Hello everyone! First topic here :) as said in the title, I have an EKG question. I am getting ready to take boards soon and I have accepted a job on a step down unit in a hospital, so I'm trying to refresh myself on cardiac.
I am an LPN but I don't have any experience with EKG's, other than how to apply the leads. And of course, we had a quick lecture on how to read EKG's in RN school but I'm still a bit confused. Please correct me if I'm wrong, but from my own research, an MI has to be in certain leads before it can be diagnosed?
I understand the basics of a STEMI and NSTEMI but I'm confused about the actual leads part. How can an MI be seen only in certain leads? I may be way off here but if someone could clarify or lead me to a good resource, I would appreciate it. Thank you!!!
The positions of the limb leads is incorrect in that diagram. Limb leads need to be on the limbs, not the torso. The latest ena journal has a great article on the science behind lead placement. Don't know if i can link to it directly.
Specializes in Med Surg/ICU/Psych/Emergency/CEN/retired.
The positions of the limb leads is incorrect in that diagram. Limb leads need to be on the limbs, not the torso. The latest ena journal has a great article on the science behind lead placement. Don't know if i can link to it directly.
Barabara Drew has published a huge amount of literature about incorrect lead placement and how it can lead everyone down the wrong road. I get the ENA Journal but am way behind. You've inspired me to read that article.
This is not a promise, but on my boards I definitely didn't need to recognize a STEMI on a 12-lead. (There were probably questions about what to do when one had alread been diagnosed by an MD, but that's different!) A standard bedside monitor (often shows Lead II) 6-second strip should let you see the pt's rate & rhythm. How long is the PR-interval? Is it consistent? Is there one P wave for each QRS complex? What is the overall rate? What interventions would you expect based on your observations of the monitor and of the patient (short of breath, lethargic, pulseless, eating breakfast and talking on the phone)? When should you call the doctor?
Even once you're on your unit, I'd imagine you will use bedside monitors or telemetry packs, with a 12-lead being ordered when something changes. This could include a pt complaint of pain, a rhythm change on the bedside monitor, syncope, electrolyte imbalances even though the pt says they feel fine, etc... Then, the 12-lead needs to be seen by the MD right away.
OK, thought experiment time. You are at a baseball field. I use this analogy because most people understand the rudiments of baseball enough.
You are sitting in the stands behind first base. You are holding a piece of glass up such that you can see the pitcher and the catcher. When the pitcher throws the ball to the catcher, you trace its path n the glass. The line goes from your right to your left, yes? And because it's a sinker, the line slopes down to your left. OK?
Good. Now go sit at third base with a fresh piece of glass while the pitcher throws the same pitch. Now you're drawing a line that goes from your left to right, and drops down. Right?
OK. Now this is a little tricky. You get a fresh piece of glass and sit behind home plate, so the ball is coming right towards you. However, as you draw its path on the glass in front of you, it starts in about the middle of the piece and then drops a little bit, straight down as it approaches you. So you have a short line going from maybe middle to near the bottom. You can't really tell how far it has traveled from the pitcher's mound to the plate, only that it dropped down as it left the pitcher's hand and approached the catcher.
Last, you get one of those fancy drones and hover above the field, prone with your feet pointing towards second base and your head pointed towards home plate. You watch the same pitch. You see it going straight, but because of your angle you can't perceive the drop, so you draw a straight line on the glass from the bottom of the glass to the top, as you hold it.
On which one(s) of those tracings will you be best able to tell how much the ball is dropping the most? Right, the ones where you were looking from first and third. You'll see a little bit of a drop from your seat at home, but not as clearly. You won't see the drop at all from up above the field because your angle is wrong for that.
On which one(s) will you be able to tell if the ball has crossed the plate between the batter's knees and axillae? Not from the ones at first and third, because you can't tell if the pitch was inside or outside of the plate from that angle. Not from the one in the sky, because you can see if it goes over the plate but not if it's above the axillae or below the knee. You'll get the best views of all of those features from behind the plate (which is why the home plate umpire calls balls and strikes, that is, in or out of the strike zone).
