SIGMOID GUT [colon sigmoideum (PNA, BNA); colon sigmoides (JNA); synonym: S-shaped gut, S-romanum, sigma] — the part of a large intestine which is continuation of the descending colon and passing into final department of intestines — a rectum.
Sigmoid gut (sigmoid colon, T.) is in the left ileal and pubic areas of an abdominal cavity and partially in a small basin (fig). It begins at the level of an ileal crest and in a small basin at the level of the third sacral vertebra passes in rectum (see). Page to. it is covered with a peritoneum from all directions, has a mesentery (mesocolon sigmoideum) width on average to 16 cm and differs in considerable mobility. In front of S. to. prilezhit to a front abdominal wall, behind — to ileal and big lumbar to muscles, ileal vessels and a sacrum, it is above and on the right there are loops of a small bowel, below — bladder (see), at women — uterus (see).
At adult S. to. has length from 15 to 67 cm (on average 54 cm); diameter of its gleam apprx. 4 cm, thickness of walls — 2 — 2,5 mm. Length of a gut depends on specific features and age. At children it is the longest department of a large intestine. Page to. forms two loops: upper (colon iliacum) — the proximal, turned by camber from top to bottom, borrowing generally left ileal pole, and lower (colon pelvicum) — distal, turned by camber up, longer, being in a small basin. Right-hand localization of loops is often observed.
S.'s blood supply to. it is carried out by 2 — 5 sigmoid arteries (aa. sigmoideae), to-rye are branches of the lower mesenteric artery (a. mesenterica inf.). Sigmoid arteries are divided into branches and anastomose with branches of the next arteries, forming arcades. The branches creating the artery passing at mesenteric edge along a gut depart from them. The direct arteries covering a gut on both sides and connecting among themselves at its free edge depart from this artery. The upper sigmoid artery anastomoses with the left colonic artery (a. colica sin.), lower — with an upper pryamokishechny artery (a. rectalis sup.).
Veins S. to. accompany arteries. Outflow of a venous blood happens in two directions: on the lower mesenteric vein (v. mesenterica inf.) in a portal vein (v. portae) and on veins of a pryamokishechny veniplex (plexus venosus rectalis) in the lower vena cava (v. cava inf.).
Limf, S.'s vessels to. accompany blood vessels and go to sigmoid limf, nodes (nodi lymphatici sigmoidei) and lower mesenteric limf, to nodes (nodi lymphatici mesenterici inf.), lying at the beginning of the lower mesenteric artery.
S.'s innervation to. it is carried out by branches of the lower mesenteric texture (rr. mesentericus inf.).
Comparative anatomy, embryology, histology and physiology — see. Intestines .
Methods of inspection
At poll of the patient need to be established the postponed diseases, character of abdominal pains, their communication with meal, time of day, the frequency of defecation, feature of fecal masses. At survey stomach (see) at the patient with S.'s pathology to. it is possible to see a hyperperistalsis of intestines (at impassability), protrusion of an abdominal wall (at big new growths, especially at the exhausted patients). At a palpation of a front abdominal wall it is possible to reveal patholologically the changed S. to. From tool methods apply endoscopic (see. Kolonoskopiya , Peritoneoskopiya , Rektoromanoskopiya ) and X-ray inspection (see. Angiography , Irrigoskopiya ).
Patol. processes in S. to., as a rule, do not happen isolated; they are usually connected with diseases of other departments of a large intestine. Allocate malformations of S. to. (see. Megacolon , Splanchnomegaly , Splanchnoptosia ), damages (see. Stomach ), functional diseases (see Intestines), inflammatory diseases (see. Colitis , Krone disease , Sigmoiditis , Ulcer nonspecific colitis ), infectious diseases with S.'s defeat to. (see. Actinomycosis , Amebiasis , Dysentery , Syphilis , Tuberculosis ), new growths (see. Fleecy tumor , Polyp, polyposes ; Cancer ), a divertuculosis, a diverticulitis (see Intestines), and also some other diseases — mega a dolichosigma, torsion, intestinal fistulas (see), etc.
Megadolikhosigma — lengthening and expansion C. to.; can be inborn (see. Megacolon ) and acquired. The acquired megadolichosigma is a consequence of a mechanical obstacle at the inborn and acquired narrowings of a rectum, and also its damages.
A wedge, manifestations — persistent (to 2 — 3 weeks) locks (see), not giving in to conservative treatment and allowed only after mechanical clarification of a rectum. The stomach at the patient of the big sizes, is blown up, has rounded shape. Skin of a front abdominal wall is stretched, the venous network on it is expanded, the peristaltic movements of intestinal loops can be visible. At a deep palpation it is possible to define accumulation a calla in a large intestine. The symptom of formation of a pole is characteristic: during the pressing by a finger through a front abdominal wall on the dense fecal masses which is in a gut, as a rule, arises resistant in pressure.
