PREMATURE PLACENTAL DETACHMENT

From Big Medical Encyclopedia

PREMATURE PLACENTAL DETACHMENT — amotio of normally located placenta during pregnancy or the first two periods of childbirth.

Premature placental detachment on volume can be partial and full. Besides, distinguish premature, spontaneous placental detachment, napr, connected with increase in arterial pressure, and violent, napr, at 'a mechanical injury. Violent amotio meets less than spontaneous.

The etiology and a pathogeny

the Major pathogenetic factor of development of P. of the lake of the item is formation of basal hematomas in a decidua as a result of the increased fragility of its vessels and an adjacent muscular coat of a uterus. Major importance in patol. change of walls of spiral arteries decidua (see) and their increased fragility most often have late toxicoses of pregnant women, and also nephrite, flu, acute respiratory viral infections, vasculites. There is an opinion on an important role of the disseminated intravascular blood coagulation in this pathology. Some researchers attach significance to autoimmunpy processes as to a pathogenetic factor of P. of the lake of the item. Increase in the ABP, a mechanical injury (falling, blow in a stomach), a short umbilical cord, bystry poured out amniotic waters at a hydramnion have incomparably smaller value and hl act. obr. as the allowing factor of emergence of P. of the lake of the item in the presence of late toxicoses of pregnant women. The specified factors at the increased fragility of vessels promote increase in quantity and the sizes of basal hematomas which destroy a basal plate — deep layers of a basal decidua (a basal deciduous cover, T.) also extend in intervillous space. The streaming blood forms a retroplacental hematoma (see. Afterbirth period ) also otslaivat placenta (see) from a wall of a uterus. Along with it there is a diffusion treatment blood of a muscular coat of a uterus, a cut can extend to all its layers up to a peritoneum, appendages of a uterus and in perimetric cellulose.

As a result of P. the lake of the item and treatment by blood of a wall of a uterus in it sharply break exchange processes. The formed products patol, metabolism exert toxic impact on all organism of the woman, and first of all on function of kidneys, a liver, c. N of page and on system of a hemostasis. Expressiveness of metabolic disturbances and the general toxic influence on all organism depends on the volume of treatment by blood of a muscle of a uterus, severity of toxicosis or associated diseases.

The item of the lake of the item causes changes in system of a hemostasis of the woman due to intake of thromboplastic substances and activators of a fibrinolysis from the injured uterus. These changes lead to aggravation of a syndrome of the disseminated intravascular fibrillation and deeper disturbances of system of a hemostasis with development of heavy hemorrhagic diathesis (see. Hemorrhagic diathesis ); besides, it is established that at the same time concentration of fibrinogen and activity I, II, V, VII, VIII, XIII factors decreases, the number of thrombocytes against the background of the normal or a little increased fibrinolitic activity decreases. According to modern data, P. of the lake of the item is preceded by already available disseminated intravascular coagulation in system of uteroplacental blood circulation at heavy late toxicosis of pregnant women (see). The begun P. of the lake of the item promotes transition hron, forms of a syndrome of the disseminated intravascular coagulation in subacute and acute with development of generalized bleeding and heavy hemorrhagic shock (see).

Pathological anatomy

At partial placental detachment during pregnancy on its maternal (uterine) surface after the birth of an afterbirth it is possible to find the impression (a facer or a niche) filled with the organized blood clot. If partial placental detachment occurred at the time of delivery, then impression in a placenta can be absent; on site placental detachments are available dense thin blood clots, almost not speakers on its surface. Recognition of character of P. of the lake of the item in such cases is possible at a section of the placenta which is previously fixed in formalin. At the same time penetration of blood clots into placental fabric and a prelum of the last is found.

