The death of a pregnant woman in Xiangtan due to amniotic fluid embolism sparked speculation that \”cesarean section is safer than vaginal delivery.\” Experts interpret –
Be alert to amniotic fluid embolism when a mother suddenly develops dyspnea, cardiogenic shock, convulsions, unexplained fetal distress, or abnormal bleeding.
Medical guidance/Director of Guangzhou Institute of Obstetrics and Gynecology Professor Chen Dunjin Director of Guangzhou Treatment Center for Severe Pregnant Women
Professor Liu Huishu, Department of Obstetrics and Gynecology, Guangzhou Women and Children’s Medical Center
The case of a pregnant woman who died due to amniotic fluid embolism and massive hemorrhage at Xiangtan Maternal and Child Health Hospital spread rapidly in the past two days and attracted widespread attention. There have been various explanations for the obstetric term \”amniotic fluid embolism\”, and many people even believe that natural childbirth is the culprit of amniotic fluid embolism. What exactly is amniotic fluid embolism? Why is amniotic fluid embolism so dangerous? What are the risk factors? What are the signs? Can it be prevented? What if it happens? The reporter interviewed Professor Chen Dunjin, director of the Guangzhou Institute of Obstetrics and Gynecology. Chen Dunjin reminded that the chance of amniotic fluid embolism during caesarean section is 5-6 times that of normal delivery. In addition, if you are pregnant with a boy, the chance of amniotic fluid embolism will also increase.
Text/Reporter Huang Rongfang Correspondents Huang Xianjun, Ye Yuanjuan, Zhou Mi
Dangerous anomalies:
Amniotic fluid embolism has a mortality rate of at least 60%
\”The incidence rate of amniotic fluid embolism is 1/5000~1/20000, of which 70% occur during delivery and 30% occur after delivery. It is currently the third leading cause of maternal death.\” Chen Dunjin said that amniotic fluid embolism is a Postpartum complications occur when amniotic fluid suddenly enters the maternal blood circulation during delivery, causing acute pulmonary embolism, anaphylactic shock, disseminated intravascular coagulation, renal failure or sudden death.
\”This is a rare, sudden, unpredictable and fatal pregnancy complication that may occur in all pregnant women. Once it occurs, it is very dangerous. In the past five years, the incidence rate has increased due to changes in diagnostic standards. \”It has increased. With the advancement of medical technology, the mortality rate has been relatively reduced, but it is at least 60%.\” He said that even if the rescue is successful, 15% of pregnant women will still develop mental or neurological abnormalities. Moreover, the incidence of cerebral palsy in fetuses with amniotic fluid embolism during delivery is more than 20%. Women who have had amniotic fluid embolism are more likely to develop amniotic fluid embolism when they become pregnant again. \”So, it\’s a catastrophic obstetric complication, so to speak.\”
Why is amniotic fluid embolism so dangerous? Chen Dunjin explained that this is mainly because the amniotic fluid enters the maternal blood circulation mainly through the cervical mucosal veins and the venous sinuses where the placenta is attached, which may cause the following four pathophysiological changes: first, anaphylactic shock; second, pulmonary embolism caused by maternal pulmonary hypertension; The first is massive bleeding caused by coagulation disorder; the fourth is lung, heart, kidney and other functional failure. If left untreated, death may result.
Three main reasons:
Premature rupture of membranes, cervical blood vessel rupture, high intrauterine pressure
Normally, fetal amniotic fluid is separated from the mother\’s body by the placental membrane barrier. Why does amniotic fluid \”emboli\” occur? Professor Liu Huishu from the Department of Obstetrics and Gynecology of Guangzhou Women and Children\’s Medical Center said that during delivery, amniotic fluid will break through the barrier between the two and enter the mother\’s blood circulation, causing respiratory failure, circulatory failure, coagulation dysfunction, and even death. As early as 1941 In 2000, formed components of amniotic fluid such as vernix, fetal hair and fetal epithelial cells were found in the lungs of pregnant women who died suddenly, and were believed to be the cause of pulmonary vascular obstruction. With the development of medical technology, new research has also discovered that amniotic fluid embolism actually has a side similar to allergic reactions. The fetus is similar to a semi-allogeneic (half of its genetics comes from the father). When turbid fetal amniotic fluid enters the mother\’s blood circulation, it will cause a reaction similar to anaphylactic shock in the mother. It also contains some procoagulant substances, which will promote changes in the mother\’s coagulation function, causing damage to the mother\’s organ functions in many aspects, and even endangering her life. Therefore, this disease is also called \”pregnancy allergy\”. reaction syndrome”.
