Final answer:
The nurse suspects liver dysfunction due to the development of nausea and jaundice in a client on carbidopa-levodopa and will review liver function tests first, including liver enzyme levels.
Step-by-step explanation:
Given that the client has developed nausea and jaundice after being on the medication combo of carbidopa-levodopa for a year, the nurse may suspect a complication involving the liver. Jaundice is often a sign of liver dysfunction, which can occur due to drug-induced liver injury. As part of the laboratory tests, the nurse will review liver function tests (LFTs) first, since they are the key indicators of liver health. These tests typically measure levels of liver enzymes, bilirubin, and albumin. An elevation in liver enzymes such as aspartate aminotransferase (AST) and alanine aminotransferase (ALT) can suggest liver injury, which might be caused by the medications. If liver dysfunction is confirmed, the healthcare provider will consider alternate treatments and closely monitor the patient's condition.