Microscopically distinguish two forms P. of the lake of the item: with existence on a placenta of a thin coat of the changed decidua, an otsloyenny hematoma, and with lack of fabric of a decidua, edge it was the otsloyenny blood which got into intervillous space. Changes of fabric of a placenta in sites P. of the lake of the item depend on prescription of amotio and degree of a prelum of placental fabric a hematoma. Usually rapprochement of trailer fibers is found, in places intervillous spaces are overflowed with maternal blood, fresh or changed (with loss of fibrin or gemolizirovanny). Capillaries rezorbtsionny vorsin are sharply expanded.

As a result of damage of the neuromuscular device of a uterus and metabolic frustration motor function of a uterus is sharply broken. In the beginning the uterus is strained, and then becomes flabby — hypotonia and an atony develop. At P. of the lake of the item the uterus can get uniform, sometimes spotty violet coloring, becomes flabby, does not react to mechanical, medicamentous, thermal irritants. Such fortune was come into by the name «Kuveler's uterus», or «an uteroplacental apoplexy». The name is given in honor of the fr. doctor Kuveler, for the first time in 1912 described two similar observations.

The item of the lake of the item exerts negative impact on a fruit. At amotio 1/3 placentae and more he perishes. However death of a fruit can occur also at amotio of smaller sites of a placenta if there are these or those signs of its insufficiency and the more so their combination (the small sizes of a placenta, multiple heart attacks, sites of calcification, disturbance of maturing of a placenta), bringing to its morphological (defects of vascularization), and further and functional inferiority.

Clinical signs

On a wedge, to a current distinguish easy, moderately severe and heavy forms P. of the lake of the item. The easy form practically does not give a wedge, manifestations and is diagnosed upon termination of childbirth during survey of a placenta.

The item of the lake of the moderately severe item is characterized by emergence of the abdominal pains in the beginning localized in the place of the begun amotio, and then poured, which are followed by nausea. The uterus becomes intense, and can be painful at a palpation asymmetric. There are symptoms of pre-natal asphyxia of a fruit (see. Asphyxia of a fruit and newborn , Fruit ). The general condition of the woman worsens, the ABP decreases, there is tachycardia, weakness, skin and visible mucous membranes turn pale. Distribution of blood from a retroplacental hematoma in a lower part of a cavity of the uterus leads to emergence of blood from patrimonial ways. At the same time severity of a condition of the woman does not correspond to rather small size of outside blood loss.

Clinical manifestations of a severe form of P. of the lake of the item depend from patofiziol. changes in an organism, as the lakes of the item previous and arising in the course of P. They develop against the background of the late toxicosis of pregnant women which is combined with idiopathic hypertensia (see), are also followed by simultaneous disturbance of the cerebral circulation bringing to to a coma (see), and an acute renal failure, the cut is a consequence anury (see). In a pathogeny of disturbance of cerebral circulation intravascular blood coagulation and a spasm of peripheral vessels has the leading value. According to modern these P. of the lake of the item, the acute renal failure and disturbance of cerebral circulation represent manifestation of the general patol, process in an organism of the pregnant woman and, in particular, in her vascular system.

At pregnant women with the late toxicosis which is not complicated by somatic pathology, the leading sign of P. of the lake of the item acute massive bleeding in connection with an acute syndrome of the disseminated intravascular blood coagulation and an atony of a uterus is. Placental detachment, as a rule, occurs at the beginning of patrimonial activity, and plentiful uterine bleeding and an incoagulability of blood begin at once after delivery. Clearly signs of disturbance of coagulation, bleeding from the area of a surgery field, hemorrhage to places of injections, petekhialny rash and extravasates on skin and mucous membranes come to light.

The diagnosis and conducting childbirth

In mild cases at survey of an afterbirth on a maternal (uterine) surface of a placenta find the impression filled with a clot. For P. the lake of the moderately severe item characteristic is discrepancy a wedge, manifestations, first of all hemodynamic disturbances (considerable falling of the ABP, tachycardia, etc.), the size of outside bleeding. Recognition of a severe form of P. of the lake of the item is based on data a wedge, options of this pathology. Modern methods ultrasonic diagnosis (see) also allow to establish existence of a retroplacental hematoma. Gistol, a research of a placenta clears up the diagnosis, especially when it is about anti-or intranatal death of a fruit.

