When providing client care, the nurse identifies a problem and develops a related clinical question. Next, the nurse intends to gather evidence so that the decision-making process in response to the problem and clinical question is evidence-based. When gathering evidence, which consideration is most important?

- Anti-Glycan Neu5Gc Antibodies (AGNA) are antibodies that recognize a carbohydrate antigen called N- glycolylneuraminic acid (Neu5Gc), which is found in animal-derived foods and tissues, but not in humans¹². Humans can incorporate Neu5Gc from their diet into their own cells, which can trigger an immune response and the production of AGNA¹².

- AGNA has been associated with various inflammatory and autoimmune diseases, such as atherosclerosis, rheumatoid arthritis, Crohn's disease, and cancer¹². AGNA may also play a role in the rejection of bioprosthetic heart valves, which are made from animal tissues that contain Neu5Gc¹.

- A client with carcinoma in situ of the left breast is a client with a non-invasive form of breast cancer, where the abnormal cells are confined to the ducts or lobules of the breast. This type of cancer has a high chance of cure with surgery and/or radiation therapy.

- Increased levels of AGNA in a client with carcinoma in situ of the left breast may indicate that the client has an increased risk of inflammation and infection, as AGNA can activate the complement system and recruit inflammatory cells to the site of Neu5Gc expression¹². This may impair the healing process and increase the chances of complications after surgery or radiation therapy.

- Therefore, the practical nurse (PN) should anticipate that the client's plan of care will include the initiation of changes in infection control measures, such as prophylactic antibiotics, wound care, sterile dressing changes, and monitoring for signs and symptoms of infection (such as fever, redness, swelling, pain, or pus). These measures will help to prevent or treat any potential infection and promote wound healing.

Therefore, option A is the correct answer, while options B, C, and D are incorrect.

Option B is incorrect because increasing the client's dietary servings of fruits and vegetables may not have a significant impact on the levels of AGNA or Neu5Gc in the client's body.

Option C is incorrect because limiting the client's fluid intake to avoid hemodilution may not be necessary or beneficial for the client's condition.

Option D is incorrect because avoiding the client's exposure to cold temperatures may not be relevant or helpful for the client's condition.

A high blood urea nitrogen (BUN) level indicates impaired renal function, which can be caused by dehydration, infection, or nephrotoxic drugs. Chemotherapy can damage the kidneys and increase the risk of renal failure. The PN should report this finding to the charge nurse, as it may require fluid replacement, dose adjustment, or discontinuation of the chemotherapy.

The other options are not correct because:

1. Periodic nausea and vomiting are common side effects of chemotherapy that can be managed with antiemetics, hydration, and dietary modifications. They are not as urgent as a high BUN level.
2. Decreased deep tendon reflexes may indicate hypocalcemia, hypomagnesemia, or peripheral neuropathy, which can be caused by chemotherapy or other factors. They are not as urgent as a high BUN level.
3. A platelet count of 135,000/mm3 or 135 x 10^9/L is slightly below the normal range, but not significantly low. Chemotherapy can cause thrombocytopenia, which increases the risk of bleeding. The PN should monitor the client for signs of bleeding, but this finding is not as urgent as a high BUN level.