Clinical Scenario

Respond to at least two of your colleagues on two different days by suggesting additional patient factors that might have interfered with the pharmacokinetic and pharmacodynamic processes of the patients they described.

In addition, suggest how the personalized plan of care might change if the age of the patient were different and/or if the patient had a comorbid condition, such as renal failure, heart failure, or liver failure.

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Clinical Scenario

The patient is a tall, lanky 67-year-old male with end-stage renal failure and cirrhosis of the liver.  He presents to the Emergency Department (ED) with an inguinal hernia that he cannot reduce.  He rates his pain 10/10 on a scale of 1-10, with 0 being no pain and 10 being extreme pain.  The patient appears uncomfortable, complains of dizziness, and constipation.  Social history consists of smoking a pack a day or cigarettes for 25 years, moderate alcohol consumption, daily marijuana use, poor diet, and decreased mood.  His medications are centered around pain control and include the use of narcotics every 4 hours.  The patient is given a dose of Toradol 30mg, intravenously (IV).  After ten minutes, the patient is asking for more pain medication.  Fentanyl 50 mcg, IV is given with no pain relief reported by the patient.  Finally, Hydromorphone 1mg, IV is administered.  After an hour, the patient still reports pain 10/10.

Pharmacokinetics and Pharmacodynamics

Pharmacokinetics studies the absorption, distribution, metabolism, and excretion of drugs within the body system (Ball, Dains, Flynn, Solomon, & Stewart, 2019).  The use of pharmacokinetics enables providers to determine the appropriate drug for a patient’s diagnosis.  Pharmacodynamics refers to how the body is affected by the use of certain medications (Fox, Hawney, & Kaye, 2011).  Due to the individualized nature of the human body, finding a drug that responds with minimal side effects are desired.Pharmacokinetics, as it relates to this patient’s pathophysiology, creates difficulty for the patient due to the diagnosis of kidney failure and cirrhosis.  Cirrhosis of the liver prevents the body from absorbing, distributing, and metabolizing the drug.  With significant disease process in effect, it is difficult for the body to absorb the drug at a rate that provides effective pain control.  The first-pass metabolism with hydromorphone is decreased in liver cirrhosis and has a likelihood of high hepatic extraction (Wehrer, 2015).