Hypertensive disorders in pregnancy

Question 1

What is the definition of chronic hypertension in pregnancy?

Answer 1

Chronic hypertension in pregnancy is defined as blood pressure (BP) ≥ 140/90 mm Hg that is present before pregnancy, diagnosed at or before 20 weeks of gestation, or persists beyond 12 weeks postpartum.

Question 2

What is the first step in managing a pregnant woman with chronic hypertension?

Answer 2

The first step is to stop any contraindicated antihypertensive medications, such as diuretics and ACE inhibitors, which can be harmful during pregnancy.

Question 3

What baseline investigations should be conducted in a pregnant woman with chronic hypertension?

Answer 3

Baseline investigations include a Full Blood Count (FBC), Liver Function Tests (LFTs), Creatinine (Cr) and Blood Urea Nitrogen (BUN), and a urine dipstick for protein. A Protein/Creatinine ratio or a 24-hour urine protein collection may be necessary if proteinuria is present.

Question 4

What antihypertensive medications are considered safe for use during pregnancy in women with chronic hypertension?

Answer 4

Safe antihypertensive medications during pregnancy include Methyldopa and Nifedipine as first-line agents. Hydralazine can be used as a second-line agent.

Question 5

What is the target blood pressure range for managing chronic hypertension in pregnancy?

Answer 5

The target blood pressure range for managing chronic hypertension in pregnancy is between 110-140/80-85 mm Hg.

Question 6

How often should fetal well-being be assessed in a pregnant woman with chronic hypertension?

Answer 6

Fetal well-being should be assessed starting from 26 weeks gestation and then at 2-4 weekly intervals if fetal biometry is normal, or more frequently if there is suspected fetal growth restriction. Amniotic fluid index (AFI) should also be measured during each ultrasound exam.

Question 7

How should pregnant women with chronic hypertension be monitored for the development of preeclampsia?

Answer 7

Pregnant women with chronic hypertension should be monitored for preeclampsia by assessing urine dipstick at each visit, conducting clinical assessments, and repeating blood tests (Hb, platelet count, liver transaminases, uric acid, and creatinine) at least at 28 and 34 weeks gestation.

Question 8

What is the definition of gestational hypertension?

Answer 8

Gestational hypertension is defined as new-onset hypertension (BP ≥ 140/90 mm Hg) that occurs after 20 weeks of gestation in a previously normotensive woman, without proteinuria, and resolves by 12 weeks postpartum

Question 9

How is gestational hypertension different from preeclampsia?

Answer 9

Gestational hypertension is characterized by elevated blood pressure without proteinuria or signs of maternal organ dysfunction, whereas preeclampsia includes hypertension along with proteinuria and/or evidence of maternal organ dysfunction.

Question 10

What is the primary goal of managing gestational hypertension?

Answer 10

The primary goal is to control blood pressure to reduce the risk of complications, monitor for the development of preeclampsia, and ensure maternal and fetal well-being.

Question 11

What are the recommended antihypertensive medications for managing gestational hypertension?

Answer 11

Recommended antihypertensive medications for gestational hypertension include Methyldopa and Nifedipine. These are considered safe during pregnancy and help to maintain blood pressure within the target range.

Question 12

What target blood pressure range should be maintained in women with gestational hypertension?

Answer 12

The target blood pressure range should be maintained between 110-140/80-85 mm Hg

Question 13

How frequently should blood pressure be monitored in women with gestational hypertension?

Answer 13

Blood pressure should be monitored regularly, at least weekly or more frequently if there are concerns about control or the development of preeclampsia.

Question 14

What fetal assessments should be conducted in women with gestational hypertension?

Answer 14

Fetal assessments include regular ultrasounds to monitor fetal growth, amniotic fluid volume, and Doppler studies if indicated. Non-Stress Tests (NST) and Biophysical Profiles (BPP) may also be used to assess fetal well-being.

Question 15

What is the recommended management approach if gestational hypertension progresses to preeclampsia?

Answer 15

If gestational hypertension progresses to preeclampsia, the management approach includes more frequent monitoring, possible hospitalization, and planning for delivery depending on the severity of the condition and the gestational age of the fetus.

Question 16

What is the definition of preeclampsia?

Answer 16

Preeclampsia is defined as gestational hypertension accompanied by one or more new-onset conditions after 20 weeks’ gestation, including proteinuria, acute kidney injury, liver involvement, neurological complications, hematological complications, or uteroplacental dysfunction.

Question 17

What are some of the key clinical features used to diagnose preeclampsia?

Answer 17

Key features include hypertension (BP ≥ 140/90 mm Hg), proteinuria, elevated liver enzymes, acute kidney injury (elevated creatinine), neurological symptoms (e.g., severe headaches, visual disturbances), and uteroplacental dysfunction (e.g., IUGR, abnormal umbilical artery Doppler).

