Cardiac: Electrical Cardioversion Vs Defibrillation

You're listening to Nitty Gritty Nursing with Nurse M, where she breaks down the nitty-gritty basics of nursing concepts.

Hello and welcome back to Nitty Gritty Nursing with Nurse M. Today I'm gonna break down cardioversions versus defibrillations. And I'm gonna first start with the concept of cardioversions, which is oftentimes an elective procedure. Uh this one, if you think about it, easy way to remember this is defibrillation starts with a D, and that's for dead people.

Cardioversion starts with a C, and that's for alive people. There's not a good rhyming reason for that, but D is for dead, so defibrillation's for dead people. Cardioversion is an ele is we can do it either chemically or electrically. From an electrical standpoint, that's what I'm going to talk about today. An electrical cardioversion is a synchronized countershock to convert an undesirable rhythm.

to a stable rhythm. And this can be an elective procedure, often provo performed by some sort of provider for some type of stable tachy dysrhythmia. And y oftentimes these are rhythms that are kind of resistant or haven't um worked converted properly with medical um therapies that have been tried. Or it can also be uh for an emergent procedure for

someone that is hemodynamically unstable, um, in a ventricular or superventricular tachy dysrhythmia. But if this is the instance, these patients even though they're hemin hemodynamically unstable, they will still be conscious, they will still have a pulse, so we still classify it as a cardioversion and not a defibrillation, because again, Defibrillation is for dead. But

Electrical cardioversion is when we use a lower amount of energy than we would use with defibrillation. And again, that makes sense because these patients often have a heartbeat and they're live and they're talking and they're properly circulating. They just have an abnormal rhythm that needs to be converted versus the individual that is clinically dead, we would need to defibrillate with a much higher electrical voltage because we need to really shock the heart awake.

And so if you're the nurse doing an electrical cardioversion, there's some key things that you want to make sure have occurred before you proceed or actually cardiovert the patient. And the first one is Oftentimes because these are elective, we need to make sure that a timeout is done before the procedure. This ensures that you are working with the right patient. You have the consent form that's been signed, the patient doesn't have any questions.

And then you've got all of your ABCs covered. So they've got their airway and you've got oxygen on them. And you've got their breathing they're breathing down fine, but you might need um some sort of respiratory, emergent respiratory equipment like an amboo bag. And you've got your code cart nearby because again, we're messing with the heart.

So you want to make sure that all of your emergency equipment is present and you wanna make sure that your defibrillation pads are in place and choose the jewels based off of what the provider asks you to. For the cardioversion, all based on their order. And yes, it is defibrillation pads that we're using for cardioversion because the cardioversion is just. Oftentimes the

an elective procedure at a lower voltage, but we use the same pads because that's how we have to deliver the electricity. And then you must push this is the key with electrical cardiovasion, you must push the sink button on the defibrillation machine And we do this to prevent R on T phenomenon. And basically what that means is that it allows the shock to be provided safely away from the T wave. And think back to your basic rhythms.

P Q R S T and we don't want to deliver the shock between the R and the T. Because then we will cause an R and T phenomenon and we can put these patients into a lethal arrhythmia. Now, once you hit the sync button on your defibrillating machine, you should see a rhythm, and then you should be looking for the indicator above that rhythm, which oftentimes on many machines is a tiny little dot above the QRS.

Complex that tells you that it is in sync mode. Once you've confirmed that it is in sync mode and you're ready to cardiovert this individual electrically,

you need to give them sedation, they are wide awake, and to be k electrically shocked whilst awake to alter your heart's rhythm and pattern is incredibly painful. So don't do that. From a testing perspective, I've read in the books that You know, yes, during that procedure you want to make sure that your skin is clean and dry where the electrode pads are, because if you have someone incredibly hairy, for example, how do you think the electrode pads are gonna stick?

not very well. So you have to really make sure that you've got good contact between the pads and the skin of the individual. And then I've I've read in in some books that you want to stop oxygen during the procedure. in order to prevent a fire hazard. That clinically, that makes sense to me when I read about that, but I'm going to tell you right now that in my shop, like I guess what that you do in book world versus what you're doing in real life is two different things because

I've never stopped someone's oxygen, uh, when I've done an electrical cardioversion. And the other big thing which we do always make sure that we do during a procedure is to make sure that no one is touching the bed or the client. when delivering the counter shock because it that shock can have a little bit of transference and whoever's touching the person or the bed. Again, think about this logically. Hospital beds are full of metal. It conducts really well. So

people that are touching it often get a little bit of a jolt themselves. Now, once the electrical cardia version is done, your priority assessment is of this patient is going to include airway and breathing and making sure that they Still have an airweight, they're still breathing on their own. If you followed the book version and you turned off the oxygen, you would immediately resume giving them oxygen and then assess their vital signs, assess their level of consciousness.

look at the rhythm. Did what we do just work? And then we wanna basically, from a nursing perspective, monitor for indications of successful response From the conversion to a sinus rhythm, and what does that look like in a human? It's gonna be do they have strong peripheral pulses? Is their blood pressure adequate? You know, you can even go further to say like, do they have an appropriate amount of urine output because

