Stomach

The stomach is a muscular organ located in the left side of the upper abdomen
It is a food reservoir and it can hold upto 1 litre of food
The main function of stomach is food digestion (Breaking a large insoluble food molecules into smaller soluble food molecules)
Digestion in the stomach involves both mechanical and chemical digestion
- Mechanical digestion
  - Contractions of smooth muscle of stomach lead to mixing and grinding of food resulting in smaller food particles
- Chemical digestion
  - Stomach glands secret enzymes (pepsin) & hydrochloric acid and with the help of acid and enzymes, food particles are further digested to form a thick liquid food known as chyme
Finally, the chyme is periodically emptied into the duodenum through pyloric sphincter for further digestion and absorption in the small intestine
Solid food emptying time is 3-4 hours and liquid food emptying time is around 30 minutes
Although the main function of stomach is food digestion and not absorption, there are few substances which are absorbed in stomach
- Water in case of dehydration
- Drugs such as aspirin
- 10–20% of ingested alcohol etc.

Common disorders of stomach

Dyspepsia
- It is a commonest problem characterised by variety of symptoms including nausea, bloating after meals, pain, discomfort etc.
Gastroesophageal reflux disease (GERD)
- Stomach contents, including acid, may reflux upwards into the esophagus occasionally which is a normal phenomenon in healthy people
- However, when the reflux becomes more frequent & bothers the patient it is called as GERD
Gastritis
- It is the inflammation of the stomach characterised by nausea and/or pain
- It can be caused by drugs (NSAID's), alcohol, H. pylori infection, etc.
Gastric ulcer
- An erosion or break in the continuity of gastric mucosa (inner lining) characterised by pain, especially after meals and bleeding sometimes.
- Gastric ulcers can be benign (peptic ulcer) or malignant
Stomach or gastric cancer

Upper GI Endoscopy (UGIE)
- A flexible fibre optic tube with a camera on its end (endoscope) is inserted through the mouth. The endoscope allows examination of the esophagus, stomach, and duodenum
- Biopsy if necessary can be taken
- Endoscopy can be both diagnostic & therapeutic
Computed tomography (CT scan)
- Mainly to evaluate gastric tumors
Magnetic resonance imaging (MRI)
Barium meal
- It is the x ray taken after swallowing radio opaque material such as barium sulfate
- It delineates contour of the stomach

Dyspepsia, GERD, Gastritis and Gastric ulcers
- Acid suppressing drugs such as PPI (Proton Pump Inhibitors), H2 blockers, antacids and motility agents
Therapeutic Endoscopy
- For eg- variceal banding for bleeding, stricture dilatation & stenting etc.
Anti H.Pylori drugs for H.Pylori infection
Gastric surgeries
- D2 Gastrectomy ( Partial or Total) for Gastric cancers
- Vagotomy for ulcers
- Gastro-jejunsotomy for obstruction
- Bariatric Surgeries for obesity ( Laparoscopic sleeve gastrectomy, Laparoscopic RYGJ, Laparoscopic MGB (Mini Gastric Bypass) etc.