Under normal conditions, during the birth act, the cervix expands under the influence of contractions and the auxiliary role of the fetal bladder. Due to contractions of the uterine muscles, circular fibers of the cervix undergo eccentric stretching, and the fetal bladder in the form of a wedge from above helps to expand the cervical canal.
The situation is different with the artificial expansion of the cervix, it is carried out mechanically, after which the birth ends in one way or another.
Indications for surgery
Indications for mechanical expansion of the cervical canal are: 1) diseases of the mother during pregnancy, requiring urgent interruption of the latter, 2) pathological changes in the cervix that prevent its expansion, 3) all kinds of complications in the period of opening.
Diseases of the mother during pregnancy, requiring urgent interruption of the latter. Diseases that serve as indications for premature termination of pregnancy will in fact also be indications for the expansion of the cervical canal. However, some diseases, by the nature of the course, in addition to terminating the pregnancy itself, also require accelerated expansion of the neck and elimination of everything that accompanies the birth act, namely contractions, enhanced heart function, etc. In these cases, accelerated delivery is indicated, and therefore, fast mechanical neck expansion. Such diseases include kidney diseases, heart defects, eclampsia and some others.
Pathological changes in the cervix
This includes all those diseases of the cervix that prevent its normal expansion under the influence of labor pains.
1. Cervical stiffness . In elderly primiparas, cervical rigidity is sometimes so pronounced that even with good labor, it remains closed. Such a complication can have fatal consequences for the fetus. In view of this, the so-called bloody incision of the cervix is indicated.
Too long the cervix (elongatio uteri) can also be an indication for artificial expansion of the cervical canal. Such a neck, usually swollen, expands with difficulty due to contractions.
2. Cicatricial narrowing of the cervix they are sometimes quite a serious complication, since they are usually not limited only to the neck, but extend deeper and further to the surrounding tissue. Such changes are usually the result of previous difficult births or surgical interventions. With cicatricial changes, the incisions on the cervix are insufficient. In these cases, often coming to raise the question of cesarean section.
3. Vaginofixatio uteri . After this operation, the cervix is turned sharply back, and in addition, between the body of the uterus and the cervix there is no less pronounced kink, which prevents the correct expansion of the cervical canal. In these cases, metreyrisis and sometimes cesarean section may be necessary.
4. Conglutinatio orificii uteri externi - a rare disease with an unknown etiology. It manifests itself in gluing the edges of the external uterus. If they do not lend themselves to the usual method of expansion, you have to resort to a vaginal cesarean section.
Complications in the period of disclosure can occur in cases of convulsive narrowing of the cervix due to certain irritating factors. The opening period under the influence of such a convulsive narrowing of the neck is delayed for a long time. Attempts appear, the head enters the pelvic cavity, and the cervix continues to remain unchanged. Severe cervical rupture can sometimes occur.
With such a convulsive narrowing of the neck, injections of antispasmodics are recommended. If these funds do not lead to the goal, make incisions with scissors.
Sometimes it is necessary to resort to incisions of the external pharynx when removing the fetus beyond the pelvic end. In such cases, a narrow uterine pharynx grasps the fetal neck tightly to free the head and prevent the fetus from dying from asphyxiation; it is recommended that the uterine pharynx be enlarged with a blunt path or scissors.
Bloodless (dumb) ways to expand
Manual (finger) expansion of the uterine pharynx . It is made as follows. After appropriate disinfection of the genitals of the woman in labor and the surgeon’s hands, the doctor inserts the entire arm into the vagina and two fingers into the uterine throat. With these two fingers, as far as possible, push the edges of the uterine throat.
After making sure that the uterine pharynx begins to expand, they try to advance the third finger. After some respite, they begin to expand the pharynx with three fingers, and then enter the fourth. After all five fingers have been inserted into the cervical canal, light helical movements are made with the hand and, turning the hand, they enter it into the uterine cavity.
