What Is Abruptio Placentae?

After 20 weeks of pregnancy or during childbirth, the placenta in the normal position is partially or completely stripped from the uterine wall before the fetus is delivered, which is called placental abruption. The main symptoms of mild placental abruption are bleeding from the vagina, the amount of bleeding is generally large, the color is dark red, may be accompanied by mild abdominal pain or abdominal pain is not obvious, the signs of anemia are not significant. The main symptoms of severe placental abruption are sudden and persistent abdominal pain and / or backache, low back pain, the degree of which varies depending on the size of the peeling surface and the amount of blood after the placenta. The more the blood, the more severe the pain.

Basic Information

English name

abruptio placentae

Visiting department

Obstetrics and Gynecology

Multiple groups

Pregnant women after 20 weeks of pregnancy or during childbirth

Common locations

uterus

Common causes

Vascular disease, mechanical factors, sudden increase in uterine venous pressure, smoking, premature rupture of membranes, cocaine abuse, maternal age and parity

Common symptoms

Vaginal bleeding, abdominal pain

Contagious

no

Causes of placental abruption

Vascular disease

Pregnant women with placental abruption are complicated by hypertension and kidney disease during pregnancy, especially those with systemic vascular disease. When the decidua spiral arterioles spasm or sclerosis, the distal capillaries are ischemic and necrotic, resulting in rupture and bleeding. Blood flows to the decidua layer to form a hematoma, which causes the placenta to peel off from the uterine wall.

2. Mechanical factors

Trauma (especially when the abdomen is directly impacted or the abdomen is in direct contact with the ground, etc.), abnormal fetal position, extraversion of the fetus to correct the fetal position, the umbilical cord is too short or the umbilical cord around the neck, and the exposed part of the fetus during the delivery process may all contribute to the early placenta peel. In addition, the first fetus of a twin pregnancy is delivered too fast or the amniotic fluid flows out too fast when the membrane is broken, causing the intrauterine pressure to drop suddenly and the uterus to contract suddenly, which can also cause the placenta to peel off from the uterine wall.

3. Sudden increase in uterine venous pressure

Supine hypotension syndrome can occur when a pregnant woman is in the supine position for a long period of time during or after the third trimester. At this time, due to the huge pregnant uterus compressing the inferior vena cava, the amount of blood returned to the heart is reduced, and the blood pressure is reduced. However, the uterine veins are stasis and the venous pressure is increased, leading to congestion or rupture of the decidual venous bed, causing some or all of the placenta to peel from the uterine wall .

4. Smoking

Studies in the past 10 years have confirmed the relationship between smoking and placental abruption. It has been reported that smoking increases the risk of placental abruption by 90%, and the risk of placental abruption increases with the number of daily smoking. Smoking degenerates blood vessels and increases the fragility of capillaries. The effect of nicotine on vasoconstriction and the increase of carbon monoxide binding protein in serum can lead to vasospasm and ischemia, which can induce placental abruption.

5. Premature rupture of membranes

Many studies at home and abroad have reported the correlation between premature rupture of membranes and placental abruption. The risk of placental abruption in pregnant women with premature rupture of membranes is three times higher than those without premature rupture of membranes. The mechanism of their occurrence is not clear, which may be related to chorioamnionitis after premature rupture of membranes.

6. Cocaine abuse

It has been reported that cocaine was abused during pregnancy in 50 pregnant women, of which 8 stillbirths were caused by placental abruption. It was also reported that 112 cases of pregnant women abused cocaine during pregnancy, resulting in 13% of cases of placental abruption.

7. Maternal age and parity

The age of pregnant women is related to the occurrence of placental abruption, but some scholars have reported that the parity is more related to placental abruption than the age. With the increase of parity, the risk of placental abruption increases geometrically. [1]

Clinical manifestations of placental abruption

1. Light placental abruption

Hemorrhage mainly occurs outside the placenta. The placental surface usually does not exceed 1/3 of the placenta, which is more common during childbirth. The main symptoms are vaginal bleeding, bleeding is generally large, dark red, may be accompanied by mild abdominal pain or abdominal pain is not obvious, anemia signs are not significant. If it occurs during childbirth, the labor process progresses faster. Abdominal examination: soft uterus, intermittent uterine contractions, uterine size consistent with the number of weeks of pregnancy, clear fetal position, normal fetal heart rate, fetal heart rate may change if there is a large amount of bleeding, tenderness is not obvious or only mild local ( Placental abruption) tenderness. Examination of the placenta after delivery showed that there were blood clots and pressure marks on the placenta. Sometimes the symptoms and signs are not obvious. Only when the placenta is examined postpartum, the placenta has clots and indentations on the face, and the placental abruption is found.

