Violation of the peripheral innervation of the bladder. Urination disorders

An important link in the process of urination is the occurrence of the urge to defecate. The work of this mechanism is provided by innervation Bladder Numerous nerve endings of the organ timely supply the signals necessary for the body. Violation of the nervous system can also lead to dysfunction of emptying. You can understand the relationship of structures by considering the mechanism for excreting urine.

Urination algorithm

The average bladder volume is 500 ml. A little more in men (up to 750 ml). In women, as a rule, it does not exceed 550 ml. The continuous work of the kidneys ensures the periodic filling of the organ with urine. Its ability to stretch the walls allows urine to fill the body up to 150 ml without discomfort. When the walls begin to stretch and the pressure on the organ increases (usually this occurs when urine is formed in excess of 150 ml), the person feels the urge to defecate.

The reaction to irritation occurs at the reflex level. At the point of contact between the urethra and the bladder, there is an internal sphincter, a little lower one is an external one. Normally, these muscles are compressed and prevent the involuntary release of urine. When the urge to get rid of urine occurs, the valves relax, which ensures that the muscles of the organ that accumulates urine contract. This is how the bladder is emptied.

Bladder innervation model

The connection of the urinary organ with the central nervous system It is provided by the presence in it of sympathetic, parasympathetic, spinal nerves. Its walls are equipped with a large number of receptor nerve endings, scattered neurons of the autonomic nervous system and nerve nodes. Their functionality is the basis for stable controlled urination. Each type of fiber performs a specific task. Violations of innervation lead to various disorders.

Parasympathetic innervation

The parasympathetic center of the bladder is located in the sacral region of the spinal cord. From there originate preganglionic fibers. They take part in the innervation of the pelvic organs, in particular, form the pelvic plexus. The fibers stimulate the ganglia located in the walls of the organ of the urinary system, after which its smooth muscle contracts, respectively, the sphincters relax, and intestinal peristalsis increases. This ensures emptying.

Sympathetic innervation

The cells of the autonomic nervous system involved in urination are located in the intermediate lateral gray column of the lumbar spinal cord. Their main purpose is to stimulate the closure of the cervix, due to which there is an accumulation of fluid in the bladder. It is for this that sympathetic nerve endings are concentrated in large numbers in the triangle of the bladder and neck. These nerve fibers have practically no effect on motor activity, i.e., the very process of the exit of urine from the body.

Role of sensory nerves

The reaction to the stretching of the walls of the bladder, in other words, the desire to have a bowel movement, is possible due to the afferent fibers. They originate in the proprioreceptors and noniceptors of the organ wall. The signal through them goes to the segments of the spinal cord T10-L2 and S2-4 through the pelvic, pudendal and hypoastral nerves. So the brain receives an impulse about the need to empty the bladder.

Violation of the nervous regulation of urination

Violation of the innervation of the bladder is possible in 3 variants:

1. Hyperreflex bladder - urine stops accumulating and is immediately excreted, and therefore the urge to go to the toilet is frequent, and the volume of fluid released is very small. The disease is a consequence of damage to the central nervous system.
2. Hyporeflex bladder. Urine accumulates in large quantities, but its exit from the body is difficult. The bubble is significantly overfilled (up to one and a half liters of fluid can accumulate in it), inflammatory and infectious processes in the kidneys are possible against the background of the disease. Hyporeflexia is determined by lesions of the sacral part of the brain.
3. Areflex bladder, in which the patient does not affect urination. It occurs by itself at the moment of maximum filling of the bubble.

Such deviations are determined by various reasons, among which the most common are: craniocerebral injuries, cardiovascular diseases, brain tumors, multiple sclerosis. To identify pathology, relying only on external symptoms, is quite problematic. The form of the disease directly depends on the fragment of the brain that has undergone negative changes. The term "neurogenic bladder" has been introduced in medicine to refer to dysfunction of the urine reservoir due to nervous disorders. Different kinds lesions of nerve fibers in different ways disrupt the excretion of urine from the body. The main ones are discussed below.

Brain damage that disrupts innervation

Multiple sclerosis affects the work of the lateral and posterior columns of the cervical spinal cord. More than half of patients experience involuntary urination. Symptoms develop gradually. Sequestration intervertebral hernia on the initial stage causes urinary retention and difficulty emptying. This is followed by symptoms of irritation.