Manual expansion of the cervical canal can only be started by smoothing the neck and opening the uterine pharynx by at least 2 cm. Anesthesia is recommended.
This method of cervical dilatation has two major drawbacks that make us look for other, more beneficial methods of dilatation.
The first drawback is that the obstetrician’s fingers get tired very soon, cramps appear in the muscles of the hands. If during the expansion to take breaks, the uterine pharynx quickly returns to its original state. The second drawback is that as a result of prolonged finger manipulation, an infection can occur. In view of all this, whenever possible, it is necessary to replace the manual method of expansion with the surgical one.
Delma suggested manual cervical dilation under spinal anesthesia. The significance of spinal anesthesia in this case is twofold: 1) anesthesia and 2) elimination of cervical spasm. With this combined action, according to Delm, the reflex arc connecting the uterus to the nerve centers is interrupted, leaving the sympathetic nervous system intact: uterine contractions and its retraction are not disturbed.
The Delma method can in no way be considered safe (the risk of anesthesia itself, deep ruptures of the neck, subsequent bleeding, infection, etc.), therefore it is not used in the Soviet Union.
Expansion of the cervix using the legs of the fetus . If there is no need to immediately end the birth, with patency of the cervical canal for two transverse fingers make a turn along Braxton-Hicks. By producing the fetal leg with such an early turn, the obstetrician thereby enhances the contractions and, consequently, the opening of the pharynx. This method is not currently applicable. The Braxton-Hicks turn is usually resorted to when placenta previa is used, and the tamponing action of the leg is used (to stop bleeding, and not to expand the neck).
Extension by metal dilators . The most common model of dilators is Geghar metal expanders, slightly curved, 10-12 cm long, of various diameters, equipped with a handle at one end. The number of each individual bougie corresponds to the diameter of its cross section in millimeters.
The expansion is as follows. Having laid the woman in labor on the Rakhmanov bed or on the operating table, the external genitalia are disinfected. After the introduction of the vaginal speculum, the vaginal part and cervical canal are lubricated with iodine tincture and capture the front lip with bullet forceps.
The obstetrician takes the bullet forceps into the left hand and lowers the cervix, and the uterine probe into the right hand, capturing it so that the handle lies between the thumb and index finger of the right hand. With such a clamp, in the event of an obstacle, the probe handle, sliding between the fingers, easily goes back. Violence during the conduct of the probe can lead to the formation of a false stroke and even through penetration of the uterine wall. Only after probing, the cervical canal is expanded with Gegar's bougie.
Fig. 310. Bullet forceps and sharp double-toothed forceps for grasping the cervix.
Fig. 311. Uterine probe.
Without sounding, expansion should not be made. The thinnest metal dilator (2 mm) is the first to be inserted into the cervical canal, moreover, so that its convex side is turned posteriorly and the concave side forward. The dilator should be entered carefully, without violence, holding it so that the pulp of the thumb lies on the handle of the expander in front, from below the handle should lie on a bent index finger. The dilator is introduced beyond the internal uterine pharynx, but no further. The dilator is kept in the cervical canal for several seconds, then removed and replaced with the next number. If the next number is difficult, you must enter the previous number a second time and hold it a little longer. Do not skip over the number due to pain and possible tears. Usually, a pregnant woman can expand the cervical canal to the required size within a few minutes. For curettage of the uterus in the first two months of pregnancy, it is enough to limit the cervical canal to dilatators up to No. 12, inclusive, for the introduction of the metreyrinter - to No. 25-26. Due to soreness, expansion is best done under general anesthesia.
Metreirez consists in the fact that a balloon filled with warm water is injected into the uterine cavity. The balloon, firstly, acts as a foreign body, and secondly, increases intrauterine pressure. Thanks to these two factors, contractions appear that lead to the expansion of the uterus and expulsion (birth) of the balloon. It is recommended that a small weight (400 g) be attached to the cylinder tube.
