Beta blockers are a class of medication commonly used to lower blood pressure. Beta blockers slow down the heart and reduce the force with which the heart contracts, ultimately lowering blood pressure. In this video, I'll teach you my mnemonic to remember the names, uses, mechanisms, and side effects of beta blockers.
Welcome to the Pixerize Pet Store! Take a look at this beta fish. This beta fish should help you remember that we are talking about beta blockers.
Beta fish for beta blockers, get it? Beta blockers slow the heart rate and lower blood pressure by blocking beta adrenergic receptors throughout the body, but especially on the heart. These beta receptors are normally acted upon by catecholamines like epinephrine and norepinephrine to stimulate the sympathetic or fight-or-flight response, which includes increase in heart rate and blood pressure.
Beta blockers unsurprisingly work by blocking beta receptors, which stops or inhibits the body's fight-or-flight response. As a result, heart rate and blood pressure decrease, which we'll cover in more detail later. For now, just picture this beta fish to anchor yourself to this scene on beta blockers. Next, notice our pet shop customer looking at the fish.
Of course, it's a kid, since kids are fascinated by pet stores, right? And like any kid, this kid loves her lollipops. Whoops, while the girl's mom wasn't looking, she dropped a lollipop into the fish tank. I guess the fish does look hungry, the way it's gasping for air like that. By the way, this lollipop is here to remind you of the lol ending that all beta blockers have in common.
Get it? Lollipops. For the lol ending of beta blockers. Some common examples of beta blockers ending in a lol are propranolol, metoprolol, atenolol, and carvetolol. Just know that if you see a drug that ends with lol, you should know that we're talking about a beta blocker.
Got that? Now, let's talk about what's gone wrong with the fish tank here. It sure looks like this water pump isn't in very good condition. Notice the big cracks in it? Because the pump is broken, it is having a hard time pumping water into the tank.
No wonder why the fish is gasping. Coincidentally, this weak pump should help you remember that beta blockers weaken the contractility of the heart, reducing the heart's ability to pump blood through the body. Kind of like the weakening of this pump here, you feel? It's worth noting that in addition to reducing the heart's contractility, beta blockers also have a noticeable effect in slowing down the heart rate, which we'll cover in a later symbol. Both of these factors contribute in reducing the total volume of blood pumped out of the heart per minute, which is formerly known as the cardiac output.
Long story short, just remember beta blockers reduce the contractility of the heart, which ultimately decreases cardiac output. Uh-oh, because of the broken pump, water is backing up into this pipe, causing it to burst. Based on the water spraying out, I'd say there's a lot of pressure in this pipe.
Speaking of pressure, you can use this high pressure bursting pipe to help you remember that beta blockers are used to treat high blood pressure or hypertension. The reduction in cardiac output we just talked about causes a decrease in blood pressure, which can help treat hypertension. Since less blood is pumping into the blood vessels, the blood vessels will in turn be under lower pressure. Makes sense?
Next, take a look at how the water bursting out of the pipe is spraying right onto this sign. This is one of those I heart pets signs you always see in pet stores. Anyway, notice how this soggy wet sign is ripping right through the middle of the heart.
You know, since wet paper rips pretty easily, right? By the way, this ripped heart is our symbol for heart failure. You know, a wet, broken heart for heart failure? This is here to help you remember that beta blockers can also be used to treat heart failure, particularly in the chronic setting. It might seem counterintuitive to use a drug that decreases cardiac output to treat heart failure, so let me explain why we do this.
You see, by decreasing the heart's contractility, beta blockers reduce the workload of the heart. Over time, this prevents pathologic remodeling and growth of the heart that can eventually lead to the death of the patient by way of arrhythmias or heart attacks. As such, beta blockers improve the long-term survival of patients with heart failure. Now that we've covered the clinical uses of beta blockers, let's talk about some side effects you should be aware of. Because the water pump is broken, the water inside isn't getting oxygenated.
This has caused our betta fish to swim at the top of the tank, gasping for oxygen. This fish, gasping for air, reminds me of bronchospasm, a side effect seen with the use of beta blockers. After all, when someone is experiencing bronchospasm, they are gasping for air just like this fish, right?
Technically, not all beta blockers cause bronchospasm. Beta blockers are actually divided into two types, selective and non-selective beta blockers. Selective beta blockers selectively target beta-1 receptors which are mainly found in the heart and don't really cause bronchospasm.
In contrast, non-selective beta blockers are messier and hit both beta-1 and beta-2 receptors. These beta-2 receptors are found in many places but notably are found in the airways of the lungs, where they keep the airway open. So, by blocking beta-2 receptors in the lungs, beta blockers can lead to the side effect of bronchospasm. On test day, the most important thing for you to remember is that as the nurse, you should watch for signs of bronchospasm in patients taking beta blockers. Signs like wheezing, coughing, and difficulty breathing.
Also, it's important for you to remember to use caution when administering beta blockers to patients with asthma and COPD. Makes sense, right? Because patients with asthma and COPD are at a higher risk for bronchospasm. Man, this girl sure is spending a lot of time looking at all the fish in the store. It looks like her mom is starting to get impatient.
See how she's looking at her watch as if complaining that her daughter is being too slow? By the way, this slow time is our recurring symbol for bradycardia, because time ticking slowly should remind you of the heart beating slowly. Get it? Slow time for slow heart rate.
One of the adverse effects of beta blockers is bradycardia, or heart rate that is too slow. This should make sense given that we already mentioned how beta blockers slow down the heart. As a nurse, you will want to monitor the patient's heart rate before administering beta blockers. And don't forget to educate your patients to do the same when they are taking beta blockers at home. Next, it looks like this girl doesn't want her mom to see how many lollipops she's eaten.
Look at how she's hiding these empty lollipop wrappers in her pocket. These hidden empty candy wrappers are our symbol for masking hypoglycemia, another side effect of beta blockers. Get it? since empty candy wrappers remind me of low sugar or hypoglycemia.
And these candy wrappers are being hidden from sight or masked from view of mom here. Beta blockers can hide the symptoms of hypoglycemia, just like this girl is hiding the evidence of empty lollipop wrappers. One of the typical signs of hypoglycemia is tachycardia. But as you know, beta blockers work to slow down the heart rate. This means that hypoglycemic patients will not present with tachycardia like they normally do, and may not even recognize themselves falling into dangerously low blood sugar levels.
As a nurse, be on the lookout for other signs of hypoglycemia instead. Things like lightheadedness, sweating, and nausea, especially in your diabetic patients. Alright, we're about done with beta blockers.
Let's summarize what we've learned and get out of this pet shop. Beta blockers are a class of medications that all share the lol ending, like propranolol, atenolol, carvetolol, and metoprolol. These drugs are commonly used to treat hypertension and chronic heart failure. Beta blockers work by reducing contractility of the heart and slowing down the heart rate.
So watch out for the side effects of bradycardia and make sure to check your patient's pulse before administration. Other important adverse effects to watch out for with beta blockers include bronchospasm and the masking of hypoglycemia. That's it for beta blockers! Wow, I can't believe we spent our whole time at this pet store in the fish section.
But if it helps you get ready for test day, then time in the fish section is time well spent. Thanks for visiting, come back soon!