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 distalloop. 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 glassrod passed through a small hole in the mesentery. The ends of the glassrod 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 tullegras is applied on the exposed bowel. The skin incision may be sealed with Whitehead's varnish and a pad of cellulosetissue 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 mucousmembrane 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
A rifle is a firearm with spiral, parallel grooves cut into the bore to impart spin in the projectile giving flight stability to the projectile, and thus greatly improves the accuracy with which the projectile follows the aim.
Rifled firearms existed in the Middle Ages, but didn't appear in wars until about the middle of the 17th century. They were not introduced into the British army until 1800, when the Baker rifle was issued. The problem encountered by early rifles was of manufacturing bullets which would fit the barrel tightly. The first improvement of any consequence was devised by Delvigne, a French officer, in 1826. At the breech end of the rifle was a chamber, of smaller diameter than the bore, to receive the charge of powder. But this did not prove satisfactory in practice. Delvigne suggested, further, the first cylindro-conical bullet. At that time, however, this was found not be the answer. Meanwhile the Brunswick rifle had succeeded the Baker. It had two grooves, and fired a spherical projectile with a narrow projecting ring or ' belt' around it, which was meant to take the grooving. It was necessary to place the bullet in a particular position in loading, so that the belt should touch the bore all round, and this caused considerable delay in loading. The Brunswick rifle also fouled very quickly, and was not accurate beyond 365 metres.
The first person to hit on the idea of causing the expansion of the bullet by the force of the explosion of the charge, and thus abolishing the crude method of expanding it by blows from the ramrod, was the English gun-maker Greener. In 1836 he proposed an egg-shaped bullet with an opening at one end, into which a separate taper plug entered. The explosion of the powder drove the plug into the bullet, and so caused it to expand at the base and fill the grooves. This principle was applied by Delvigne to an elongated bullet with a hollow base in 1841. the French war ministry adopted Thouvenin's 'tige' rifle in which a 'tige,' or pillar, served as a kind of anvil on which to crush out the bullet into the grooves by blows from the ramrod. In 1847 CaptainMinie, of the French army, introduced an improvement in the bullet, into the hollow base of which he inserted a hemispherical iron cup, which being pushed up the cavity by the force of the explosion of the charge, improved its expansion. A rifle of the Minie pattern was used in the Kaffir war of 1851 and in the earlier part of the Crimean campaign. But in 1855 it was superseded by the Enfield rifle. This weapon was of two patterns, the long and the short; the former which was issued to the infantry of the line, had three grooves; the short rifle had five grooves, and a sword-bayonet. The original Enfield rifle fired a bullet without cup or plug in its base, but the Minie iron cup was afterwards added. This subsequently gave way to a boxwood plug, which again was superseded in 1863 by a plug of baked clay. The Lancaster rifle came into the field at about the same period as the Enfield. Instead of grooves, this rifle had a smooth, spiral, elliptical bore of increasing twist. It was adopted in 1855 for the sappers and miners. In 1858 an improved short Enfield rifle was issued to the rifle regiments and to sergeants of line infantry, as well as to the royal navy.
In 1853 Sir Joseph Whitworth invented a rifle of which the bore was hexagonal, and which could fire either cylindrical or hexagonal projectiles. But although it gave better results than the Enfield, it was not adopted by the War Office. The next great change in military rifles was the general adoption of breech-loading. As early as 1848 Prussia alone of all European nations had armed her troops with the breech-loading Dreyse Needle Fire Rifle, pattern 1841. In this rifle the bolt which closed the breech contained a needle, which, on a spring being released, pierced the paper cartridge-case containing the powder, and struck the detonating composition placed between it and the base of the bullet, so that the ignition of the charge took place between the powder and the bullet, the idea being to prevent any of the powder being driven up the barrel with the bullet, and thus igniting in a larger space, and consequently with reduced force. The effects produced by the Needle Fire Rifle in the Danish war of 1864 caused all nations to decide on adopting breech-loading firearms, and the Prussian successes against Austria in 1866 stimulated the movement. England and France were the first to adopt the system in 1866; they were followed by Russia, Denmark, Sweden and Belgium in 1867, and by Austria and Italy in 1868.
The French adopted a new rifle, the Chassepot, an improved needle fire rifle, with which a paper cartridge was used similar in principle to the Prussian. In England the Enfield rifles were converted into breech-loaders. Finally, Snider's pattern was accepted, and the converted Enfield became known as the Snider rifle. According to the means used for closing the breech, breech-loading firearms are divided into two main classes - the 'bolt' system and the ' block' system. The PrussianNeedle Fire Rifle was fitted with a bolt mechanism, as also was the Chassepot. the Snider was given a block breech action, and in England it was determined ultimately that a block breech action was preferable to a bolt action. In 1869 the committee recommended the adoption of a combination of the block-action breech mechanism, invented by Martini with Henry's barrel, and the rifle was christened the Martini-Henry. In this weapon the breech action was a block which, pivoting on its rear end, sank to admit the cartridge. The block was moved by means of a lever beneath the breech, the forward action of which caused it to sink, and then extracted the empty case of the previously fired cartridge. the backward movement of the lever pushed up the block, and thus closed the breech. Germany replaced the Needle Fire Rifle with the Mauser rifle in 1871; Italy which had armed her infantry with Carcano rifle of 1868, abandoned it for the Vetterli, also in 1871; Austria which had adopted the Werndl in 1868, modified it in 1873; in 1874 France discarded the Chassepot for the Gras; the Russian Berdan of 1871 was improved in pattern in 1880. All these rifles, except the Werndl, had a bolt breech action. The next great departure in the history of military rifles was the introduction of the magazine. The idea of repeating firearms had been current in America since 1840, when Colt brought out his invention. His rifle was followed in 1860 by the Henry and the Spencer. In 1867 the Henry had been improved
renamed the Winchester. the effects of the Winchester in the hands of the Turks in their war with Russia of 1877 to 1878 showed the immense advantage of repeating firearms against an enemy armed with single-loading rifles. The earliest European repeating rifle was the Fruhwirth, with which Austria armed her gendarmerie in 1870. In 1878 the French supplied their marines with the Kropatschek magazine which had been adapted to the Gras rifle. The advantages of reducing the calibre of military rifles, and of using a lighter though comparatively longer bullet, were urged by Major Rubin of the Swiss army as early as 1883. the chief of these advantages are to increase the flatness of the trajectory, the range, the accuracy, and the penetration of the projectile, while recoil is diminished. Research Rifle
Abbreviations
Research Colostomy