Question 18

Is proteinuria mandatory for the diagnosis of preeclampsia?

Answer 18

No, proteinuria is not mandatory for the diagnosis of preeclampsia, though it is present in about 75% of cases. The diagnosis can also be based on other signs of maternal organ dysfunction or uteroplacental dysfunction.

Question 19

What is the management approach for chronic hypertension during pregnancy to prevent the development of preeclampsia?

Answer 19

Management includes stopping contraindicated antihypertensives (e.g., ACE inhibitors), using safe antihypertensives (e.g., methyldopa, nifedipine), maintaining BP between 110-140/80-85 mm Hg, and monitoring for signs of preeclampsia with regular urine dipsticks, clinical assessments, and blood tests at specific intervals.

Question 20

What are the key laboratory tests and fetal assessments recommended for a pregnant woman with chronic hypertension?

Answer 20

Key tests include Full Blood Count (FBC), Liver Function Tests (LFTs), creatinine, and Blood Urea Nitrogen (BUN), along with urine dipstick for protein. Fetal well-being is assessed using ultrasound from 26 weeks gestation, repeated every 2-4 weeks if normal or more frequently if growth restriction is suspected.

Question 21

What is the definition of eclampsia?

Answer 21

Eclampsia is defined as the occurrence of tonic-clonic seizures in a pregnant woman with no previous history of seizure disorders, typically in the context of preeclampsia​

Question 22

What is the initial management approach for eclampsia?

Answer 22

Initial management includes checking circulation, airway, and breathing (CAB), correcting hypoxia with oxygen as needed, protecting the patient from injury (placing in the left lateral position), and admitting to the labor ward (LW) or high-dependency unit (HDU)​

Question 23

How is blood pressure managed in a patient with eclampsia?

Answer 23

Blood pressure is controlled using hydralazine 5 mg IV every 15 minutes, with titration up to 10 mg as needed, until the BP is below 160/110 mmHg. If BP remains uncontrolled after the maximum dose of hydralazine, the patient should be referred to a central hospital​

Question 24

What is the recommended anticonvulsant therapy for eclampsia?

Answer 24

The recommended anticonvulsant therapy is magnesium sulfate (MgSO4) 4 g IV over 10 minutes combined with 5 g IM in each buttock with 1 ml of 2% lignocaine. If seizures recur, an additional 2 g MgSO4 IV is given over 5 minutes. Diazepam may be used if MgSO4 is unavailable​

Question 25

What are the key steps in managing labor and delivery in a woman with eclampsia?

Answer 25

Once seizures are controlled, the delivery process should start within 12 hours. Caesarean section should be considered if vaginal delivery is unlikely within 6-12 hours. Assisted vaginal delivery with vacuum or forceps may be performed if indicated​

Question 26

How is magnesium toxicity managed in eclampsia treatment?

Answer 26

If magnesium toxicity is suspected (e.g., respiratory rate < 16/min, absent knee reflexes), magnesium should be stopped immediately, and 1 g of 10% calcium gluconate IV over 10 minutes should be administered​

Question 27

What is the primary use of magnesium sulfate in the management of preeclampsia?

Answer 27

Magnesium sulfate is primarily used for convulsion prophylaxis in women with preeclampsia to prevent the development of eclampsia​

Question 28

What is the loading dose of magnesium sulfate for preeclampsia management?

Answer 28

The loading dose is 4 g of magnesium sulfate administered intravenously over 10 minutes, followed by 5 g intramuscularly in each buttock​

Question 29

What is the maintenance dose of magnesium sulfate after the loading dose?

Answer 29

After the loading dose, a maintenance dose of 5 g is administered intramuscularly in alternate buttocks every 4 hours for 24 hours

Question 30

What are the signs of magnesium sulfate toxicity?

Answer 30

Signs of magnesium sulfate toxicity include a respiratory rate of less than 10 breaths per minute, oxygen saturation below 92%, muscle paralysis, and absent reflexes

Question 31

How should magnesium sulfate toxicity be managed?

Answer 31

If toxicity is suspected, the infusion should be ceased immediately, and calcium gluconate 10% (10 ml in 100 ml normal saline) should be administered intravenously over 10-20 minutes​

Question 32

What medication is recommended for the prevention of preeclampsia in high-risk patients?

Answer 32

Low-dose aspirin (100-150 mg/day) is recommended, preferably started before 16 weeks of pregnancy for women at increased risk for preeclampsia .

Question 33

What conditions indicate a high risk for preeclampsia and warrant the use of low-dose aspirin?

Answer 33

High-risk conditions include previous preeclampsia, pre-existing medical conditions such as chronic hypertension, underlying renal disease, pre-gestational diabetes mellitus, antiphospholipid antibody syndrome, multiple pregnancy, obesity, and assisted reproduction pregnancy .