Supraspinal lesions of the motor systems of the brain disable the urination reflex itself. Symptoms include urinary incontinence, frequent urination, and nocturnal bowel movements. However, due to the preservation of the coordination of the work of the basic muscles of the bladder, it retains required level pressure, which eliminates the occurrence of urological ailments.

Peripheral paralysis also blocks reflex muscle contractions, causing an inability to relax the lower sphincter on its own. Diabetic neuropathy causes detrusor dysfunction in the bladder. Stenosis of the lumbar spine affects the urinary system according to the type and level of the destructive process. With cauda equina syndrome, incontinence is possible due to overflow of a hollow muscular organ, as well as a delay in the excretion of urine. Hidden spinal dysraphism causes a violation of the reflection of the bladder, in which a conscious bowel movement is impossible. The process occurs independently at the moment of maximum filling of the organ with urine.

Options for dysfunction in severe brain damage

The syndrome of complete interruption of the spinal cord is manifested by such consequences for the urinary system:

1. In the case of dysfunction of the supra-sacral segments of the spinal cord, which can be caused by tumors, inflammation or trauma, the mechanism of damage is as follows. Development begins with detrusor hyperreflexia, followed by involuntary contractions of the bladder and sphincter muscles. As a result, intravesical pressure is very high and the volume of urine output is very small.
2. When the sacral segments of the spinal cord are affected due to injuries or disc herniation, on the contrary, there is a decrease in the frequency of emptying and a delay in the release of urine. A person loses the ability to independently control the process. Involuntary leakage of urine occurs due to overflow of the bladder.

Diagnosis and treatment of the disease

Changes in the frequency of bowel movements are the first signal for examination. In addition, the patient loses control over the process. Diagnosis of the disease is carried out only in a complex: the patient is given an x-ray of the spine and skull, the abdominal cavity, they can prescribe magnetic resonance imaging, ultrasound of the bladder and kidneys, general and bacteriological blood and urine tests, uroflowmetry (recording the speed of urine flow during the usual act of urination), Cytoscopy (examination of the inner surface of the affected organ).

There are 4 methods to help restore the innervation of the bladder:

• Electrical stimulation of the urinal, groin muscles and anal sphincter. The goal is to activate the reflection of the sphincters and restore their common activity with the detrusor.
• The use of coenzymes, adrenomimetics, cholinomimetics and calcium ion antagonists to activate the efferent links of the autonomic nervous system. Indicated drugs for taking: "Isoptin", "Ephedrine hydrochloride", "Aceclidin", "Cytochrome C".
• Tranquilizers and antidepressants restore and support autonomic regulation.
• Calcium ion antagonists, cholinergic, anticholinergic drugs, a-andrenostimulators restore the patient's ability to control urine output, normalize the retention of urine in the bladder, and regulate the smooth functioning of the sphincter and detrusor. Atropine sulfate, Nifedipine, Pilocarpine are prescribed.

Bladder innervation can be restored. Treatment depends on the extent and nature of the lesion and can be medical, non-pharmacological and surgical. It is extremely important to observe a sleep schedule, regularly walk in the fresh air, and perform a set of exercises recommended by doctors. Restore innervation with folk remedies impossible at home. In order for the disease to be treated, it is necessary to follow all the prescriptions of the attending physician.

In the neurological clinic, dysfunctions of the pelvic organs (disorders of urination, defecation and genital organs) are quite common.

Urination is carried out by the coordinated activity of two muscle groups: m. detrusor urinae and m. sphincter urinae. The contraction of the muscle fibers of the first group leads to compression of the bladder wall, to the extrusion of its contents, which becomes possible while relaxing the second muscle. This happens as a result of the interaction of the somatic and autonomic nervous systems.

The muscles that make up the internal sphincter of the bladder and m. detrusor vesicae, consist of smooth muscle fibers that receive autonomic innervation. The external urethral sphincter is formed by striated muscle fibers and is innervated by somatic nerves.

Other striated muscles also take part in the act of voluntary urination, in particular the muscles of the anterior abdominal wall, the diaphragm of the pelvic floor. The muscles of the abdominal wall and diaphragm, when tensed, cause a sharp increase in intra-abdominal pressure, which complements the function of m. detrusor vesicae.

