NURS 6521 Week 1 Discussion: Pharmacokinetics and Pharmacodynamics Example 2

The human body and pharmacological agents interact in various fashions to cause desired pharmacological effects and adverse outcomes in undesired situations. I encountered a patient named Mrs. B (not her actual name) who was being treated for congestive heart failure in my training. Mrs. B is a 78-year-old black female who had been on treatment for heart failure two months ago. During that admission, she had been brought in because she had bilateral lower limb edema.

Mrs. B was put on furosemide for his edema and heart failure. She was ambulant and reported no leg pain. During the second day on furosemide, she started reporting dizziness. Her blood pressure measured that day was within the normal limits but borderline low. Her physician reassured her that her vitals were fine but there needed some adjustments in the doses of her medications. Her physician was also worried about her kidney function due to her conditions. Therefore, he ordered that Mrs. B be evaluated for serum creatinine, urea levels, and serum potassium and sodium levels.

Mrs. B’s body ad furosemide reacted in various ways to cause the improvement of the edema and the dizziness with lowered blood pressure. Furosemide is the commonest prescribed diuretic and has indications in cardiac, hepatic, pulmonary, and renal diseases (Rosenthal & Burchum, 2020). It has well documented pharmacokinetic profile and pharmacodynamics properties. The route of administration can be parenteral or enteral. Oral administration is usually through oral uncoated tablets or oral disintegrating films (Koh et al., 2021).

The route determines its bioavailability and onset of action after administration. The absorption happens in the gut after oral administration, and metabolism occurs in the liver, after which elimination will take place in the kidneys. This explains the physicians’ concerns about kidney functions. Poor elimination in kidney injury would lead to toxicity of this drug and more adverse events. Furosemide acts in the loop of Henle to promote the excretion of water and potassium.

Therefore, it reduces fluid overload and reduces cardiac output. In so doing, it can lower blood pressure and cause hypotension and dizziness. This explains the phenomenon that Mrs. B was experiencing on the second day of therapy (Khan et al., 2022). Therefore, the pharmacokinetics and pharmacodynamics of furosemide explain the entire phenomena Mrs. B had. This understanding provides the basis for the care plan for this patient.

Individualized Plan for Mrs. B

Mrs. would require rehydration despite still having fluid overload. This would prevent acute kidney injury and furosemide toxicity. Mrs. B is an elderly patient, and the administration of furosemide would require monitoring of sodium levels for this particular population, according to the American Geriatric Society (American Geriatrics Society, 2019). Decreased kidney function among the elderly population would lead to decreased drug elimination and thus toxicity. This plan would also include blood pressure monitoring to prevent orthostatic hypotension and dizziness.

The personalized plan for Mrs. B is based on what furosemide does to the body (pharmacodynamics) and what the body does to furosemide (pharmacokinetics) and the factors influencing these interactions. Age has stood out as a key factor in the pharmacodynamics and pharmacokinetics of furosemide. The diminished physiological capacity of the body in adults influences how they eliminate and metabolize medications. Therefore, nursing interventional adjustments and physical intervention adjustments would be justified in this case.

References

American Geriatrics Society. (2019). American geriatrics society 2019 updated AGS beers criteria® for potentially inappropriate medication use in older adults: 2019 Ags beers criteria® update expert panel. Journal of the American Geriatrics Society, 67(4), 674–694. https://doi.org/10.1111/jgs.15767

Khan, T. M., Patel, R., & Siddiqui, A. H. (2022). Furosemide. In StatPearls [Internet]. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK499921/

Koh, S.-K., Jeong, J.-W., Choi, S.-I., Kim, R. M., Koo, T.-S., Cho, K. H., & Seo, K.-W. (2021). Pharmacokinetics and diuretic effect of furosemide after the single intravenous, oral tablet, and newly developed oral disintegrating film administration in healthy beagle dogs. BMC Veterinary Research, 17(1), 295. https://doi.org/10.1186/s12917-021-02998-4

Rosenthal, L., & Burchum, J. (2020). Lehne’s pharmacotherapeutics for advanced practice nurses and physician assistants (2nd ed.). Saunders. https://evolve.elsevier.com/cs/product/9780323554954