Which nursing action is critical when administering magnesium sulfate?

Monitoring serum magnesium levels is crucial when administering magnesium sulfate due to the potential for toxicity associated with this medication. Magnesium sulfate is often used in obstetrics for various reasons, including the prevention of seizure activity in women with preeclampsia or eclampsia and as a neuroprotective agent for preterm infants.

Elevated serum magnesium can lead to toxicity, which manifests as symptoms such as respiratory depression, diminished reflexes, hypotension, and cardiac arrhythmias. Regular monitoring ensures that the serum magnesium levels remain within a safe range, allowing for timely interventions if levels begin to rise excessively.

While assessing nutritional intake, administering via a large bore IV, and encouraging ambulation are relevant nursing actions for general care or specific situations, they do not address the specific need to monitor for magnesium toxicity, making the monitoring of serum magnesium levels the most critical action in this context.