Obstetric Nurse Pharmacology in Obstetrics Flashcards

A patient is experiencing a postpartum hemorrhage that has not responded to uterine massage or an initial bolus of IV oxytocin. The provider orders carboprost tromethamine. The nurse should question this order if the patient has a significant history of which of the following conditions?

Answer: Asthma

Carboprost tromethamine (Hemabate) is a prostaglandin F2-alpha analogue used to treat postpartum hemorrhage. A major side effect is bronchoconstriction, which can be life-threatening in a patient with a history of asthma. While it should be used with caution in patients with hypertension or renal disease, a history of asthma is a significant contraindication.

A nurse is managing a labor augmentation with an IV oxytocin infusion. The fetal heart rate tracing shows a Category I pattern, but the nurse notes uterine contractions are occurring every 1.5 minutes and lasting 90-100 seconds. What is the nurse's priority action?

Answer: Decrease the oxytocin infusion rate.

The patient is experiencing uterine tachysystole (more than five contractions in 10 minutes). Even with a reassuring (Category I) fetal heart rate tracing, the first action is to address the excessive uterine activity by reducing or stopping the causative agent. Decreasing the oxytocin infusion is the priority intervention to reduce contraction frequency and prevent potential fetal compromise. While other actions are appropriate, managing the oxytocin dose is the first step.

A client at 29 weeks gestation is being treated for preterm labor. The provider orders a course of betamethasone. What is the primary therapeutic goal of administering this medication?

Answer: To accelerate fetal lung maturity

Betamethasone is an antenatal corticosteroid whose primary purpose is to stimulate the production and release of surfactant in the fetal lungs. This action helps to accelerate lung maturity and reduce the risk and severity of neonatal respiratory distress syndrome if the baby is born prematurely. It does not act as a tocolytic to stop contractions.

Fifteen minutes after the placement of an epidural, a laboring client's blood pressure drops from 125/80 mmHg to 90/50 mmHg. The fetal heart rate tracing shows a prolonged deceleration. Which of the following interventions should the nurse perform FIRST?

Answer: Place the patient in a left lateral position and administer an IV fluid bolus.

Maternal hypotension is a common side effect of neuraxial anesthesia due to sympathetic blockade. This can lead to decreased uteroplacental perfusion and fetal distress, as evidenced by the deceleration. The priority is to correct the cause. Placing the patient in a lateral position displaces the uterus off the vena cava, and administering a rapid IV fluid bolus increases intravascular volume, both of which will help restore blood pressure and perfusion.

A provider orders an IV antihypertensive for a patient with a blood pressure of 175/118 mmHg due to preeclampsia with severe features. Which medication order should the nurse question if the patient has a history of bronchial asthma?

Answer: Labetalol

Labetalol is a non-selective beta-blocker that can cause bronchospasm, which is dangerous for a patient with asthma. Hydralazine and nifedipine are first-line IV and oral agents, respectively, that do not carry this specific risk and would be safer alternatives in this patient.

A client at 30 weeks gestation is admitted with preterm labor. The nurse is preparing to administer a tocolytic medication. Which of the following agents is generally avoided after 32 weeks gestation due to the risk of premature closure of the fetal ductus arteriosus?

Answer: Indomethacin

Indomethacin is a nonsteroidal anti-inflammatory drug (NSAID) that works by inhibiting prostaglandin synthesis. Prostaglandins are necessary to keep the fetal ductus arteriosus patent. Using indomethacin, especially after 32 weeks of gestation, increases the risk of premature constriction or closure of this vessel, which can lead to fetal complications such as pulmonary hypertension.