Final answer:
The nurse must be alert for signs of Respiratory depression as an expected side effect of intravenous magnesium sulfate, which is due to its depressive effect on the CNS. This can lead to decreased respiratory efforts and requires close monitoring.
Step-by-step explanation:
If a client is admitted to the medical ward with convulsions and is receiving intravenous magnesium sulfate, the nurse must be particularly alert for signs indicating expected side effects of the drug. Among the options provided, Respiratory depression is an expected side effect of magnesium sulfate. This is because magnesium has a depressive effect on the central nervous system and can lead to decreased respiratory effort. Signs that may be observed in the patient include shallow or slow breathing. The nurse needs to monitor respiratory status closely to ensure patient safety.
The other options listed have different associations. Hyperreflexia is generally not associated with magnesium sulfate; rather, it might be seen in conditions of magnesium deficiency. Hypertension is generally not a side effect of magnesium sulfate, as it is more commonly associated with vasodilatory effects, often leading to decreased blood pressure. Flushing might occasionally be seen as a mild and transient side effect but is not typically a major concern when administering magnesium sulfate.