NURS 6521 Week 1 Discussion Post: Pharmacokinetics And Phar ✓ Solved

NURS 6521 Week 1 Discussion Post Pharmacokinetics and Phar

The advanced practice nurse (APN) needs to understand the pharmacokinetics and pharmacodynamics of medications. Pharmacokinetics is the study of how a drug moves through the body, whereas pharmacodynamics is the study how a drug affects the body (Rosenthal & Burchum, 2018). According to Le (2019), the pharmacokinetics of a medication is dependent on patient factors (sex, age, genetics, and renal function) as well as the chemical properties of the drug. Pharmacokinetics involves the administration, distribution, metabolism, and excretion of a drug (Le, 2019). According to Farinde (2019), pharmacodynamics and pharmacokinetics together assist in describing the relationship between the dose and response of a drug.

The purpose of this discussion post is to select patient case that was observed and how factors influenced the pharmacokinetics and pharmacodynamics processes. The discussion will also review the plan of care for the selected patient case.

Description of Patient CaseThe patient case selected is for a 76-year-old female who was admitted for sepsis of unknown origin. The medical emergency response team was activated to evaluate patient for potential stroke and new onset confusion. The neurologist assessed the patient and ruled out a stroke, but patient was newly confused without explanation. After reviewing the chart, within twenty-four hours, the patient had received their normal medications from home, as well as two doses of vancomycin and one dose of cefepime both given intravenously. The patient had no history of confusion and did not receive any medications for sleep, pain, or sedation. The patient has a slightly elevated creatinine of 1.9 and liver function panel was slightly elevated, but it was not a great concern to team to cause encephalopathy.

Factors Affecting Pharmacokinetic and Pharmacodynamic ProcessesThe factors that can have an effect both the pharmacokinetics and pharmacodynamics of cefepime are the patient’s age and pathophysiological changes that occur from sepsis. According to Isitan, Ferree, & Hohler (2017), cefepime is a fourth-generation cephalosporin antibiotic also known as a beta-lactams and is used to treat a broad spectrum of organisms. Cephalosporins are known to be nephrotoxic due to drug concentrations being high intracellularly (Oliveira, Chaterjee, & Burns, 2016). The time a patient develops encephalopathy is between one and ten days after starting a cephalosporin; thus, clinicians should be aware of the toxic effects of cephalosporins, especially if the patient has known renal failure (Oliveira et al., 2016). The patient is 76 years old, and her kidney function is impaired, delaying the metabolism and elimination of cefepime which may be causing her confusion. The patient also had slightly elevated liver function tests which inhibits the ability to metabolize and excrete cefepime as well. Clinicians should be paying attention to the dosing of cephalosporins in relation to a patient’s kidney and liver function as well as age and have a suspicion of neurotoxicity if the patient presents with new confusion (Isitan et al., 2017).

Personalized Plan of CareThe plan of care developed for this patient would be to immediately stop cephalosporin therapy. According to Oliveira et al. (2016), withholding cephalosporin treatment when neurotoxicity is discovered usually treats the condition immediately, but if cases are much worse, hemodialysis may need to be initiated. The patient’s labs should be monitored for worsening renal and liver dysfunction. For patients at high risk of developing neurotoxicity from exposure to cephalosporin, alternative antibiotics should be evaluated and considered (Payne et al., 2017). Interruption in drug therapy can often resolve the adverse reaction of confusion but can take up to five days to see improvements (Payne et al., 2017). From a nursing perspective, the focus would be on ensuring the patient is safe and comfortable and that the family has an understanding of the circumstances.

Paper For Above Instructions

Understanding pharmacokinetics and pharmacodynamics is essential for advanced practice nurses (APNs) as they navigate the complexities of patient care and medication management. This discussion analyzes the pharmacokinetics and pharmacodynamics associated with a specific patient case involving a 76-year-old female diagnosed with sepsis and newly onset confusion. Through this analysis, critical factors influencing drug behavior in the body and the development of an appropriate plan of care will be assessed.