A device of the type of metrerinter (“tampon expander”) was first proposed by our compatriot D. M. Trubnitsky in 1863. Subsequently, metrerinters of various sizes and shapes were used: pear-shaped, conical, violin-shaped, biscuit-shaped, etc. At one time, Brown's pear-shaped rubber balloons were widely used. However, as a result of the form and material from which the metrerinter is made, it quickly collapses and is thrown out before the pharynx is completely expanded.
М.. M. Sobestiansky made a substantial proposal to connect a burette to the metreyrinter, which, according to the author, helps to establish optimal pressure in the metreyrinter and thereby excludes the possibility of increasing the pressure in it to the extent that threatens its integrity.
N. A. Tsovyanov proposed a very simple and at the same time convenient model of the metrerienter, which the obstetrician himself can do. The Metreyrinter Starovoitova is equipped with a special rubber tube through which, if necessary, a solution of antibiotics can be periodically injected into the uterine cavity. Metrerize for expansion and disclosure of the cervix is recommended for premature termination of pregnancy. Here we would like to say a few words about metreyrisis with placenta previa.
The technique of metreyrisis with placenta previa is as follows. Having disinfected the external genitalia, the woman is placed on the operating table. After the introduction of the mirror, the front and rear lips of the vaginal part are fixed with bullet forceps. The boiled metreyrinter is folded tightly (in the form of a cigar) and seized with special forceps or a forceps, as shown in Fig. 314.
Fig. 312. Probing of the uterus.
Fig. 313. The expansion of the cervical canal with a metal dilator.
Fig. 314. Metreyriz. 1 - metreyrinter, 2 - tongs for gripping the metreyrinter, 3 - syringe for filling the metreyrinter, 4 - folded metreyrinter taken in a clip.
The forceps must grab the balloon so that their ends extend beyond the upper edge of the folded metrerinter. This is done in order to more easily pass through the placenta tissue into the intraaminal cavity. Even before boiling, the integrity of the container should be checked. In the same way, you must first set its capacity. Grabbing the balloon with forceps, inject it through the cervical canal into the uterine cavity, breaking the placenta tissue with forceps. The balloon should not lie between the placenta and the uterine wall, but in the cavity of the fetal egg (intraovularly). To place a balloon between the uterine wall and the placenta (extraovularly) means a large detachment of the placenta and thereby cause dangerous bleeding. Thus, when placenta previa is present, the metrerinter is invariably injected intrashell (intraovularly), having previously opened the fetal bladder, while the same metrerinter, used with simple expansion of the cervical canal, should be administered without first opening the fetal bladder, i.e., extra-enveloped (extraovularly). After the forceps, along with the balloon, pass through the placenta tissue, they (or forceps) are opened without removing them so that the inserted metreyrinter with forceps does not slip out again. Then fill the balloon through a funnel (or syringe) with physiological saline or a 3% solution of boric acid. The metreyrinter is filled with such an amount of liquid, which corresponds to its capacity. Usually this is 150-200 ml.
Fig. 315. The metreyrinter lies intraovularly (intracranial).
Fig. 316. Metreyrinter lies extraovularly (extra-shell).
Filling the balloon, you can carefully remove the tongs or forceps. So that the metreyrinter can fulfill its purpose - to tampon the lower segment of the uterus - it is necessary to hang a load from the tube. Using too much cargo when placenta previa is not recommended, it can do more harm than good. Some adhere to the rule not to suspend a load that would exceed by more than 200 ml the amount of liquid introduced into the cylinder. After the full opening of the uterine pharynx occurs, the balloon goes out on its own. Metreyrinter in the uterine cavity should remain no more than 12 hours.
It is not recommended to pull the metrerinter, which lies in the uterine cavity with placenta praevia, by the tube, after it is expelled, the head should immediately plug the lower segment of the uterus, otherwise bleeding may resume, and then you have to make a turn.
