Patient's question:
I get nervous and have a rapid heartbeat when I go to the hospital, over 120 beats per minute. Now I am 23 weeks pregnant with a blood pressure of 140/70.Doctor's answer:
Hello: Pregnancy-induced hypertension syndrome (abbreviated as PIH), also known as gestational hypertension, is a systemic disease unique to pregnant women and occurs primarily after 20 weeks of gestation until 2 weeks postpartum. This condition severely threatens the health of both the mother and fetus and is a leading cause of maternal and perinatal mortality.What are the symptoms of pregnancy-induced hypertension syndrome (PIH)?
(I) Mild PIH
The main symptoms include mild elevation of blood pressure, which may be accompanied by mild edema and trace proteinuria. This stage can last for several days to weeks and may gradually worsen or deteriorate rapidly.
1. Edema: This is the earliest symptom of PIH. Initially, it may only manifest as weight gain (hidden edema), but it gradually progresses to clinically visible edema. Edema typically begins in the ankles and gradually spreads upward. It is classified into four degrees, indicated by "+" signs.
(+) Pitting edema below the knees that does not subside after rest;
(++) Edema extending to the thighs;
(++) Edema extending to the vulva or abdomen;
(+++) Generalized edema, with possible pleural and abdominal effusions.
2. Hypertension: Blood pressure is normal before 20 weeks of gestation but rises to 17.3/12 kPa (130/90 mmHg) or higher after 20 weeks, or increases by 4/2 kPa (30/15 mmHg) compared to baseline blood pressure.
3. Proteinuria: Appears after blood pressure rises, with either no or trace amounts.
(II) Moderate PIH
Blood pressure further increases but does not exceed 21.3/14.7 kPa (160/110 mmHg), with increased proteinuria, edema, and mild symptoms such as dizziness.
(III) Severe PIH
Includes preeclampsia and eclampsia. Blood pressure exceeds 21.3/14.7 kPa (160/110 mmHg), with proteinuria of 10~++ or higher, varying degrees of edema, and symptoms such as headache and blurred vision. Severe cases may develop convulsions and coma.
1. Preeclampsia
In addition to the three main symptoms, symptoms such as dizziness, headache, visual disturbances, upper abdominal discomfort, chest tightness, and nausea/vomiting may appear, indicating further progression of intracranial lesions. At this stage, blood pressure is often above 21.3/14.7 kPa (160/110 mmHg), with more severe edema, decreased urine output, increased proteinuria, and a high risk of convulsions. Active treatment is necessary to prevent eclampsia.
2. Eclampsia
Convulsions may occur on the basis of the above severe symptoms, or accompanied by coma. In some cases, the condition progresses rapidly, with pre-eclampsia symptoms not being prominent, and convulsions occurring suddenly. This typically happens in the late stages of pregnancy or before delivery, though it may occur during delivery or even within 24 hours postpartum in rare cases.
What tests are needed for pregnancy-induced hypertension syndrome (PIH)?
1. Urinalysis: Measure urine specific gravity; ≥1.020 indicates urine concentration, reflecting hypovolemia and blood thickening. Focus on proteinuria; a quantitative value of ≥5.0 g/24 h (>++) indicates a severe condition. Microscopic examination should check for red blood cells and casts, which suggest severe kidney damage.
2. Blood Tests: In facilities with the necessary resources, blood tests should be performed on severe patients, including complete blood count, blood viscosity, hematocrit, serum electrolytes (K+, Na+, Cl-, Ca++), CO2 binding capacity, liver and kidney function, and coagulation function (platelet count, tube coagulation time, fibrinogen, prothrombin time, FDP, etc.).
3. Fundus Examination: Fundus examination serves as a window to assess the degree of systemic small artery spasm and is an important parameter reflecting the severity of PIH. It is crucial for evaluating the condition and determining treatment. All severe patients should undergo routine emergency fundus examinations. Changes such as arteriolar spasm, abnormal arteriovenous ratio, retinal edema, exudation, and bleeding may be observed. Severe cases may develop retinal detachment.
4. Electrocardiogram (ECG): Routine ECG is recommended for severe patients to assess myocardial damage, low or high potassium levels, etc. If necessary, echocardiography should be performed to evaluate cardiac function.
5. Ultrasound Examination: First, to assess fetal development, and second, to evaluate placental function, which is highly valuable for obstetric management of PIH patients. Characteristics of PIH ultrasound include premature placental maturation, aging, and frequent polyhydramnios.
6. Other Tests: Such as cerebral blood flow mapping and CT scans, which may help identify intracranial hemorrhage in severe PIH patients. Fetal movement counting, fetal heart monitoring, fetal maturity assessment, and placental function tests can also help evaluate fetal impact and prognosis.
How is it treated?