The mechanism of regulation of the activity of individual muscle formations that provide the function of urination is quite complex. On the one hand, at the level of the segmental apparatus of the spinal cord, there is autonomic innervation of the smooth fibers of these muscles; on the other hand, in an adult, the segmental apparatus is subordinate to the cerebral cortical zone and this is the voluntary component of the regulation of urination.

Schematically, the innervation of the bladder can be depicted as follows.

In the act of urination, 2 components can be distinguished: involuntary-reflex and arbitrary. The segmental reflex dut consists of the following neurons (Fig. 85): afferent part - cells of the intervertebral node S I - S III dendrites end in the proprioreceptors of the bladder wall, are part of the pelvic splanchnic nerves (nn. splanchnici pelvini), pelvic nerve - nn. pelvici (BNA), axons go in the posterior roots and spinal cord, contact with the cells of the anterolateral part of the gray matter of the segments of the spinal cord S I - S III (spinal center of parasympathetic innervation of the bladder). The fibers of these neurons, together with the anterior roots, exit the spinal canal and, as part of the pelvic nerve (N. pelvicus), reach the bladder wall, where they are interrupted in the cells of pl. vesicalis. The postsynaptic fibers of these intramural parasympathetic nodes innervate smooth muscles m. detrusor vesicae and partially internal sphincter. Impulses along this reflex arc lead to a contraction of m. detrusor vesicae and relaxation of the internal sphincter.

Sympathetic cells that innervate the bladder are located at the level of L I - L II segments of the spinal cord. The fibers of these sympathetic neurons, together with the anterior roots, leave the spinal canal, then separate in the form of a white connecting branch and pass without interruption through the lumbar nodes of the sympathetic trunk, as part of the mesenteric nerves, reach the inferior mesenteric node, where they switch to the next neuron. Postsynaptic fibers in n. hypogastricus approach the smooth muscles of the bladder.

Rice. 85. Innervation of the bladder and its sphincters (diagram):

1 - pyramidal cell of the cortex of the paracentral lobule; 2 - cell of the nucleus of a thin bundle; 3 - sympathetic cell of the lateral horn L I - II; 4 - cell of the spinal node; 5 - parasympathetic cell of the lateral horn S I - III; 6 - peripheral motor neuron; 7 - genital nerve; 8 - cystic plexus; 9 - external sphincter of the bladder; 10 - internal sphincter of the bladder; 11 - hypogastric nerve; 12 - bladder detrusor; 13 - lower mesenteric node; 14 - sympathetic trunk; 15 - cell of the thalamus; 16 - sensitive cell of the paracentral lobule.

The role of efferent sympathetic fibers is limited to the regulation of the lumen of the blood vessels of the bladder and the innervation of the muscle of the cystic triangle, which prevents ejaculate from entering the bladder at the time of ejaculation.

Automatic emptying of the bladder is provided by two segmental reflex arcs (parasympathetic and somatic). Irritation from stretching its walls along the afferent fibers of the pelvic nerve is transmitted to the spinal cord to the parasympathetic cells of the sacral segments of the spinal cord, impulses along the efferent fibers lead to a contraction of m. detrusor vesicae and relaxation of the internal sphincter. The opening of the internal sphincter and the flow of urine into the initial sections of the urethra include another reflex arc for the external (striated) sphincter, with relaxation of which urine is released. This is how the bladder functions in newborns. In the future, in connection with the maturation of the suprasegmental apparatus, conditioned reflexes are also developed, a sensation of the urge to urinate is formed. Typically, such a urge appears with an increase in intravesical pressure by 5 mm Hg. Art.

An arbitrary component of the act of urination includes control of the external urethral sphincter and auxiliary muscles (abdominal muscles, diaphragm, pelvic diaphragm, etc.).

