Final answer:
Peripheral edema is a sign of possible heart failure, a side effect of metoprolol, where excess fluid accumulates in the body's tissues. It is critical to monitor and report peripheral edema as it may require urgent medical treatment.
Step-by-step explanation:
The nurse should instruct the client to monitor for and report the development of peripheral edema because this can be an indication of heart failure, which is an adverse effect of metoprolol. Peripheral edema involves the accumulation of excess water in the tissues, typically in the extremities, and can result from underlying heart conditions. When the heart is inefficient, such as in heart failure, fluid can get "backed up" in the body causing swelling. This condition can also lead to pulmonary edema, where excess fluid accumulates in the lungs, making it difficult to breathe. Early signs of heart failure can include fatigue, shortness of breath, and, in more serious cases, peripheral edema that could manifest as swelling in the feet and ankles.