The Colon, starting as it does in the right iliac fossa, passes upward, anterior to the right kidney bending at the hepatic flexure rather sharply. From there it passes across the abdomen about the level of the umbilicus to the splenic flexure. Between these points, you remember, it is covered with and is attached to the omentum. From the splenic flexure where the colon is also normally angulated it passes downward in the left lateral gutter, not so far from the left kidney, to a point about the level of the iliac crest. There it is held rather firmly by a reflection of the parietal peritoneum. From that point to the anal ring, the colon is quite loosely bound and forms the normal “S” shaped or Sigmoid Colon. The Rectum of course, as implied by the name, is straight.
Histologically the colon consists of three main coasts, the mucous membrane, the muscular and the peritoneal.
When considering the mucous membrane we recognize the type of cell as columnar epithelium and also that the membrane is loose and contains innumerable secreting glands.
The muscular coat consists of longitudinal and circular involuntary muscle fibres controlled entirely by the autonomic nervous system.
The serous, or peritoneal coast, is really a cover and is the means of keeping the colon, as well as other viscera, out of the peritoneal cavity. It is between the two layers of the peritoneum that the blood supply arrives at the colon. It is also in this space that mesenteric glands exist as a part of the lymphatic system draining the gut. These glands are normally not to be seen by the naked eye and are detected only by means of the microscope.
In regard to colonic function the principal facts are the normal daily number of stools and the amount of time required to pass a meal from the mouth to the anus. It has been determined by hourly flouroscopic examination that a normal person, or that person who has no intestinal pathology or symptoms, defecates three times daily, the time of defecation being about one hour after each meal. It has also been determined that the time required to pass a barium meal from ingestion to defecation is about nine to thirty-three hours, depending on the number to stools a day and on the time of meals and defecation.
A safe, practical average may be assumed as nineteen to twenty- four hours. Any meal requiring over forty-eight hours to pass shows pathological stasis.
(It should also be noted that a normal defecation empties the colon from the splenic flexure downward).
At different parts of the intestine the barium meal arrives at a fairly definite average time after ingestion.
four hours after the meal enters the stomach it should be in the caecum and part of the ascending colon. Any barium remaining in the small intestine after six hours indicates an abnormal condition either in the terminal ileum or in the colon.
The hepatic flexure is reached between five and eight hours after the meal, the splenic flexure between seven and fourteen hours and the sigmoid between eight and sixteen hours.
The average, again, is as follows: Four hours to the caecum, six hours to the hepatic flexure, nine to the splenic flexure, eleven to the sigmoid and twelve to the rectum.
It will be noted, therefore that the meal spends most of the time in the colon and if this organ does not function properly various illnesses may result.
When patients with abdominal symptoms present themselves to you they should not be dismissed with a simple laxative or cathartic or even with advice about diet and exercise. It is most important to study the individual being and determine from all angles the condition of the colon.
By far the most important examination, next to a very complete history including habits of diet, exercise, employment, defecation, laxatives, etc., is a gastro-intestinal X-ray study. It is most difficult to arrive at an accurate knowledge of the patients colon without such a series of pictures or fluoroscopic examinations. The principal objection is the cost. Make-shift methods, as the feeding of charcoal and the examination of the feces for its appearance, is of practically no value and should not be relied upon.
If the X-ray shows stasis beyond the normal limits and if the patient does not defecate at regular normal intervals it is quite advisable to treat the colon even though symptoms may be vague and lead you elsewhere in search of trouble.
Briefly describing the abnormal colon, it can be said that the organ is, at times, much longer than normal and is often dilated and constricted at different portions. The constrictions or atresias are caused by bands of tissue known as pericolic adhesions. If not dense and constricting they may be recognized or understood as Jacksons membrane. No one had definitely shown the origin of these membranes but it may be assumed that they are either congenital or acquired through irritation of the peritoneal coat by infectious processes.
They extend usually from the lateral walls to the colon attaching themselves on the mesial surface of the gut. When existing simply as Jacksons membrane they have no harmful influence but when they contract like all scar tissue the gut is rolled over on its long axis and firmly fastened in the lateral gutters and in addition the gut is angulated or kinked.
As partial obstruction takes place there is dilatation above the constriction. As a result there is stasis with absorption of material that should have been excreted, the most harmful of which are the products of protein decomposition.
As pressure on the colon increases, the mucous membrane is destroyed and ulceration begins. Through these openings bacteria penetrate and enter the lymphatic stream as well as the toxins from food decomposition.
These bacteria are intercepted by the mesenteric lymph nodes which become quite large and hard, much the same as lymphatic glands do elsewhere in the presence of infection. Cultures of these glands show different types of colon bacilli and streptococci. In one case live typhoid organisms were found in the mesenteric glands long after the attack.
Finally these glands break down and either become calcified or form scar tissue in the mesentery which adds to the stasis.
A “Vicious circle” is formed. The colon is constricted, then it breaks down and becomes infected, toxins and bacteria enter the lymph spaces and to the peritoneum, mesenteric glands intercept infection, they are destroyed, scar tissue develops and the process starts all over again.
All this is of value to the general practitioner as he meets with such patients every day. colonic sepsis occurs in such a verity of diseases either as the causative or contributory fact, or in association with some other disease, that no attempt is made to name the illnesses. It is sufficient to know that therapy directed toward relief of colon pathology will benefit the patient so much that the treatment of other entities is enhanced to a great degree.
Pathology is only of value when it leads of therapy and in the case of the colon we can offer the patient much hope for relief and ultimate recovery.
After a diagnosis is made the procedure is to give the proper diet, prescribe suitable exercise and then treat the colon locally. In addition to this the patient must be instructed in the proper hygiene of the bowels.
Given a colon case, with X-rays completed and the diagnosis made, the patient should be placed on a meat-free diet. Eggs, cheese and other food rich in protein should be restricted to a minimum.
Carbohydrates should be relatively increased so that the food values should approach the percentages in human milk, namely, protein 1 per cent., fats 4 per cent. and carbohydrates 7 per cent. There is no particular reason for these percentages except that experience shows that people thrive better on such a diet.
The diet should also be bulky containing a large amount of non- absorbable material. This can be accomplished by the addition of various articles on the market made for that purpose. Bran, agar, psylla seeds and so on, are examples. These are not necessary if sufficient vegetables are eaten.
Simple sugar as Maltose, Dextrose and Lactose should be added to the diet. One of the most useful of such products is Lacto- Dextrin and is quite valuable in changing the contents of the feces.
A simple but useful adjunct to diet, and yet one of the hardest things to impress upon the patient is the use of water. The chronic intestinal invalid simply will not drink enough fluid and when properly instructed replies, “I cannot take water, it makes me sick.” Nevertheless, you must insist that your patients drink at least two to four glasses of water in succession after arising and at least two glasses about one-half hour before the mid-day and evening meals., If this procedure is rigidly followed most of the intestinal stasis will disappear.
Physical exercise is most important for the sedentary patient and for this purpose you can use the gymnasium, phonograph records or best of all the radio which brings to you the proper exercises each morning.
