Following IV magnesium sulfate administration, how can the nurse determine the medication is effective?

The effectiveness of magnesium sulfate administration in the context of pregnancy and labor is primarily measured by its ability to reduce uterine contractions, particularly in cases of preterm labor or conditions like preeclampsia. Magnesium sulfate acts as a central nervous system depressant and provides smooth muscle relaxation. Therefore, when the medication is effective, a nurse would expect to observe a decrease in the frequency, intensity, and duration of contractions. This reduction can help to prolong pregnancy and improve fetal outcomes by allowing more time for fetal development.

Maintaining a respiratory rate greater than 12 breaths/min does not directly indicate the effectiveness of magnesium sulfate; instead, it is more of a parameter to monitor for potential side effects or toxicity related to the medication. Likewise, while achieving specific blood pressure readings can be important in cases where magnesium sulfate is used for hypertensive disorders, it is not a direct measure of the medication's effectiveness in addressing uterine activity. Overall, observing a decrease in contraction activity is the most relevant assessment to determine if magnesium sulfate is working as intended.