Uterine atony

Increased weakness of the uterine muscles, which in most cases is the cause of prolonged bleeding that accompanies a woman after childbirth, has its own medical term - uterine atony.

With normal muscle tone, the uterus immediately after the end of obstetric care contracts the spiral capillaries of the placental bed, which helps prevent profuse bleeding from the circulatory system, which penetrates the uterine tissues quite tightly. Muscular contraction of the uterus is also designed to support the relief of this problem. It is mainly this process that helps avoid profuse bleeding from the spiral arteries of the placental bed. Blood clotting in this situation has an indirect effect. If the contractile force of the uterine muscles is impaired, uterine atony is diagnosed.

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Causes of uterine atony

At its core, uterine atony is the loss of the ability of the uterine muscles to contract, which puts this female organ into a state of paralysis. Doctors distinguish between complete and partial absence of uterine tone. It is worth noting that under certain conditions, the pathology in question can lead to the death of the woman in labor.

Medical workers have identified patients who are at risk for developing uterine atony, although there are known cases of severe uterine bleeding in women who were not at risk.

So what categories of women are considered problematic mothers in terms of the risk of postpartum hemorrhage and the probable causes of uterine atony:

• Women who have given birth quite often, as a result of increased stretching of muscle tissue.
• Polyhydramnios in a pregnant woman.
• If an ultrasound examination shows a large fetus.
• Artificial initiation of labor or oxytocin overdose. Excessive administration of uterotonics, drugs intended to induce an artificial abortion or to intensify labor during natural childbirth.
• Hemorrhagic shock.
• A long process of childbirth or, conversely, a rapid resolution of childbirth.
• The cause of uterine atony may be the use of general anesthesia during cesarean section birth. This is especially true for drugs that have a relaxing effect on the muscles of the uterus.
• Congenital pathology of hematopoiesis, for example, thrombocytopenic purpura (hemorrhagic manifestations in the form of hemorrhages under the skin and bleeding).
• If a woman experiences weak labor activity.
• Gestosis or late toxicosis in a woman during pregnancy.
• The administration of magnesium sulfate significantly increases the risk of occurrence and intensification of bleeding.
• An individual feature of a woman's body that manifests itself in a tendency to atony.
• Accumulation of a significant amount of blood clots in the uterine cavity after the passage of the placenta.
• Placenta previa is a pathology characterized by abnormal attachment of the placenta to the walls of the lower parts of the uterus.
• Complicated labor.
• Untimely exit of the placenta from the uterine cavity.
• Trauma to the walls of the uterus during childbirth.
• The woman has post-operative scars.
• A genetically determined defect of the neuromuscular system of the uterus, which manifests itself in immaturity in development, low levels of fetoplacental complex hormones, and decreased ovarian function.
• An inflammatory process that results in pathological changes in the myometrium.
• Benign or malignant tumor.
• Premature detachment of a normally located placenta.
• Violation of homeostasis balance.
• Decreased vascular tone.
• Disruption of the endocrine system balance.
• Embolism is a blockage of the vascular lumen by an embolus, that is, a particle brought in by the blood flow, in this case it could be amniotic fluid.
• Pain shock.

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Symptoms of uterine atony

Uterine bleeding is an integral part of the birth process. Over the next four hours after birth, as doctors have established, the new mother loses on average up to half a liter of this life-giving fluid (quite a strong blood loss). And this is within the norm! Immediately after the baby is born, a heating pad with ice is placed on the woman in labor. It is this cryocompress that helps a healthy woman to quickly contract the blood vessels, which stops further bleeding, and uterine contraction occurs in a shorter period of time.

Over the next few days, the uterus continues to contract until the organ reaches the size corresponding to its parameters before conception. If this is not observed, these are the main symptoms of uterine atony. Severe blood loss, if emergency measures are not taken to stop this pathology, can lead to severe anemia or even death.

A healthy woman physically feels uterine contractions. They are especially clearly felt in the first few days after childbirth. Immediately during feeding, a woman feels a slight heaviness in the lower abdomen, and it is quite natural to observe blood clots coming out of the uterus.

The situation is more complicated when uterine atony leads to hidden internal bleeding. This is especially dangerous if this process remains unnoticed for a long period of time. Such a clinical picture is a precursor to subsequent severe, already external, bleeding. As absurd as it may sound, doctors state that a significantly higher percentage of mortality occurs not in cases of stopping heavy bleeding, but ineffective attempts to stop weak blood discharge.

The main symptoms of uterine atony that should alert the obstetrician who delivers the baby and manages the postpartum period of the woman are:

• Uterine bleeding is inconsistent and of varying intensity.
• The liquid is not released in a homogeneous state, but with denser clots.
• On palpation, the uterus is soft.
• The size parameters of the uterus are increased due to the fact that blood accumulates in it.
• The parameters of the uterus are poorly reduced.
• The level of spontaneous excitability of the uterus decreases.
• Its susceptibility to various stimuli (mechanical, pharmacological, thermal or chemical) is reduced.
• In the nervous apparatus of the uterus, a state is observed that is borderline between the life and death of the cell (the inhibitory phase of parabiosis).
• Visually, one can observe the patient's pallor.
• An increase in heart rate is observed.

