Registered Practical Nurse (RPN) Practice Test

Before administering lithium carbonate to a 76-year-old client, what should the nurse assess?

1. Liver function

2. Renal function

3. Cardiac health

4. Blood glucose levels

The correct answer is: Renal function

When considering the administration of lithium carbonate to an elderly patient, assessing renal function is crucial due to lithium's pharmacokinetics and its potential effects on the body. Lithium is primarily excreted by the kidneys, and any impairment in renal function can lead to accumulation of the drug in the body, increasing the risk for toxicity. Older adults may have decreased kidney function due to age-related changes or prevailing health issues, making it essential to evaluate renal health before initiating treatment. Renal function tests, like serum creatinine and blood urea nitrogen (BUN), provide important information regarding how well the kidneys are filtering and excreting substances, including lithium. While liver function, cardiac health, and blood glucose levels are also important health considerations, they are not as directly related to lithium administration as renal function. For instance, lithium does not undergo significant metabolism in the liver, so liver function may not impact lithium therapy as much. Similarly, while cardiac health is pertinent, especially since lithium can affect heart rhythm at higher doses, the immediate necessity for renal assessment takes precedence for safe medication administration. Monitoring blood glucose levels is also essential in diabetic patients but is not specifically tied to the pharmacological effects of lithium itself.