Final answer:
The priority intervention when administering captopril to a heart failure patient is to instruct them to ask for assistance when rising to prevent falls due to blood pressure changes. Monitoring potassium levels is also important due to the risk of hyperkalemia with ACE inhibitors.
Step-by-step explanation:
The priority intervention for a client with heart failure who is being administered captopril (Capoten) is to instruct the client to ask for assistance when arising from bed. This is because captopril, an angiotensin-converting enzyme (ACE) inhibitor, can cause a rapid drop in blood pressure, leading to symptoms such as dizziness or lightheadedness, particularly when moving from a sitting or lying position to standing (a condition known as postural hypotension). Ensuring the patient asks for assistance can help prevent falls and injuries.
It is also important to monitor the potassium level, as ACE inhibitors can lead to an increase in serum potassium, causing hyperkalemia, rather than hypokalemia. Therefore, monitoring for signs of hyperkalemia is necessary, but not the priority intervention in this immediate context. Answering option B emphasizes safety as the immediate consideration.