The physical and psychological state of a woman largely depends on the intensity of bleeding, hemodynamic stability, the qualifications and experience of the doctor. And most importantly, the timeliness of the medical care provided.

Diagnosis of uterine atony

The main symptom of this disease is bleeding of varying intensity, which begins during or after childbirth. However, it is not worth basing the diagnosis solely on this factor, since the flow of blood from the birth canal may indicate not only bleeding as a symptom of the disease, but also as a natural process included in the obstetric norm. It is simply that during childbirth, blood may accumulate in the uterine space (this is due to individual structural features of this female organ or its dystrophy due to other factors). Liquid volumes can reach up to one liter.

Therefore, to exclude such bleeding, the obstetrician-gynecologist palpates the abdomen to determine the true size of the uterus, since the fluid additionally stretches the walls.

Due to the fact that the volume of circulating blood increases during pregnancy, very often the diagnosis of uterine atony occurs in the postpartum period after serious blood loss. To confirm his guesses, the obstetrician-gynecologist palpates the belly of the woman in labor; with atony, it is soft. The doctor must also at least "by eye" estimate the amount of blood lost. This is done for a period of at least an hour after obstetric assistance. If the health worker suspects uterine atony, the period during which the doctor more closely examines the postpartum symptoms of the woman in labor is extended.

When examining the birth canal with a gynecological speculum, the doctor can observe tissue ruptures affecting the vagina, cervix, and perineum. The reaction of the uterine tissues to pharmacological reactivity and spontaneous excitability is checked. In the case of uterine atony, these manifestations are smoothed out and become less noticeable. The gynecologist also checks the state of the hemocoagulation function - a complex system of interaction of blood proteins, fibrins and platelets, which provides reliable protection of the woman's body from severe high-volume blood loss with minor injuries. Violation of this precarious balance can lead to a decrease in the level of platelets, prothrombin and fibrinogen in the blood of the woman in labor. In this case, an increase in fibrinolytic activity is observed with a decrease in prothrombin time. When examining the blood of a woman with uterine atony, the obstetrician-gynecologist can observe the differentiation of fibrinogen and fibrin breakdown products. Against the background of these changes, the rapid development of DIC syndrome (disseminated intravascular coagulation) is observed, characterized by a violation of the blood coagulation index due to the massive release of thromboplastic substances from tissue cells.

In case of untimely diagnosis of uterine atony and lack of timely adequate treatment, the volume of blood loss increases significantly and can lead to irreversible changes in the body of the woman in labor. With further progression of this pathology, the woman dies from hemorrhagic shock or profuse blood loss.

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Treatment of uterine atony

The tactics of both therapy and prevention of uterine atony are quite similar. Radical measures are difficult to classify as preventive methods during obstetrics.

The main measures taken to stop bleeding can be divided into three types according to their functional focus:

• In order to prevent the development or to quickly stop an already developing disease, the prevention or treatment of uterine atony begins with the invasion of oxytocin, a sufficient concentration of which allows to accelerate the contractile activity of the uterus, preventing the development of atony.

Oxytocin belongs to the pharmacological group of drugs - hormones of the posterior pituitary gland. This drug is mainly prescribed for intramuscular administration. If after this form of administration the therapeutic effect does not occur or is weak, the attending physician in the prescription sheet can change the form of administration to intravenous administration of oxytocin into the body of the woman in labor. In this case, the drug should be administered very slowly, drip (at a rate of 125-165 ml / h). The dosage of the solution is prescribed from 1 to 3 IU, when delivering by cesarean section, oxytocin is primarily injected directly into the uterus in the amount of five IU. If the pathology is quite complex, the dosage can be increased to 5 - 10 IU. This drug is not used in concentrated form, since such an amount of the active substance can lead to arterial hypertension, therefore, only the solution is used in therapeutic therapy.

The drug is strictly contraindicated for administration in case of diagnosis by ultrasound examination, which is usually carried out immediately before the expected birth, of a discrepancy between the size parameters of the mother's pelvis and the size of the baby, as well as an "incorrect" position of the fetus (transverse or oblique). Oxytocin should not be used if there is a real threat of uterine rupture.

Analogues of oxytocin are such medications as clostilbegyt, triderm, hydrocortisone, nasonex, utrogestan, noretin, methylergobrevin, methylergometrine climodiene, ginepristone and others.

The uterotonic drug methergin is administered by a nurse into a muscle or vein, but very slowly, since rapid intravenous administration of the drug can provoke the development of arterial hypertension. This drug is a very powerful drug, the therapeutic effect of which can be observed after a few minutes. The dosage of the drug depends on many factors, including the period of obstetric care.