What are the causes of amniotic fluid embolism? According to Chen Dunjin, there are mainly the following situations:
One is placental abruption and premature rupture of membranes. Rupture of the fetal membranes will cause amniotic fluid to flow out. Separation of the fetal membranes from the cervical wall will damage blood vessels. Amniotic fluid may enter the maternal blood circulation from the cervical mucosal veins and venous sinuses. Placenta attached. \”If there are strong irregular contractions at the same time, amniotic fluid can easily enter the ruptured blood vessels quickly, causing amniotic fluid embolism.\”
2. Cervical blood vessel rupture. Once the uterine blood vessels rupture, amniotic fluid may flow into the blood vessels, causing amniotic fluid embolism.
Third, intrauterine pressure is high during delivery. This mainly occurs in some women who have had acute labor and multiparous women. Chen Dunjin said that multiparous pregnant women give birth frequently and quickly, and the damage to the birth canal is greater, especially the lower uterine segment and cervical laceration. Once a laceration occurs, vascular channels open and amniotic fluid pressure can easily enter the maternal vasculature. For example, if oxytocin is used incorrectly during labor induction, contractions can be too strong and frequent. They are also more likely to develop amniotic fluid embolism.
High-risk groups:
Cesarean section, boy pregnancy, hypertonic uterus
Regarding the question of whether vaginal delivery is more dangerous and more prone to amniotic fluid embolism than cesarean section, Chen Dunjin emphasized that amniotic fluid embolism may occur in both vaginal delivery and cesarean section, which is unpredictable and difficult to predict. \”In fact, C-sections are more likely to cause amniotic fluid embolism.\”
Chen Dunjin reminded that the following four groups of people are at high risk of amniotic fluid embolism:
The first is a caesarean section. Chen Dunjin said that the incidence of amniotic fluid embolism in cesarean section is 5-6 times that of normal delivery, because there are many more complications in cesarean section than in normal delivery, and the mortality rate of cesarean section is generally higher than that of normal delivery. goods.\”Theoretically, as long as there is a wound during delivery, there is a possibility of amniotic fluid embolism. The wound of cesarean section is obviously much larger than the wound of normal delivery.\” It is actually impossible to suck up the amniotic fluid that flows out instantly.
The second is that she is pregnant with a boy. According to incomplete statistics, most women with amniotic fluid embolism are pregnant with male fetuses. Presumably, it may be because the antigen components of male fetuses are different from those of female fetuses.
Third, the uterine tone is too high. It mainly includes uterine hypertonia caused by macrosomia, twin pregnancy, polyhydramnios, fetal pressure delivery, placenta previa, intrauterine distress, irregular use of oxytocin and other factors.
4. Women who have experienced obstetric complications such as amniotic fluid embolism.
How to prevent:
Amniotic fluid embolism cannot be accurately predicted prenatally
\”Amniotic fluid embolism is unlikely.
Accurate predictions before delivery. \”Chen Dunjin said that since the first paper on amniotic fluid embolism was published in 1924, the pathophysiological mechanism of amniotic fluid embolism is still unclear. \”It is even inconclusive whether to use heparin clinically.\” Therefore, whether amniotic fluid embolism may occur is still unclear. , prenatal examination has little effect. But doctors can pay attention to high-risk groups. Of course, in order to avoid or reduce production risks, oxytocin needs to be used rationally during labor. At the same time, the indications for caesarean section should be strictly controlled and non-medical indications should be avoided as much as possible.
“Although amniotic fluid embolism is difficult to predict, there are still certain signs to follow. \”Chen Dunjin said that amniotic fluid embolism can cause cardiac arrest, unexplained bleeding, hypoxemia and sudden problems that cannot be explained by obstetrics. \”Therefore, when a pregnant woman has sudden dyspnea, cardiogenic shock, convulsions, and is difficult to explain, In cases of fetal distress and abnormal bleeding, obstetricians should always be alert to the possibility of amniotic fluid embolism. \”
\”Most patients will die within 8 minutes to two hours after the onset of symptoms. \”Chen Dunjin believes that once a mother develops amniotic fluid embolism, she should quickly undergo a series of rescue and treatment focusing on ICU advanced life support, which can improve the success rate of treatment. \”This must first form a multi-disciplinary team including obstetrics, respiratory medicine, cardiology and other departments. A medical team composed of experts provides comprehensive treatment. \”
Liu Huishu also believes that sudden and dangerous amniotic fluid embolism is unpredictable, difficult to intervene and uncertain about the treatment effect. \”For the occurrence of amniotic fluid embolism, doctors can only make timely diagnosis and use all resources to actively deal with it, but it is currently impossible to achieve 100% successful treatment. ”