Final answer:
The nurse should first discontinue the oxytocin infusion and then proceed with measures to assess and improve fetal well-being, such as supplemental oxygen for the mother, maternal positioning, and notifying the obstetrician for potential emergency intervention.
Step-by-step explanation:
When a client's membranes rupture during labor augmented with oxytocin infusion and variable decelerations in the fetal heart rate occur, the nurse’s actions are crucial. First, the nurse should discontinue the oxytocin infusion, as it can lead to overly strong or frequent contractions that might further compromise the fetal oxygen supply. Next, the nurse should assess the fetal heart rate pattern and maternal vital signs, administer supplemental oxygen to the mother, and place the mother in the left lateral position to improve fetal blood flow.
Notify the obstetrician immediately because variable decelerations can indicate umbilical cord compression possibly requiring an emergency birth. A quick assessment of amniotic fluid for meconium, which can indicate fetal distress, is also important. Continuous electronic fetal monitoring would be necessary to closely observe the fetal heart rate pattern for further signs of distress. Preparations for a potential operative delivery such as vacuum, forceps, or cesarean section should be made in collaboration with the obstetric team.