Question 34

How does calcium supplementation play a role in the prevention of preeclampsia?

Answer 34

In women with low calcium intake (<600 mg/day), calcium supplementation of 1.2 to 2.5 g per day is recommended to reduce the risk of preeclampsia

Question 35

What is the underlying pathophysiology of preeclampsia?

Answer 35

Preeclampsia is primarily due to abnormal placentation, which leads to insufficient remodeling of the spiral arteries, resulting in reduced placental perfusion and ischemia. This ischemia triggers the release of anti-angiogenic factors, endothelial dysfunction, and systemic inflammation, contributing to the clinical manifestations of preeclampsia

Question 36

What does HELLP syndrome stand for?

Answer 36

HELLP syndrome stands for Hemolysis, Elevated Liver enzymes, and Low Platelet count, and it is a severe form of preeclampsia.

Question 37

What is the primary mechanism behind the hemolysis in HELLP syndrome?

Answer 37

Hemolysis in HELLP syndrome is caused by microangiopathic hemolytic anemia, where red blood cells are damaged as they pass through small blood vessels with endothelial injury and fibrin deposits

Question 38

What leads to low platelet count in HELLP syndrome?

Answer 38

The low platelet count in HELLP syndrome is a result of platelet activation and consumption, secondary to endothelial damage and the formation of microthrombi in the vasculature.

Question 39

How does endothelial dysfunction contribute to HELLP syndrome?

Answer 39

Endothelial dysfunction in HELLP syndrome leads to widespread microvascular injury, which triggers the coagulation cascade, resulting in the consumption of platelets and clotting factors, as well as red blood cell fragmentation.

Question 40

What causes the elevated liver enzymes in HELLP syndrome?

Answer 40

Elevated liver enzymes in HELLP syndrome are due to hepatic injury caused by ischemia, fibrin deposition in hepatic sinusoids, and the formation of hepatic microthrombi, leading to hepatocellular damage

Question 41

What is the primary mechanism of action of magnesium sulfate in the management of eclampsia and preeclampsia?

Answer 41

Magnesium sulfate acts as a central nervous system depressant by blocking neuromuscular transmission and decreasing the release of acetylcholine at the neuromuscular junction, thereby reducing the risk of seizures in eclampsia and preeclampsia.

Question 42

How does magnesium sulfate affect calcium in the body?

Answer 42

Magnesium sulfate competes with calcium at the cellular level, particularly at the N-methyl-D-aspartate (NMDA) receptors, which reduces intracellular calcium levels. This action helps to prevent seizures by stabilizing the excitable membranes of neurons and muscles.

Question 43

What is the effect of magnesium sulfate on blood vessels?

Answer 43

Magnesium sulfate causes vasodilation by directly acting on the vascular smooth muscle and inhibiting calcium-mediated contraction, which can help lower blood pressure and improve blood flow in conditions like preeclampsia.

Question 44

Why is magnesium sulfate considered neuroprotective for the fetus in cases of preterm labor?

Answer 44

Magnesium sulfate is thought to provide neuroprotection by stabilizing the fetal nervous system, reducing the risk of cerebral palsy, particularly in preterm births, through its inhibitory effects on excitatory neurotransmitters and its ability to reduce inflammation and oxidative stress in the fetal brain.

Question 45

How does magnesium sulfate contribute to tocolysis?

Answer 45

Magnesium sulfate inhibits uterine contractions by reducing the intracellular calcium concentration in the uterine muscle, which decreases the contractility of the myometrium, thus acting as a tocolytic agent.

Question 46

What is the mechanism of action of Nifedipine?

Answer 46

Nifedipine is a calcium channel blocker that inhibits the influx of calcium ions through L-type calcium channels in vascular smooth muscle and cardiac muscle. This results in vasodilation, reduced peripheral vascular resistance, and decreased blood pressure, making it effective for managing hypertension, including in pregnancy.

Question 47

How does Methyldopa work to lower blood pressure?

Answer 47

Methyldopa is an alpha-2 adrenergic agonist that is converted in the brain to alpha-methyl norepinephrine. It stimulates central inhibitory alpha-2 receptors, reducing sympathetic outflow and leading to decreased peripheral vascular resistance and blood pressure. It is often used in managing hypertension in pregnancy due to its safety profile.

Question 48

What is the mechanism of action of Hydralazine in managing hypertension

Answer 48

Hydralazine is a direct-acting vasodilator that works by relaxing the smooth muscle in arterioles, leading to decreased peripheral resistance and blood pressure. It primarily acts on the arterioles rather than veins, reducing afterload and making it effective for treating severe hypertension, including hypertensive emergencies in pregnancy.