Operation of superimposed obstetrical forceps

The operation of superimposing obstetric forceps is related to delivery. Labor-delivering operations are called, with the help of which labor is completed. To the delivery operations through the natural birth canal include: extraction of the fetus with the help of obstetric forceps, by vacuum extraction, extraction of the fetus from the pelvic horses, fruit-destroying operations.

The operation of applying forceps is extremely important in obstetrics. Domestic obstetricians have done extremely much to develop and improve this operation, in particular, indications to it have been developed in detail and the conditions for its implementation have been developed, own versions of the instrument have been created, the immediate and remote outcomes of the operation for mother and child have been studied. Great and responsible is the role of the obstetrician in providing prompt care to women in labor in cases of complicated childbirth. It is especially great in the operation of superimposing obstetric forceps. Therefore, among the few but very important midwifery operations (not counting the lungs), the operation of superimposing obstetric forceps undoubtedly occupies a special place both in the relative frequency of its application in comparison with other obstetric operations and in the beneficent results that this operation can give with timely, skilful and careful application of it.

[1], [2], [3], [4], [5]

Purpose and action of obstetric forceps

In the literature, the following issues are most often discussed:

1. whether obstetric forceps are intended only for the head (including the posterior one), or they can also be applied to the buttocks of the fetus;
2. is it permissible to use forceps to overcome the discrepancy between the size of the pelvis of the mother and the head of the fetus, using force and, in particular, the force of attraction or compression of the head with spoons;
3. what is the nature of the extracting force of the forceps;
4. Whether the rotation of the head is possible with forceps around its vertical or horizontal axis;
5. whether the forceps have a dynamic effect;
6. should the forceps stretch the soft tissues of the birth canal, preparing them for the eruption of the fetal head.

The first question - about the admissibility of applying forceps to the buttocks - in domestic obstetrics was resolved positively. Almost in all manuals it is allowed to put forceps on the buttocks, provided that the latter are already tightly hammered into the entrance of the small pelvis and it is impossible to have a finger for the inguinal fold to extract the fetus. Traction should be carried out carefully because of the ease of slipping forceps.

On the second issue - on the overcoming of mismatch between the head of the fetus and the pelvis of the parturient woman with the help of tongs, a common opinion was formed among the domestic obstetricians. The forceps are not designed to overcome the inconsistency, and the narrow pelvis itself never serves as an indication for the operation. It should be noted that the compression of the head with forceps during the operation is inevitable and represents an inevitable drawback of the instrument. Already in 1901 in the thesis of AL Gel'fer on the corpses of newborns, the change in intracranial pressure was studied when the head was turned by forceps through a narrow basin. The author came to the conclusion that when the head was turned by forceps through the normal pelvis the intracranial pressure was increased by 72-94 mm Hg. Art. Only 1/3 of the cases of pressure increase depends on the compressive action of the forceps, and 1/3 - the compressive action of the pelvic walls. With a true conjugate of 10 cm, intracranial pressure increased to 150 mm, of which 1/3 was due to the use of forceps, with an intracranial pressure of 9 cm, intracranial pressure reached 200 mm, and at 8 cm, even 260 mm Hg. Art.

The most complete substantiation of the view regarding the nature of the extracting force and the possibility of applying a different kind of rotational motion is given by N. N. Fenomenov. At present, there is a clear provision that the forceps are intended only for fetal extraction, and not for artificial change of the head position. In this case, the obstetrician follows the motions of the head and promotes it, combining the forward and rotational movement of the head, as happens in spontaneous childbirth. Dynamic action of forceps is expressed in the strengthened labor activity at introduction of spoons of forceps, however of essential value it has no.

Indication for the imposition of obstetric forceps

Indications for the operation of the application of forceps are usually divided into indications from the side of the mother and from the side of the fetus. In modern guidelines, indications for the operation of superimposing obstetric forceps are as follows: acute distress (suffering) of the fetus and shortening of the II period. There is a significant difference in the frequency of individual indications for surgery. A.V. Lankovits in his monograph "Operation of the imposition of obstetric forceps" (1956) indicates that this difference remains large, even if one does not adhere to the details of the division, and combine the testimony into groups: testimony from the mother, from the fetus and mixed. Thus, the testimony from the mother is from 27.9 to 86.5%, and including mixed, - from 63.5 to 96.6%. Indications from the fetal range from 0 to 68.6%, and including mixed, - from 12.7 to 72.1%. Many authors do not indicate mixed testimony at all. It should be noted that the general statement of testimony given by N. N. Fenomenov (1907) expresses the general that underlies the individual indications and covers the entire variety of particular moments. Thus, NN Phenomenov gave the following general definition of indications for the operation: "The application of forceps is shown in all those cases in which, in the presence of necessary conditions for their use, the expelling forces are insufficient to end the generic act at the moment. And further: "If during the birth there are any circumstances that threaten the danger to the mother or the fetus or both, and if this danger can be eliminated by the speedy termination of labor with forceps, the tongs are shown." Indications for the application of forceps are the threatening condition of the parturient woman and fetus, requiring, as in the operation of fetal extraction, the urgent completion of the birth act.

