Gastrointestinal tract

“ Acute Enteritis, as Acute Gastritis, is usually caused by a strong irritant,—either by some food which disagrees, or by a mass of undigested food. A fast of two or three days is the initial dietetic treatment. A free drinking of water not only soothes the irritated intestines but it cleanses the intestinal tract and assists the kidneys in eliminating elements of fermentation ”

“ Ruminating animals, or animals which chew the cud, such as the Cow, have several stomachs, and the food undergoes mastication several times, at each time being passed into a different stomach, before being finally acted upon by the gastric juice, after which it is transmitted through a long tract of intestines. This is an example of the most complex 360 digestive organ fitted to act upon hard and fibrous food, which must be subjected to the action of several menstrua preparatory to its being acted upon by the gastric juice. ”

“ The chronic ulceration, the scarring, thickening, and contractions of the gut are irremediable conditions which too often, after months or years of suffering, lead to intestinal obstruction or, very frequently, to atrophy of the glandular and absorbent system of the entire alimentary tract, general wasting, and fatal asthenia. Such patients hardly ever pass a healthy motion; they are troubled with chronic indigestion; at times they pass their food unaltered; they have recurring attacks of diarrhœa ”

“ I have never dissected the stomach of a drunkard, in which the organ did not manifest some remarkable deviation from its healthy condition. But the derangement of the stomach is not limited to the function of nutrition merely. This organ is closely united to every other organ, and to each individual tissue of the body, by its sympathetic relations. When the stomach, therefore, becomes diseased, other parts suffer with it. The functions of the brain, the heart, the lungs, and the liver, become disordered ”

“ It is no trifling matter to have the function of some thirty feet of the gastro-intestinal tract disturbed, especially of the large intestine—some five feet in length, two and a half inches in diameter in not a few sections. ”

“ Too much attention cannot be given to the question of hygiene, diet, and excretion to meet the psycho-physical requirements of the mind and body in normal health. As a rule, diet is prescribed for the purpose of relieving the various annoying and painful symptoms caused by chronic impairment of the functions of the stomach and bowels, but when we find the cause of these various symptoms arising from a disturbed gastro-intestinal tract, the question of diet will receive less attention. ”

“ The sphincter between the stomach and small intestine is operated by hydrochloric acid, making up a remarkably ingenious arrangement for securing the emptying of the stomach as fast as the food is ready to be passed on into the small intestine. In order that gastric digestion may have full opportunity, it is necessary that the food should be thoroughly mixed with the gastric juice. ”

“ The lack of a sufficiently vigorous flow of blood is followed by deficient secretion of digestive agents from the glandular elements involved, by decreased motility of the muscular coats of the stomach and bowel, and lessened adaptability throughout for dealing with even slight irregular demands on their powers. ”

“ Gastric juice is secreted continuously, but quantities sufficiently large for examination are not usually obtainable from the fasting stomach. In clinical work, therefore, it is desirable to stimulate secretion with food—which is the natural and most efficient stimulus—before attempting to collect the gastric fluid. Different foods stimulate secretion to different degrees ”

“ Hitherto we have been accustomed to regard the phases of digestion, gastric digestion, pancreatic digestion, and intestinal digestion, as almost separate processes, any of which we might increase indefinitely without doing any harm to the patient. We forget the relation which each bears to the other; and yet such a relation undoubtedly exists, for we find that when pepsin is mixed with bile it is precipitated and rendered inert. Further transformation of foods by the gastric juice is thus arrested as soon as the chyme leaves the stomach. ”

“ Solid food given to the child before it has cut its teeth, enters the stomach unreduced to pulp by the grinders, and unmixed with the saliva, which should help its solution, and which the undeveloped salivary glands do not yet furnish. Too large a quantity of food, or food of an unsuitable character, on which the gastric juice cannot act readily, may pass into a state of fermentation; vomiting, flatulence, sour and offensive breath will be the result, and the food will pass into the intestine unprepared to be acted on by the bile. ”

“ Experience shows that the delicate stomach suffers severely from these causes. In some instances, the long unemployed organ secretes an excess of mucus, which greatly interferes with digestion. A sufficient amount of food at breakfast has a direct influence on the digestion of dinner; in which process, large quantities of gastric juice—a fluid charged with nitrogenous and other materials—must be suddenly extracted from the blood. ”

“ It acts as a digestive organ of importance in preparing the food for further attack in the intestinal canal. But the stomach cannot be regarded as an essential organ, since it has been removed in dogs and in man without apparent interference with nutrition and health. Gastric digestion is brought about by the action of the gastric juice, a clear watery, colourless and strongly acid fluid with a specific gravity of about 1003. ”

“ Intestinal Digestion.—The chemical changes which food undergoes in the small and large intestines are exceedingly complex. Digestion in the intestine is due to the combined action of the bile, pancreatic juice, and succus entericus. The material which enters the duodenum from the stomach is known as the chyme. The acid chyme provokes a flow of bile and pancreatic juice. It acts upon the prosecretin in the duodenal mucous membrane in such a manner that secretin, a hormone, is formed and carried by the blood to the cells of the pancreas which it stimulates. ”

“ From the important and complex function of the intestinal juices, and the very great share they take in the solution of food, there must be many phases of departure from the normal state. The processes of intestinal digestion are more intricate than those of gastric digestion, of a higher grade, and the chemical reactions are more numerous, depending upon the participation of the bile, the pancreatic juice, and the succus entericus; while intestinal absorption is a more complex act than that of gastric absorption. ”

