pathogenetic mechanisms of development of constipations at children

For understanding of a pathogenesis of chronic constipations the knowledge of the processes underlying a normal defecation [91] is necessary. In the defecation certificate

The complex of mechanisms and anatomic structures which muscles tazovogo concern bottoms a rectum, group of muscles of an internal and external proctal sphincter, and also independent and vegetative nervous system, a brain cortex takes part.

The important role in the normal certificate of a defecation play rising of intraabdominal pressure as a result of reduction of muscles of an abdominal wall and a phrenoptosis, a relaxation internal and external proctal sphincters [129, 130]. External and internal sphincters,

Surrounding the proctal channel, and a bosom-prjamokishechnaja a muscle form an anorectal angle which in rest makes 80-105 °.

At the defecation certificate fecal masses get into a rectum and adjoin to a mucosa, irritating nervous receptors. The rectum stretching, pressure rising in it and a boring of receptors cause a relaxation of an internal proctal sphincter that leads to desire occurrence on a defecation. Thus the external proctal sphincter remains closed. The defecation occurs any way under the control of a cortex of a brain. At a defecation lonno-prjamokishechnaja the muscle is relaxed, tazovoe the bottom falls, the anorectal angle is enlarged, the external proctal sphincter is relaxed and there is an excision of fecal masses. At newborn and thoracal children influence of a cortex of a brain is absent, and the defecation certificate occurs at a relaxation of an internal proctal sphincter [142].

4 types of the reductions causing movement of fecal masses on an intestine [62, 68] are described:

• the Segmenting movements representing local reductions with frequency more 12 in minute which mix fecal masses, but do not promote their advancement on an intestine.

• Peristaltic reductions carry out contents advancement


• the Masso-reductions arising to 4 times a day which cover the most part of an intestine and provide it oporozhnenie.

• Antiperistaltic reductions move intestine contents in the opposite direction.

Weakening peristaltic and masso-reductions causes difficulty oporozhnenija an intestine. Prevalence of segmenting reductions causes a fragmentation of a chair and a painful syndrome. Hyper-and hypomotor disturbances of a peristalsis of an intestine can be isolated or to be combined with disturbances of a defecation and receptor sensitivity of an intestine. Delicacy of intraabdominal pressure does not allow to carry out pressure upon an intestine and to stimulate a peristalsis [59].

In a pathogenesis of constipations it is possible to allocate some moments [81, 121, 124, 132, 143]:

1. Retardation of advancement of fecal masses on an intestine. As prospective mechanisms of retardation of transit it is surveyed:

o number Depression vysokoamplitudnyh "pushing" peristaltic reductions of a colon. This type of peristaltic movements also is responsible for contents advancement on an intestine lumen.

o quantity Augmentation not koordinirovannyh peristaltic reductions in distal department of a colon that frames a functional barrier to contents transit.

2. The constipations bound to dysfunction of muscles tazovogo of a bottom. In this case time of transit of contents on an intestine is not changed, but the clump and a delay contained in a rectum is observed.

The basic problem is disability to carry out adequate evacuation of contents from a rectum - anorectal dysfunction. Exact
The pathophysiological mechanism of this disorder is studied now insufficiently. However two subtypes of the given disturbances are allocated:

o the Muscular hypertonus - an incomplete relaxation or paradoxical konstriktsija muscles tazovogo a bottom and a proctal sphincter at defecation attempt.

o the Muscular hypotonus.

3. Constipations in which basis the combination of both above described mechanisms lays.

Electric activity of a colon differs from enteric lower and variabelnoj amplitude of slow waves of muscular reductions. J.D.Huizinga and co-authors have shown, that food intake raises, and the dream reduces motor activity of a colon [105].

At early age in connection with immaturity of nervously-reflex communications and intramuralnoj nervous system of a colon, formation of the mechanism of the certificate of a defecation occurs gradually under the influence of factors of environment and specific features of an organism of the child. "Ripening" occurs gradually within the first months of a life, and full formation comes to an end on 2 - 3 year of a life. Immaturity reguljatornyh mechanisms can serve as the reason of that various adverse factors (toxins, medicinal preparations, stresses, intestinal infections) can easily break a motility and oporozhnenie an intestine.

Chair accumulation in a rectum causes gradual expansion of the proctal channel, and to megarectum formation that conducts to loss of rectal sensitivity and a desire to a defecation. It has been shown, that at children with a megarectum the high sensory threshold is necessary for rectum stimulation [84, 148].

The essential role in regulation of a motility of a colon is played by hormones GASTROINTESTINAL TRACT which co-operate with cells-targets, and also with the nervous
The terminations and gladkomyshechnymi cells: vazointestinalnyj a peptide, motilin, substance R, a serotonin, Histaminum, a glucagon.

A number of researchers notice, that the important role in development of constipations is played by absence of a continuity of connective tissue structures that leads to depression of frequency and force of reductions of a wall of an intestine with development of a megacolon in the absence of disturbances of its vegetative innervation [31].

Considering, that the constipation at 95 % of children has functional character [131, 137], since 2006 for diagnostics of the given pathology use the Roman criteria III in which the following algorithm of an establishment of the diagnosis of a constipation at children at the age from 4 till 18 years [140] is offered.

Constipation symptoms should be observed not less than 2 months and their quantity should be not less than 2 of more low listed provided that there are not enough criteria for diagnosing of a syndrome of an angry intestine [140]:

The quantity of defecations - 2 and is more rare in a week

At least, 1 episode of an incontience of a feces in a week

Presence of episodes of a keeping pose or the long conscious

Chair keeping

Presence of episodes of pains or gravity in a stomach

Presence of great volume of fecal masses in a rectum

Presence of episodes of a chair of the big diameter which can cork a drain

Toilet bowl

At children of advanced age and at adults use the Bristol scale which includes 7 types of a chair: from "sheep" time of transit of fecal masses caused by elongation on an intestine, to liquid watery when transit time is sharply reduced. Normal for the child variants of 3rd and 4th are considered: a chair in shape "kolbaski" with a ridge surface or in shape "kolbaski" ("snakes"), smooth and soft [104].

For children of early age it is offered to use the Amsterdam scale of an estimation of a chair - scale Bekkali which describes a chair consistence (on 4 points), quantity of a chair (on 4 points) and colour of a chair (6 categories). The scale is convenient for application both at full-term, and at not full-term children [83].


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Scientific source IPATOV ANDREY ALEKSANDROVICH. EFFICIENCY of ACUPUNCTURE In COMPLEX TREATMENT of CHILDREN With the CONSTIPATION SYNDROME. The DISSERTATION on competition of a scientific degree of the candidate of medical sciences. Moscow - 2014. 2014

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