Management of pregnancy and childbirth with a narrow pelvis

The problem of the narrow pelvis remains one of the most urgent and at the same time the most difficult in obstetrics, despite the fact that this issue underwent a certain evolution.

In recent years, due to the preventive direction of domestic medicine, the number of anatomically narrow basins has decreased. At the same time, there are almost no narrow basins with a rough deformation and a sharp narrowing - flat-lobed, kyphotic. Less commonly began to meet obshcheobnomernosuszhennye pelvis, and the degree of narrowing is less. Acceleration and an increase in the ratio of growth to body weight of women contributed to the development of higher capacity cans. Thus, according to modern authors, based on ultrasound and roentgenological methods, it was shown that the average value of the true conjugate at the present time is 12 ± 0.8 cm, and the true conjugate is more than 13 cm in only one in ten women and less than 11 cm - in 6.1%.

At the same time, the absence of grossly deformed pelvises, with the exception of only fractures of the lumbosacral spine and pelvic bones in childbearing age, which are the result of severe trauma from car accidents, should still be said that the problem of the narrow pelvis remains relevant, since New forms of narrow cans appeared in the process of ac- celeration:

• transversely-narrowed;
• Assimilation or long basin according to Kirchhof;
• The pelvis with a reduction in the direct diameter of the wide part of the cavity of the small pelvis.

At the same time, there was a tendency to increase the frequency of these forms of narrow cans.

These pelvis do not have gross anatomical changes, which usually would be easily detected with external and internal studies by tasometer and other methods. Their shape and structure represent different variants of the hips of the flat, masculine, infantile type, since this is due to the rapid growth of modern women, i.e., rapid growth in the length of the female skeleton: the lateral dimensions of the pelvis have decreased, at the same time a narrow, arc, vertically standing iliac bones, the so-called transverse-narrowed pelvis, etc. Therefore, the definition of these forms of a narrow pelvis is currently unthinkable without additional objective methods of examination - the use of ultrasound ovyh research methods, X-ray pelvimetry and others. At the same time there is an increase of birth rate of large fruit, which led to an increase in the frequency of so-called clinically narrow pelvis.

Before proceeding with the assessment of the narrow pelvis, it is necessary to recall the normal biomechanism of labor. It is necessary to take into account the constitution of women. In women of asthenic type, the growth of the body in length with a narrow torso is predominant. The skeleton is narrow and light. The spine often forms a kyphosis in the cervico-thoracic region, as a result of which the body is bent forward. The angle of inclination of the pelvis is 44.8, the lumbar lordosis is 4.3 cm, the mass index is low.

Women of the hypersthenic type are dominated by body dimensions in width. The skeleton is wide and strong. A strengthened physiological lumbar lordosis is noted, as a result of which the body is deflected posteriorly. The angle of inclination of the pelvis is 46.2 °, the lumbar lordosis is 4.7 cm.

With normostenic type of constitution, pregnancy and childbirth proceed normally.

It is necessary to pay attention to the shape of the Michaelis rhombus. Thus, with a flat-braided pelvis, the upper point of the diamond often coincides with the base of the upper triangle. With the oblique pelvis, the lateral points of the rhombus shift accordingly, one higher and the other lower.

Management of labor with a narrow pelvis

The course and management of labor for a narrow pelvis depends not only and not so much on the reduction of its size (excluding the degree of absolute narrowing with a true conjugate of 7-5 cm or less), but rather on the mass of the fetus, more precisely, its head, its adaptability, and also sufficient generic activity. To this should be added the need for maximum preservation of the bladder, because the untimely removal of water entails the above complications and significantly worsens the outcome of labor for both the mother and the fetus. The overwhelming majority of births at the first degree of narrowing of the uniformly flattened and flat pelvis (if we exclude the concomitant possible pathology) ends independently with the birth of a live full-term fetus in 75-85% and even in 90%. However, at present, due to the increased number of large fruits, a relative clinical incompetence may be more likely, requiring a vaginal operative delivery - the imposition of obstetric forceps or a vacuum extractor (preferably an output).

With the purpose of delivery in a number of countries and up to the present time, we are offering and applying tazorasshirating operations - subcutaneous symphysiotomy and pu biotomy, which are not used in our country.

When revealing the absolute inconsistency - delivery by caesarean section. At the II degree of narrowing, independent births are possible, if the head is small, then the pelvis can be functionally sufficient. In these cases, especially, one should not allow the over-stretching and development of the weakness of labor. Keeping childbirth with a common-flat pelvis is an extremely important task for the doctor; their usually heavy, spontaneous delivery is possible in about half the cases.

The doctor, when observing a pregnant woman, must take into account the above-mentioned peculiarities of the narrow pelvis, their functional capabilities in comparison with the fetal weight and in time to be hospitalized in the maternity hospital. To do this, along with the measurement of the pelvis and the weight of the fetus, use also some other signs that characterize the functional possibilities - ultrasound examination, Hofmeyer-Mueller sign with careful application. It is not recommended to apply the Hofmeyer-Muller method using a similar functional test (safer and physiological) in labor, suggesting that the woman in labor give birth 2-3 times, usually with a significant or complete opening of the uterine pharynx during a fight with the doctor's hand inserted into the vagina. The absence of any head movement, or, conversely, a known lowering of the head indicates a different functional capacity of the pelvis.

