What are the specific orders for managing preeclampsia (pre-eclampsia)?

From the Guidelines

Specific orders for preeclampsia include antihypertensive medications, magnesium sulfate for seizure prophylaxis, and delivery planning, with the goal of reducing morbidity, mortality, and improving quality of life. For blood pressure control, labetalol or hydralazine are first-line treatments when systolic BP exceeds 160mmHg or diastolic BP exceeds 110mmHg, as recommended by the ISSHP classification, diagnosis, and management recommendations for international practice 1. Oral options include nifedipine or labetalol.

Key Management Points

• For seizure prevention, magnesium sulfate is administered as a loading dose, followed by a continuous infusion, in women with preeclampsia who have proteinuria and severe hypertension, or hypertension with neurological signs or symptoms 1.
• Strict monitoring, including hourly vital signs, deep tendon reflex checks, and respiratory rate monitoring, is essential.
• Laboratory tests, such as complete blood count, comprehensive metabolic panel, liver function tests, urine protein, and coagulation studies, should be performed every 6-12 hours.
• Fetal monitoring with continuous cardiotocography is necessary.
• Delivery timing depends on gestational age and disease severity, with immediate delivery indicated for severe preeclampsia at ≥34 weeks or for maternal/fetal compromise at any gestational age, as recommended by the ISSHP 1.
• Corticosteroids should be given if delivery is anticipated before 34 weeks to accelerate fetal lung maturity. These interventions are critical as preeclampsia can rapidly progress to eclampsia, HELLP syndrome, or other life-threatening complications.

Antihypertensive Medications

• Labetalol: start with 20mg IV, then 40mg, 80mg, 80mg every 10 minutes as needed, maximum 300mg 1
• Hydralazine: 5-10mg IV every 20-30 minutes 1
• Oral options: nifedipine (10-20mg orally every 4-6 hours) or labetalol (200-800mg orally twice daily) 1

Seizure Prophylaxis

• Magnesium sulfate: 4-6g IV loading dose over 20-30 minutes, followed by 1-2g/hour continuous infusion 1

From the FDA Drug Label

In severe pre-eclampsia or eclampsia, the total initial dose is 10 to 14 g of magnesium sulfate. Intravenously, a dose of 4 to 5 g in 250 mL of 5% Dextrose Injection, USP or 0. 9% Sodium Chloride Injection, USP may be infused. Simultaneously, IM doses of up to 10 g (5 g or 10 mL of the undiluted 50% solution in each buttock) are given Alternatively, the initial IV dose of 4 g may be given by diluting the 50% solution to a 10 or 20% concentration; the diluted fluid (40 mL of a 10% solution or 20 mL of a 20% solution) may then be injected IV over a period of three to four minutes Subsequently, 4 to 5 g (8 to 10 mL of the 50% solution) are injected IM into alternate buttocks every four hours as needed, depending on the continuing presence of the patellar reflex and adequate respiratory function. Alternatively, after the initial IV dose, some clinicians administer 1 to 2 g/hour by constant IV infusion. Therapy should continue until paroxysms cease A serum magnesium level of 6 mg/100 mL is considered optimal for control of seizures. A total daily (24 hr) dose of 30 to 40 g should not be exceeded.

The specific orders for pre-eclampsia are:

• Initial dose: 10 to 14 g of magnesium sulfate
• IV administration: 4 to 5 g in 250 mL of 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP
• IM administration: up to 10 g (5 g or 10 mL of the undiluted 50% solution in each buttock)
• Subsequent doses: 4 to 5 g (8 to 10 mL of the 50% solution) injected IM into alternate buttocks every four hours as needed
• Constant IV infusion: 1 to 2 g/hour
• Therapy duration: until paroxysms cease
• Serum magnesium level: 6 mg/100 mL is considered optimal for control of seizures
• Total daily dose: not to exceed 30 to 40 g 2

From the Research

Treatment Options for Pre-eclampsia

The following are specific orders for pre-eclampsia:

• Oral nifedipine and intravenous labetalol are effective for safely reducing blood pressure to target levels in patients with severe pre-eclampsia 3
• Intravenous hydralazine is a commonly administered arteriolar vasodilator that is effective for hypertensive emergencies associated with pregnancies 4
• Labetalol decreases heart rate and may be preferred because of a lack of reflex tachycardia, hypotension, or increased intracranial pressure 4
• Magnesium sulfate is the drug of choice for the prevention and control of maternal seizures in patients with severe pre-eclampsia or eclampsia during the peripartum period 4

Comparison of Treatment Options

• Nifedipine is the most effective drug to reduce the blood pressure when single dose administration is used, but requires more doses to further reduce the blood pressure 5
• Hydralazine is the most effective when the drug administration is maxed up to three doses within 60 minutes with 20 minutes interval 5
• Intravenous labetalol provides proper reduction of blood pressure in Han Chinese women with pre-eclampsia but has the risk of undesirable maternal and neonatal adverse effects 6
• Magnesium sulfate combined with nifedipine and labetalol has good efficacy in the treatment of pre-eclampsia, promoting the expression of endogenous kallikrein and reducing the level of pregnancy-related hypertension predictors 7

Key Findings

• The time taken to achieve effective blood pressure control was 35 vs. 42 min for oral nifedipine and intravenous labetalol, respectively (P = 0·37) 3
• The effectiveness of the drugs to achieve 20% reduction of mean arterial pressure could be ranked as follows: nifedipine>labetalol>hydralazine (57.49%, 42.13%, and 40.87%, respectively) for single dose 5
• Therapy was more successful in women of the labetalol cohort than those of the nifedipine cohort (107 [93%] vs 112 [82%], P = .0132) 6