vasculature.
- Abdominal aorta
- Inferior vena cava
- Abdominal wall
- Small and large intestines
- Liver and gallbladder
- Reproductive organs
The abdominal aorta is a continuation of the thoracic aorta, once it has traversed the aortic hiatus of the diaphragm. As it supplies just about everything in the abdomen and pelvis, it is a large caliber artery, and is as wide as a garden hose (~25mm) and gives numerous branches.
The course of the abdominal aorta is quite simple. After passing through the aortic hiatus (T12), it descends slightly to the left of the lumbar vertebrae, with the inferior vena cava being just right to it. The aorta terminates at the L4 level by bifurcating into left and right common iliac arteries.
There are 10 major branches of the abdominal aorta. We can sort them by what part of the abdomen and pelvis they supply into visceral (organs), parietal (abdominal walls) and terminal branches.
We’ve created a diagram with major branches of the abdominal aorta to ease up your straight recall practice.
Don’t get petrified if you have realized that the aorta has more branches than you initially anticipated. Once we break things down and look at the blood supply organ by organ, it will all sort nicely in the end.
If you still feel overwhelmed by so many branches of the aorta, check out these 4 steps to memorize anatomical terms which will make your study process a lot more efficient.
Inferior vena cava
The inferior vena cava (IVC) is the headmaster of the veins department. It collects all the blood from the abdomen, pelvis and lower limbs and carries it to the right atrium of the heart. The IVC is formed by merging of the left and right common iliac veins at the L5 vertebral level, just in front of the aortic bifurcation.
The inferior vena cava then ascends to the right of the abdominal aorta along the vertebral column, receiving blood from numerous tributaries, and eventually passing through the caval foramen of the diaphragm. Notice that the veins draining the organs of gastrointestinal tract do not empty into the inferior vena cava. This is important to remember! Continue reading below to find out more about their venous drainage.
Hepatic portal vein
The hepatic portal vein is a vein that receives all the venous blood from the stomach, small and large intestines, pancreas and spleen. It arises at the confluence of the superior mesenteric and splenic veins, just posterior to the neck of the pancreas. It passes through the porta hepatis together with the hepatic artery and bile duct as it enters the liver. Once processed and detoxified through the liver, the venous blood delivered by the hepatic portal vein leaves the liver via the hepatic veins, which empty into the inferior vena cava.When there is an obstruction of the portal system e.g. due to cirrhosis of the liver, blood can be shunted away from the liver to systemic veins through portosystemic anastomoses. These occur between vessels which feed into the portal vein and nearby systemic veins e.g. splenic vein to left renal vein. This helps to reduce portal venous pressure during portal hypertension. Although this is useful for a short period of time, bypassing the liver may be dangerous, as that means foregoing the detoxification process.
Now that we understand the beginning (abdominal aorta), and the end (inferior vena cava) of the abdominopelvic circulation, let’s fill the gaps in between by looking the supply and drainage of the different parts of this region, beginning first with the abdominal wall.
Arterial supply of the abdominal wall comes from the following:
- Superior epigastric artery, a branch of the internal thoracic artery
- Inferior epigastric artery, a branch of the external iliac artery
- Superficial circumflex iliac and superficial epigastric arteries, the branches of the femoral artery
- 10th and 11th intercostal arteries and the subcostal artery
- Lumbar arteries, branches of the abdominal aorta
The venous drainage follows a similar pattern:
- Superior epigastric vein, a tributary to the internal thoracic vein
- Inferior epigastric and deep circumflex iliac veins, the tributaries to the external iliac vein
- Superficial circumflex iliac and superficial epigastric veins, the tributaries to the femoral and greater saphenous veins
- 10th and 11th intercostal veins and the subcostal vein
- Lumbar veins, tributaries to the inferior vena cava
The stomach is supplied by the branches of the celiac trunk, which include the right and left gastric, right and left gastro-omental, short gastric and posterior gastric arteries. Venous blood is conveyed by the right, left and short gastric, prepyloric, right and left gastro-omental veins. They all empty into the system of the hepatic portal vein.
Small and large intestines
The intestines have very rich blood supply. Put simply, they are supplied and drained by the branches of three primary vessels: the celiac, superior and inferior mesenteric vessels. Let’s take a closer look into that.
Vessels of the small intestine are grouped by which segment they supply:
- The duodenum is supplied by the superior and inferior pancreaticoduodenal arteries, which are the branches of the gastroduodenal and superior mesenteric arteries, respectively. Venous drainage occurs via the prepyloric, superior pancreaticoduodenal and inferior pancreaticoduodenal veins, which are and drained by the superior mesenteric and hepatic portal vein.
