NURS 6521 Module 2: Cardiovascular and Respiratory Systems

MODULE 2: AT A GLANCE – CARDIOVASCULAR AND RESPIRATORY SYSTEMS

WHAT’S HAPPENING THIS MODULE?

Module 2: Cardiovascular and Respiratory Systems is a 2-week module, Weeks 2 and 3 of the course. In this module, you will examine how patient factors may influence pharmacokinetic and pharmacodynamic processes of pharmacotherapeutics used in the treatment of cardiovascular and respiratory disorders. You will also explore and suggest drug therapy plans for asthma and analyze the stepwise approach for asthma treatment and management.

INTRODUCTION

Alterations of the cardiovascular system can cause serious adverse events and may lead to death when not treated in a timely and safe manner. Unfortunately, many patients with cardiovascular disorders are unaware until complications appear. In clinical settings, patients often present with symptoms of several cardiovascular disorders, making it essential for you, as the advanced practice nurse, to be able to recognize these symptoms and recommend appropriate drug treatment options.

This week, you examine the impact of patient factors that may lead to changes in pharmacokinetic and pharmacodynamic processes on patient drug therapy for cardiovascular disorders. You also explore ways to improve drug therapy plans for cardiovascular disorders based on patient factors and overall health needs.

LEARNING OBJECTIVES

Students will:

Analyze the influence of patient factors on pharmacokinetic and pharmacodynamic processes
Analyze the impact of changes in pharmacokinetic and pharmacodynamic processes on patient drug therapies
Evaluate drug therapy plans for cardiovascular disorders

PHARMACOTHERAPY FOR CARDIOVASCULAR DISORDERS

…heart disease remains the No. 1 killer in America; nearly half of all Americans have high blood pressure, high cholesterol, or smoke—some of the leading risk factors for heart disease…

—Murphy et al., 2018

Despite the high mortality rates associated with cardiovascular disorders, improved treatment options do exist that can help address those risk factors that afflict the majority of the population today.

As an advanced practice nurse, it is your responsibility to recommend appropriate treatment options for patients with cardiovascular disorders. To ensure the safety and effectiveness of drug therapy, advanced practice nurses must consider aspects that might influence pharmacokinetic and pharmacodynamic processes such as medical history, other drugs currently prescribed, and individual patient factors.

Reference: Murphy, S. L., Xu, J., Kochanek, K. D., & Arias, E. (2018). Mortality in the United States, 2017. Retrieved from https://www.cdc.gov/nchs/products/databriefs/db328.htm

[Music] One of the missions of this course is to straddle the basic sciences and the clinical sciences. Many years ago, Sir William Osler said, “One cannot become a competent clinician “without the full knowledge of human physiology “and pathology. “Without it, one flounders along “in an aimless fashion, never able to gain “an accurate conception of disease, “practicing a sort of popgun pharmacy, “hitting now the malady and again the patient, he himself not knowing which.”

This week, Dr. Norbert Myslinski examines how categories of drugs working through different mechanisms can provide a synergistic effect creating more treatment options. So often in hospitals and the doctors’ offices and also in medical schools and nursing schools and dental schools, there is this dichotomy between the two. I mean, you first learn the basic sciences, then you forget about those and you go to the clinics, I think you learn the real stuff, but we want to do with this course is to produce a bridge between the two.

And make the understanding of the clinical portions more relevant by knowing the basic science– knowing the basic science that we have. Another way in which groups are important is synergism. In pharmacology, we have a concept where the effect of two different drugs is greater than the sum of the individual drugs and which is very important when you combine different drugs and especially when you have groups of drugs or categories that work via different mechanisms of action.

You may have a same end result of different categories of drugs, but they work via different mechanisms. And if you do that, you’re more likely to get a synergistic effect than if they all worked via the same mechanism. Some drugs work via same mechanism no matter what their effects are, okay? For instance, aspirin. Aspirin has many effects, all right? Aspirin is an analgesic that alleviates pain. Aspirin is anti-inflammatory, alleviates inflammation. Aspirin is an anticoagulant for the blood.

