6. Monitoring and symptom identification in prenatal examination

In this article, it is more emphasized to formulate individualized prenatal examination plans to avoid patterned formal prenatal examinations.

In terms of prenatal examination items and frequency, pay attention to individualization and increase the number of prenatal examinations according to the condition to facilitate the control of the changes in the condition. For example, for those diagnosed with preeclampsia, prenatal examinations are required once a week or even twice a week.

In the 2019 ACOG guidelines, it is also emphasized in increasing the number of prenatal examinations.

Among them, unlike other national guidelines, one prenatal examination for this pregnancy has been added to the risk factors of the disease, such as irregular prenatal examination or inappropriate prenatal examination, and factors affecting the diet and environment, which are all risk factors affecting the disease, and these are factors that affect the disease throughout the pregnancy.

It should be emphasized that adverse environment and dietary nutrition factors may continue to have an inducible effect throughout the pregnancy. Pay attention to the investigation of risk factors during any first diagnosis and abnormal conditions, the investigation of early warning information and the analysis of first symptoms should be prevented from focusing only on blood pressure and proteinuria.

Preeclampsia - Eclampsia is a syndrome-based disease. Hypertension with or without proteinuria can be preeclampsia. It is not accompanied by proteinuria but is still diagnosed as preeclampsia with other systems. In the past, hypertension with proteinuria was regarded as a simple preeclampsia.

Recently, it has been noted that pregnancy hypertension without proteinuria is more likely to be manifested as thrombocytopenia and impaired liver function;

For pregnancy hypertension with proteinuria, attention should be paid to distinguish it from renal diseases and autoimmune diseases;

When preeclampsia occurs or clinical manifestations similar to preeclampsia appear before 20 weeks of pregnancy, it is necessary to timely distinguish between autoimmune diseases, TTP, renal diseases, trophoblastic diseases, and hemolytic uremia;

Those who do not relieve postpartum conditions should consider the possibility of hemolytic uremics;

For those with eclampsia and posterior reversible encephalopathy syndrome, they should be distinguished from epilepsy, cerebral artery ischemia or infarction, and intracranial hemorrhage.

Seven, principles for preeclampsia treatment

In the past, the principles of treating hypertensive diseases during pregnancy, especially preeclampsia, emphasized lowering blood pressure, antispasmodic and sedation;

However, in this paper, the basic principles of treatment are summarized as: correctly assess the overall maternal and child condition, rest, sedation, actively reduce blood pressure, prevent convulsions and recurrence of convulsions, indicate diuresis, correct hypoproteinemia, closely monitor maternal and child condition, prevent and promptly treat serious complications, terminate pregnancy in a timely manner, treat underlying diseases, and do a good job in postpartum disposal and management.

8. Clinical application of antihypertensive drugs and magnesium sulfate

1. Antihypertensive drugs:

The blood pressure thresholds for the use of antihypertensive drugs for pregnancy hypertension vary in different countries. There are tips on the use of antihypertensive drugs for mild, moderate hypertension or non-severe hypertension in guidelines in my country and other countries. Most antihypertensive drugs have been used when the blood pressure reaches 150/100mmHg.

When systolic blood pressure is not reached or diastolic blood pressure is ≥160mmHg or diastolic blood pressure is ≥110mmHg, the United States has always recommended not to use antihypertensive drugs. Therefore, there are a series of guidelines for the management of hypertension and antihypertensive treatment in acute severe pregnancy in the United States.

Since the United States does not use antihypertensive drugs for pregnant women with mild or moderate hypertension during pregnancy, and the long-term treatment of pregnant women with hypertension during pregnancy has been intravenous administration as a first-line substance, which is one of the reasons for the change of relevant guidelines in the United States.

There is undoubtedly a sense of urgency to intervene in response to emergencies.

Patients with pregnant hypertension who still emphasize systolic blood pressure ≥140mmHg and diastolic blood pressure ≥90mmHg are recommended for antihypertensive treatment, and emphasize the prevention of severe hypertension. Do not wait until severe hypertension occurs before thinking about dealing with it. Whether it is routine or strict strengthening of blood pressure, maintaining a good pressure control level can reduce the occurrence of severe hypertension and severe preeclampsia.

Also, pay attention to smooth pressure control and avoid excessive pressure reduction, so as not to affect placental perfusion and also to cause fetal growth limitation.