Sensory neurons are located in the intervertebral nodes S I - S III. Dendrites pass through the pudendal nerve and terminate in receptors both in the bladder wall and in the sphincters. Axons, together with the posterior roots, reach the spinal cord and, as part of the posterior cords, rise to the medulla oblongata. Further, these paths follow to the gyrus fornicatus (sensory area of ​​urination). Through associative fibers, impulses from this zone are transmitted to the central motor neurons located in the cortex of the paracentral lobe (the motor zone of the bladder is located near the zone of the foot). The axons of these cells as part of the pyramidal pathway reach the cells of the anterior horns of the sacral segments (S II - S IV). The fibers of peripheral motor neurons, together with the anterior roots, leave the spinal canal, form the pudendal plexus in the pelvic cavity and, as part of n. pudendus approach the external sphincter. With the contraction of this sphincter, it is possible to voluntarily retain urine in the bladder.

With a bilateral violation of the connections of the cerebral (cortical) zones of the bladder with its spinal centers (this happens with a transverse lesion of the spinal cord at the level of the thoracic and cervical segments), a violation of the function of urination occurs. Such a patient feels neither the urge nor the passage of urine (or catheter) through the urethra and cannot voluntarily control urination. With an acute violation, first comes urinary retention(retentio urinae); the bladder overflows with urine and stretches to a large size (its bottom can reach the navel and above); it can only be emptied with a catheter. In the future, due to an increase in the reflex excitability of the segmental apparatuses of the spinal cord, urinary retention is replaced by periodic incontinence (incontinentio intermittens).

In milder cases, there is an imperative urge to urinate.

In violation of the segmental autonomic innervation of the bladder and sphincters, various urination disorders occur. Urinary retention occurs when the parasympathetic innervation of m. detrusor vesicae of the bladder (segments of the spinal cord S I - S IV, n. pelvicus).

Denervation of the internal and external sphincters leads to true urinary incontinence(incontinentia vera). This occurs when the lumbar segments of the spinal cord and the roots of the cauda equina are affected, n. hypogastricus and n. pudendus. In such cases, the patient cannot retain urine, it is released involuntarily either periodically or continuously.

There is another type of urination disorder - paradoxical urinary incontinence(ischuria paradoxa), when there are elements of urinary retention (the bladder is constantly overfull, it does not empty arbitrarily) and incontinence (urine always flows drop by drop due to mechanical overstretching of the sphincter).

Normal bedwetting (enuresis) in children it occurs before the age of 4 - 5 years and occurs due to the automatic regulation of the function of urination. Enuresis stops when the volume of the bladder is 300-350 ml and accommodates the urine formed during the night. In adults, nocturnal enuresis in the vast majority of cases indicates a functional disease of the nervous system.

The trophic function of nerves is less important for the normal functioning of tissues than blood supply, but at the same time, a violation of innervation can lead to the development of superficial necrosis - neurotrophic ulcers.

A feature of neurotrophic ulcers is a sharp inhibition of reparative processes. This is largely due to the fact that it is difficult to eliminate or at least reduce the influence of the etiological factor (impaired innervation).

Neurotrophic ulcers can form with damage and diseases of the spinal cord (spinal injury, syringomyelia), damage to peripheral nerves.

The main types of necrosis

All of the above diseases lead to the development of necrosis. But the types of necrosis themselves are different, which has a significant impact on the tactics of treatment.

Dry and wet necrosis

It is fundamentally important to separate all necrosis into dry and wet.

Dry (coagulative) necrosis characterized by gradual drying of dead tissues with a decrease in their volume (mummification) and the formation of a clear demarcation line separating dead tissues from normal, viable ones. In this case, the infection does not join, the inflammatory reaction is practically absent. The general reaction of the body is not expressed, there are no signs of intoxication.

Wet (colliquation) necrosis characterized by the development of edema, inflammation, an increase in the volume of the organ, while hyperemia is expressed around the foci of necrotic tissues, there are blisters with a clear or hemorrhagic fluid, the outflow of cloudy exudate from skin defects. There is no clear boundary between the affected and intact tissues: inflammation and edema spread beyond the necrotic tissues for a considerable distance. Characterized by the addition of a purulent infection. With wet necrosis, severe intoxication develops (high fever, chills, tachycardia, shortness of breath, headaches, weakness, profuse sweat, changes in blood tests of an inflammatory and toxic nature), which, when the process progresses, can lead to impaired organ function and death of the patient. The differences between dry and wet necrosis are presented in Table. 13-2.

