ECG Interpretations and Treatments Help Please...

Music in My Heart · Sep 8, 2012

"Easier" way? I don't know what way you're using so it's hard to say.

What I found worked best for me was to really understand the electrophysiology of the heart... from there, it's pretty simple to figure out why the rhythms look the way that they do and why medications have the effects that they do.

For example, you know that depolarization is supposed to initiate in the SA node, propagate through the atria, and shows on the EKG as a P wave... no P wave, no SA node firing and no atrial depolarization. Lots of signal prior to QRS, lots of atrial activity (a-fib or a-flutter...)... is it organized at all? flutter... nope? fib

The basics really are pretty simple.

I can recommend a zillion books... my favorite is "The Only EKG Book You'll Ever Need" by Malcolm Thaler. Dale Dubin's book is also good but a little too slow IMO.

nursingstudent_tutor · Sep 9, 2012

CCRN I have some great notes for ECG reading and treatments. Email me if you need help.

wish_me_luck, BSN, RN · Sep 9, 2012

I'll try my best to explain some stuff. The first poster is correct is saying that you must understand what each wave is. The p wave deals with atrial depolarization, QRS complex is ventricular depolarization, and the T wave is ventricular repolarization.

There are several things you are looking at when reading a strip. First, the seconds. It's done in 6 second strips. There's 30 big blocks in a 6 second strip, which at the top of the strip there will be 3 long lines in the 6 seconds. The first thing you have to decide is if the rhythm is regular. Look at the R part of the QRS complex. Take a paper and mark where each R is and see if they are equal. If they are, it's regular; if not it's irregular. Second, look at the heart rate. You get this from counting each R in the 6 second strip and multiplying by 10. Third, look at the PR interval. It's the length of the p wave right before the QRS complex. It's supposed to be 0.10-0.20 sec. It's approx. the equivalent of two and a half tiny boxes. The thinner it is, the lower the sec. Fourth, look at the QRS complex. It's supposed to be 0.04-0.12 sec. The same with the QRS complex, the thinner it is the lower the sec. and the longer it is the higher the seconds.

Then, you have to interpret the strip based on those things.

There are many possibilities. Some basic ones are: normal sinus rhythm (regular rhythm, normal HR which is 60-100, normal PR interval and normal QRS complex); sinus bradycardia (regular rhythm, below 60 bpm heart rate, normal PR interval, normal QRS complex sec); sinus tachycardia (regular rhythm, 101-150 HR, normal PR interval, normal QRS complex sec); Supraventricular tachycardia-SVT (regular rhythm, 151-250 or greater bpm, normal PR interval and normal QRS complex sec.; the p wave may be present and normal or it may be within the T wave due to the high number of contractions); atrial flutter (rhythm is regular, HR- there's the atrial HR and Ventricular HR. Atrial HR is high due to the "f" waves and the HR based on the R wave can be normal or not; like I mentioned, there are "f" waves which the f stands for flutter and they look saw toothed and there are multiple "f" waves per QRS complex; QRS complex sec are normal); atrial fibrillation (rhythm is irregular, HR can vary, no "p" wave or it will look like little squiggles, and there is a present QRS complex and T wave; there is no "p" wave due to the fact in A. Fib the atria quiver instead of contracting); Ventricular tachycardia (regular rhythm; increased HR--obviously because it's tachycardia, no "p" wave, QRS complex present but longer than the normal 0.04-0.12 sec); Ventricular Fibrillation (rhythm unmeasurable; HR is 0; PR interval and QRS complex unmeasurable; there's coorifice and fine. Coorifice has higher waves than fine. Both just look like scribbles and non-readable waves); asystole (unmeasurable rhythm, HR is 0, unmeasurable PR interval and QRS complex; just a straight line or wavy line) There are many other rhythms; then there is what's called a PVC (no "p" wave and the QRS complex is longer than 0.12 sec; happens within an underlying rhythm; either unifocal or multifocal. Unifocal means there is only one site of origin and multifocal means there's multi sites of origin. If there are two unifocal PVCs then they will look the same; two multifocal PVCs look different from each other. There's also the pattern of the PVC: bigeminy which is every other complex is a PVC, trigeminy which is every third complex is a PVC, or quadriminy which is every fourth complex is a PVC; if two PVCs happen right after the other without a complex of the underlying rhythm in between, it is a couplet. That's the basics of PVCs.)

How you treat the dysrhythmia depends on what it is and whether or not the pt is symptomatic/unstable. Assuming you treat them; all of them get oxygen. Sinus bradycardia is treated with atropine (anticholinergic that increases HR); sinus tachycardia depends on what it is from-- fear/anxiety is usually something like Ativan/calming techniques, hypovolemia is fluids like NS and LR and D5W, etc.; SVT is calcium channel blocker, syn. cardioversion, and lowering the HR with valsalva manuever; A flutter is cardioversion and calcium channel blocker; the same with Atrial Fib. and they can also require a pacemaker (think about it-- the SA node is in the right atria, so anything with the atria or involving the SA node can get to the point of requiring a pacemaker); V. Fib is CPR, defibrillator, lidocaine, and epinephrine and V tachycardia depends on whether it's pulseless/unstable. If it is then it's CPR, defibrillator/cardioversion, lidocaine, epi....the whole nine yards LOL. Stable is cardioversion. Asystole or pulseless electrical activity (PEA) is CPR and lidocaine/epi. Do not shock asystole!!!! It can damage the myocardium. Pulseless Electrical Activity means there's activity on the monitor but the pt has no pulse. So, make sure you treat the pt and not the monitor.