That means that their kidneys are adequately being perfused. And then look at their actual skin on the chest. Where the pads were once you've removed them, because we want to look to make sure that there aren't any substantial burns, especially around the edges of the pads.

uh because that is quite painful. The main thing that I've seen when I've removed the pads is normally patients will walk out after an elective cardioversion with basically the equivalent of a sunburn. And they hit those heal. Now, the three big rhythms that

I've most commonly done an electrical cardiaversion on are gonna be superventricular tachycardia. Again, the origin of where that tachyarrhythmia is originating from is above the ventricles, hence supra super superior or above the ventricles, atrial flutter, and then the biggest one that I've done electrical cardioversions on have been in a controlled outpatient setting have been atrial fibrillations.

And when we think about these sorts of rhythms, oftentimes we have patients in atrial fibrillation that will live

for months or years on an anticoagulant if we might be trying to um ha see if they'll tolerate it. Some don't or some just can't be on anticoagulants. But before you go to shock them, you'd better make sure that they have been properly taking their anticoagulant because news flash, if they haven't, they could have developed potentially a clot, and then as soon as their heart goes into like a normal sinus rhythm, uh you have the potential to now send that clot

you know, to the brain. And that could be bad'cause strokes are bad. Now, defibrillation.

Defibrillation. is an asynchronous countershock used to terminate pulses ventricular tachycardia or ventricular fibrillation. The difference is that we don't care where we shock because in pulses ventricular tachycardia The ventricles are beating way too fast and they're

hemodynamically unstable, you know, they're unconscious. You might you can't feel a pulse. So they're not actually perfusing. These are life threatening rhythms, and the same with ventricular fibrillation. There's no rhyme or reason behind how the heart is beating because it's not perfusing. And these patients are unconscious. This is not an elective procedure. This is an emergent procedure. And it follows in track with the advanced cardiac life support treatment modality.

And so we are shocking these individuals at a much higher voltage. And that can be anywhere between 120 to 360 joules, depending on if the machine that you're using is classified as a biphasic or a monophasic. machine and basically what that means is if it's a biphasic you have

two pads on the person, so electricity's coming in from both angles to the heart. And if it's a monophasic, it's basically going from one pad to the other, which is why monophasic requires higher voltage because it's not getting attacked from both sides. it's just going down through one side. So here's the deal with the defibrillation. Once you defibrillate a lethal arrhythmia, if you're defibrillating a lethal arrhythmia, whether that's pulsus ventricular tachycardia,

or ventricular fibrillation. This per these people do not have a pulse. They are clinically dead. You follow the ACLS treatment modality, which is shock them and then you immediately resume CPR and continue that for five cycles or two minutes and you do the

five cycles or two minutes and then you do a rhythm check, et cetera, et cetera, follow the ACLS protocol. And if you get successful conversion uh from a ventricular fibrillation to a normal sinus, rhythm, for example, uh, then you would follow basically whatever your hospital's protocol is for patients who obtain ROSC, which is what we call a R-O-S-C, return of spontaneous

circulation. A classic nursing school question that they like to ask in order to assess whether or not you understand the difference between uh cardioversion and defibrillation, for example, or just like your thought process of how would you uh treat or approach this patient is they'll give you a rhythm or they'll just tell you in the root of a question like you're on shift and your patient

You look at the monitor at the nurses station and suddenly it looks like it's uh ventricular fibrillation, like what's your first priority? And your first priority should always be A, to assess your patient, because it could be that very well that they're in their room brushing their teeth.

And every time they go in to do uh, you know, the toothbrushing motion, they could be knocking on the electrode lead, causing artifact which will mimic and kind of look like ventricular fibrillation. But if you're in the room and it's witness, the key the key is. If it's pulseless ventricular tachycardia or if it's ventricular fibrillation, you defib. So if it's V fib, you defib, call a code, uh no sync and do the whole CPR protocol.

So that's my quick summary of electrical cardioversion versus defibrillation. Again, with electrical cardioversion, oftentimes it's elective. Patients are awake and we sedate them for this. You will synchronize the machine with the QRS to avoid the RNT phenomenon. The jewels that we give, much lower. These patients better have a consent form available. And then again, EKG monitor in place.

Follow your emergency protocols. Do they have a an airway? Are they breathing? Is there oxygen? Is there a code cart? And then you cardiovert and assess your patient looking for adequate cardiac output versus defibrillation, which are Patients that are clinically dead, if it's a V fib, you D fib, this is an emergency. If it's

V fib or pulsus ventricular tachycardia, they don't have cardiac output. There is no output going to them. So every single organ is dying. We use much higher voltage, anywhere between, you know, What did I say initially? Here's the key unconscious. You have them on an EKG monitor, you defibrillate, and then you follow the advanced cardiac life support protocol or if you're in the field and you just have an AED that shows up.

And it the machine says, shock advised. And it should they shock the patient, go back onto the chest and start CPR before emergency personnel gets there. So that's all I've got on those two. Go forth and keep on learning.