Unlike the United States, there are several clinical situations for acute severe hypertension or persistent severe hypertension in China. For patients who have not used antihypertensive drugs, oral medication can be preferred. Blood pressure is monitored every 10 to 20 minutes. If the blood pressure is still high, the medication will be repeated. After 2 to 3 times, the effect will not be obvious and Immediately use intravenous administration;

For persistent severe hypertension during the use of oral antihypertensive drugs, intravenous antihypertensive methods should be considered. It should be noted that after the blood pressure reduction meets the standards, blood pressure changes are still required. Those with conditions continue to monitor the blood pressure and monitor the blood pressure according to the condition.

2. Magnesium sulfate:

In the past, ACOG did not advocate the use of magnesium sulfate for mild preeclampsia, but was revised in the 2019 guidelines. Although it also raised the trade-offs of risks and benefits, whether to use magnesium sulfate in preeclampsia without serious clinical symptoms should be adjusted by the clinician to make decisions or determine the medical institution.

Although it is a bit vague, it can still be seen that it has changed from "not used" to "available", and it can especially be seen that it is considering the problem step by step from clinical variation.

Such modifications can give clinicians more flexibility. In fact, it emphasizes that magnesium sulfate can be considered for non-severe preeclampsia;

It emphasizes clinical analysis more, abandons the fixed limitation model of only looking at diagnostic standards, advocates a clinical dialectical thinking model that combines the complex conditions of specific patients, and continues to emphasize that magnesium sulfate can also be used as appropriate for patients with non-severe preeclampsia.

In clinical decision-making, it is important to analyze the specific condition. The analysis includes known or unknown courses, conditions, disease development speed, maternal-placenta-fetal involvement, including maternal concealment or known comorbidities, etc. Comprehensive analysis and judgment are the key for clinicians to consider whether to use magnesium sulfate or not. People with stable conditions in non-severe preeclampsia can stop using magnesium sulfate.

Regarding the application of magnesium sulfate in non-severe preeclampsia, the most requires clinical judgment and flexible decision-making.

9. The timing and indications for termination of pregnancy

How to choose the time to terminate pregnancy requires careful clinical analysis and judgment, which is related to pregnancy, condition, and disease classification standards.

For example, there are differences in the diagnosis criteria for severe preeclampsia in different countries. If a single "severe" is used as the only termination of pregnancy, it will not maximize the benefits of mother and child, because there are obvious different conditions within the "severe".

The criteria for severe preeclampsia proposed in the article are different from Canada and the United States. The criteria for severe preeclampsia proposed range from symptomatic manifestations to severe complications, among which those with severe complications must actively terminate their pregnancy, while the severe preeclampsia of certain symptomatic manifestations can be expected to be treated for a period of time.

How to make decisions requires careful individual analysis. "Severe" does not necessarily mean "termination" of pregnancy. "Severe" also means progressing disease to a certain extent, and also means that the mother and child status need to be closely monitored and evaluated, and there is a possibility of termination of pregnancy at any time.

There are several time nodes related to the pregnancy period.

For mild pregnancy hypertension or preeclampsia, it is recommended to expect treatment until the termination of pregnancy by 37 weeks of pregnancy, but rigorous mother-child monitoring and evaluation should be carried out during the expected treatment.

Prenatal examinations can be performed twice a week, pay attention to preeclampsia-related symptoms such as headache, vision changes, upper abdominal pain, etc. Fetal monitoring includes ultrasound examination of fetal growth, and assess amniotic fluid volume at least once a week;

It is recommended to evaluate platelet counts, serum creatinine and liver enzyme levels weekly, and monitor proteinuria weekly for pregnant women with hypertension during pregnancy. Strict clinical monitoring has been paid more and more attention. In the 2019 ACOG Guidelines, these tests should be repeated as soon as possible if the disease progresses.

For severe pregnancy hypertension or severe preeclampsia, if it occurs before 28 weeks of pregnancy, it is necessary to decide whether the expectant treatment can be performed based on the maternal and fetal conditions and the local maternal and child diagnosis and treatment ability;

If it occurs before 34 weeks of pregnancy, the maternal and fetal condition can be considered to expect treatment until 34 weeks of pregnancy termination.

Regarding the expectation of treatment, pregnant women without serious complications should be strictly selected, and the risks and benefits of continuing pregnancy should be evaluated. It is best to expect treatment in a tertiary medical institution. It should have the ability to treat premature babies. It is expected that the mother and fetus should be closely monitored during the treatment period. The progress or worsening of the condition requires the pregnancy to be terminated at any time. The time for termination of pregnancy should not be delayed in order to complete the maturation of the fetal lungs.