Thus, dry necrosis proceeds more favorably, is limited to a smaller volume of dead tissues and carries a much lower threat to the patient's life. In what cases does dry necrosis develop, and in which wet necrosis?

Table 13-2. Main differences between dry and wet necrosis

Dry necrosis is usually formed when the blood supply to a small, limited area of ​​\u200b\u200btissues is disturbed, which does not occur immediately, but gradually. More often, dry necrosis develops in patients with reduced nutrition, when there is practically no fatty tissue rich in water. For the occurrence of dry necrosis, it is necessary that pathogenic microorganisms are absent in this zone, so that the patient does not have concomitant diseases that significantly impair immune responses and reparative processes.

Unlike dry necrosis, the development of wet is promoted by:

Acute onset of the process (damage to the main vessel, thrombosis, embolism);

Ischemia of a large volume of tissues (for example, thrombosis of the femoral artery);

Expression in the affected area of ​​tissues rich in fluid (fatty tissue, muscles);

Accession of an infection;

Concomitant diseases (immunodeficiency states, diabetes mellitus, foci of infection in the body, insufficiency of the circulatory system, etc.).

Urination is a reflex act, manifested by the appearance of the urge to defecate. The work of this mechanism is provided by the innervation of the bladder. It is based on the transmission of an impulse along the nerve fibers connecting the sacral spine and the central nervous system, followed by a reduction in detrozur and relaxation of the sphincters of the urethra.

Mechanisms of urinary excretion

Urine excretion occurs by humoral and neuronal regulation. Humoral is carried out due to the secretion of the hormones vasopressin and aldosterone. The reasons for the release of antidiuretic hormone are a decrease in the volume of circulating blood and an increase in the concentration of sodium in it. Aldosterone is produced with a low accumulation of Na ions and a high content of K. Vasopressin is produced in the posterior pituitary gland and has such effects as:

• increased reabsorption of water in the renal tubules;
• a decrease in the level of Na ions and the release of concentrated urine in small volumes;
• an increase in the amount of circulating fluid in the blood and tissues;
• increased tone of smooth muscles.

Aldosterone is produced by the adrenal cortex and affects the formation of urine in the following ways:

• increases the concentration of Na by its reabsorption;
• increases the volume of physiological fluid (NaCl);
• reduces the level of K ions and promotes their excretion in the urine;
• increases muscle tone.

Neuronal regulation is based on the transmission of an impulse from an irritated receptor to the central structures of the brain (paracentral part of the frontal lobe, Barrington's nucleus), spinal cord and vice versa, in order to contract and relax the muscles to empty the bladder. The pathology of the process is manifested by a number of dysuric disorders, in the form of:

• pollakiuria - increased urination;
• stranguria - problems with excretion due to spasm of the urethra neck;
• ischuria - urinary retention;
• - increase in the volume of excreted urine;
• anuria - excretion of no more than 50 ml of fluid per day.

How is the process of innervation of the bladder?

The transmission of the nerve impulse is controlled by the central, peripheral and autonomic nervous system (NS). Each has different anatomical structures management. The autonomic nervous system is a complex of direct voluntary reactions that regulates the process of emptying the urea with the help of sympathetic and parasympathetic fibers.

Sympathetic and parasympathetic NS

The ganglia of the sympathetic part of the autonomic nervous system (ANS) are located away from the organs. They form a chain of nerve fiber bodies, on the side of the ridge in the sacral and lower thoracic (Th12, L1 and L2). The efferent innervation of the sympathetic system is built from preganglionic fibers, paravertebral sympathetic ganglion, postganglionic fibers. The impulse is transmitted through the splanchnic nerves to the inferior mesenteric node. Here the hypogastric plexus picks up the impulse, and leads to smooth muscles. There is a contraction of the internal sphincter and relaxation of the detrusor (the middle layer of the urea wall).

The parasympathetic system is responsible for the motor mechanisms. Nerve fibers are localized in the organ itself or near it. From the sacral centers of the vertebral sections S2, S3 and S4, along the pelvic splanchnic nerves, the impulse reaches the smooth muscle tissue of the bladder. The external sphincter relaxes and the detrusor contracts to allow urination.

