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Table 11. Oral antihypertensive therapy. Management of severe preeclampsia
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Table 11
Oral antihypertensive therapy
| Drug | Oral dose by mouth | Assignment scheme |
| Labetalol (Trandate) 100 mg tablets | 100 mg -400 mg | Initially: 100 mg BID Up to: 200–400 mg QID Not to exceed 2. 4 g/day |
| Oxprenolol (Trasicor) 20 mg tablets | 20-160 mg | Initially: 40–80 mg BID Up to: 60–160 mg BID Not to exceed 320 mg |
| Hydralazine (Apresoline) 25 mg tablets | 25–50 mg | Initially: 25 mg BID Up to: 50–100 mg BID Not to exceed 200 mg |
| Nifedipine SR (Coracten SR) capsules 20mg | 20 mg | Initially: 20–30 mg daily Up to: 60–120 mg daily Not to exceed 120 mg |
| Nifedipine (immediate release) | 10–20 mg | Initially: 10–20 mg BID Up to: 40 mg BD Not to exceed 80 mg |
| Clonidine | 75–300 mcg | Initially: 50–150 mcg BID Up to: 150–300 mcg BID Not to exceed 600 mcg |
Fluid managementindicated foroliguria (urine output less than 80 mL/4 hour or less than 500 mL/24 hours). In preeclamptic women, significant renal impairment may occur within 24 hours and therefore observation of urine output over 4 hoursusually recommended. Strict fluid balance monitoring is necessary to avoid pulmonary edema or worsen peripheral edema. The volume of infusion therapy should not exceed 1-2 ml/kg/hour or 85 ml/hour. Maintain a urine output of more than 30 ml/hour (0. 5-1 ml/kg/hour.
As termination of pregnancy is the only cure for preeclampsia/eclampsia the timing and mode of delivery is of the main importance in management of moderate preeclampsia. Studies suggest that the best time of delivery is at 37 weeks of gestation. For women with preeclampsia at ≥ 37+0 weeks’ gestation, immediate delivery is recommended.
If the term is less than 34 weeks, prophylaxis of respiratory distress syndrome (RDS) of a newborn is indicated: 6 mg Dexamethasone every 12 hours (maximum 4 doses), or Betamethasone 12 mg 2 doses IM 12-24 hours apart. Magnesium Sulfate is indicated for neuroprotection, if less than 30 weeks gestation.
Delivery should be initiated with stabilizing of BP and diuresis. The mode of delivery determined by gestational age, cervical score and fetal condition. Conservative management of delivery is appropriative. Cesarean section is reserved for the usual fetal indications. Antihypertensive treatment should be continued throughout labor and delivery to maintain systolic BP at < 160 mmHg and diastolic BP at < 110 mmHg. The third stage of labor should be actively managed with Oxytocin 5 units IV or 10 units IM, particularly in the presence of thrombocytopenia or coagulopathy. Also Syntocinon may be used in the management of third stage. Ergometrine should not be given in any form.
For patient with preeclampsia pain relief is obligatory in labor, epidural anaesthesia is more preferable
Management of severe preeclampsia
Prehospital management
• Oxygen via face mask
• Intravenous access
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• Cardiac monitoring
• Transportation of patient in left lateral decubitus position
• Seizure precautions
In-patient management
Patient with suspicious severe preeclampsia should be urgently hospitalized to intensive care unit (ICU). Main principles and aims of treatment are similar with management of moderate preeclampsia, while the risk of complications is significantly higher. Termination of pregnancy is the only cure for preeclampsia/eclampsia. However, with the exception of cases of acute embryonic compromise, the woman before birth should be stabilized for more successful delivery. The work process is a process of excessive physical, emotional, hormonal, etc. stress for both the mother and the fetus. Intensive antihypertensive therapy should be initiated as fast as possible. (Table 11)
Table 12
Antihypertensive therapy of patient with severe preeclampsia
| Drug | Dose | Route | Comment |
| Labetalol · | Initially 20 mg Repeat with 40–80 mg | IV bolus over 2 minutes | Onset: 5 minutes Repeat: every 10 minutes |
| 20–160 mg/hour | Infusion | Titrate to BP response to a maximum of 300 mg | |
| Nifedipine | 10–20 mg conventional release tablet | Oral | Onset: 30–45 minutes Repeat: after 45 minutes Maximum: 80 mg |