With EKGs, you're not looking at the flight path of the ball, but you're looking at the path the electrical impulse takes going from the SA node to the AV node through the ventricular conduction system (bundles). You can see its path through a particular place better from some vantage points than others. You can see P waves really well in lead II because that's where the machine has the best angle on the impulse passing through the atria, for example- it approaches the lead (line goes up) and then moves away from it (line goes down). The QRS points up in some leads and then down, as the impulse moves towards it and the away. In other leads, it's moving away first and then comes towards, so the QRS complex is downward first, then rises.
Alterations in what's known to be normal conduction patterns indicate, well, abnormal conduction, from dead or cranky cells, injury, or abnormal distance traveled (wider complexes). All taken together tells you what's going on in there.
Specializes in Flight Nursing, Emergency, Forensics, SANE, Trauma.
The positions of the limb leads is incorrect in that diagram. Limb leads need to be on the limbs, not the torso. The latest ena journal has a great article on the science behind lead placement. Don't know if i can link to it directly.
I posted for the V leads. Earlier I posted about about the limb leads.
Thank you everyone for replying. I have a better picture of what's going on now, concerning EKGs and lead placement. I know my experiences and interpretations, treatments etc. will come with time and experience on the floor, I just wanted a little extra boost before I started work. Thank you all again!
Look it up on YouTube. Type in 12-lead EKG. Once you watch a couple of simulations you'll never forget it. You'll understand how vectors work, reading axis, understand BBB, etc.
Hello everyone! First topic here :) as said in the title, I have an EKG question. I am getting ready to take boards soon and I have accepted a job on a step down unit in a hospital, so I'm trying to refresh myself on cardiac.
I am an LPN but I don't have any experience with EKG's, other than how to apply the leads. And of course, we had a quick lecture on how to read EKG's in RN school but I'm still a bit confused. Please correct me if I'm wrong, but from my own research, an MI has to be in certain leads before it can be diagnosed?
I understand the basics of a STEMI and NSTEMI but I'm confused about the actual leads part. How can an MI be seen only in certain leads? I may be way off here but if someone could clarify or lead me to a good resource, I would appreciate it. Thank you!!!
Hi! Maybe I can help some. I am a paramedic (been in EMS for 10 years) and an RN. I just got my RN last week and yet to work in the hospital. However, cardiology is what I love. Limb leads go on the limbs. Remember - white on the right. Smoke over fire. These 4 electrodes (this is in the field-not in the hospital-although very similar) make up 3 leads- I, II, III. When the 6 chest electrodes (I am being very specific with terminology here - they are called V leads but they are not actually leads) are added to the chest you will have a total of 10 electrodes that creates 12 leads. Each LEAD has a positive electrode and a negative electrode. This creates 12 different images of the left ventricle shot from 12 different angles. Remember: SALLY. or actually, SALI
Septal - V1 V2
Anterior V3 V4
Lateral V5 V6 I AVL
Inferior II III AVF
An MI will show up as ST elevation (unless it is an anterior MI in which case you will see ST depression). The MI must be confirmed in 2 or more contiguous leads. Sometimes you can confirm with reciprocal changes. 12 leads are not 100% diagnostic. Labs are where the confirmation comes. However, a 12 lead is an awesome tool. Hopefully this helps and does not confuse you. I was trying to be very specific in my terminology because there is a vast difference between an electrode and a lead. This may be more than you want but when you can look at a 12 lead and see a possible MI these are the things we use as paramedics. Axis deviation is also helpful but I will save that. Last thing: The reason you see ST depression rather than elevation in the anterior leads is because the artery is on the back side of the heart so the picture is actually "upside down" - so to speak. You can take your 12 lead and hold it in front of a mirror or flip it upside down and you can then see the ST elevation in V3 and V4.
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Fish4jibs
8 Posts
ALS UK includes blocks, STEMi and arrhythmias and even medication related ecg abnormality.