(The clinical examination of the stomach contents is described under that heading).

Hypersecretion

Hypersecretion of gastric juice gives rise to thirst, sour eructations, more or less epigastric distress, and it often accompanies dilatation of the stomach. The secretion may digest proteids well, but carbohydrates are ill borne in this condition, which is believed to be chiefly caused by some form of neurosis. An excess of more or less acid gastric juice passes on with the chyme into the small intestine, and causes an acid reaction therein, requiring more of the intestinal digestive fluids - bile, pancreatic juice, etc. - to neutralise it. The saliva is often increased at the same time, and Roberts suggests that this may be a provision of Nature to neutralise the acid in the stomach.

Hyperacidity

Hyperacidity, or increase in the hydrochloric acid of the gastric juice, does not necessarily imply hypersecretion of juice. Hypersecretion may be abundant, watery, and weak in acid, or more concentrated with stronger acid, or normal in quantity but with increased hydrochloric acid.

Hyperacidity is common, and is especially apt to be present in connection with gastric ulcer and certain forms of chronic dyspepsia.

Absence Of Hydrochloric Acid

The persistent absence of hydrochloric acid from the gastric contents does not absolutely indicate the presence of any one disease, but rather that a considerable extent of the gastric mucosa is diseased, or it may be absent in nervous dyspepsia without organic lesion. This condition may exist with carcinoma.

Pyrosis

Pyrosis, or eructation of gas from the stomach, if it occurs very soon after ingestion of food, is usually due to lactic or other organic acid fermentation. Occurring later, during active digestion, it may be due to the same cause or to hyperacidity from excess of hydrochloric acid. The latter condition is less common when due to lactic acid; the giving of hydrochloric acid stops further fermentation, whereas sodium bicarbonate, although it momentarily neutralises the lactic acid, soon produces an alkaline reaction in which the further development of the acid rapidly proceeds. On the other hand, pyrosis due to hydrochloric acid must be checked by alkalies.