2. Heavy placental abruption

Internal bleeding is the main cause, and the placenta is more than 1/3 of the placenta. At the same time, there is a large post-placental hematoma, which is more common in severe PIH. The main symptoms are sudden and persistent abdominal pain and / or backache, low back pain, the degree of which varies depending on the size of the peeling surface and the amount of blood after the placenta. The more the blood, the more severe the pain. In severe cases, nausea, vomiting, and even pale signs, sweating, weak pulses, and decreased blood pressure can be seen. No vaginal bleeding or only a small amount of vaginal bleeding, the degree of anemia does not match the amount of external bleeding. Abdominal examination: Palpate the uterus as hard as a plate, with tenderness, especially at the place where the placenta is attached. If the placenta is attached to the posterior wall of the uterus, the tenderness of the uterus is not obvious. The uterus is larger than the gestational weeks, and with the increase of the post-placental hematoma, the uterine floor will rise and the tenderness will become more obvious. Occasionally contractions, the uterus is in a hypertonic state, can not relax well during the intermittent period, so the fetal position is not clear. If the placenta is more than 1/2 or more of the placenta, the fetus will die due to severe hypoxia, so the fetal heart of most patients has disappeared. [2]

Placental abruption check

1. Type B ultrasound

B-mode ultrasound examination of suspicious and light patients can determine the presence or absence of placental abruption and estimate the size of the peeling surface. If there is a post-placental hematoma, an ultrasound sonogram reveals a dark liquid zone between the placenta and the uterine wall, and the boundaries are less clear. Great for suspicious and light. B ultrasound images of severe patients are more obvious. In addition to the liquid dark area between the placenta and the uterine wall, light spot reflections (hematization) sometimes appear in the dark area, and the placental villous plate protrudes toward the amniotic cavity. And the status of the fetus (with or without fetal movement and fetal heartbeat).

2. Laboratory inspection

Mainly understand the degree of anemia and coagulation function in patients. Blood routine examination to understand the degree of anemia in patients; urine routine to understand renal function and urinary protein. Severe placental abruption may be complicated by DIC, and relevant laboratory tests should be performed, including screening tests for DIC (such as platelet count, thrombinogen time, fibrinogen determination, and 3P test) and fibrinolytic confirmation tests (such as Fi test or FDP immunity Test, thrombin time and euglobulin dissolution time, etc.).

3.Inspection

Placental abruption diagnosis

Diagnosis is mainly based on medical history, clinical symptoms, and characteristics. Because the symptoms and signs of mild placental abruption are not typical, diagnosis is often difficult, and it should be carefully observed and analyzed, and confirmed by B-mode ultrasound. Symptoms and signs of severe placental abruption are typical, and diagnosis is more difficult. At the same time as confirming the diagnosis of severe placental abruption, the severity should be judged. If necessary, the above-mentioned laboratory inspection should be performed to determine whether there are complications such as coagulopathy and renal failure in order to formulate a reasonable treatment plan.

Differential diagnosis of placental abruption

Placenta previa

Mild placental abruption can also be painless vaginal bleeding with no obvious signs. A B-mode ultrasound examination can confirm the lower edge of the placenta to confirm the diagnosis. Placental abruption in the posterior wall of the uterus, abdominal signs are not obvious, and it is not easy to distinguish it from placenta previa. B-ultrasound can also identify. The clinical manifestations of severe placental abruption are very typical, and it is not difficult to distinguish it from placenta previa.

Threatened uterine rupture

It often occurs during childbirth, with strong contractions, refusal to press the lower abdomen, irritability, a small amount of vaginal bleeding, and signs of fetal distress. The above clinical manifestations are difficult to distinguish from severe placental abruption. However, the threatened uterine rupture often has a history of cephalic pelvis, delivery obstruction or cesarean section. Examination can reveal pathological constriction of the uterus, urinary catheterization with gross hematuria, etc., and placental abruption is often a patient with severe PIH. The pattern is hard. [3]

Placental abruption treatment

Correct shock

When the patient is admitted to the hospital in a critical condition and in a state of shock, he should actively replenish blood volume, correct shock, and improve the patient's condition as soon as possible. Blood transfusion must be done in a timely manner, and fresh blood is transfused as much as possible, which can replenish blood volume and coagulation factors.

2. Timely termination of pregnancy

Placental abruption jeopardizes the safety of mothers and children, and the prognosis of mothers and children is closely related to the timely treatment. Before the fetus is delivered, the placenta may continue to detach and it is difficult to control bleeding. The longer the duration, the more serious the condition, and the more likely it is to have complications such as coagulation dysfunction. Therefore, once the diagnosis is confirmed, the pregnancy must be terminated in time. The method of termination of pregnancy depends on the number of parities, the severity of premature ablation, intrauterine status of the fetus, and uterine opening.