I hope this helps. I am not a nurse yet (take boards this week) but I find EKG strips interesting and have been looking at them and will eventually take an offical EKG class when I get money. But those are the things you have to consider looking at a strip and when you look at the treatment.

Good luck. :)

wish_me_luck, BSN, RN · Sep 9, 2012

Oh, and when you syn. cardiovert, you synchronize it with the "R" part of the QRS complex, otherwise it will shock on the T wave and you will throw the pt into a ventricular dysrhythmia such as V Fib. There is no wave to synchronize an "unsynchronized cardioversion/defib" to, and is usually done when the patient is in V Fib already.

metal_m0nk, BSN, RN · Sep 10, 2012

Good stuff, wish_me_luck.

Just want to add that before treating a-fib with cardioversion it may be wise to consider anticoagulating since pooled blood can clot.

wish_me_luck, BSN, RN · Sep 10, 2012

Thanks, triquee and thanks for the additional info. :)

KBICU · Sep 10, 2012

http://Www.skillstat.com

If that link doesnt work just type in 'skill stat ecg' to google :)

turnforthenurse, MSN, NP · Sep 16, 2012

Good stuff, wish_me_luck.
Just want to add that before treating a-fib with cardioversion it may be wise to consider anticoagulating since pooled blood can clot.

Definitely. But once a patient becomes hemodynamically unstable, you would want to cardiovert.

OP, what helped me was repetition. And a good EKG book. I really like ECG Workout by Jane Huff.

nurseprnRN, BSN, RN · Sep 18, 2012

I don't really understand what "the seconds" means. Many EKG strips you review will not be six seconds, exactly, in length, so multiplying the QRSs in one x10 may or may not give you an accurate rate. Also, six seconds of any irregular rate won't tell you much.

Knowing what the EKG measures and how will help you understand what you're looking at. EKG recording started in the golden age of physiology research in the late 1800s-early 1900s when Einthoven figured that the cardiac muscle, like skeletal muscle, had something to do with electricity. He stuck electrodes under the skin of willing volunteers and looked at the spikes that resulted. They looked different depending on where he stuck the needles, and if he pulled the paper underneath the moving recorder the spikes could be timed and counted.

Now, you can't go sticking needles in people like this, so his next stop was to put the people in pickle barrels full of brine (an ELECTROlyte solution, means..."conducts electricity" Aha!) and stuck the electrodes around the barrel. This way he could standardize his recordings so he could compare them to one another.

Well, you can't go sticking sick people in pickle barrels, so eventually they figured out how to use the skin electrodes we have now. After a lot of physiology researchers got into the act, they decided to standardize their methods so they could compare them all. That is why you now have EKG paper with the little squares on them, arranged in big boxes of 25 small ones. The paper goes under the recorder at a fixed rate such that each small box = 0.04 seconds, so each big box = .20 seconds. So there are 300 big boxes in one minute. SO if you have a beat that happens in every big box, that's a rate of 300/minute (eek). Every other box = 300/2, 150/minute. Every third box, rate is 300/3, 100/minute. Every 4th box, 300/4, 75/minute. See the pattern? Of course this works for regular rates or regularly irregular rates only. Irregularly irregular rates, you're better off counting for a minute.

The up-and-down axis is voltage, as in, how much electricity is being measured. Great big fat hypertrophic ventricles that generate a lot of electricity in that muscle mass make great big spikes (seen in chronic hi BP, for one). Sick, crappy, thin ventricles that have very little oomph make smaller ones. This too is part of the standardization of EKG recording. There will be a square wave somewhere in there that will show the calibration.

About those electrode placements-- what's that all about? Well, you will remember that electrical current passes through the heart along a regular pathway (normally), from SA node thru the atria to the AV node and through the ventricles, left and right bundles. This makes a nice coordinated contraction, emptying atria into ventricles and then wringing the ventricles out like a washcloth to squeeze the blood out to the aorta and pulmonary artery. We sometimes need to know where those pathways are disrupted, because that could be an indication of pathology in the related area.

Imagine you are at the baseball park in Philadelphia, and the best pitcher in baseball, Steven Strasburgh, is throwing a sinkerball-- it goes straight from the mound to the catcher, but drops down as it approaches. Imagine you are at first base looking at the path of this ball-- it appears to go from your right to your left, dropping at the end. If you had to draw that, it would be a dropping line from R>L. If you are standing at third base, it appears to go from your left to your right, dropping, so your line would be L>R, dropping. If you are standing on second base (not playing second), pretty much all you'll see is a small dot that drops but it's hard to see where, because you're not in a good position to see the whole path of the ball if the ball is moving away from you; that line would be very short, and drop a little bit. And if you're in the rafters looking down at the field between the mound and the plate, you'll see a ball going straight from the mound to the catcher but you won't see the drop at all, just the straight path, so that line might go top-to-bottom of the page, straight.

