Final answer:
The main sign of right-sided heart failure is peripheral edema, which is best evidenced by weight gain due to fluid retention. Swelling occurs because of increased venous pressure leading to fluid leakage from the capillaries into the tissues, especially in the extremities. Edema is detected by persistent indentation upon applying pressure to the swollen area, referred to as pitting edema.
Step-by-step explanation:
A frequent sign of right-sided heart failure is peripheral edema, which manifests as swelling in the extremities due to fluid accumulation. The correct answer to the question about what evidence indicates peripheral edema is b) Weight gain. This symptom arises because with right-sided heart failure, there is an increase in pressure in the vena cavae leading to blood pooling in the systemic circulation, particularly in the lower limbs when standing or sitting. This results in fluid leak from the capillaries and subsequent tissue swelling.
In pulmonary edema, which is associated with left-sided heart failure rather than right-sided, the patient would primarily experience difficulty in breathing due to fluid buildup in the lungs. However, the symptoms for right-sided heart failure can include fatigue, swelling in the feet and ankles, and weight gain due to fluid retention. It's important to note that while edema can be quickly checked for by pressing a finger into the suspected area and observing if an indentation remains, known as "pitting."