A client delivered a 10-pound baby girl vaginally 14 hours ago. The nurse applies an icepack to the perineum. The nurse understands that application of ice is used to:

A. While assessing temperature is important for evaluating maternal infection or overall condition, it is not the primary concern when administering magnesium sulfate. Fever does not typically indicate magnesium toxicity, so it is not the priority assessment in this situation.

B. This is the priority assessment because magnesium sulfate can cause respiratory depression if serum levels exceed the therapeutic range. Magnesium acts as a central nervous system depressant and smooth muscle relaxant, which helps inhibit uterine contractions in preterm labor but also poses a risk to respiratory function. The nurse should assess the client’s respiratory rate before initiating the infusion and monitor continuously throughout therapy. A respiratory rate below 12 breaths per minute may indicate early magnesium toxicity, necessitating immediate cessation of the infusion, administration of calcium gluconate as an antidote, and supportive respiratory care.

C. Monitoring blood pressure is important, especially in clients with preeclampsia, because magnesium sulfate can have mild hypotensive effects. However, the most immediate risk of toxicity is respiratory depression, not blood pressure changes. Therefore, while BP is monitored, it is secondary to respiratory assessment in this context.

D. Bowel sounds are part of a routine assessment but are not affected by magnesium sulfate and do not relate to the medication’s most dangerous complications.

A. Fetal hypoxia is typically indicated by abnormal FHR patterns, such as late decelerations, decreased or absent variability, bradycardia, or prolonged decelerations. In this scenario, the FHR shows a normal baseline, moderate variability, and accelerations, all of which suggest adequate oxygenation and fetal well-being.

B. Tachycardia is defined as a baseline FHR greater than 160 beats per minute. Causes of fetal tachycardia can include maternal fever, infection, medications, or fetal hypoxia, but this fetus has a baseline of 135 bpm, which is within the normal range of 110–160 bpm, so tachycardia is not present.

C. Bradycardia is defined as a baseline FHR less than 110 beats per minute. Causes of bradycardia can include prolonged cord compression, maternal hypotension, or congenital heart conditions, but this fetus has a baseline of 135 bpm, ruling out bradycardia.

D. This fetus exhibits a reassuring FHR pattern characterized by a normal baseline indicating adequate cardiac function, moderate variability reflecting an intact autonomic nervous system and good oxygenation, presence of accelerations demonstrating a responsive, well-oxygenated fetus, and absence of decelerations, indicating there is no evidence of uteroplacental compromise or cord compression.