Pharmacokinetics refers to how a drug is absorbed, distributed, metabolized, and excreted from the body. Each of these processes can vary significantly based on patient-specific factors such as age, sex, genetic makeup, and organ function (Rosenthal & Burchum, 2018). In our patient case, the 76-year-old female has concurrent renal and hepatic impairments, which are critical factors that affect the pharmacokinetics of the medications administered, particularly cefepime and vancomycin. Renal function greatly influences the clearance of many drugs, including beta-lactam antibiotics like cefepime, while hepatic function plays a key role in the metabolism of various drugs.

In contrast, pharmacodynamics deals with the effects of the drug on the body, including its mechanism of action and the relationship between drug concentration and therapeutic effect (Farinde, 2019). In this case, the influence of sepsis on pharmacodynamics is significant, as systemic infections can alter drug responsiveness and the expected therapeutic outcomes.

The patient’s confusion may well be attributed to the interplay of pharmacokinetic and pharmacodynamic factors. Aging affects drug clearance, often resulting in delayed excretion and increased drug levels in the body (Le, 2019). The slight elevation in creatinine noted upon admission indicates a degree of renal impairment, which aligns with a potential accumulation of cefepime in the system. Cefepime is known to have neurotoxic potential, especially when renal function is compromised, and signs of neurotoxicity, including confusion or encephalopathy, can emerge (Isitan et al., 2017). The elevated liver function tests further complicate the pharmacokinetic profile of cefepime as hepatic metabolism is also crucial for drug clearance.

While cefepime is effective against a broad spectrum of organisms, the risk of adverse effects, particularly neurotoxicity, is a legitimate concern. Oliveira et al. (2016) indicate that the onset of encephalopathy can occur anywhere from one to ten days post-administration of cefepime. In the case of this patient, her lack of confusion prior to medication administration and the onset of confusion following exposure to cefepime strongly suggest a drug-related reaction. Additionally, in older adults, pharmacodynamics can also shift, requiring careful monitoring and dosage adjustments to avoid adverse effects.

The management plan for this patient requires immediate modification of her current therapeutic regimen. Given the signs of potential neurotoxicity, the cephalosporin therapy should be discontinued. As highlighted by Oliveira et al. (2016), immediate cessation of cefepime has proven to resolve neurotoxicity in many cases; however, alternative treatment options must be considered to address the underlying infectious process. The patient's renal and liver function should be regularly monitored to evaluate the impact on her overall condition and adjust therapy accordingly.

In addition to monitoring laboratory values, an interdisciplinary approach is necessary for optimal patient care. Collaborating with pharmacists may provide insight into alternative antibiotics that are safer for renal-compromised patients. Payne et al. (2017) emphasize the need for vigilance in identifying neurotoxic potential in patients receiving cephalosporins, particularly among the elderly or those with preexisting conditions. Addressing the family’s needs and providing education on the patient's condition and treatment adjustments are crucial aspects of patient-centered care.

In summary, understanding pharmacokinetics and pharmacodynamics is integral in managing complex cases involving potential drug toxicity. For the 76-year-old female patient admitted with sepsis and confusion, careful consideration of age, renal function, and the pharmacological properties of cefepime underscores the need for tailored therapeutic interventions. Continuous monitoring and interdisciplinary collaboration will enhance patient safety and therapeutic outcomes.

References

• Farinde, A. (2019). Overview of pharmacodynamics. Merck Manual.
• Isitan, C., Ferree, A., & Hohler, A. D. (2017). Cefepime induced neurotoxicity: A case series and review of the literature. Eneurologicalsci, 8, 40-43.
• Le, J. (2019). Overview of pharmacokinetics. Merck Manual.
• Oliveira, B., Chaterjee, S., & Burns, A. (2016). Lesson of the month 2: An easily missed cause of confusion. Clinical Medicine, 16(5).
• Payne, L. E., Gagnon, D. J., Riker, R. R., Seder, D. B., Glisic, E. K., Morris, J. G., & Fraser, G. L. (2017). Cefepime-induced neurotoxicity: A systematic review. Critical Care, 21(1), 1-8.
• Rosenthal, L. D., & Burchum, J. R. (2018). Lehne's pharmacotherapeutics for advanced practice providers. St. Louis, MO: Elsevier.