Mild PIH can be managed outpatient, while moderate to severe PIH requires hospitalization. Treatment principles include sedation, spasmolysis, antihypertension, volume expansion or diuresis, anticoagulation if necessary, timely termination of pregnancy, and prevention of preeclampsia and severe complications.
(I) General Treatment
1. Left Lateral Recumbency: Rest is crucial for PIH, and left lateral positioning has significant therapeutic benefits.
2. Diet: High-protein, high-vitamin, low-fat, low-carbohydrate, and low-sodium diet.
3. Psychological Support: Alleviate concerns and avoid all adverse stimuli.
(II) Medication
1. Spasmolytics
(1) Magnesium Sulfate: The first-line spasmolytic for moderate to severe PIH.
(2) Anticholinergic Drugs (e.g., 654-2): 10~20 mg IM every 6 hours; 20~50 mg added to 500 ml of 10% glucose for IV infusion, especially suitable for patients with respiratory distress or frequent convulsions.
2. Sedatives
(1) Diazepam: 5~10 mg PO, three times daily; severe cases may receive 10~20 mg IM or IV.
(2) Phenobarbital: Sodium Luminal 100~200 mg IM or Amytal Sodium 0.25 g IM.
(3) Hypnotic Combination: Chlorpromazine 50 mg, Promethazine 50 mg, and Pethidine 100 mg added to 10% glucose for IV infusion. It has advantages such as sedation, antihypertension, reduced metabolism, and improved tolerance to hypoxia, but disadvantages include rapid blood pressure drops, impaired renal and placental blood flow, liver damage, and orthostatic hypotension. It may still be used in cases where magnesium sulfate is contraindicated or ineffective.
3. Antihypertensives
Antihypertensive drugs can lower blood pressure but also reduce blood flow to vital organs, especially the uterus and placenta, posing risks to the fetus. Therefore, they are less commonly used for mild hypertension. For patients with blood pressure still ≥21.3/14.7 kPa (160/110 mmHg) after magnesium sulfate treatment, antihypertensives should be selected to prevent complications such as cerebrovascular accidents and placental abruption, ensuring they do not significantly affect cardiac output, renal function, or uterine/placental blood flow. Blood pressure should not be lowered too rapidly or too low to avoid fetal harm.
(1) Hydralazine: The first-line antihypertensive, which dilates peripheral small blood vessels, reduces peripheral resistance, and lowers blood pressure. It also increases cardiac output, renal blood flow, and uterine/placental blood flow. Dosage: 20~40 mg added to 250-500 ml of 5% glucose for IV infusion. Adjust the infusion rate to maintain diastolic blood pressure above 12 kPa (90 mmHg). Side effects include hypotensive shock, nausea, dizziness, palpitations, and should not be administered IV, nor used rapidly, in large doses, or long-term.
(2) Phentolamine: An α-adrenergic blocker that dilates peripheral blood vessels, renal vessels, and reduces peripheral resistance, especially suitable for patients with heart failure or pulmonary edema. Dosage: 10~20 mg added to 250 ml of 5% glucose for IV infusion.
(3) Reserpine: 0.25 mg PO three times daily or 1-2 mg IM every 6 hours. Side effects include slowed fetal heart rate and newborn nasal congestion. Avoid use 4-6 hours before delivery.
Other drugs such as methyldopa, propranolol, and nifedipine may also be used as needed.
4. Volume Expansion Therapy: The principle is to expand volume after spasmolysis and diurese after volume expansion.
5. Diuretics: Diuretics are generally not recommended but may be used in the following cases: ① PIH complicated by heart failure or pulmonary edema; ② generalized edema or ascites; ③ severe anemia or hypervolemia.
(1) Bumetanide: 25 mg PO three times daily. Take potassium chloride concurrently to prevent hypokalemia.
(2) Triamterene: 50 mg PO three times daily. This drug does not cause potassium loss and does not require potassium supplementation.
(3) Furosemide: Rapid and potent diuretic, used for critically ill patients. Typically 20~40 mg IV; dosage may be increased or repeated as needed. Monitor for hypokalemia, hyponatremia, hypochloremia, and hypovolemic complications.
(4) Mannitol: 20% Mannitol 250 ml infused rapidly within 30 minutes, repeated every 4~6 hours, used for eclampsia with cerebral edema to reduce intracranial pressure.
III. Timely Termination of Pregnancy
PIH is a pregnancy-specific disease, and symptoms improve rapidly after termination. Therefore, timely termination remains the fundamental treatment.
Indications for Termination of Pregnancy:
Severe PIH with active, systematic treatment for 24~72 hours, with unsatisfactory control or worsening of symptoms, should consider termination. If gestational age is ≥36 weeks, the fetus is mature and should also consider termination.