Parasympathetic and sympathetic innervation are provided by efferent fibers and are responsible for unconscious urination. Afferent neurons are responsible for the conscious excretion of urine: with an increase in intravesical pressure, receptors are excited and transmit a signal to the spinal cord, then to the cerebral hemispheres on the medial surface with localization in the paracentral lobe.

Violation of the innervation of the bladder

A syndrome that combines a set of symptoms that manifest themselves for congenital or acquired causes. There are three pathological conditions, which are described in the table:

What are the reasons?

• Oncological diseases: prostatic hyperplasia, brain tumor.
• Injuries.
• Diseases of the central nervous system and cardiovascular system.
• Organic disorders in the brain.
• Pathology of the spinal cord.

The urinary process and its connection with the central nervous system is due to the presence of nerves: sympathetic, parasympathetic, spinal. The walls of the organ are equipped with:

• Receptor nerve endings.
• Scattered ANS neurons.
• nerve nodes.

Ensuring the functionality of each of the departments of the urinary system occurs due to the correct exchange of processes through nerve impulses, including. But violations of the function of innervation lead to disorders of a different nature.

innervation- this is the formation of the urge to urinate. Without this mechanism, relaxation of the muscles of the bladder does not occur, or does not occur due to true filling. As a result of the violation, urine is excreted depending on the tension of the muscles, and not on fullness, as it should be in the norm. The causes of this disease can be both age-related changes and infectious diseases. genitourinary system.

Violation of the innervation of the bladder

Innervation of the bladder and urination disorders lead to urinary incontinence, to frequent false urge to urinate, or vice versa - to a delay in emptying. With prolonged urinary retention, urgent hospitalization is required, since, in addition to inflammation and stagnation of urine, this situation is extremely dangerous for the patient's life.

• Hyperreflex. Urine excretion without accumulation process. The clinical picture is frequent urges with a small amount of urine excreted. Etiology as a rule - lesions of the central nervous system;
• Hyporeflex. Difficulty in excretion of urine with its large amount in the bladder. Filling can reach a volume of 0.6 liters. The clinical picture is often associated with frequent inflammatory manifestations of the genitourinary system and kidneys as well. Etiology - disorders of the sacral part of the brain;
• Are reflex. Voluntary uncontrolled urination. The ability to manage the process is completely absent.

Sympathetic innervation of the bladder

The sympathetic innervation consists of fibers that originate from the intermediate column of the lower thoracic and upper lumbar regions, located in the region of the spinal cord. Nerve fibers approach the mesenteric ganglion through the caudal part of the sympathetic trunk and are directed to the smooth muscles of the sphincter. Sympathetic fibers do not have a direct effect on the process of urine excretion. They are concentrated in the neck of the organ. The main role is taken by the ANS cells.

Vegetative innervation of the bladder

ANS cells are directly involved in the process of urination. They are concentrated in the intermediate lateral column of the spinal cord (lumbar). The main function of the fibers is the propulsion system for closing the cervix. As a result of this process, urine is collected. Most often, violations of this particular process provoke the occurrence of a violation.

How to treat a violation of the innervation of the bladder?

Treatment of the disorder depends on the etiology of the disease, as well as on concomitant inflammatory diseases. There are four types of effective conservative treatment:

• electrical stimulation. Sphincter reflexes can be activated by electrical stimulation of the muscles of the groin and anal sphincter. The procedure restores the relationship between the sphincter and the detrusor.
• Medical therapy. Isoptin, Aceclidine or Cytochrome C is prescribed to activate the efferent impulses of the ANS. Preparations based on: coenzymes, calcium ion antagonists, adrenomimetics and cholinomimetics.
• Tranquilizers and antidepressants act in a complex way on the entire nervous system.
• Cholinometric, anticholinergic drugs restore the ability to control the process, stabilize the pressure inside the organ.

In other cases, a decision is made to conduct surgery.

Restoration of innervation of the bladder

Innervation of the bladder with proper and adequate treatment can be restored in full. Treatment differs in duration and method depending on the complexity of the disease, the presence / absence of the inflammatory process, as well as the general clinical picture. Medication or non-medication way to treat is an individual decision of the doctor for each patient. If it is possible to restore function without surgery, medication is chosen. complex treatment. With help folk methods functionality cannot be restored.