These are: decompensated heart defects, severe lung and kidney disease, eclampsia, acute infection, accompanied by a rise in body temperature, fetal asphyxia. In addition to these general and for other obstetrical operations, there are special indications for forceps.

1. Weakness of labor. The frequency of this indication is significant. The appearance of signs of compression of the soft tissues of the birth canal or fetus makes it necessary to resort to surgery, regardless of the time during which the head was standing in the birth canal. However, even without obvious signs of compression of the fetal head and soft tissues of the parturient woman, the midwife can resort to an operation on average after 2 hours in the presence of conditions.
2. Narrow pelvis. For an obstetrician in the management of labor, a narrow pelvis is important in itself, but the ratio between the size and shape of the pelvis of the mother and the head of the fetus. It should be mentioned that for a long time the purpose and action of forceps have been seen in the compression of the head, which facilitates holding it through a narrow basin. Subsequently, thanks to the work of domestic authors, especially NN Fenomenova, this view of the action of forceps was abandoned. The author wrote: "Speaking on these grounds in the most categorical manner against the doctrine of a narrow (flat) pelvis, as an indication to forceps, I very well understand, of course, that the application of forceps will nevertheless and should take place with a narrow pelvis, but not for the sake of narrowing, but due to general indications (weakening of labor activity, etc.), in the presence of conditions necessary for forceps. After the nature with the help of an appropriate head configuration has blotted out or almost blurred the original existing discrepancy between the pelvis and the ancestral object, and when the head has already completely or almost completely passed the narrowed place and needs only strengthening (weakened) exertion that can to be replaced artificially, the operation of applying forceps in this case is quite an appropriate tool. Between this look at the pincers and the narrow pelvis and the above, the difference is huge and quite obvious. Thus, in my opinion, the narrow pelvis itself can never be regarded as an indication for the operation of applying forceps. After all, the indication for obstetric operations in general is always the same - it is the impossibility of an arbitrary termination of labor without danger to the mother and the fetus. "
3. The narrowness and obstinacy of the soft tissues of the birth canal and infringement of them - these indications are extremely rare.
4. Unusual insertion of the head. Unusual insertion of the head can not serve as an indication for surgery if it is a manifestation of discrepancy between the pelvis and the head and this discrepancy is not overcome. The tongs should not be used to correct the position of the head.
5. A threatening and complete rupture of the uterus. Currently, only NA Tsovyanov considers the hyperextension of the lower segment of the uterus in the number of indications for the application of forceps. A.V. Lankovits (1956) believes that if the head is in the pelvic cavity, or even more so in its outlet, then in such cases the caesarean section is impracticable, and the spoons of the forceps can not be directly contacted with the uterus, since the neck has already moved past the head . The author believes that in such a situation and the threat of a rupture of the uterus, there are grounds to consider the operation of superimposing cavitary and exit forceps as shown. It is quite obvious that the refusal of vaginal delivery with a diagnosed uterine rupture in childbirth is the doctor's only correct position.
6. Bleeding during delivery only in exceptional cases is an indication for the operation of applying forceps.
7. Eclampsia is an indication for the operation of forceps application quite often, from 2.8 to 46%.
8. Endometritis in childbirth. A. V. Lankowitz, on the basis of observation of 1000 genera complicated by endometritis, believes that only with failure of attempts to accelerate the course of labor with conservative measures or with the appearance of any other serious indications from the mother or fetus is an operation permissible.
9. Diseases of the cardiovascular system - the question should be solved individually, taking into account the clinic of extragenital disease together with the therapist.
10. Diseases of the respiratory system - take into account the functional assessment of the status of the mother in labor with the definition of the function of external respiration.
11. Intrauterine fetal asphyxia. At the appearance of signs of asphyxia, which is not amenable to conservative treatment, immediate delivery is shown.