“ HOW AUTO-INFECTION AFFECTS THE GASTRIC DIGESTION, AND VICE VERSA.
Frederick the Great said that all culture comes through the stomach. This saying emphasizes pithily the dependence of psychology upon physiology. The stomach with the intestines is certainly the source from which every portion of the body receives its nourishment and most of its diseases. The physiological plus and minus processes leave their reflex on the mind. ”

“ The large intestines are easily cured, but the small ones with difficulty, and the jejunum is utterly incurable, from the multitude of its convolutions and the magnitude of its vessels, and owing to its coats being thin and nervous; besides, it receives all the bile in an undiluted state, and is nearest to the liver. The under and fleshy parts of the stomach we may attempt to cure, for we may succeed, not only because these parts are thicker, but because curative medicines are more readily applied to them, owing to their situation. ”

“ In a state of health the abundantly secreted gastric juice speedily redissolves the chief part of the curd in the stomach, while when it has passed into the intestine the alkaline bile which there becomes mixed with it, completes its solution, and converts the whole into a fluid which closely resembles one of the chief elements of the blood, is consequently very easily taken up by the minute vessels whose office it is to do so, and thus supplies with nourishment the whole body. ”

“ Only in our own day has come the greatest confirmation of the notion then first introduced into physiology, of the surpassing importance of intestinal digestion. The removal of the whole stomach for malignant disease is now undertaken without any fears as to the ultimate result on the patient's general nutrition. The operation has been done many times, and the surgeon's confidence that the intestines would compensate, as far as digestion of food was concerned, for the absent stomach has been amply justified. ”

“ The small intestine commences at the pylorus, winds into many convolutions, and terminates in the large intestine. In the adult it is about 20 feet in length. It is arbitrarily divided into three parts—viz., the duodenum, the jejunum, and the ileum. It constitutes four-fifths of the whole intestines, the larger making up the other fifth. They are used to aid in assimilating the food after digestion, and convey forward the excrementiticus matter. ”

“ The retention of fluids, transuded serum, bile, intestinal juices, and partly-altered food is hurtful. Decomposition sets in and gas is developed, which by distending the bowel causes great suffering and increases the inflammation. The movements of the intestine are not entirely under control; the patient must be fed; digestion and assimilation involve the activity of inflamed parts. The stomach can be made to do most of the work, but the sympathy of action is so close between the stomach and intestines that one cannot function without the other being excited into activity. ”

“ Several condiments act upon the stomach, or on the intestine, after having first produced an agreeable sensation of taste. The excitation to which they give rise does not extend to the central organ, there to produce the same sensation. They are limited to the stomach and to the intestine, and serve to favor digestion and absorption. The gastric juice, we know, is not secreted continually, but only when there is something in the stomach. ”

“ The stomach, after a variable length of time, during which the peptic ferments accomplish their allotted task more or less thoroughly and completely, delivers the resultant mass over to the small intestine, where the secretions from the pancreas, liver, and intestinal glands, by finishing the transformation of the starch begun before the stomach was reached, emulsifying the fatty constituents, etc., complete the complex work of digestion. ”

“ As chemical factors, water and salts are the two necessary substances for gastric digestion, since the enzymes in the juices cannot act except in their presence.
Alkaline carbonates and fatty foods both check the flow of gastric juice, and retard digestion. The psychic factors which result in a stimulation of the secretory cells in the stomach are exerted through the sight, smell, and taste. One often hears the expression: “The food looked, smelled, or tasted so good that it made my mouth water.” ”

“ Adjuvants to Digestion.—In atony of the stomach the gastric mucous membrane responds feebly to the stimulus of food. There is failure in both muscular movement and gastric secretion, with slowness of digestion as a result. To meet this condition we seek to increase the digestive power by the addition of certain principles natural to the digestive process—viz. the mineral acids, pepsin, and pancreatin. Of these acids, the hydrochloric should be preferred, because it is the natural acid of the gastric juice. ”

“ And it is not at all strange that they should, since there is so much pressure from within, so much pressure downward, and so much pressure from without—all through the requirements of fashion, indulgence, and ignorance. But the stomach, upper portion of the duodenum, and small intestine, cæcum, the ascending colon, and especially the transverse colon and sigmoid flexure, are susceptible to various forms of displacement, inhibiting the ready flow or passage of food stuffs, gases, and feces from one segment of the digestive apparatus to another, until the vent is reached. ”

“ The food over and over again is brought into closest contact with the intestinal walls by the swift kneading movement of the muscles. Thereby not only is the undigested food intimately mixed with the digestive juices, but the digested food is thoroughly exposed to the organs of absorption. Mall has shown that contraction of the intestinal wall has the effect of pumping the blood from the submucous venous plexus into the radicles of the superior mesenteric vein, and thus materially aids the intestinal circulation. ”

“ DISEASES OF THE LIVER. Liver complaints are always closely related to other diseases of the digestive organs. The colon being clogged, the intestines are rendered sluggish, which in turn acts upon the duodenum, or second stomach, and prevents the food from properly passing out—then fermentation takes place. Bile is poured out on the accumulated food again and again, for the presence of anything in the duodenum is a demand for the secretion of bile. ”

“ After the small intestine is opened the enterotome is introduced through the ileocæcal opening and the large intestine cut in the anterior tænia as far as the rectum. The opening of the intestine within the body should be left until all the other abdominal organs have been examined, because of the disagreeable mess made by the escape of the intestinal contents into the cavity. ”