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Colostomy is the operation of opening into the colon, or lower portion of the intestine. This procedure is one of the most important in abdominal surgery. It is sometimes necessary as a life- saving measure. It may be temporary or permanent as an artificial anus in the radical treatment of rectal cancer. Because of its appearance, its inconvenience and the very thought of an artificial opening in the abdominal wall a great deal of care is necessary to allay the anxieties of patients and their relatives when colostomy is necessary.
In some cases of acute intestinal obstruction the surgeon explores the abdomen and finds perhaps a large mass in the region of the pelvic colon or rectum that cannot be removed. An emergency colostomy is then performed in the transverse colon with the immediate purpose of saving life and with the further objective of providing temporary drainage should the growth be removable at a later date. In some such cases, when at first sight the primary cause of the obstruction seems beyond any possibility of surgical removal, after several weeks of colostomy drainage the infection subsides and the affected portion of bowel may then be removed. Colostomy may be necessary as a preliminary to other operations involving removal of the large bowel. Such an occasion arises if diverticulitis has produced vesico-colic fistula (between the colon and bladder). In some cases of severe incontinence due to abnormality or injury to the anus, a left iliac colostomy enables the patient to be free of the terrible inconvenience of perpetual soiling in the perineum. Injuries or abnormalities of the spinal cord produce paralysis of the anal sphincter mechanism and sometimes colostomy is essential. Congenital absence of the rectum or anus requires an emergency colostomy within a day or so of birth.
There are two main forms of colostomy. First is the loop colostomy which has two limbs. The opening is at the apex of the loop and the bowel has not been divided completely across. A variation of the loop colostomy is the double- barrel form in which the two limbs of the loop are separated by a piece of skinrafter complete division. This is also described as a defunctioning colostomy as it prevents the spill of faeces from the proximal to the distal loop. A second variety is the spur colostomy where a spur is formed by suturing the two ends together for several centimeters inside the abdomen. This is of particular value if the colostomy is temporary as the spur can be destroyed by a crushing clamp without risk of peritonitis or perforation since the limbs have become sealed together. When the spur breaks down, the artificial opening on the surface shrinks and sinks back below the skin level. The aim is that this should close spontaneously without further operation. The third type is the terminal colostomy in which the distal portion of bowel is removed completely or in the case of excision of rectum the lower end is closed to form a blind end. In grave emergencies the simplest form of colostomy is performed in which a loop of colon is brought out through the abdominal wall, where it is held by the insertion of a glass rod passed through a small hole in the mesentery. The ends of the glass rod are connected by a loop of rubber tubing which forms a 'bucket handle' . The abdominal wall is closed around the protrusion of the colostomy. Exteriorisation is another way of performing a colostomy. If a growth is present in a part of the bowel which can be brought readily through the abdominal wall (e.g. transverse or pelvic colon) the affected loop containing the growth is left outside and the peritoneum, muscles and skin are closed around the base of the loop where the two limbs converge. The loop of colon containing the growth is then removed, leaving two open ends of
el which can later be joined by crushing the spur between them. This operation avoids the handling of growth or unprepared bowel while the peritoneal cavity is open and so diminishes the risk of peritonitis. A formal operation for closure is required if a spur has not been made.
At the end of the operation a small incision is usually made in the apex of the loop to allow the immediate discharge of gas and faecal material which is collected as cleanly as possible before the patient leaves the theatre. A dressing of petroleum jelly gauze or tulle gras is applied on the exposed bowel. The skin incision may be sealed with Whitehead's varnish and a pad of cellulose tissue and wool is bandaged lightly over the opening. For fear of contaminating the abdominal wound before the peritoneal cavity has become sealed, the former practice was to leave the colostomy unopened for 48 hours. The initial opening may be enlarged by the surgeon two or three days after the colostomy has been raised. The bowel is usually divided (without anaesthetic) by an electric cautery which seals the blood vessels and prevents bleeding from the very vascular mucous membrane and muscle wall of the bowel. A method of draining the colostomy is by the use of Paul's tube. This is an angled wide glass tube which is inserted through a hole in the colostomy loop. It is tied in position in the same way as the caecostomy catheter and connected to a bedside jar with wide, thin, latex tubing.
 Research Colostomy
There are several methods of controlling bleeding during surgical operations. 1. When an incision is made, much of the bleeding comes from the skin edges and from subcutaneous tissue: small towels are often used, clipped to the edges of the wound to protect the cut surface, and prevent the repeated rubbing away of clot which would otherwise occur. These are called variously 'side-towels','skin towels' or 'tetra towels'. The latter term arose as these towels are commonly attached with four- pronged forceps ('tetra forceps'). 2. By pressure. As the surgeon makes his incision, he or his assistant applies a gauze swab to the raw area. Capillary and most venous bleeding stops almost immediately, and does not re-start unless the surface is rubbed. 3. Pressure forceps (artery forceps) are applied to the cut ends of arteries, as little of the surrounding tissue as possible being included in the jaws of the forceps.