| Hydralazine | 5–10 mg (5 mg if fetal compromise) | IV bolus over 3–10 minutes | Onset: 20 minutes Repeat: every 20 minutes Maximum: 30 mg |
| 10–20 mg/hour | Infusion | Titrate to BP response Refer to Appendix C: Hydralazine protocol | |
| Diazoxide | 15–45 mg | IV rapid bolus | Onset: 3–5 minutes Repeat: after 5 minutes Maximum 150 mg/dose |
Preeclampsia of any severity may be complicated with eclampsia any moment, but the risk and frequency of convulsions is excessively increases in patient with moderate and especially severe preeclampsia. As soon as severe preeclampsia is diagnosed, Magnesium Sulphate must be given to prevent seizures and reduce reflex reactivity. Prophylaxis with Mg Sulfate should be implemented where there are premonitory signs of eclampsia (increased reflexes associated with clonus and/or severe headache, visual changes, abdominal pain, nausea, and vomiting) or following diagnosis of severe pre-eclampsia (diastolic B/P > 110 mmHg, proteinuria > 300mg/24 hours, thrombocytopenia). Mg Sulfate 4 g IV over 20 min is given, followed by a constant IV infusion of about 1 to 3 g/h, with supplemental doses as necessary. Dose is adjusted based on the patient’s reflexes. Patients with abnormally high Mg levels (eg, with Mg levels > 10 mEq/L or a sudden decrease in reflex reactivity), cardiac dysfunction (eg, with dyspnea or chest pain), or hypoventilation after treatment with Mg Sulfate can be treated with Ca gluconate
1 g IV. Alternative drug for prevention and treatment of seizures is Diazepam. For Rapid Control Diazepam 10 - 20 mg would be given IV bolus over 1 - 2 minutes.
As maintenance control Diazepam recommended in dose 5-10 mg/hour (maximum 3mg/kg/24 hours). For this aim Diazepam may be given by infusion syringe pump: 50 mg Diazepam (l0mls) in syringe and start 1 ml/hour to increase 0. 5mls/hour every 15 minutes till maximum 2mls/hour (10 mg/hr).
IV drip infusion may be used:
40 mg (8mls) Diazepam dilute in 500mls 5% Dextrose and start at 10 dpm. Maximum 40dpm (10 mg/hr). Infusion rate is titrated against patient's level of consciousness i. e. to keep her drowsy but arousable.
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Bur the definitive, radical treatment is delivery. The risk of early delivery is balanced against gestational age, severity of preeclampsia, and response to other treatments.
Immediate delivery after maternal stabilization (eg, controlling seizures, beginning to control BP) is indicated for the following:
· Pregnancy of ≥ 37 week
· Eclampsia
· Severe preeclampsia if pregnancy is ≥ 34 week or if fetal lung maturity is documented
· Deteriorating renal, pulmonary, cardiac, or hepatic function
· Acute pulmonary edema
· Persistent neurological symptoms
· Persistent epigastric pain, nausea or vomiting with abnormal liver function tests
· Nonreassuring results of fetal monitoring or testing
· Severe fetal growth restriction
· Placental abruption
· Inability to control hypertension despite adequate antihypertensive therapy
· Deteriorating platelet count.
If delivery can be delayed in pregnancies of about 32 to 34 week, corticosteroids are given for 48 h to accelerate fetal lung maturity.
• In case of severe PE beyond the 34th gestational age, the interruption of pregnancy is indicated.
• In case of severe PE within the first 24 gestational age, the performing of a medical interruption of pregnancy must be clearly discussed with the parents.
• Indications to interrupt the pregnancy in severe cases of PE between 24 and 34 weeks can be either maternal or fetal.
• The woman's condition will always take priority over the fetal condition.
The Mode of birth/delivery:
• will depend on maternal and fetal factors (gestation, presentation)
• will require multidisciplinary consultation
If induction of labor is indicated, an Oxytocin (or Syntocinon®) infusion must be delivered in a concentrated dose via a syringe driver pump.
The Second stage management:
Operative birth is not routinely required for the second stage but may be necessary if the BP is poorly controlled, woman has symptoms of severe cerebral irritability, or progress is inadequate. The decision should be made about forceps delivery or cesarean section.
The Third stage management:
• active management is more appropriative: Oxytocin 10 IU bolus IV for third stage is indicated.
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