In addition to being related to the pregnancy week, the timing of termination is also related to the specific condition of the mother, which requires a detailed and comprehensive analysis of the mother and fetus.

If the mother has serious complications, including severe hypertension uncontrollable, hypertensive encephalopathy and cerebrovascular accidents, PRES, eclampsia, heart failure, pulmonary edema, complete and partial HELLP syndrome, DIC, placental abruption, intrauterine death, etc., pregnancy needs to be terminated in time.

For example, for pregnant women who are pregnant > 34 weeks, if they only have urine protein > 2g/24 hours and do not have other symptoms of severe preeclampsia, they can be closely monitored.

Although urine protein >2g/24 hours is the stage of severe preeclampsia, urine protein >2g/24 hours is not a mere indicator to determine the termination of pregnancy, and it also requires comprehensive analysis.

In this article, not only are the indications of termination of pregnancy related to the gestational week, but also the indications of termination of pregnancy related to the maternal condition are listed.

10. Issues to pay attention to when preventing preeclampsia in small doses

Small dose aspirin used to prevent preeclampsia is currently one of the more certain prevention methods, but there are many problems with how to apply it.

For example, in terms of application objects, the 2013 ACOG Guidelines limited the use of LDA to those with a history of preeclampsia, but by 2019 it has expanded to all populations except those with low-risk groups. In this regard, ACOG also acknowledged that the indications for LDA to prevent preeclampsia are too broad.

FIGO also believes that ACOG defines the indications used by LDA for preventing preeclampsia too broadly.

According to most existing foreign guidelines, it is almost necessary to use LDA to prevent preeclampsia in addition to low-risk pregnant women who have a normal history of full-term pregnancy.

In this regard, some scholars questioned the problem of such a broad application of LDA.

Clinicians are still reminded to pay attention to the selection of application objects and pay attention to multi-faceted prevention, and should not rely on LDA alone. In recent years, there have been too many facts that severe preeclampsia still occurs after the use of LDA and lead to severe adverse outcomes of the mother and child.

Preeclampsia is caused by multiple factors, multiple mechanisms, and multiple pathways. Strategic classification prevention and management according to the different causes, pathogenesis and pathways, which is the key to avoid excessive modeling of medical treatment in various groups.

Emphasizing the role of individual case data in individual heterogeneity analysis is an issue that cannot be ignored.

LDA is used to prevent preeclampsia from preeclampsia, and even if the patient has a high risk of preeclampsia, it may not occur.

The adoption of LDA is only one of the preventive measures. Not overly using LDA is a more important aspect that needs to be considered in clinical practice. Do not rely too much on it is an important clinical thinking method and processing key. Comprehensive and comprehensive analysis and management are required to achieve the purpose of high-quality prenatal care.

11. Screening for preeclampsia

Preeclampsia prediction content has been added, which is one of the existing contents in the national guidelines.

It is suggested that no effective and highly specific preeclampsia prediction method has been established so far, and ultrasound combined with biochemical index detection cannot accurately predict preeclampsia.

Generally speaking, the sensitivity and specificity of biochemical indicators or combined with biophysical parameters for early onset preeclampsia predictions are better than those in late onset preeclampsia, but more research and exploration are needed.

There are roughly two problems with preeclampsia screening. First, the prediction rates of different groups are significantly different, and the positive prediction rate for low-risk pregnant women is only 8% to 33%. However, it is known that half of the preeclampsia occurs in low-risk women without risk factors;

Second, the prediction effects of different types of diseases are different. It is not necessary and beneficial to preventive intervention in a large number of pregnant women who have positive screening but do not develop the disease. There are many other positive patients who have also used LDA to prevent it, but there are also many people who have ended up preeclampsia.

Research in recent years has shown that for the syndrome nature of multi-factor, multi-mechanical, multi-pathogenic preeclampsia, neither suitable for single-mode prevention nor patterned prediction.

The prediction rate for early preeclampsia is lower regardless of whether or not the Doppler ultrasound of uterine artery is combined with other indicators, while the prediction rate for late preeclampsia is even lower.

Clinicians are reminded to note that although a large amount of work has verified that some angiogenic factors play a certain role in the prediction of early preeclampsia in the second trimester, more prospective studies are still needed to confirm their clinical value.

Clinicians are reminded not to rely on a single prevention method or patterned prediction method. They need to pay attention to the screening of maternal risk factors and clinical warning information, and pay more attention to the adverse factors that may occur throughout the pregnancy, and examine the occurrence and development of the disease from multiple perspectives and perspectives.
Chapter completed!