If the second stage of labor is underway (when the newborn's shoulder appears in the perineum of the mother), methergine is administered intravenously in the amount of 0.1 - 0.2 mg, but not later than the moment when the baby has completely exited. When performing a cesarean section using general anesthesia, the drug is used in the amount of 0.2 mg.

If there is a clinical need for re-treatment, the drug can be re-administered two hours after the first injection.

In case of caesarean section, methergin is taken immediately after the baby is delivered intravenously in the amount of 0.05–0.1 mg or intramuscularly – 0.2 mg.

This drug is prescribed and taken only if the woman is in a hospital under the constant supervision of the attending physician.

It is unacceptable to administer this drug if a woman is just carrying her baby, in the first phase of labor (before the baby's head appears), as well as in the case of nephropathy, sepsis, arterial hypertension, a disease associated with pathological narrowing of peripheral vessels, immediately before the start of breastfeeding the newborn. With great caution should be prescribed for kidney and liver dysfunction and in case of mitral valve stenosis.

• Manipulative techniques are also used to activate uterine contractions and reduce bleeding. In light of these measures, a uterine massage is performed, after which the woman's abdomen is tightly bandaged with a bandage or ligature. Massage is often used as a preparatory stage for other therapeutic measures. Tight bandaging is rarely used in modern medicine.
• In case of suspicion or diagnosis of uterine atony, the doctor resorts to surgical methods to relieve this problem.

A laparotomy (laparotomia mediana) or laparotomy is performed. This procedure is prescribed if the bleeding cannot be stopped by the two previous methods. After opening the peritoneum, the obstetrician-gynecologist ligates the uterine arteries; in particularly severe cases, a situation may arise when the surgeon decides to remove the uterus.

In case of severe bleeding, medical personnel must be prepared to insert a catheter into a large vein and perform volumetric diffusion with previously prepared donor blood (even at the stage of monitoring the pregnant woman at the antenatal clinic, the woman’s blood type is determined without fail, and compatibility tests are performed immediately before childbirth).

The choice of tactics for treating uterine atony is strictly individual and depends on many different indicators, after analyzing which only a qualified specialist can make the right decision, taking into account the plans of the mother for future childbearing.

Prevention of uterine atony

Preventive measures to prevent this pathology are similar to the therapeutic treatment of this disease, but there are still differences. Prevention of uterine atony includes several points:

• The qualifications of the obstetrician-gynecologist who delivers the baby must be sufficient to provide obstetric care at a sufficiently high level: do not press on the abdomen while palpating the uterus. In order not to cause uterine atony, do not pull or tug on the umbilical cord during obstetric care.
• If a woman's health status places her in a risk group for this disease, she is given oxytocin at a certain stage of labor, which allows the uterus to contract more actively, stopping bleeding blood vessels.
• Even before giving birth, during the period of bearing the baby, a qualified hematologist develops a list of sequential actions for the introduction of glucocorticoids (steroid hormones produced by the adrenal cortex) and donor plasma, which comes into effect if the woman in labor begins to bleed heavily.

In order to avoid the need to use uterine atony therapy, especially radical therapy, it is better to prepare the female body for childbirth in advance and carry out preventive measures during the process.

Prognosis of uterine atony

As long as humanity exists, women have had to go through childbirth. Just a hundred years ago, the mortality rate among women in labor was quite high, and only modern medicine has learned to cope with many pathologies that manifest in a pregnant woman during her period of bearing a child or directly during the labor itself. Atony of the uterus is one of the diseases that no woman is immune from. Therefore, only the high professionalism of the medical team attending the birth and the attitude of the woman in labor herself to the birth of her child can make the prognosis of atony of the uterus favorable.

Otherwise, if the woman did not register with the antenatal clinic and did not undergo the necessary examinations (establishing her medical history, blood type and test compatibility) or the obstetrician-gynecologist delivering the baby did not have sufficient experience, the situation could be dire, even fatal for the woman.

A woman - a mother, giving life to a new person in this exciting moment for her, can lose her life. And the reason for such an outcome can be atony of the uterus, manifested due to a combination of certain factors in the postpartum period. What can be advised to expectant mothers in light of this article? First of all, the outcome of the birth of a baby depends on the health, lifestyle and attitude to pregnancy of the expectant young mother herself. If she is initially healthy and followed all the doctor's recommendations during the entire pregnancy, then she should only be advised to decide in advance on the clinic in which she would like her baby to be born. When choosing this specialized medical institution, it is worth inquiring about the level of qualification of its medical staff from those women in labor who have already gone through this path in this maternity ward. If a woman has health problems, it is even more worth taking care of a good clinic and the doctor who will help your baby be born. Thus, the risk of receiving a diagnosis of uterine atony will be significantly reduced. And even if bleeding occurs, an experienced team of doctors will do everything to solve this problem as quickly as possible, while maintaining the health of the baby and his mother!