3.2 Antepartum Complications: Preeclampsia & Third-Trimester Bleeding
Differentiate severe preeclampsia from eclampsia, monitor magnesium sulfate toxicity, and distinguish placenta previa from abruptio placentae.
🎯 Key NCLEX-RN® Clinical Takeaways
- Preeclampsia severe features: BP >= 160/110, proteinuria, hyperreflexia/clonus, epigastric pain (hepatic capsule stretch).
- Magnesium sulfate toxicity: Loss of deep tendon reflexes (first sign), respirations < 12/min, oliguria; Antidote is Calcium Gluconate.
- Placenta previa presents with painless, bright red bleeding and a soft, non-tender uterus; digital cervical exams are strictly CONTRAINDICATED.
- Abruptio placentae presents with painful, dark red bleeding, uterine hypertonicity, and a rigid, board-like abdomen.
Preeclampsia is a systemic vascular endothelial disease of pregnancy characterized by hypertension and end-organ dysfunction. Magnesium sulfate is administered as neuroprotection to prevent eclamptic seizures.
Magnesium toxicity is life-threatening. The nurse monitors patellar reflexes, respiratory rate, and hourly urine output. If reflexes are abolished or respirations fall below 12/min, the nurse immediately stops the infusion and gives IV calcium gluconate.
Third-trimester bleeding requires immediate differential diagnosis. Placenta previa features painless bright red bleeding with a soft uterus; digital exams are strictly prohibited. Abruptio placentae features severe pain, dark blood, and a rigid, board-like abdomen.
⚠️ Common Pearson VUE / NCLEX Traps
- Performing a digital vaginal exam on a pregnant client with painless bright red bleeding before ultrasound rules out previa.
- Failing to stop magnesium sulfate immediately when patellar reflexes are absent and respirations are 10 breaths/min.
Knowledge Checkpoint
A client with severe preeclampsia is receiving a continuous intravenous infusion of magnesium sulfate at 2 g/hour to prevent eclamptic seizures. On hourly assessment, the nurse finds: respiratory rate 9 breaths/min, absent deep tendon reflexes (0/4 patellar), urine output 15 mL over the past hour, and lethargy. What is the immediate priority nursing action?