This is what the different electrodes do. The give you pictures of the electrical motion (the ball) but you see different waves depending on where you look. As it turns out, there are better places to see the ventricles, or the atria, or subsets of all of these. Part of learning how to read a 12-lead is knowing what leads, or groups of leads, look at what part of the heart best. I will let you look those up...but a hint: precordial leads, the ones on the front of the chest, look at the anterior heart; one lead group includes AVF (for "foot") and that looks at the inferior part (closest to the feet)... check it out. That's how they know it's an anterior infarct or an inferior one, or a septal or lateral, by what leads show the characteristic changes of ischemia and infarct best.

Cool, uh?

Music in My Heart · Sep 19, 2012

I don't really understand what "the seconds" means. Many EKG strips you review will not be six seconds, exactly, in length, so multiplying the QRSs in one x10 may or may not give you an accurate rate. Also, six seconds of any irregular rate won't tell you much.

Knowing what the EKG measures and how will help you understand what you're looking at. EKG recording started in the golden age of physiology research in the late 1800s-early 1900s when Einthoven figured that the cardiac muscle, like skeletal muscle, had something to do with electricity. He stuck electrodes under the skin of willing volunteers and looked at the spikes that resulted. They looked different depending on where he stuck the needles, and if he pulled the paper underneath the moving recorder the spikes could be timed and counted.

Now, you can't go sticking needles in people like this, so his next stop was to put the people in pickle barrels full of brine (an ELECTROlyte solution, means..."conducts electricity" Aha!) and stuck the electrodes around the barrel. This way he could standardize his recordings so he could compare them to one another.

Well, you can't go sticking sick people in pickle barrels, so eventually they figured out how to use the skin electrodes we have now. After a lot of physiology researchers got into the act, they decided to standardize their methods so they could compare them all. That is why you now have EKG paper with the little squares on them, arranged in big boxes of 25 small ones. The paper goes under the recorder at a fixed rate such that each small box = 0.04 seconds, so each big box = .20 seconds. So there are 300 big boxes in one minute. SO if you have a beat that happens in every big box, that's a rate of 300/minute (eek). Every other box = 300/2, 150/minute. Every third box, rate is 300/3, 100/minute. Every 4th box, 300/4, 75/minute. See the pattern? Of course this works for regular rates or regularly irregular rates only. Irregularly irregular rates, you're better off counting for a minute.

The up-and-down axis is voltage, as in, how much electricity is being measured. Great big fat hypertrophic ventricles that generate a lot of electricity in that muscle mass make great big spikes (seen in chronic hi BP, for one). Sick, crappy, thin ventricles that have very little oomph make smaller ones. This too is part of the standardization of EKG recording. There will be a square wave somewhere in there that will show the calibration.

About those electrode placements-- what's that all about? Well, you will remember that electrical current passes through the heart along a regular pathway (normally), from SA node thru the atria to the AV node and through the ventricles, left and right bundles. This makes a nice coordinated contraction, emptying atria into ventricles and then wringing the ventricles out like a washcloth to squeeze the blood out to the aorta and pulmonary artery. We sometimes need to know where those pathways are disrupted, because that could be an indication of pathology in the related area.

Imagine you are at the baseball park in Philadelphia, and the best pitcher in baseball, Steven Strasburgh, is throwing a sinkerball-- it goes straight from the mound to the catcher, but drops down as it approaches. Imagine you are at first base looking at the path of this ball-- it appears to go from your right to your left, dropping at the end. If you had to draw that, it would be a dropping line from R>L. If you are standing at third base, it appears to go from your left to your right, dropping, so your line would be L>R, dropping. If you are standing on second base (not playing second), pretty much all you'll see is a small dot that drops but it's hard to see where, because you're not in a good position to see the whole path of the ball if the ball is moving away from you; that line would be very short, and drop a little bit. And if you're in the rafters looking down at the field between the mound and the plate, you'll see a ball going straight from the mound to the catcher but you won't see the drop at all, just the straight path, so that line might go top-to-bottom of the page, straight.

This is what the different electrodes do. The give you pictures of the electrical motion (the ball) but you see different waves depending on where you look. As it turns out, there are better places to see the ventricles, or the atria, or subsets of all of these. Part of learning how to read a 12-lead is knowing what leads, or groups of leads, look at what part of the heart best. I will let you look those up...but a hint: precordial leads, the ones on the front of the chest, look at the anterior heart; one lead group includes AVF (for "foot") and that looks at the inferior part (closest to the feet)... check it out. That's how they know it's an anterior infarct or an inferior one, or a septal or lateral, by what leads show the characteristic changes of ischemia and infarct best.

Cool, uh?

I love the explanation...

ccshops · Sep 24, 2012

Wow! Thank you all so much for the reply. Got lots of good information. Thanks again.