The Rectum

Theory and Equipment. Many diseases of the human body can be identified by visual appearance. Tumors in the upper gastrointestinal (GI) tract, for example, possess a characteristic salmon pink color (3). The presence of such a color can be an indication of disease. Endoscopy is the medical imaging tool used to detect such colors in the inside of hoUow internal organs such as the rectum, urethra, urinary bladder, stomach, colon, etc. An endoscope is the instmment used to perform endoscopy. Endoscopic imaging involves the production of a tme color picture of the inside of the human body using lenses and either hoUow pipes, a fiber optic bundle, or a smaU CCD camera. AU three use a large field-of-view, sometimes referred to as a fish eye, lens to aUow a 180° field of view. 

Rectum. Local treatment of conditions and diseases of the rectum, including hemorrhoids and local inflammation, usually involves dmg-containing suppositories or enemas. 

Solids (eg, suppositories), liquids, or foams inserted into the rectum... 

Suppositories insert 1 high in the rectum and retain 15 min rectal liquid insert all the liquid into rectum toward the navel 10-60 mL7d PO... 

Mesalamine—Swallow tablets whole do not chew them. For the suppository, remove foil wrapper and immediately insert tiie pointed end into the rectum without using force. For tiie suspension form, instructions are included with the product. Shake well, remove the protective sheath from the applicator tip, and gently insert the tip into the rectum. Partially intact tablets may be found in the stool if this occurs, notify the primary health care provider. 

Corticosteroid intrarectal foam, hydrocortisone acetate intrarectal foam Cortifoam Adjunctive therapy in treatment of ulcerative proctitis of the distal portion of the rectum Local pain or burning, rectal bleeding, apparent exacerbations or sensitivity reactions 1 applicatorful once or twice daily for 2 wk and every second day thereafter... 

The inflammatory process within the GI tract is limited to the colon and rectum in patients with UC (Fig. 16-1). Most patients with UC have involvement of the rectum (proctitis) or both the... 

Flexible sigmoidoscopy can be performed to identify obstruction in the rectum and lower colon, whereas colonoscopy can evaluate the entire colon for organic disease. 

Adjuvant therapy consisting of 5-fluorouracil-based chemotherapy in combination with radiation therapy should be offered to patients with stage II or III cancer of the rectum. 

Colon cancer A disease in which cells in the lining of the colon become malignant and proliferate without control. Often referred to as colorectal cancer to include cells of the rectum. 

Colonoscopy Visual examination of the colon using a lighted, lens-equipped, flexible tube (colonoscope) inserted into the rectum. 

Digital rectal examination Procedure in which the health care professional inserts a gloved finger into the rectum to examine the rectum and the prostate gland for signs of cancer. 

Proctitis Inflammation confined to the rectum in patients with inflammatory bowel disease. 

Rectal prolapse Sinking of the rectum through the anal sphincter so that it is visible externally. 

Intestinal surface area and total blood flow to the GIT are smaller than in adults and may influence the efficiency of absorption. With regard to the use of rectal suppositories, one must keep in mind that the completeness of absorption will be a function of retention time in the rectum. Since bowel movements in... 

A second form of motility in the large intestine is mass movement. Three or four times per day, typically after a meal, a strong propulsive contraction occurs that moves a substantial bolus of chyme forward toward the distal portion of the colon. Mass movements may result in the sudden distension of the rectum that elicits the defecation reflex. 

This agent is usually administered as a 3-g suppository and exerts its effect by osmotic action in the rectum. As with most agents given as suppositories, the onset of action is usually less than 30 minutes. 

There are two forms of idiopathic inflammatory bowel disease (IBD) ulcerative colitis, a mucosal inflammatory condition confined to the rectum and colon, and Crohn s disease, a transmural inflammation of GI mucosa that may occur in any part of the GI tract. The etiologies of both conditions are unknown, but they may have a common pathogenetic mechanism. 

There are a wide range of ulcerative colitis presentations. Symptoms may range from mild abdominal cramping with frequent small-volume bowel movements to profuse diarrhea (Table 26-3). Many patients have disease confined to the rectum (proctitis). 

When the patient has lost significant amounts of blood (through the rectum), blood replacement is also necessary. 

There are two different mechanisms behind ordinary causes of constipation, functional and outlet obstructions. Functional constipation is caused by the slower movement of the colon, peristalsis, which comes with old age, often in combination with less physical activity and less intake of fibre containing food. Outlet obstruction is a result of incapacity to empty the rectum from faeces often due to too large masses of stool blocking the anus. It can also be caused by anal stricture from haemorrhoids or scar tissue caused by fissures. 

Temperature Recording. Use an accurate temperature-sensing device, such as a clinical thermometer or thermistor or similar probe, that has been calibrated to ensure an accuracy of 0.1° and has been tested to determine that a maximum reading is reached in less than 5 min. Insert the temperature-sensing probe into the rectum of the test rabbit to a depth of not less than 7.5 cm and, after a period of time not less than that previously determined as sufficient, record the rabbit s temperature. 

Alimentary canal sympathetic dilates, parasympathetic constricts, especially the rectum (see effect of D.F.P. in treatment of post-operative paralytic ileus, p. 196). Furthermore, parasympathetic stimulates glandular secretion. 

By means of this reduction process it is possible to obtain, from the corresponding aldehydes, alcohols such as trichloroethyl alcohol or cinnamyl alcohol, which are not otherwise readily accessible or are otherwise inaccessible. Tnbromoethyl alcohol ( avertin ), an important narcotic, is prepared in this way (F. F. Nord). It is given by the rectum. 

HIV is present in peripheral blood mononuclear cells, the major source of transmitted virus. Titers, however, are quite low, about 10,000 infectious doses per ml of blood, so that the blood is less infectious than in hepatitis B virus infections. The amount present tends to fall after seroconversion and rises again during development of AIDS-related complex and AIDS. Smaller amounts of virus are also present in semen and saliva, and probably even smaller amounts in colostrum, the human cervix, and tears. Infection is reported in CD4 positive submucosal cells in the rectum and large bowel and could be a route of entry in homosexuals. 

Colon The long, coiled, tubelike organ that removes water from digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus. [NIH]... 

Ecstasy most commonly comes in the form of a small pill (Figure 3.2). These pills come in a large variety of shapes and colors with various designs imprinted on them. A typical Ecstasy pill costs between 10 and 25 and contains 75-150 milligrams of MDMA. Since these pills look so much like candy, they are often concealed by mixing them into a bag of M Ms or Skittles , or even placing the pills inside a Pez dispenser. The pills are usually chewed or taken with a drink. In rarer instances, the pills are crushed into a powder and snorted or injected intravenously, or the pills are inserted into the rectum ( shafting ). 

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