At P.'s emergence by the lake of the item it is necessary to remove as soon as possible a fruit from a uterus with the help Cesarean section (see) or to impose obstetric nippers depending on an obstetric situation. At the same time danger of development of hemorrhagic shock with disturbance of hemocoagulation, an acute renal failure and other complications which can arise both after operational, and after spontaneous delivery is considered.

Pre-natal death of a fruit is not a contraindication for Cesarean section if there are no conditions for delivery in the natural way. The question of removal or leaving of a uterus is solved individually. In the presence of irreversible changes of a uterus (Kuveler's uterus) its removal is shown. It is more preferable to make hysterectomy (see) since supravaginal amputation in a similar situation will not provide a reliable hemostasis. The issue is resolved in favor of a hysterectomy and at less expressed morfol, changes if heavy hemorrhagic shock developed. The patient carries out the intensive care directed to completion of volume of the circulating blood, correction of acid-base equilibrium, elimination of water and electrolytic disturbances and recovery of rheological properties of blood. Prevention and treatment of an acute renal failure and other complications are at the same time carried out.

In postoperative period (see) the attention is paid to recovery of reduced body resistance (fight against anemia, use of Thymalinum drugs, mintezol), to prevention of tromboembolic episodes, sepsis and peritonitis.

Forecast

Forecast in mild cases of P. of the lake of the item favorable. At a moderately severe state it depends on timeliness of emptying of a uterus and adequacy of an intensive care. The forecast for mother and a fruit worsens at P. of the lake of the item against the background of heavy toxicosis of pregnant women and the long period from the moment of amotio before emptying of a uterus. Especially adverse forecast at P.o.p., the developed against the background of late toxicosis of pregnant women, somatic pathology, at the begun disseminated intravascular blood coagulation which is followed by an acute renal failure and disturbance of cerebral circulation. The vast majority of such patients perishes.

Prevention

Prevention consists in timely and adequate treatment of late toxicoses of pregnant women and the accompanying somatic pathology, identification and treatment hron, a syndrome of the disseminated intravascular blood coagulation. In case of lack of effect of treatment of late toxicosis is, as a rule, shown to make an early ro-lorazresheniye. Rational maintaining is important childbirth (see) — an exception of rough pressure upon a uterus, slow deflation of amniotic waters at hydramnion (see).



Bibliography: Baksheev N. S. Uterine bleedings in obstetrics, Kiev, 1 975; Bodyazhina V. I. both m and-ý and K. N. Akusherstvo's N, page 376, M., 1979; Zhemkova 3. Item and Topchiyeva O. I. Kliniko-pharmakologichesky diagnosis of insufficiency of a placenta, L., 1973; The Multivolume guide to obstetrics and gynecology, under the editorship of L. S. Persianinov, t, 3, book 2, page 274, M., 1964; Practical obstetrics, under the editorship of. Ya. P. Solsky, page 372, Kiev, 1977; Repina M. A. Some aspects of a pathogeny, clinic and therapy of premature amotio of normally located placenta, Vrpr. protection mat. it is put., t. 22, No. 5, page 55, 1977; The guide to obstetrics and gynecology, under the editorship of L. S. Persianinov, etc., t. 3, book 2, 274, 1964; Beissert M. u. L ö f-ler F. Zur Ätiologie und Häufigkeit. «er vorzeitigen Lösung der normal sitzenden Plazenta, Z. ärztl. Fortbild., Bd 65, 4. 655, L971; Odendaal H. J. Uterine contraction patterns in patients with >to an etega of abruptio placentae, S. Afr. med. J., v. 57, p. 908, 1980; S her G. Trasylol in the management of abruptio placentae th consumption coagulopathy and uterine nertia, J. reprod. Med., v. 25, p. 113,1980.


V. P. Baskakov.

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