Conditions necessary for the imposition of obstetric forceps

To perform the operation of applying forceps, a number of conditions are necessary that ensure a favorable outcome for both the parturient and the fetus:

1. Finding the head in the cavity or the outlet of the pelvis. In the presence of this condition, all others, as a rule, are obvious. The operation of applying forceps at a high-standing head refers to so-called high forceps and is not currently applied. However, under high pincers, obstetricians still mean completely different operations. Some under high forceps mean the operation of imposing them on the head, established by a large segment at the entrance to the small pelvis, but not yet passed through the terminal plane, other operations when the head is pressed to the entrance, and the third - when the head is mobile. Under high forceps it means overlapping them when the largest segment of the head, being tightly fixed at the entrance to the small pelvis, did not yet have time to pass through the terminal plane. In addition, quite rightly notes that determining the height of the head in the pelvis is not as simple as it might seem at first glance. None of the proposed methods of determining the height of the head in the pelvis (performing the sacral cavity, the back surface of the womb, the reach of the cape, etc.) can not claim accuracy, since this factor can be influenced by various factors, namely, the size of the head, shape of its configuration, height and deformation of the pelvis and a number of other circumstances that are not always measurable.

Therefore, it is not the head in general that is important, but the largest circumference of it. In this case, the largest circle of the head does not always pass in the same section of the head, but is connected with the insertion singularity. Thus, with the occipital insertion, the largest circumference will pass through a small oblique size, with a parietal (anteroposterior) - through a straight line, with a frontal circumference - through a large oblique and at the front - through a vertical one. However, with all these types of insertion of the head, it is almost correct to assume that the largest circumference of the head passes at the level of the ears. Carrying a high enough half-arm (all fingers, except for the large one) with vaginal examination, you can easily find both the ear and the line of the innominate that forms the border of the entrance to the pelvis. Therefore, it is recommended to perform an investigation before the operation with a semi-hand, and not with two fingers, to reach the ear and accurately determine in which plane of the pelvis the largest circumference of the head is located and how it was inserted.

Below are the variants of the location of the head in relation to the planes of the small pelvis (the Martius scheme), which should be taken into account when applying obstetric forceps:

• option 1 - the head of the fetus above the entrance to the small pelvis, the application of forceps is impossible;
• option 2 - the fetal head with a small segment at the entrance to the small pelvis, the application of forceps is contraindicated;
• option 3 - the fetal head with a large segment at the entrance to the small pelvis, the application of the forceps corresponds to the technique of high forceps. At present, this technique is not used, since other methods of delivery (vacuum extraction of the fetus, caesarean section) give more favorable results for the fetus;
• variant 4 - the head of the fetus in the wide part of the cavity of the small pelvis, cavity forceps may be applied, however, the technique of the operation is very complicated and requires a high qualification of the obstetrician; 
• option 5 - the head of the fetus in the narrow part of the cavity of the small pelvis, can be placed cavity forceps;
• option 6 - the head of the fetus in the plane of exit from the small pelvis, the best position for applying obstetrical forceps using the technique of exit forceps.

A completely secondary role is played by the question of where the lower pole of the head is located, for with a different insertion the lower pole of the head will be located at different heights, with a head configuration the lower pole will be lower. Of great importance is the mobility or immobility of the fetal head. The complete immobility of the head usually occurs only when its largest circle coincides or almost coincides with the plane of entry.

2. Correspondence of the size of the pelvis of the mother and the head of the fetus.
3. The average size of the head, i.e., the fetal head should not be too large or too small.
4. Typical insertion of the head - the forceps are used to extract the fetus, and therefore, they should not be used to change the position of the head.
5. Full disclosure of the uterine throat, when the edges of the pharynx everywhere went beyond the head.
6. A ruptured fetal bladder is an absolutely necessary condition.
7. A living fruit.
8. Exact knowledge of the location of the presenting part, position, including the degree of asynclitism.
9. The lower pole of the head is at the level of the sciatic lobe. It should be noted that a pronounced tumor can mask the true position of the head.
10. Sufficient pelvic outlet dimensions are lin. Intertubero is more than 8 cm.
11. Sufficient episiotomy.
12. Adequate anesthesia (pudendal paracervical, etc.).
13. Emptying the bladder.

Without dwelling on the technique of imposing obstetric forceps, which is covered in all the manuals, it is necessary to dwell on the positive and negative aspects when applying forceps for both the mother and the fetus. At the present time, however, there have been a few studies on the comparative evaluation of the use of obstetric forceps and a vacuum extractor.

[6], [7], [8]

Models of obstetrical forceps

The forceps are an obstetric instrument, by means of which a live, full-term or almost full-term fetus is extracted from the birth canal for the head.

