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Reasons of a gastrostaz
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In recent years interest of doctors in disturbances of motility of a stomach amplified. Identification and treatment of syndromes of a gastrostaz is based on clinical diagnosis, these radio isotope and electrophysiologic researches, and also on modern achievements of pharmacotherapy. From physiology positions the stomach can be divided into two parts, each of which carries out processing and evacuation of a liquid or firm component of food. Modern diagnostic methods, for example research of motility of a stomach with use of double isotope tags, allow to track separately evacuation of a liquid and solid phase of food and to reveal motility disturbance mechanisms. Pathophysiological researches of electrophysiologic aspects of function of a stomach which can lead to new opening in this area are conducted. Revival of interest in disturbances of motility of a stomach substantially is explained by implementation of the new highly effective means improving evacuation, in particular Metoclopramidum and a domperidon (domperidon).
Process of evacuation of a stomach can be considered separately for liquid and firm food as carry out its different departments of a stomach. The bottom and proximal part of a body of a stomach carry out evacuation function first of all of a liquid phase at the expense of a pressure gradient between a stomach and a duodenum which is created at reduction of a stomach (fig. 1). Due to elasticity of proximal part of a stomach in it large volume of food without essential increase of intragastric pressure can accumulate. This state is called a receptive or adaptive relaxation. Trunk, superselection, or parietal and cellular vagisection *, eliminates this reflex that leads to fast evacuation of liquid food.
* Further the superselection, nl parietal and cellular, vagisection is called "proximal selection vagisection", i.e. the standard term.
Fig. 1. Evacuation of liquid and firm food from a stomach.
Peristaltic reductions turn solid particles of food into semi-fluid masses.
Evacuation of a solid phase of food is function of distal departments of a stomach. Reductions of a ring of muscle fibers amplify towards the gatekeeper, squeezing out in it the firm food mixed with pepsin and the hydrochloric acid cosecreted by proximal part of a stomach. Through the gatekeeper there do not pass food particles more largely than 0,5 mm therefore in the beginning lumps of firm food come back. Such roundabout and hashing of food proceeds until the homogeneous chyme suitable for evacuation is formed.
Control of evacuation from a nervous system is exercised at the expense of an efferent innervation by fibers of a vagus nerve (promoting effect) and sympathetic nerves (the braking action). Also participation in the mechanism of evacuation and dopaminergic specific brake mechanisms is supposed. In a middle part of a body of a stomach on big curvature the pacemaker of gastric reductions is located. It develops the rare potentials (3 — 4 in min.) extending distally. The pacemaker regulates the frequency and speed of reductions of distal part of a stomach which are generated independently (see fig. 1).
Motility of a stomach on an empty stomach differs from motility of a full stomach in existence of the motor complexes extending from a stomach to an ileal gut. Each of them consists of four phases. Activity of the III phase which proceeds 5 — 15 min. is equal to 3 reductions a minute which push the particles which remained undigested through open the gatekeeper. These motor complexes are called "janitors" of a digestive tract.
Disturbances of motility of antral department lead to delay of evacuation of a solid phase of food while liquid evacuation generally does not suffer as the gradient remains
pressure between a stomach and a duodenum. Theoretically disturbances of motility of proximal department of a stomach have to cause a delay of both a liquid, and solid phase as the pressure gradient causing passing through the gatekeeper of the semi-fluid chyme processed in a stomach decreases. Nevertheless clinically isolated disturbances of evacuation of liquid food did not manage to be established though staz firm food owing to the isolated disturbances of motility of antral part of a stomach it is well-known. Nevertheless the combined disturbances of evacuation of liquid and firm food are observed, usually at serious or advanced diseases, for example at diabetic paresis of a stomach. On the other hand, cases of the accelerated evacuation of liquid food ("dumping") in combination with delay of evacuation of firm food are known, for example, at a gastrostaza after partial resections of a stomach with an anastomosis according to Billroth-I or Billroth of II.
Symptomatology of a gastrostaz
The syndrome of a gastrostaz is usually shown by characteristic combinations of symptoms. Sometimes the patient can point only to one or two signs disturbing him. Most often there are complaints to nausea and vomiting. Some patients with the broken evakuatorny function complain only of an eructation and feeling of overflow after food that is caused probably by accumulation of food in the stretched stomach. Anorexia and early the coming feeling of saturation usually are connected with constitutional features, but in combination with the symptoms stated above can be a sign of a gastrostaz. Abdominal pains are observed sometimes at a gastrostaza, and probably too are connected with stretching, but their emergence has to guard the doctor and induce it to searches of anatomic disturbances in a stomach or in surrounding bodies which can be the cause of a gastrostaz. Treat such disturbances: stomach ulcer, the penetrating ulcer of a back wall of a duodenum, a carcinoma of the stomach, indurative (pancreatitis, diseases of bilious ways, the "angry" stomach, perhaps, caused by gastritis or a viral infection, and also a pancreatic cancer.
Clinical examination can not reveal pathologies or find only protrusion in epigastriums or overflow of a stomach. The capotement characteristic of obstruction of an exit from a stomach, can be found at a gastrostaza, especially, if there is a considerable delay of evacuation of liquid. Perhaps, though it is rare, detection of morbidity at a palpation in epigastriums. Sometimes at endoscopy or at roentgenoscopy the bezoar which can indicate an evacuation delay is found.