STOMACH:

The stomach is a  J-Shaped organ and the most dilated part of the gastrointestinal tract and is positioned between abdominal esophagus and small intestine. Stomach consists of cardia, fundus, body and pyloric antrum and pyloric canal. The lesser omentum is attached along the lesser curvature of the stomach, the greater omentum along the greater curvature. These omenta contain the vascular and lymphatic supply of the stomach.

When the stomach is used as a conduit in the chest, as in an esophagectomy, the left gastric, left gastroepiploic and short gastric vessels are divided, and the stomach then relies on the right gastric and right gastroepiploic vessels for viability. Ischemia does not usually result because of the free communication between the vessels supplying the stomach

Vascular supply: The arterial supply to the stomach is extremely rich and comprises:

• The left gastric artery from the coeliac axis;

• The right gastric artery from the hepatic artery;

• The right gastro-epiploic artery from the gastro-duodenal; a branch of the hepatic artery;

• The left gastro-epiploic artery from the splenic artery;

• The short gastric arteries from the splenic artery.

NERVE SUPPLY:

Nerves of stomach and duodenum are supplied intrinsic (myenteric, meissener's) and extrinsic

(sympathetic & parasympathetic) system. Parasympathetic supply is very important for the surgeon as it is the main stimulus for acid production from the parietal cells of the stomach, so transaction of this nerve can lead to inhibition of acid production.

The parasympathetic supply of the stomach is derived from the left and right vagus nerve. The left vagus forms the anterior trunk while the right vagus nerve forms the posterior trunk (mnemonic LARP: Left anterior Right posterior). 

The vagus nerve emerges from esophageal hiatus. Near the gastro esophageal junction the anterior vagus sends a branch to the liver and continues along the lesser curvature as the anterior nerve of Latarjet and posterior vagus sends a branch to the celiac axis. 

The nerves of Latarjet supply the body of the stomach and stimulate secretion of acid by the parietal cells. The nerve of Latarjet continues towards the antrum to end in a configuration known as crow's foot which innervates the antrum. The vagus trunk is also responsible for relaxation of the body of the stomach to accommodate ingested food and it also supplies the pyloric sphincter of the stomach.