A nurse is monitoring a 32-year-old primigravida at 41 weeks gestation when the fetal heart rate (FHR) tracing shows repetitive late decelerations with minimal variability. The cervix is 4 cm dilated, and contractions are occurring every 5 minutes. What is the nurse's priority assessment?

When a fetal heart rate tracing shows repetitive late decelerations with minimal variability, the immediate clinical priority is to determine the fetal acid-base status. This is achieved through fetal scalp stimulation or fetal scalp blood sampling to assess pH, base deficit, and lactate levels. This assessment distinguishes between a fetus that is physiologically compensating and one with true metabolic acidemia, guiding the decision for emergency cesarean or operative vaginal delivery.

Concurrently, initiate intrauterine resuscitation measures: reposition the mother to a left lateral position, administer a 500-1000 mL IV fluid bolus of lactated Ringer's solution, provide 10 L/min of oxygen via non-rebreather mask, and consider reducing uterine activity by discontinuing oxytocin or administering a tocolytic (e.g., terbutaline 0.25 mg subcutaneously). These interventions aim to improve uteroplacental perfusion and fetal oxygenation while preparing for possible expedited delivery.

Continuous communication with the obstetric provider is essential. Document the FHR pattern, interventions performed, maternal and fetal response, and the plan for delivery. If fetal scalp pH is less than 7.20 or if the tracing does not improve with resuscitation measures, prepare the patient for immediate delivery. Neonatal resuscitation team should be notified and present at delivery due to the high risk of a depressed newborn requiring advanced support.