Rectal feeding is an artificial method of giving food to a patient. It is adopted in cases of acute gastric catarrh, ulcer of the stomach and duodenum, in states of unconsciousness, such as apoplexy, coma, and whenever it is undesirable or impossible to give food by the mouth.

Each meal should consist of not more than five or six fluid ounces. It may be given through a special apparatus, but the less complicated it is the better. Any doctor or chemist can make a simple apparatus that will answer quite well. Take a large rubber catheter (No. 12), join it by means of a bit of glass tube to 2 1/2 or 3 feet of rubber tube of the same calibre, and put a glass funnel into the opposite end. The patient may lie on the back or side, or in the knee-elbow position. The catheter must be carefully insinuated into the bowel, the idea being to get it through the rectum and into the sigmoid flexure of the colon if possible. This is not always easy to do; the catheter may catch against one of the folds of mucous membrane in the rectum, called Houston's valves, and become doubled up. Having got it into position, the funnel should be held 2 or 2 1/2 feet above the hips, the food poured in and allowed to get into the colon by its own weight. It is often a slow business; but the nurse must be willing to spend a little time over it. If the food were injected into the bowels it would probably be returned almost immediately. By allowing it to find its way in by gravity the bowel is not likely to be irritated by its presence, and it will probably be retained. That is the usual mode of intermittent rectal feeding. It is possible, however, to provide continuous rectal feeding, which requires less attention and is less tiring to the nurse, by fixing the funnel to a stand at the bedside, and applying a clip to the rubber tube to regulate the flow. This can be so regulated that five or six ounces would occupy about two hours in getting into the bowel; and it is probable that the food would be better retained and more nutriment be got out of it than by intermittent feeding.

The rectal mucous membrane becomes very irritable from the frequent passage of the catheter; indeed, it is very tender from the first in some persons. To reduce this irritability it is advisable to add five drops of laudanum to each alternate feed, and also a few grains of common salt and bicarbonate of soda. It is also necessary to wash out the rectum once a day with a boracic lotion or some other mild antiseptic to soothe the irritation and check putrefaction. Furthermore, it is usual to inject into the bowel about a pint of water once or twice a day to reduce thirst.

It is not uncommon for mumps to occur during a course of rectal feeding. The reason for this is not quite clear, but it probably has nothing to do with the rectum at all. The mouth normally contains a lot of bacteria, and when the body is diseased the gums become very sore, and a chronic suppurative process may occur (pyorrhoea alveolaris). When mastication is going on, the number of bacteria in the mouth is kept down by various things - e.g. by mastication and drinking. But when no food or drink is taken by the mouth the bacteria flourish abundantly, infect the salivary gland, setting up mumps (parotiditis), and sometimes ending in suppuration. These symptoms may be prevented by the frequent use of a mouth-wash. If swelling occurs the treatment required will be that for ordinary mumps.

There are various recipes for rectal feeds. The basis of most of them is either plain or peptonized milk; but eggs, beef-tea, meat extracts, peptones, glucose, malt extract, and ordinary sugar are also used. The following are useful examples: -

1. A raw egg well beaten, a cupful of warm milk (plain or peptonized), and a saltspoonful of salt. The addition of salt assists in the digestion and absorption of eggs, milk, etc.

2. A pint of milk, three raw eggs, a tablespoonful of extract of malt, and a tablespoonful of brandy. It will make four feeds. The extract of malt should be put into the warm milk and egg about ten minutes before the addition of the brandy.

3. One ounce of Carnrick's liquid peptonoids or Kem-merich's peptones, the yolk of one egg, 1/4 pint of milk, 5 drops of laudanum, half a saltspoonful of salt and bicarbonate of soda.

4. A cupful of pancreatized milk, two egg-yolks, a dessertspoonful of glucose syrup, and a little salt.

5. Cod-liver oil, 2 ounces; one egg-yolk; lime-water, 2 ounces.

6. Finely minced meat (beef, mutton, or fowl) 5 ounces, a cupful of milk, and a tube of Fairchild's peptonizing powder; after the material is peptonized, add 2 tablespoons-ful of glucose syrup and the same amount of brandy. It will make two or three feeds.

7. A pint of milk and the white of four eggs is pancreatized by means of a tube of powder or some liquid pancreatic extract; it is then boiled to destroy the ferment and sterilize it, and two or three tablespoonsful of glucose and some salt added to it. It will make four feeds.

8. Beef-broth or beef-tea 1/2 pint, two raw beaten eggs, a wineglassful of white wine, and a saltspoonful of salt.

There is no doubt about the usefulness of this mode of feeding. It will help to carry the patient through a bad time, provided the time is short, say a week or ten days. But we must not be deluded by it, however much we wish to impress our patients with its value and importance. We know very little about digestion in the colon. Until recently it had been denied that digestion occurs in this part of the bowel. But we know that the pancreatic enzymes reach the colon, and trypsin, one of the most powerful digestive enzymes, is to be found in the faeces. But the pancreatic enzymes act best in an alkaline medium, whereas the contents of the colon are slightly acid; therefore there is not much chance of rapid digestion going on there. On the other hand, we cannot deny that any digestion occurs in this part of the economy. Constipated persons not only retain their food in the colon a very long time, but they extract nutriment from it; indeed, very little more than debris remains in their faeces. There is therefore some hope that food introduced through the rectum will be partly digested and absorbed. Nevertheless, it must be clearly understood that food introduced through a catheter or rectal tube does not get very far into the colon. If it can be got beyond the sigmoid flexure (corresponding externally to the level of the umbilicus or top of the left hip), some good may be done and some digestion take place; but if the food only gets into the rectum no digestion will occur. What, then, is the good of it? Well, some of the liquid, and especially peptonized, food will be absorbed. Not a lot, perhaps; certainly not more than a fourth part of the nutriment required by a person absolutely at rest. Moreover, there is a limit even to the capacity for absorbing liquids. It will be observed that, in spite of the most careful rectal feeding, the patient continues to waste away, and is in a condition of semi-starvation. An examination of the urine shows that more nitrogen is excreted than the patient absorbs ; the amount of carbonic acid from the lungs is greater than can be accounted for by the oxidation of the food - both the nitrogen in the urine and carbonic acid from the lungs are derived from the burning of muscle and fat for fuel. Whence it has been said rectal feeding satisfies the mind rather than the body. If we can satisfy the mind we shall do something for the patient's comfort. If we can prevent the sensation of hunger and thirst, we shall do a good deal. Moreover, a gastric case will be free from pain when no food is put into the stomach. But science has proved that when raw milk and egg are given 21 per cent is usually absorbed; when peptonized milk and egg are given, from 30 to 40 per cent is absorbed; when peptones are given, 50 to 70 per cent will be absorbed. Very little fat is absorbed; the figures vary extremely and show an absorption of 2 to 33 per cent, and probably not more than one ounce of cod-liver oil, liquefied butter or milk fat would be absorbed in a day. On the other hand, various kinds of sugar are taken up readily. When one or two ounces of glucose were used daily in a 10 per cent solution, from 75 to 90 per cent disappeared. It is not certain that all the sugar which disappears from the lower bowel is absorbed; some of it may be fermented. But until this fact is proved, the free use of grape sugar (glucose) or malt sugar (extract of malt) is strongly recommended as a part of all rectal feeds.