SECTION III.

PATHOLOGY OF DYSPEPSIA.

WHEN the digestive organs are in a healthy state, it appears that a mass of food, composed of a variety of articles, is changed, in the course of from three to five hours, into a homogeneous pultaceous matter called the chyme. The observations of Majendie have rendered it probable, that, sometime after the process of digestion has commenced, a motion begins to take place in the stomach, by which the contents are slowly moved backwards and forwards betwixt its splenic and pyloric portions. This motion is said to be more active, and to extend over a greater portion of the stomach, when it contains but a small quantity of food; and to be more limited when the quantity is large, being then in a great measure confined to a portion near the pylorus. After this alternate motion has continued for a certain time, the chyme is at last gradually propelled into the duodenum, and thence very gradually through the intestinal canal, by a certain consecutive muscular action, which is called its vermicular or peristaltic motion. In this course, the alimentary matter is mixed with the bile, pancreatic juice, and the fluids of the intestinal canal; and it undergoes farther important changes, by which it is converted into chyle fit for absorption, and the excrementitious matters are separated and expelled. The fluid called the gastric juice appears to be merely a mixture of the mucous and follicular fluids of the stomach.

It is evident

that it bears an important part in digestion, but not as a mere chemical solvent, for it is not ticles of food out of the stomach.

found to dissolve ar

All that we know

therefore of digestion is, that it is the result of the combined action of this fluid, and of the peculiar muscular motion of the stomach now referred to. In healthy digestion, it appears that no gas is generated in the stomach, but that a certain quantity is evolved in the farther progress of the alimentary matters through the intestines, especially in the colon; and it is said to be composed of carbonic acid, hydrogen, and azot, in various proportions.

When these actions are in any respect deranged or deficient, the alimentary matters are not converted in the regular manner into healthy chyme; but, remaining perhaps longer in the stomach than, in the healthy state of the process, they would do, they undergo in a greater or less degree those chemical changes, which would happen to them in other circumstances. Hence the generation of acidity, the evolution of gases of various kinds, and the lodgment in the stomach of matters imperfectly digested, partly fermented, perhaps partly putrid; hence, also, irregular muscular contractions, arising from the morbid stimuli thus produced, giving rise to regurgitations of matter into the œsophagus, eructations, and perhaps vomiting; or, the muscular coat yielding to the distending force of the evolved gaseous fluids, there are produced painful distention, oppression, and anxiety, or in other words, a paroxysm of dyspepsia.

For the healthy condition of the process of digestion, in all its stages, the following circumstances appear to be necessary:

1. A healthy state of the muscular action of the stomach.

2. A healthy, consecutive, and harmonious action of the muscular coat of the intestinal canal.

3. A healthy state of the fluids of the stomach, both as to quality and quantity.

4. A healthy state as to quality and quantity of the other fluids, derived from the liver, pancreas, and intestinal membrane.

5. A healthy state of the mucous membrane itself, both in the stomach and intestines.

The dependence of the function of digestion upon the influence of the eighth pair of nerves, is among the most beautiful discoveries of modern physiology; but nothing of a practical nature has hitherto been deduced from it.

In the preceding part of this treatise, we have seen these functions deranged by various diseases of the coats of the stomach; but our attention, under the present section, is chiefly directed to those cases in which the derangement is of a functional nature, or not connected with any change of structure either of the stomach itself, or of any of the neighbouring parts. Upon the strict principles of pathology, it is extremely difficult to ascertain the exact nature of these functional derangements, as they are merely impaired actions of living parts; but I think there are a few points which we may consider as not entirely conjectural.

1. We have much reason to believe, that the muscular action of the stomach may be deficient, so that the alimentary matters remain in it too long, are imperfectly changed, and pass into chemical decompositions. We know the state of the urinary bladder, in which its muscular action is lost or very much impaired, and in consequence of which it is gradually distended, so as to hold an enormous quantity of fluid; and when emptied by the catheter, it does not contract equally, as in the healthy state, but falls flat like an empty bag. A state analogous to this we not unfrequently see in the stomach on dissection, a state in

which it appears much enlarged, and collapsed by flattening, without healthy contraction.

2. There may be a deficiency of the corresponding and harmonious intestinal action, interfering with the second stage of digestion, and giving rise to imperfect chylification and various morbid actions in the upper intestines.

3. The various fluids may be deficient in quantity, or morbid in quality, so as to derange the process in various ways. We have grounds for assuming that the fluids of the stomach may be in a morbid condition, without actual disease of its coats. We see in certain cases a fluid brought up by eructation in large quantities, in a morbidly tenacious state, quite different from the healthy appearance of the fluids of the stomach; and we have reason to believe, that similar changes may take place in the other fluids concerned in digestion, particularly the bile.

4. If the mucous membrane be morbidly irritable, the muscular coat will probably be too easily excited to action, and a different state of things will arise. If this occur in the stomach, the articles will not be allowed to remain in it a sufficient time for healthy digestion; but, after producing much uneasiness, they will either be rejected by vomiting, or propelled in a half-digested state into the intestine, there to prove a source of new irritation. This is probably the state to be afterwards more particularly referred to, in which animal food produces much uneasiness in the stomach, often followed by vomiting; but in which digestion goes on in a healthy manner, on a regimen restricted to farinaceous articles and milk. If the irritability occur in the intestine, the articles may undergo their proper change in the stomach, but will be propelled too rapidly through the intestinal canal, without time being afforded for the complete process of healthy chylification; and, accordingly, in many affections of the stomach and bowels,

we see articles, even of the most digestible kind, pass through partially digested, or sometimes entirely unchanged.

I have no intention of entering at any length upon the treatment of indigestion; but there are a few obvious and important rules, which, upon the strict grounds of pathology, may be deduced from the points which have been briefly referred to.

I. It appears that the muscular action of the stomach is both more vigorous and more extensive when its contents are in small quantity, than when it is much distended; and, if we suppose the fluids of the stomach to be secreted in nearly a uniform quantity, their action must also be greatly regulated by the quantity of matter which they have to act upon; hence, the indispensable importance in dyspeptic cases of restricting the food to such a quantity as the stomach shall be found capable of digesting in a healthy manner. This is unquestionably the first and great principle in the treatment of indigestion; and without invariable attention to it, no other means will be of the smallest avail.

II. It appears that various articles of food are of various degrees of solubility in the stomach. When, therefore, digestion is apt to be easily impaired, it will be of the greatest importance, not only to avoid articles which are of difficult solution, but also to avoid mixing various articles which are of different degrees of solubility. Attention to this rule will probably favour in a great measure the process of chymification going on in a regular and healthy manner, by avoiding a state in which the solution of one article may be more advanced than that of another. The articles of most easy solution appear to be solid animal food, and white fish, both plainly dressed; vegetables are