There are over 600 different models of obstetric forceps (French, English, German, Russian). They differ mainly in the structure of the spoons of the forceps and the lock. The levreux tongs (French) have criss-crossed long brunches, a hard lock. The tongs of Negele (German) are short crossed branches, the lock resembles scissors: on the left spoon there is a rod in the form of a cap, on the right there is a notch that approaches the stem. Lazarevich's tongs (Russian) have non-crossed (parallel) spoons with only head curvature and a movable lock.

Recently, most midwives use forceps of the Simpson-Phenomenov model (English): the crossing spoons have two curvatures - the head and pelvic, the lock is semi-mobile, the handle of the forceps has lateral protrusions - Bush's hooks.

General rules for the imposition of obstetric forceps

To perform the operation, the mother is placed on the Rahman bed in the position for vaginal operations. Before the operation, the bladder is catheterized and the external genital organs are treated. The operation of applying obstetrical forceps is performed under general anesthesia or epidural anesthesia. Before surgery, an episiotomy is usually performed.

The main aspects of the operation of applying obstetrical forceps are the introduction of forceps spoons, the closing of the forceps, the performance of tractions (trial and work), the removal of forceps.

The main points of principle that should be observed when applying obstetric forceps are dictated by triple rules.

1. The first triple stain touches the introduction of brunches (spoons) of forceps. They are introduced into the genital tracts separately: the first one is injected with the left spoon into the left side of the pelvis ("three on the left") under the right hand control, the second is inserted the right spoon with the right hand into the right side of the pelvis ("three on the right") under the control of the left hand.
2. The second triple rule is that when closing the forceps, the forceps axis, the axis of the head and the wire axis of the pelvis ("three axes") should coincide. To do this, the forceps should be applied so that the tops of the spoons are facing towards the wire point of the fetal head, grasping the head along the largest circumference, and the wirehead of the head is in the plane of the forceps axis. With the proper application of forceps, the ears of the fetus lie between the spoons of the forceps.
3. The third triple rule shows the direction of traction when removing the head in the forceps, depending on the position of the head ("three positions - three tractions"). In the first position, the fetal head is located in a large segment in the plane of the entrance to the small pelvis, while the traction is directed downwards (on the toes of the sitting obstetrician). The extraction of the fetal head, which is in the entrance to the small pelvis, with the help of obstetric forceps (high forceps) is not currently applied. In the second position, the fetal head is in the pelvic cavity (cavity forceps), while the tractions are performed parallel to the horizontal line (in the direction of the knees of the sitting obstetrician). In the third position, the head is in the exit plane from the small pelvis (output forceps), the tractions are directed from the bottom up (to the face, and at the last moment - to the forehead of the sitting obstetrician).

Technique of imposing obstetric forceps

Output forceps are placed on the head of the fetus, located in the plane of exit from the small pelvis. In this case, the sagittal suture is located in the direct dimension of the exit plane, the forceps are applied in the transverse dimension of this plane.

The introduction of forceps spoons is carried out according to the first triple rule, the closing of the forceps according to the second triple rule. The spoons of forceps are closed only if they lie properly. If the spoons are not in the same plane, then, pressing on the hooks of Bush, the spoons must be turned into one plane and closed. If it is not possible to close the forceps, the spoons should be removed and the forceps applied again. 

After the closure of the spines, tractions are performed. First, to verify the correct application of the forceps I carry out! Trial traction. For this, the right hand grasp the handle of the forceps from above so that the index and middle fingers of the right hand lie on the hooks of Bush. The left hand is placed on top of the right hand so that the index finger touches the head of the fruit. If the forceps are properly applied, then when the test traction is performed, the head moves behind the forceps.

If the forceps are not applied correctly, the index finger is moved away from the fetal head together with the forceps (slipping of the forceps). There are vertical and horizontal slippage. In the case of vertical slippage, the tips of the spoons of the forceps diverge, slide over the head, and exit out of the genital tract. With horizontal slipping, the forceps slide from the head upwards (towards the bosom) or back (to the sacrum). Such slipping is only possible with a high-positioned head. At the first signs of the slipping of the forceps, the operation should be stopped immediately, the spoons of the forceps removed and reinserted.

Working tractions (proper traction) are performed after they are convinced of the success of the trial traction. The right hand remains on the forceps, and the left hand grips the handles of the forceps from below. The direction of traction corresponds to the third triple rule - first on the face, then on the forehead of the sitting obstetrician. The strength of the traction is reminiscent of attempts - gradually increasing and gradually weakening. As well as put out, tractions are performed with pauses, during which it is useful to relax the forceps to avoid excessive squeezing of the head.

After appearing above the crotch of the nape of the fetus, the obstetrician should stand on the side of the parturient woman, grab the handles of the forceps with their hands and direct the traction upwards. After the eruption of the head, the tractions are held upside down with one hand and the other supported by the perineum.

