Final answer:
The assessment that indicates the effectiveness of atropine sulfate administration is when the client appears calm and relaxed.
Step-by-step explanation:
The correct assessment that indicates the effectiveness of atropine sulfate administration is option 3: The client appears calm and relaxed.
Atropine sulfate is an anticholinergic medication that blocks excess acetylcholine and acts as an antagonist to muscarinic acetylcholine receptors. It is commonly used before electroconvulsive therapy (ECT) to reduce excessive secretions and to prevent bradycardia during the procedure.
Option 1, a heart rate of 48 beats/minute, would not indicate the effectiveness of atropine sulfate, as a decreased heart rate is not a desired outcome. Option 2, a dry mouth, is a common side effect of atropine administration and does not necessarily indicate its effectiveness. Option 4, the client falling asleep, is also not an assessment of atropine's effectiveness.