The diagnosis is made on the basis of data of the anamnesis (long locks), by a wedge, pictures, results rentgenol. researches (with administration of contrast medium both through a rectum, and through a mouth). Before rentgenol. a research it is necessary to clear a large intestine by means of siphon enemas (see).
Treatment can be conservative (a diet, regular reception of purgatives, cleansing enemas, power tool cleaning of a gut), and at its inefficiency — operational (S.'s resection to.).
The forecast at regular and careful bowel emptying favorable.
Torsion of a sigmoid gut most often arises owing to its impassability. In an etiology of torsion of S. to. the large role is played by a condition of its mesentery: wrinkling and cicatricial deformation of a mesentery (especially with its considerable length) causes rapprochement of the ends of S. to., what promotes stretching and lengthening of a gut and results in stagnation of contents in it. P redraspol the agayushchy moments to S.'s torsion to. there can be an increase in intra belly pressure (a big and sudden exercise stress), strengthening of a vermicular movement of intestines after acceptance of a large number of the food rich with a rough cellulose, long locks. Torsion arises owing to turn C. to. and its mesenteries round its pivot-center.
The beginning of a disease acute — sharp colicy pains in a stomach, the termination of an otkhozhdeniye a calla and gases, the accruing abdominal distention. At a physical research find the asymmetry of a stomach stenosing a peristaltics of intestines, capotement. At a manual research of a rectum the gaping of an anus, expansion of an ampoule of a rectum (a symptom of the Obukhovsk hospital) is found. At S.'s torsion to. Tsege-Manteyfel's symptom is characteristic: by means of an enema it is possible to enter 1 — 2 glass of water, edges quickly follows, the calla does not contain impurity, there is no passage of flatus at the same time. The vomiting which developed in the beginning then can stop and renews in connection with development of peritonitis again. The general condition of the patient remains satisfactory in the beginning, however in process of increase of impassability of intestines and development of peritonitis worsens.
The diagnosis is made on the basis of data of the anamnesis, clinical, endoscopic and rentgenol. researches (see Impassability of intestines).
Treatment in the beginning conservative — novocainic blockade, a siphon enema, intubation (see). In the absence of positive effect from conservative actions the operative measure consisting, as a rule, in a turn (detorsiya) of S. to is shown. or, if the gut is impractical, its resections with imposing of a temporary or constant unnatural anus (see. Anus praeternaturalis ).
Operations on S. to. carry out under an endotracheal anesthesia (see. Inhalation anesthesia ) using muscle relaxants (see). Preoperative preparation and postoperative maintaining — see. Intestines, operations . Access to S. to. is median laparotomy (see).
S.'s resection to. concerning cancer, intestinal impassability under favorable conditions and at full confidence in viability of intestinal loops the end in the end can come to an end with imposing of an intestinal anastomosis (see. Intestines , Intestinal seam ). At uncertainty in viability of the distal and proximal ends of a gut after S.'s resection to. imposing of an unnatural anus is shown. The extirpation of a rectum is also usually finished with imposing of a sigmostoma (see. Sigmoidostomy ). At a diverticulitis, nonspecific ulcer colitis and a disease Krone with S.'s defeat to. it can be executed hemicolectomy (see) or colectomy (see).
Bibliography: Baulin A. A. About features of blood supply of a wall of a colonic and sigmoid gut, Vestn. hir., t. 112, No. 3, page 128, 1974; Blood supply of bodies of a digestive tract of the person, under the editorship of K. I. Kulchitsky and I. I. Bobrik, Kiev, 1970; Malysheva E. P. Absorbent vessels of a sigmoid gut of the person, in book: The general patterns of a morphogenesis and regeneration, under the editorship of K. I. Kulchitsky, etc., century 2, page 128, Kiev, 1970; Melman E. P. Functional morphology of an innervation of digestive organs, M., 1970; P. A Novels. Forms of a colonopexy at the adult, Surgery, No. 2, page 59, 1980; Surgical anatomy of a stomach, under the editorship of. And. N. Mak-simenkova, page 587, D., 1972; Abdomen, ed. by A. Alavia. P. H.Arger, v. 3, N. Y., 1980; Lawson J. O. Pelvic anatomy, Ann. roy. Coll. Surg. Engl., y. 54, p. 288, 1974; Parrott D. M. The gut as a lymphoid organ, Clin. Gastroent., v. 5, p. 211, 1976; Shackleford R. T. Operative anatomy of abdomen and pelvis, Arch. Surg., v. Ill, p. 834, 1976.
G. A. Pokrovsky; H. V. Krylova (An.).