eMedicine Specialties > Emergency Medicine > Obstetrics & Gynecology
Placenta Previa: Treatment & Medication
Updated: Aug 10, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
- Multimedia
Treatment
Prehospital Care
- The key to prehospital care of placenta previa is to ensure hemodynamic stability of the patient and transfer to an appropriate facility.
Emergency Department Care
- Because of the potential morbidity and mortality secondary to profuse bleeding, obtain immediate gynecologic consultation, if available. Before gynecologic consultation or transfer, the hemodynamic stability of the patient should be addressed. This includes the establishment of 2 large-bore intravenous access lines with intravenous crystalloids or blood products, as necessary.
- Obtain continuous fetal monitoring, if available.
- If the fetus is preterm and immediate delivery is unnecessary (eg, fetus <37 weeks' gestation and hemorrhage not present), the patient may be treated expectantly on an outpatient basis.
- If the fetus is reasonably mature (ie, >37 weeks' gestation) and the patient is in labor or if severe hemorrhage is present, therapy is directed at the delivery of the fetus. The patient should receive crystalloids and/or blood, and the patient should be transferred to the operating room with double set-up conditions.
- A trial of labor may be considered for anterior marginal previa, including oxytocin (Pitocin) augmentation.
- Guidelines for the diagnosis and management of placenta previa have been established.3,4
Consultations
- Consult an obstetrician.
Medication
The goal of ED treatment in patients with placenta previa should be directed at the hemodynamic stability of the patient. The primary therapeutic agents should be intravenous crystalloids and/or transfusions.
Recent studies are now using prothrombin complex and recombinant factor VII to control hemorrhage associated with obstetric complications and placenta previa.
Corticosteroids
Steroids may be administered after consultation with a gynecologist, if vaginal bleeding is mild and intermittent, if the patient is not in labor, and if gestation is less than 37 weeks.
Betamethasone (Celestone)
Helps promote fetal lung maturity.
Adult
Assess dosing after consulting with obstetrician
Pediatric
Not established
Effects decrease with coadministration of barbiturates, phenytoin, and rifampin; decreases effect of salicylates and vaccines used for immunization
Documented hypersensitivity; systemic fungal infections
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Increases risk of multiple complications, including severe infections; monitor adrenal insufficiency when tapering drug; abrupt discontinuation of glucocorticoids may cause adrenal crisis; hyperglycemia, edema, osteonecrosis, myopathy, peptic ulcer disease, hypokalemia, osteoporosis, euphoria, psychosis, myasthenia gravis, growth suppression, and infections are possible complications of glucocorticoid use
Tocolytics
Some specialists advocate tocolytics to promote the time for expectant management of symptomatic placenta previa. They should only be used after consultation with an obstetrician. A recent study seems to suggest that the use of tocolytics increases the duration of pregnancy and increases the baby's birth weight without causing adverse effects on the mother and the fetus.
Magnesium sulfate
Nutritional supplement in hyperalimentation. Cofactor in enzyme systems involved in neurochemical transmission and muscular excitability. In adults, 60-180 mEq of potassium, 10-30 mEq of magnesium, and 10-40 mmol/L of phosphate per day may be necessary for optimum metabolic response. Discontinue treatment as soon as desired effect is obtained. Repeat doses are dependent on continuing presence of patellar reflex and adequate respiratory function.
Adult
Assess dosing after consulting with obstetrician
Pediatric
Not established
Concurrent use with nifedipine may cause hypotension and neuromuscular blockade; may increase neuromuscular blockade observed with aminoglycosides and potentiate neuromuscular blockade produced by tubocurarine, vecuronium, and succinylcholine; may increase CNS effects and toxicity of CNS depressants and betamethasone; may increase cardiotoxicity of ritodrine
Documented hypersensitivity; heart block; Addison disease; myocardial damage; severe hepatitis
Pregnancy
A - Fetal risk not revealed in controlled studies in humans
Precautions
Magnesium may alter cardiac conduction, leading to heart block in digitalized patients; respiratory rate, deep tendon reflex, and renal function should be monitored when electrolyte is administered parenterally; caution when administering magnesium dose because magnesium may produce significant hypertension or asystole; in overdose, calcium gluconate, 10-20 mL IV of 10% solution, can be administered as antidote for clinically significant hypermagnesemia
Terbutaline (Brethine)
Acts directly on beta2-receptors to relax uterine contractions.
Adult
Assess dosing after consulting with obstetrician
Pediatric
Not established
Concomitant use with beta-blockers may inhibit bronchodilating, cardiac, and vasodilating effects of beta agonists; concomitant administration of MAOIs with beta sympathomimetics may result in a hypertensive crisis; concurrent administration of oxytocic drugs such as ergonovine with terbutaline may result in severe hypotension
Documented hypersensitivity; tachycardia resulting from cardiac arrhythmias
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Maternal death has occurred through intracellular shunting; terbutaline may decrease serum potassium levels, which can produce adverse cardiovascular effects, decrease is usually transient and may not require supplementation
More on Placenta Previa |
| Overview: Placenta Previa |
| Differential Diagnoses & Workup: Placenta Previa |
 Treatment & Medication: Placenta Previa |
| Follow-up: Placenta Previa |
| Multimedia: Placenta Previa |
| References |
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References
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Milosevic J, Lilic V, Tasic M, Radovic-Janosevic D, Stefanovic M, Antic V. [Placental complications after a previous cesarean section]. Med Pregl. May-Jun 2009;62(5-6):212-6. [Medline].
[Guideline] Royal College of Obstetricians and Gynaecologists (RCOG). Placenta praevia and placenta praevia accreta: diagnosis and management. Oct 2005;[Full Text].
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Further Reading
Keywords
placenta previa, disseminated intravascular coagulopathy, vaginal bleeding, pregnancy complications, obstetric complications, total placenta previa, partial placenta previa, marginal placenta previa, low-lying placenta previa, internal cervical os, abnormal placental implantation, uterine bleeding, treatment, diagnosis