Aspirin also is antipyretic. It decreases body temperature, okay? But how does it do it? It has many effects. By the way, all drugs have multiple effects. No drug only has one effect. All drugs have more than one effect. But how does aspirin do all these different effects? Via the same mechanism. And that’s through the inhibition of a certain compound in the body called prostaglandins. So inhibition of the synthesis of prostaglandins produces all of them. Okay? There are many different types of prostaglandins and therefore we have different effects in there, Okay?

So if we have two different drugs, they work via the inhibition of prostaglandins. Say, aspirin and Tylenol, right? They’re not going to have a synergistic effect. They’ll have an additive effect, right? But if you have, for instance, a narcotic like morphine, okay? And then you also have Tylenol, you can have a synergistic effect with those two. Although with Tylenol and aspirin, there is a ceiling. You can take two or three tablets and that’s the maximum pain relief you’re going to get. No matter if you take five or 10 after that, you may have gastric distress, but it’s more of an effect, it’s a ceiling.

With morphine though there is no ceiling. You just keep going, going, going, you get more and more pain relief, you know, until your respiration shuts down and you die. So if we look at hypertension, that silent killer. That’s one disorder that we have a wealth of groups and categories of drugs working via many different mechanisms. So we can have a very nice synergistic effect. We can tailor-make their pharmacotherapy, you know, so they can control their blood pressure with the least amount of side effects and they can function in society.

For example, you have your ACE inhibitors, you have your angiotensin inhibitors, you have your beta-blockers, you have your calcium-channel blockers, you have your diuretics, all of them can reduce blood pressure, all of them work via different mechanisms. There are two types of blood vessels that go up, which is the carotids and the vertebrals and then they go into a little area here and distributed throughout the brain and one of the most common causes of disability that we have is stroke.

Now, stroke is when you have a deprivation of oxygen going to a part of the brain. And that’s usually due to one of three things. Either there is a buildup of a clot in that blood vessel, a primary site, so the blood stops going to that area or you have a clot that breaks off from a different part of your body, more likely from the left side of heart because you may have atherosclerosis, build up of fatty tissues and clots there and if one breaks off, it can go into your brain and to clog a blood vessel, that will be quick or you can have a weak blood vessel wall so that it blows up like a balloon, a balloon is aneurysm and eventually it bursts and when it bursts then you have a stroke in that part of the area of brain.

Now, the symptoms of a stroke on many patients that nurses treat for chronic time periods, the symptoms of a stroke can be quite varied. You know, as many functions that are functions of the brain depending upon where the stroke is, depending upon where the stroke is, okay? For instance, if it happens here at the back of the brain, you’ll have a lot of visual symptoms because this is where the brain processes visual information, occipital lobes. If you have one over here in the temporal lobes, that process is hearing, okay?

So you’d have hearing problems, okay? If you have a stroke that affects this part over here, this is somatosensory cortex, you may have a problem with the feeling, touch, and pressure in different parts of your body. Over here is the motor cortex and that has to do with movement. So you may have problems with movement of your body. Okay, so it all depends upon where that injury is and it’s very interesting because when there is a stroke, the main part dies and then the other parts around it shut down and unless treatment is given quickly and drugs can be given that can dissolve a clot real quickly, okay, the part that sort of are not dead yet, but they are affected around there if not treated quickly then that part may also die.

And so when you first have a stroke your symptoms involve not only the dead part, but also the part back here sort of shut down, all right? If you’re treated quickly, if you have the signs of a stroke you have what we call a brain attack then you get right there to the emergency center, you can dissolve the clot, and then you can have reversal of some of the symptoms. Like dysfunction of all these ones around, the dysfunctional ones can come back and we can have reversal of the symptoms, but if you don’t get the treatment, these will eventually die too and the others– those symptoms will stay around for a very long time. And so it all depends upon where the dysfunction is and that determines what kind of symptoms we have.