Bloody cervical dilatation
The bloody expansion of the cervix can be an independent operation, in which the cervix that has not been smoothed together with the lower segment is cut so that the fetus can be passed through it. In other cases, cuts or notches are made to the already smoothed neck to remove the obstacle to the acceleration of the birth certificate. In the first case, we are talking about the so-called vaginal cesarean section (hysterotomia vaginal), in the second - obstruction of the uterine pharynx (hysterostomatomatomia).
The conditions necessary for the production of incisions in the external pharynx of the uterus are: a smooth neck and a known opening of the pharynx.
Indications. 1. The section of the uterine pharynx with a smoothed neck (the so-called obstetric pharynx) is shown if, when the fetus is removed from the pelvic end, the pharynx of the uterus tightly grasps the neck. This usually happens if the extraction is undertaken with a not yet fully opened pharynx.
The head usually gets stuck in the uterine cavity. If you pull it very tightly, this can lead to a neck rupture, but if you delay, the fetus may die from asphyxiation. In this case, the incisions of the uterine pharynx are shown.
2. In cases of stricture of the cervix, as well as convulsive narrowing of the uterine pharynx due to various irritations.
3. With stiff neck in elderly primiparas.
4. The notch technique is very simple. Under the control of two fingers, scissors curved along the edge with blunt ends to the uterine pharynx are introduced, with one jaw into the cervical canal, and under the control of the same fingers, a 1 cm incision is made.
Fig. 317. The operation of dissection of the external ("obstetric") pharynx.
Such notches must be made no more than four: two side, one front and one back. Some make a notch in three directions (two notches on the side anteriorly and one on the back).
If it is necessary to apply forceps, it is better for the forceps to be applied earlier: it is more convenient to make incisions on the straining pharynx.
After delivery, it is necessary to stitch the incisions.
The "house" of your puzozhitel is an elongated organ, which consists of muscle and fibrous tissue - the uterus, which ends in the lower part of the neck. As soon as childbirth occurs (researchers, by the way, still cannot find out why childbirth occurs at one time or another), the uterus begins to contract, that is, contractions begin. During contractions (the first period of childbirth - opening), the cervix should fully open and release the fetus. At this time, incredible events take place in the still pregnant body: the uterus, contracting, as it were, “slides” from the ovum, rising up, and the fetus lowers into the cervical canal. Full opening of the neck is fixed when the baby’s head can “crawl” through it. As soon as this happened, the second stage of childbirth begins - expulsion and attempts, which end with the birth of the baby.
In order to be born, the child has to go a very difficult path, but the puzozhitel does not stop at nothing. For example, if the cervix doesn’t let him in, he crawls anyway, and here we get tears that are frequent companions of childbirth. It is easy to guess why this complication arises due to insufficient elasticity of the perineal muscle tissue. Понятное дело, что есть и другие причины разрывов при родах, но тем не менее эластичность матки обязательное условие успешных родов.
Интересно то, что в период беременности матка самостоятельно готовится к предстоящим родам. In the last trimester of pregnancy, muscle tissue is very actively replaced by collagen fibers, which provide it with the ability to stretch. Doctors call this condition "maturity of the uterus and its cervix." Usually, at 39 weeks of gestation, the attending physician determines this “maturity”, in which the length of the cervix should be up to 2 cm, its “consistency” should be soft, the cervical canal should pass one transverse finger over the area of the internal pharynx (this is the result of shortening the cervix) and the cervix should be located in the center of the vagina.
Deviations from these norms (the cervix is too long, its density is tight, the cervical canal is closed and the external pharynx) indicate that the cervix is immature, that is, the body is not ready for childbirth and needs “nourishment”. Doctors call the immature neck "oak." You should not hope that the uterus, ready for childbirth, will provide you with no ruptures, but it is precisely its “maturity” that will greatly reduce their likelihood. Therefore, you should not neglect the preparation.