The second sign - Vasten-Henckel, according to most midwives, is very important, and this should be accepted. It is important to note here that its use is especially valuable when the head is fixed by at least a small segment at the entrance to the pelvis, the water has moved away and there is good generic activity. It should be considered that the sign of Vasten-Genkel is very indicative and his obstetrician can use it repeatedly in the dynamics of the course of childbirth, from the standing of the head to a small segment until it reaches a large segment and does not pass this boundary, narrowing of the pelvis its largest size. Since this sign does not provide convincing guidance for the head above the entrance to the pelvis or at the entrance to the pelvis, it is more appropriate in these cases to speak not about the sign as such, but about whether there is an overhanging head over the bosom or not. However, with some incorrect insertions of the head (high direct stance of the dart-suture-occipital position-with the transversely narrowed pelvis), anterior-parietal declination-with a flat-skeletal pelvis, facial presentation, Vasten's symptom does not give a correct orientation on the relationship between the head and the pelvis. More often it appears to be negative, although the functional balance has not yet been determined.

The obstetrician must remember that the clinical course of labor in the narrow pelvic is longer than usual, and the longer it is, the greater the degree of pelvic narrowing, the more pronounced the clinical mismatch between the head and pelvis during labor. This is due to the necessary time to develop a mechanism inherent in each type of pelvis. It is also necessary to have sufficient generic activity and head configuration. Difficulties in the formation of the head and the mechanism of birth, the duration of these processes lead to fatigue of the parturient woman. Particularly unfavorable in this respect is the flattened flat pelvis with the duration of labor up to 1-2 days, with a posteriorly parietal, less profitable insertion of the head more often produced. With a transversely-tapered pelvis and a high straight stifle suture, which is considered favorable for this pelvic form, the head often passes through the entire pelvis in a straight line.

It should be borne in mind that at the present time, the narrowest pelvis most often meets the transverse-narrowed pelvis with a decrease in the direct size of the wide part of the pelvic cavity. Recall that the wide part of the cavity of the small pelvis is called its part, which is located below the entrance plane, more precisely behind the plane of entry. This section occupies the space bounded from the front by a transverse line dividing the inner surface of the pubic symphysis into two equal parts, at the rear by the line of the joints of the II and III sacral vertebrae, from the sides by the middle of the bottom of the articular acetabulum. The line connecting all the listed entities is a circle corresponding to the plane of the wide part of the small pelvis.

In this plane, the following dimensions are determined:

1. straight - from the upper edge of the III sacral vertebra to the middle of the inner surface of the pubic articulation, in norm it is equal to 13 cm;
2. transverse between the middle points of the acetabulum, it is 12.5 cm;
3. oblique - from the upper edge of the large sciatic notch of one side to the groove of the occlusal muscle of the opposite side, they are equal to 13.5 cm.

Here we should also mention the concept of the plane of a narrow part of the cavity of the small pelvis, which is of great importance for obstetrics. To the narrow part of the cavity of the small pelvis is the space located between the plane of its wide part and the exit plane. It has the following limiting points: in front - the lower edge of the pubic symphysis, behind - the tip of the sacrum; from the sides - the ends of sciatic fossae. The line connecting the above formations is a circle that corresponds to the plane of the narrow part of the small pelvis.

This plane has the following dimensions:

1. straight - from the tip of the sacrum to the lower edge of the pubic symphysis, in norm it is 11.5 cm;
2. transverse - the line connecting the sciatic awns, this size is 10.5 cm.

When a woman in labor is tired, she must be given a medical sleep-rest. We adhere to a dosed sleep-rest after 14-16 hours of the woman's stay in labor, and somatically burdened women with late toxicosis and earlier, if they have fatigue, especially at night and evening. Duration of sleep is dosed from 3-4 to 6 hours, depending on the obstetric situation, in particular the state of the fetal bladder and the duration of the anhydrous interval, as well as the presence or absence of an increase in body temperature in childbirth. It is advisable to use antispasmodics in childbirth.

Often the development of the weakness of labor causes the need for the application of rhodostimulation, which is considered acceptable only if there is no sign of overgrowth of the lower segment of the uterus. When administering labor with the use of rhythm-stimulating agents, it is necessary to pay attention to the background of rhythmostimulation to mild degrees of incompatibility, or when the high-standing Schatz-Unterberger groove is in time to stop the introduction of oxytocic agents. In the second stage of labor, the application of Verbov's bandage is applicable.

With a certain caution in the weakness of labor activity at the first degree of pelvic narrowing and without oxytocic agents, estrogen (on the air) - a glucose-vitamin-calcium background can be applied first followed by 1 / 2-1 h of usual rhythmostimulation (castor oil 30 ml , cleansing enema, quinine by 0.05 g 4 times, up to 6-8 quinine powders can be obtained after 15 minutes). The decision to activate generic activity in maternity females and multifaceted women should be made especially strictly, taking into account the thinning of the lower segment and the threat of its rupture, and only if there is a clear discrepancy between the head and pelvis of the mother.

It is necessary to prevent fetal hypoxia in childbirth. The previously strictly conservative-expectant tactics have now been replaced by a less conservative tactic, in order to avoid damage to the mother's body, to get a live and healthy newborn baby. One of the most gentle methods of delivery is the cesarean section. Especially, this operation is indicated by the combination of an anatomically narrow pelvis with an incorrect insertion of the head, and also with pelvic constriction narrowed in the pelvic outlet cavity (kyphotic and funnel-shaped), with pelvic presentations of the fetus, especially large and in the primiparous elderly, with a scar on the uterus.