After extracting the largest perimeter of the fetal head, the forceps are removed in the reverse order (first the right spoon, then the left one). After that, the head and shoulders of the fruit are removed by hand. 

The technique of imposing output (typical) obstetric forceps in the back view of the occipital presentation

In the back view of the occipital presentation, the forceps are applied in the same way as in the forward view, but the nature of the traction is different in this case. The first traction is directed steeply down to the pubic symphysis of the region of the large fontanel, then the top is removed by traction.

After appearing above the crotch of the nape of the handle, the forceps are lowered down, the head of the fetus is unbent and a facial part appears in the sexual slit.

The technique of applying cavitary (atypical) obstetric forceps

Hollow forceps are placed on the head of the fetus, located in the cavity of the small pelvis. In this case, the sagittal suture is located in one oblique dimension (right or left) of the pelvis, the forceps are placed in the opposite oblique dimension of this plane. At the first position (the sagittal in the right oblique dimension) the forceps are applied in the left oblique size, at the second position (the sagittal in the left oblique dimension) - in the right oblique dimension (Figure 109).

The introduction of the forceps spoons is carried out according to the first triple rule ("three on the left, three on the right"), but in order for the spoons of the forceps to lie at an oblique size of the pelvis, one of the spoons needs to be shifted upward (to the bosom). The spoon that is not displaced after insertion into the pelvic cavity is called fixed. The spoon, displaced to the bosom, is called wandering. In each individual case, depending on the location of the swept seam, the right one and the left spoon will be fixed. At the first position (a sagittal in the right oblique dimension), the fixed spoon will be left, at the second position (the sagittal in the left oblique dimension) - the right one.

Closing of the forceps, test and working tractions are carried out according to the rules described above.

In addition to complications associated with improper operation techniques, there may be ruptures of the perineum, vagina, large and small labia, and the clitoral region. Possible violations of the act of urination and defecation in the postpartum period.

The operation can be traumatic for the fetus: damage to the soft tissues of the head, cephalohematoma, bleeding in the retina of the eye, impaired cerebral circulation, trauma to the bones of the skull.

The operation of applying obstetrical forceps to the present time remains a sufficiently traumatic method of operative delivery through the natural birth canal. The outcome of labor for the fetus depends largely on the weight of his body, the height of the head, the position of the head, the duration of the operation, the qualification of the doctor, the condition of the fetus at the beginning of the operation, and the quality of neonatal care.

Contraindications to the application of forceps

• stillbirth;
• hydrocephalus;
• facial or frontal insertion;
• incomplete opening of the uterine throat;
• it is not clear the position of the presenting part.

[9], [10], [11]

Complications of the imposition of obstetric forceps

In domestic and foreign literature, attention is drawn to a number of complications in the mother and fetus during the operation of applying obstetric forceps. Particular attention is paid to increasing the number of cephaloids 3-4 times when applying obstetric forceps. In the analysis of 5000 genera, it was revealed that in spontaneous genera of the cephalohematoma it is observed in 1.7% versus 3.5% in the operation of imposing the output obstetric forceps and in 32.7% in the case of cavitary obstetrical forceps. Although no abnormal electroencephalograms or cranial lesions were observed in these observations, 25% of the patients were diagnosed with cephalogomagics, and the authors attributed skull injuries to the use of obstetric forceps. Although the cephalo-damages pass quickly, it should be noted that there are often neonatal complications involving complications of this period of the newborn such as anemia, hyperbilirubinemia, calcification, septicemia and meningitis. Thus, the immediate outcomes of the operation of applying forceps for a child can be considered by dividing all the complications into the following types:

• soft tissue damage;
• cerebral hemorrhage and cranial cavity;
• asphyxia;
• rare damage to the bones of the skull, eyes, nerves, clavicles, etc.

With output obstetrical forceps there was no increase in perinatal morbidity and mortality. With regard to cavity forceps, and up to the present time the question remains unclear. Some authors believe that the decline in perinatal morbidity and mortality is associated with a wider use of caesarean section surgery, and midwifery tongs offer only for difficult births.

In conclusion, it can be rightly said that even Russian-type forceps - the most perfect of all kinds of this instrument - do not constitute a completely safe tool and should not be used without sufficient grounds.

This obstetrics can be the only way to achieve this goal, provided that the obstetrics organization is well organized, creative mastering of the Russian obstetric school heritage, continuous improvement of one's knowledge and experience, and a thoughtful clinical evaluation of the entire organism of the woman giving birth. The difficulties of this path are not small, but they can be overcome.

[12], [13]