(1) Transvaginal childbirth is generally better in women and women. The bleeding is mainly dominant, and the uterine opening has widened. It is estimated that those who can deliver quickly in a short period of time can undergo vaginal delivery. Uterine volume, if necessary, with intravenous infusion of oxytocin to shorten the labor process. During childbirth, closely observe changes in blood pressure, pulse, uterine fundus, contractions, and fetal heart rate.

(2) Caesarean section Heavy placental abruption, especially those who are unable to end childbirth within a short period of time. Although the placental abruption is mild, there are signs of fetal distress and the fetus needs to be rescued. , Maternal illness severe coagulopathy, multiple organ dysfunction. After the fetus and placenta are removed during the operation, intrauterine injection of uterine contractions and massage of the uterus should be performed in time, which can generally make the uterus contract well and control bleeding. If it is found to be a uterine placental stroke, after the active treatment such as injection of uterine contraction and massage, the uterine contraction can be improved and bleeding can be controlled. If the uterus is still not contracted, there is a lot of bleeding and the blood is not condensed, and the bleeding cannot be controlled, then hysterectomy should be performed at the same time as fresh blood is input.

3. Prevent postpartum hemorrhage

Patients with placental abruption are prone to postpartum hemorrhage. Therefore, uterine contractions such as oxytocin and ergometrine should be applied immediately after delivery, and the uterus should be massaged. If the bleeding cannot be controlled by various measures and the uterine contraction is poor, a hysterectomy must be performed in time. If there is a large amount of bleeding without a clot, it should be considered as a coagulation dysfunction and treated as a coagulation dysfunction.

(1) Transfusion of fresh blood Timely and sufficient input of fresh blood is an effective measure to supplement blood volume and coagulation factors. If the stock blood exceeds 4 hours, the platelet function will be damaged and the effect will be poor.

(2) Fibrinogen transfusion If the fibrinogen is low, accompanied by active bleeding, and the blood does not coagulate, the infusion of fibrinogen can be performed intravenously if the effect is poor. Generally, 3 ~ 6g of fibrinogen can be given to get better results.

(3) Transfusion of fresh plasma Fresh frozen plasma is second only to fresh blood. Although it lacks red blood cells, it contains coagulation factors. Generally, 1L of fresh frozen plasma contains 3g of fibrinogen, and can increase the factor and to the lowest effective level.

(4) Heparin is suitable for patients with hypercoagulable stage of DIC and those who cannot directly remove the cause. The treatment of DIC in patients with placental abruption is to terminate the pregnancy to interrupt thromboplastin and continue to enter the blood. For active bleeding in the coagulopathy, heparin application can aggravate bleeding, so heparin treatment is generally not recommended.

(5) Anti-fibrous solvents such as 6-aminocaproic acid can inhibit the activity of the fibrinolytic system. If there is still progressive intravascular coagulation, the use of such drugs can aggravate intravascular coagulation, so it should not be used. If the cause has been removed, DIC is in the stage of hyperfibrinolysis, and it can be used when the bleeding does not stop.

4. Prevention of renal failure

During the process, pay attention to the urine volume at all times. If the urine volume is less than 30mL per hour, the blood volume should be replenished in time. When the urine volume is less than 17mL or no urine, the possibility of renal failure should be considered. 20% mannitol can be used for rapid intravenous injection. Infusion, or bolus intravenous injection, can be reused if necessary, and usually recover within 1 to 2 days. After treatment, the urine output does not increase in the short term, blood urea nitrogen, creatinine, blood potassium, etc. are significantly increased, and the CO ₂ binding capacity is reduced, which indicates that renal failure is serious and uremia occurs. At this time, dialysis therapy should be performed to save the maternal life .

Prognosis of placental abruption

The prognosis of placental abruption is related to the type of placental abruption and whether there is hypertension during pregnancy. Early detection of labor induction and correct treatment are related to prognosis.

Placental abruption prevention

1. Pregnancy hypertension syndrome is prone to occur in the second and third trimester of pregnancy. Once pregnant women have symptoms of hypertension, edema and proteinuria, they should actively go to the hospital for early treatment.

2. Be careful when walking during pregnancy, especially when going up and down the stairs, do not go to crowded places, avoid taking buses, and do not drive, so as not to fall or subject your abdomen to impact and compression.

3. Prenatal examination can detect abnormalities early and deal with polyhydramnios or twin births. Avoid sudden drops in intrauterine pressure. If placental abruption occurs, it can be detected early by ultrasound examination and corresponding countermeasures should be taken as soon as possible.

4. During pregnancy, especially late pregnancy, avoid supine position and abdominal trauma; sudden abdominal pain and vaginal bleeding should be seen immediately. Once the placental abruption is determined, the pregnancy should be terminated promptly, and the labor should be terminated within 6 hours. ^[1-3]