This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
These symptoms are not necessarily present after the first day or two of rectal feeding. In an obstinate case of gastric haemorrhage in which absolutely nothing - not even water - was given by the mouth for more than a week, I questioned the patient in regard to her sensations of hunger and thirst, and she told me that they were entirely relieved after the first twenty-four hours' use of nutrient enemata. The mouth and tongue were not dry, and she did not lose weight during this period. I have been told the same thing by other patients.
An interesting case was reported by C. W. Brown, of Washington, in which a patient suffering from carcinoma with ulceration of the pyloric end of the stomach was supported for forty-three days upon exclusive rectal nourishment consisting of from four to six ounces of beef tea and milk, which were given on an average once in three hours, with the occasional addition of laudanum and a little whisky. During an interval of improvement which followed the exclusive use of injections, the patient was able to take some food by the stomach, though not enough to satisfy the craving of hunger and prevent a feeling of faintness; but these symptoms were overcome by giving four nutrient injections daily in addition to the milk taken by the stomach.
The common practice of giving nutrient enemata by a Davidson syringe with a short hard-rubber or steel nozzle is always to be condemned. In the hands of an unskilful nurse, irritation and sometimes haemorrhages are likely to be produced in this way, sooner or later.
In commencing the use of rectal alimentation, especially in cases which manifest much irritation of the lower bowel, it is important to employ a long, soft, flexible rubber catheter or rectal tube which can be passed well up, for eight inches or more, to the sigmoid flexure. In selecting the tube, one should be chosen which is not so flexible that it is liable to bend or double upon itself, but which is not so stiff as to give pain or damage the mucous membrane if it happens to catch in a fold of its surface. For children a No. 12 or No. 14 ordinary "velvet-eyed" flexible catheter may be used, and passed up as high as the sigmoid flexure. For adults the tube should be of moderate calibre, not exceeding the diameter of a stout pen handle. The tube or catheter should be dipped in sweet oil, melted butter, or vaseline; but glycerin must not be used, for it excites peristalsis.
In adults the tube should be passed in for from ten to twelve inches, for the injection should be placed as high up as possible. When this is done there is less liability to its rejection, and it is brought in contact with an extensive mucous surface. There is a further physiological or anatomical reason for placing the injection as high up as may be, in the fact that the sigmoid veins and those returning the blood from the upper rectum communicate with the inferior mesenteric vein, while those from the lower third of the rectum communicate with the inferior vena cava. Consequently, whatever is absorbed by the wall of the inferior third of the rectum passes into the inferior vena cava without going to the liver, but that which is absorbed higher up is returned to veins whose contents reach the liver directly through branches of the vena porta. It is in the liver that the further assimilation of protein takes place in great part, and hence the desirability of observing this rule.
It was found by Brown, in the case above cited (p. 410), that the patient was able to discriminate between the taste of iodide of potassium and ergot, etc., in from a quarter to half an hour after these medicines had been given per rectum. The same phenomenon has been noticed from the injection of such substances directly into the stomach through a gastric fistula, and it is due to their ready absorption and conveyance in the blood to the taste bulbs in the tongue or to the saliva, in which fluid the iodide of potassium is promptly excreted.
According to some observers, under the best conditions not over one fourth of the necessary nutriment can be absorbed from the rectum (Bauer). Such a statement should be considerably modified, for, as a matter of practical experience, many patients may be kept alive and gain slightly in weight upon the use of nutrient enemata, when they are intelligently given. If injected but a short distance into the intestine, the absorbing surface is so limited that comparatively little material is taken up; but if given in the manner prescribed above, through a long catheter inserted high up, much more will be retained, and the benefit derived from such injections will be enhanced.
The injection should be applied by means of a small hard-rubber syringe, which need not hold over two ounces. Very little force should be used, and the patient must be told not to strain. After the syringe is filled, by holding it vertically nozzle uppermost and pressing it until the fluid exudes from the nozzle, all air is excluded. When a Davidson syringe is used for the purpose of injecting small quantities of fluid, it very often happens that air is drawn into the syringe in addition to the materials of the enema, which, when injected, is very apt to excite peristalsis and evacuate the bowel. The use in unskilful hands of a funnel or fountain syringe for filling the tube is open to the same objection - that air is likely to enter the rectum. In any case it is well to fill the tube with the injection fluid before it is inserted.