These bleeding points are dealt with at some later stage in the operation in one of four ways. (i) The artery forceps are simply removed. Bleeding does not recur as the crushed end of the vessel has sealed itself off. (ii) Surgical diathermy current is applied to the pressure forceps, thus coagulating the end of the blood vessel. (iii) A surgical ligature is tied round the tissue included in the forceps which are then removed. (iv) A stitch is inserted and tied round the tissue held in the forceps in order to secure more firmly the end of the cut vessel. 4. The surgical diathermy is used to make the incision through the muscle and deep tissue layers. This technique is used especially in the treatment of cancer and particularly in the removal of vascular structures such as the breast. Small blood vessels are thus sealed as the tissue is divided. 5. The application of gauze soaked in adrenaline solution. This drug constricts the ends of the vessels and is particularly useful in the nose.
Where extensive bleeding may be expected - such as in plastic operations on the face - the operation area is sometimes infiltrated with a saline solution of adrenaline. By the time the effect of the adrenaline has passed off, the divided vessels have become blocked by clots. 6. The application of hot packs. The combination of pressure and heat speeds the clotting process and the retraction of the cut ends of vessels. 7. Thromboplastin released by enzymes from damaged tissue is essential to start the clotting process. There is very little damage in a clean surgical incision and thromboplastin formation can be brought about by the surgeon taking a small piece of muscle, and pulping it by repeated crushing with pressure forceps. This ' muscle graft' is applied to the bleeding area. Purified thrombin is supplied in powder in sterile ampoules ready to mix with sterile water: the solution is then applied with a swab or a spray and is particularly useful under skin grafts where it acts as a kind of glue. Fibrin foam is another preparation used extensively in neurosurgery where even a small amount of bleeding into the brain or nerve, may do irreparable damage. Gelatin 'sponge' supplied in small biscuit-like strips, can be used in bleeding cavities or tied to the surface of a bleeding organ. The sponge acts as an artificial network in which clotting occurs and the substance is itself absorbed.
Oxycel (oxidised cellulose) acts in a similar way and promotes rapid clotting. It is used in such sites as the prostatic cavity and can be tied around the catheter which is left in place at the end of operation. Calcium alginate is a similar preparation and is manufactured from sea-weed. The raw oozing surface is moistened with one solution which is then activated by spraying with a second solution containing calcium. All these artificial coagulants are only of use for 'low pressure' bleeding - that is from capillaries or small veins.
Research Surgical Haemostasis
Centrifugal machines are machines in which centrifugal force produced by rapid revolution is utilized. They may be used for drying articles, clothes, for instance, the articles being placed in the inside of a hollow cylinder made of wire-gauze or having many perforations in its walls, the moisture being driven off when the cylinder is made to revolve rapidly. Sugar is often separated from molasses by a centrifugal machine, the impure sugar being placed in a cylinder which is contained within a larger cylinder, the latter receiving the molasses which is removed by the rapid revolution of the inside cylinder. Cream is now commonly separated from milk in large dairies by this method, which can also be employed in the clarification of liquids, such as beer.
Research Centrifugal Machines
The Faraday cage is an earthed metallic wire or gauze screen enclosing electrical equipment to shield it from the influence of external electric fields. The principle, put forward by Michael Faraday, is that within a conductor there is no charge, and this has been proved correct. The principle is used to make metal jump suits to be worn by electrical engineers working on high tension electricity cables.
Research Faraday Cage
Following explosions in mines caused by miner's candles, a society was formed in 1813 to study methods of preventing these explosions and approached Sir Humphry Davy for advice. Humphry Davy investigated the problem and designed the safety lamp. In its original form the safety lamp was an oil burner completely surrounded by a cylinder of wire gauze. Becaue the gauze threw undesirable shadows, the design was modified and athick cylindrical glass window was added, still retaining the gauze above but encased in a brass shroud. Should the atmosphere surrounding the lamp contain methane, its presence will be indicated by the flame becoming surrounded by a luish haze. The flame cannot extend beyond the gauze and cause an explosion, since the wires of the gauze rapidly conduct the heat away, and the temperature of the gauze never rises to the ignition point of the gas-air mixture in the mine.
Research Miner's Safety Lamp
Barege is a gauze-like fabric used for women's dresses, made of silk and worsted, or of cotton and worsted.
Research Barege
Gauze is a thin transparent stuff of silk, linen, or cotton. It is either plain or figured, the latter being sometimes worked with flowers of silver or gold.
Research Gauze
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The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
©1993 - 2009 The Probert Encyclopaedia
Southampton, United Kingdom
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