Large intestine

The large intestine belongs to final department of a digestive tract. 

This body is placed in an abdominal cavity and in a small pelvis.

Anatomists divide a large intestine into several departments: a caecum with an appendix, colonic (ascending, cross, descending, sigmoid) and a rectum.

Average diameter of a large intestine fluctuates from four to ten centimeters. Length of a large intestine makes one-two meters.

The caecum is located in the field of transition of an ileal gut to a large intestine. Length of body – 6-8 cm, average diameter – 7 cm.

The caecum passes into the ascending colon with two bends – right (hepatic) and left (splenic). Between bends in an abdominal cavity it passes into a cross colon which length averages 40-50 cm. Its situation depends on age, and also on constitution type. In the left part of an abdominal cavity the cross gut passes into the descending gut.

The descending gut, reaching the left ileal pole, passes into a sigmoid colon which length varies from 16 to 67 cm. This gut has an appearance of two loops which size and a form are subject to essential individual variations. The sigmoid gut is placed intraperitoneally and from all directions is covered with a peritoneum. The gut is attached by a mesentery to a back abdominal wall that provides its mobility.

Rectum – final department of a large intestine. Its narrowest part passing through area of a crotch is called the proctal (anal) channel. The proctal channel comes to an end with an opening - an anus (anus).

In an anatomic structure of a wall of a gut allocate four layers - a mucous membrane, a submucosal layer, a muscular layer and a serous cover.

Inside layer of a large intestine is the mucous membrane. Throughout a gut it is covered with a cylindrical epithelium, and near the proctal canal – a cylindrical and squamous (flat) epithelium. In some sites (around anorectal transition) the proctal channel is covered by anodermy – the epithelial vystilka of special type which is not containing sebaceous glands and hair follicles.

The mucous membrane forms numerous folds. In ampullar department they cross, in proctal department – longitudinal. Distinguish three constant folds of cross type - upper, lower and average. The submucosal layer is presented by the connecting fabric containing lymphatic and blood vessels. The muscular layer consists of outside longitudinal and internal circular muscles.

Functions of a large intestine

Let's list the main functions of a large intestine:

• Digestive function of a large intestine consists in final processing of the remains of food enzymes (release of water and residual nutrients). In a caecum process of consolidation of liquid contents of intestines begins;
• Soaking up – water and nutrients spread from the blind person ascending and the descending departments of a large intestine of all bodies via circulatory and lymphatic channels;
• Muscular (motor) – a large intestine strengthens or reduces the frequency of reductions of muscles, thereby providing continuous advance of a chyme on the digestive channel.

Besides, the large intestine through an anus removes substances, toxic and useless for an organism.

Inflammation of a large intestine

Inflammation of a large intestine (colitis) – the most widespread disease of digestive tract.

Rough errors in food, various infections, hit in an organism of household and industrial poisons can be the reasons of an inflammation of a large intestine. In certain cases the inflammation arises repeatedly as the independent disease having the immune nature or as a result of the disturbances which happened in a small bowel or a stomach.

Now allocate a chronic, acute, ulcer and spastic inflammation. Symptoms of display of a disease is emergence of slime and impurity of blood in fecal masses, breakdown, slackness, temperature increase, the increased gas generation, diarrhea, appetite loss.

Ulcer colitis - an inflammation mucous a large intestine, followed by formation of ulcers. At this form of an inflammation most often the periods of an aggravation are replaced by the remission periods. The first symptom of ulcer colitis - a colicy pain in the lower area of a stomach.

At a spastic colitis the fecal mass of the patient in a form reminds dense lumps.

Polyps of a large intestine call outgrowths of a mucous intestinal wall. Similar growth of mucous can have the form of a sphere, a mushroom, a semicircle (without leg or on a leg).

Polyps of a large intestine represent high-quality new growths most of which often regenerate in cancer (through five – ten years after their education). Growth of polyps considerably slows down motility of intestines that can result in its impassability.

Most often formation of polyps happens asymptomatically, but sometimes growth of mucous is followed by pain, emergence of slime and blood in fecal masses. Kolonoskopiya - the main diagnostic method of polyps.

Large intestine – treatment

Treatment of a large intestine consists in purpose of a special diet and medicines (antiseptic agents, analgetics, spasmolysants, laxatives, calmatives, vitamins, bacterial drugs), medical enemas. A medical enema – one of the most effective methods of treatment of a large intestine.

All types of polyps of a large intestine are removed in the surgical way. For cauterization of polyps in medicine use an electrothermic coagulation method.