2
Peer #1
MondayNov 28 at 8:01pm
A few months ago, while working in recovery on the Endoscopy unit at my hospital, I had a patient who I was recovering after he had an EGD performed to determine if the new mass found in his stomach was cancerous. The patient already had a history of lung cancer and, before that day, was currently in remission. I am unsure of how long his remission was. I remember he was in his mid-80s, and he was being scoped as an outpatient case. His wife accompanied him for his procedure. Upon receiving report from the CRNA, or nurse anesthetist, I noticed his heart rate was increased between the high 90s and low 110s. The CRNA had mentioned that his heart rate had been increasing when they were getting him ready to leave the procedural room but did not mention any significance of cardiac issues in his medical history. The CRNA notified the anesthesiologist who, upon further assessment, instructed me to notify him if the heart rate did not improve once the patient woke up. I managed to wake the patient up and after about 15 minutes, and a fit of coughing due to the lavage performed during the bronchoscopy, he felt fine and stated he was ready to go home. Although the patient was awake and looked well, I noticed his heart rate was still increased, and the rate was even higher than when he slept, somewhere between the 110s and mid 120s. I asked the patient if he felt okay, and he mentioned that his heart felt like it was racing even though he was rested. I asked him and his wife if he was currently seeing a cardiologist, and they both told me no, he’s never had any cardiac issues in the past. I notified the anesthesiologist who gave me orders to obtain a 12-lead ECG which showed he was in A-fib RVR, or rapid ventricular response. The proceduralist was notified who consulted cardiology. They both came and saw the patient, and after assessing him, determined that he would have to be admitted to further observe his new onset of atrial fibrillation.
I believe his advanced age was a factor in how his pharmacokinetic and pharmacodynamic processes altered his response to the sedative used during his procedure. The sedative used by the CRNA was propofol, which is a drug often used by anesthesia to sedate patients for a procedure or operation. Pharmacokinetics is defined as “the study of drug movement throughout the body” (Rosenthal & Burchum, 2021). Pharmacodynamics is defined as “the study of the biological and physiologic effects of drugs on the body and the molecular mechanisms by which those effects are produced” (Rosenthal & Burchum, 2021). Through pharmacokinetics, processes of the concept include absorption of the drug causing movement from its administrative site to the blood; distribution which is the drug’s movement from the circulatory system to tissues and eventually into cells; metabolism which involves alterations in drug structure; and excretion which involves movement of the drug out of the body. Blood flow is important to consider when administering medications, especially among elderly patients, like the patient described in my scenario. Older patients have a positive correlation with a decrease in systemic circulation, making dose adjustments tricky when it comes to medication administration. With decreased blood flow, there runs the risk that the medication may have a longer half-life with patients with a decreased systemic circulation, causing medications to linger in the patient’s circulation for a longer time, resulting in a delay in the patient’s pharmacokinetics. Although that can be beneficial with some medications depending on the desired effect, it can also be detrimental when age is taken into consideration. This is where calculating height and weight is important when considering dose for elderly patients (Rosenthal & Burchum, 2021). This is where pharmacodynamics plays a role. Propofol, although can be safe when administered carefully under the supervision of a doctor or advanced practitioner, is also a drug that has a short half-life due to its route of administration, in this case, intravenously. Now did this play a factor into the reaction the patient experienced post-op? It is a possibility. However, it can also be possible that the patient’s history of cancer contributed to his new onset of a-fib. Stress could have also played a factor. Discovering that you have cancer yet again can take a toll on an individual and cause them to have a stress response which can sometimes lead to effects on the heart.
A plan of care I would develop for this patient would be to consult cardiology and have the patient admitted to the hospital for further evaluation. I would anticipate cardiology to order a 12-lead ECG if one wasn’t ordered already, and possible have the patient run tests such as an echocardiogram to determine any underlying cardiac issues that may have developed to cause the alteration in cardiac rhythm. I would also consult oncology along with gastroenterology to develop a plan for the care of the patient associated with the newly discovered stomach cancer from the mass found during the EGD. From there, we can develop a plan that would provide optimal care for the patient.
References
Rosenthal, L. D., & Burchum, J. (2021). Lehne's pharmacotherapeutics for advanced practice nurses and physician assistants. St. Louis : Elsevier
Peer 2
Melanie Owens
Pharmacokinetics is characterized by the process of a drug through the body by four basic processes absorption, distribution, metabolism, and excretion (Rosenthal & Burchum, 2020). Absorption, which is the how the medication moves into the blood stream from the site of origin. Distribution is the movement from the blood to the tissues, and then into the cells. Metabolism is the breakdown of the drug structure. Excretion is the process of the drug leaving the body. All medications do not absorb or excrete the same way. Pharmacodynamics is basically the study of how a drug effects the body whether negatively or therapeutically.
