The coeliac trunk and the blood supply of the upper abdomen

1. Start with the aorta

The abdominal aorta runs down on the front of the vertebral bodies, slightly to the left of the midline. The inferior vena cava runs beside it on the right. Every gut artery comes off the front of the aorta as an unpaired vessel.

Surgeon’s corner: Three unpaired gut arteries leave the front of the aorta, from top to bottom: coeliac trunk (foregut), superior mesenteric artery (midgut) and inferior mesenteric artery (hindgut). Remember: one gut segment, one artery.

2. The coeliac trunk

Just below the aortic opening of the diaphragm, at the level of T12–L1, a short fat trunk leaves the front of the aorta: the coeliac trunk. After only 1–2 cm it splits into three branches, like a tripod.

Surgeon’s corner: The median arcuate ligament of the diaphragm can compress the trunk (median arcuate ligament syndrome: post-prandial pain, weight loss). In a pancreatoduodenectomy you must know whether the liver depends on collaterals from the gastroduodenal artery before you tie it.

3. Branch 1: left gastric artery

The smallest branch runs up and to the left, to the lesser curvature of the stomach near the oesophagus. It gives oesophageal branches and then runs down along the lesser curvature.

Surgeon’s corner: Bleeding gastric ulcers on the lesser curvature erode branches of the left gastric artery. In a gastrectomy it is divided at its origin, with the surrounding lymph nodes (station 7).

4. Branch 2: splenic artery

The largest branch runs to the left along the upper border of the pancreas, often very tortuous. On its way it feeds the pancreas, gives the short gastric arteries to the fundus and the left gastro-omental artery along the greater curvature, and ends in the spleen. The splenic vein runs behind the pancreas, below the artery.

Surgeon’s corner: Splenic artery aneurysms are the commonest visceral aneurysms (risk of rupture in pregnancy). In a distal pancreatectomy or splenectomy you control the splenic artery first, along the top of the pancreas.

5. Branch 3: common hepatic artery

The third branch runs to the right above the pancreas and divides into the gastroduodenal artery, which dives behind the first part of the duodenum, and the proper hepatic artery, which climbs to the liver.

Surgeon’s corner: A posterior ulcer of the duodenal bulb erodes straight into the gastroduodenal artery: massive upper GI bleeding. If endoscopy fails, the surgeon under-runs the vessel through the opened duodenum.

6. Into the liver: the hepatoduodenal ligament

The proper hepatic artery runs up in the free edge of the lesser omentum together with the bile duct (to the right, in front) and the portal vein (behind). These three are the portal triad. Near the liver the artery divides into right and left hepatic arteries; the cystic artery to the gallbladder usually comes from the right hepatic artery.

Surgeon’s corner: Pringle manoeuvre: a clamp across the free edge of the lesser omentum stops inflow to the liver in major bleeding. In cholecystectomy, the right hepatic artery can loop into Calot’s triangle (caterpillar hump): another reason to achieve the critical view of safety before clipping.

7. A look below: the superior mesenteric artery

About 1 cm below the coeliac trunk the superior mesenteric artery leaves the aorta behind the neck of the pancreas, crosses in front of the third part of the duodenum and supplies the midgut. The pancreatic head lives on arcades between the two systems (pancreaticoduodenal arteries).

Surgeon’s corner: Variants matter: in about 15% the right hepatic artery arises from the superior mesenteric artery (replaced right hepatic artery) and runs behind the bile duct, where it is easily injured during a Whipple or cholecystectomy.