- The jejunum and ileum are supplied by the jejunal and ileal arteries, and drained by their venous counterparts, the jejunal and ileal veins (tributaries of the superior mesenteric vein).
The segmental approach to vasculature applies to the large intestine as well:
- The cecum is supplied by the ileocolic artery, and drained by the ileocolic vein.
- The ascending colon is supplied by the ileocolic and right colic arteries (both branches of the superior mesenteric artery), and is drained by their venous counterparts, the ileocolic and right colic veins.
- The proximal two-thirds of the transverse colon are supplied by the middle colic artery (of superior mesenteric artery) and while the distal third receives its arterial supply via left colic artery (of inferior mesenteric artery). Both segments of the transverse colon are drained by the venous equivalents of the these arteries, which empty into the superior mesenteric and inferior mesenteric veins, respectively.
- The descending and sigmoid colon are supplied by the left colic and sigmoid arteries, which are branches of the inferior mesenteric artery. Venous blood is drained via veins of the same name which empty into the inferior mesenteric vein drains.
- The rectum and anal canal recieve arterial blood from the superior, middle and inferior rectal arteries. The venous blood is conveyed through the superior, middle and inferior rectal veins.
As you know, the peritoneum consists of the parietal and visceral peritoneum. The parietal peritoneum is supplied by the vessels of the abdominal wall. The visceral peritoneum is supplied by its associated viscera. So if we know that the intraperitoneal organs are the liver, spleen, stomach, superior part of the duodenum, jejunum, ileum, transverse colon, sigmoid colon and superior part of the rectum, we then know that their vessels supply the adjacent peritoneal formations.
Liver and gallbladder
Let’s see what supplies the liver, our detox center. The tissue of the liver is supplied by the hepatic artery, which is a branch of the celiac trunk. Interestingly, the blood delivered by the hepatic artery only represents one quarter of the total blood volume received by the liver. The other three quarters of the blood delivered to the liver come from the hepatic portal vein. Venous blood is drained by the hepatic veins, which empty into the inferior vena cava.
The biliary system, which consists of intra- and extrahepatic biliary ducts as well as the gallbladder, is supplied by several vessels:
- Intrahepatic biliary ducts are supplied by the branches of the hepatic artery, and drained by the hepatic veins.
- The common bile duct is supplied by the cystic artery, right hepatic artery, superior pancreaticoduodenal and gastroduodenal arteries. The hepatic veins and superior pancreaticoduodenal vein drain the common bile duct.
- The gallbladder is supplied by the cystic artery, and drained by the cystic vein.
The pancreas is supplied by the pancreatic branches of the splenic, gastroduodenal and superior mesenteric arteries (SMA).
The splenic artery gives off several pancreatic branches which supply the body and tail of the pancreas. The gastroduodenal artery gives off the superior pancreaticoduodenal artery, whereas the superior mesenteric artery provides the inferior pancreaticoduodenal artery; these deliver arterial blood to the head of the pancreas. The pancreas is drained by the pancreatic and pancreaticoduodenal veins, which empty into the splenic, superior mesenteric and hepatic portal veins.
Reproductive organs in both sexes are supplied by branches of the gonadal (testicular or ovarian) and internal iliac vessels.
Concerning the blood supply of the male pelvis, here are the must-know facts:
- The ductus deferens (formerly known as the vas deferens) is supplied by the superior vesical artery and drained by the testicular vein.
- Seminal glands are supplied by the inferior vesical and middle rectal arteries, and drained by the middle rectal veins.
- The prostate is supplied by the inferior vesical, internal pudendal and middle rectal arteries. It is drained by the prostatic venous plexus which empties into the internal iliac vein.
- The testes are supplied by the testicular arteries, and drained by the pampiniform venous plexus. Testicular veins emerge from the plexus, with the right testicular vein emptying into the IVC, and the left into the left renal vein.
- The penis is supplied by the branches of internal and external pudendal arteries, while it is drained by the deep dorsal vein of the penis, a tributary to the internal pudendal vein.
There are several facts you should remember about the female pelvis blood supply:
- The ovaries are supplied by the ovarian arteries, and drained by the pampiniform venous plexus which empties into the ovarian vein. Note that the right ovarian vein empties to the IVC, whereas the left empties into the left renal vein.
- The uterus is supplied by the uterine arteries and drained by the uterine veins.
- The vagina is supplied by the uterine, vaginal and internal pudendal arteries. It is drained by the vaginal venous plexus.