03.05 Atrial Fibrillation (A Fib)

Hey guys! In this lesson we are going to talk about atrial fibrillation, A-fib is a very important rhythm to understand and recognize because of the increased risk for stroke. So let's talk about the characteristics of it, nursing interventions and treatments.

So if y'all remember the SA node initiates the electrical impulse and sends it to the AV node then down the bundle of His right and left bundle branches and purkinje fibers. In atrial fibrillation there are multiple cells in the atria initiating a disorganized electrical impulse causing the atria to quiver at a rate of greater than 300 beats per minute. The atria are not contracting, they are quivering very little blood is going to the ventricles. So blood pools or sits in the atria and it clots up causing an enormous risk for stroke. People with a fib are 5 times more likely to have a stroke versus patients with a normal sinus rhythm. That is why it is so important for us as nurses to identify the rhythm promptly so we can take action. So just like in aflutter, the AV node slows down some of the impulses but sometimes it allows other signals to pass so the ventricles contract at a rate of greater than 100 beats per minute. This is called A-fib with RVR. If my patient has RVR and the ventricles contract faster the cardiac output is decreased. So let's break down the characteristics of a fib and do the 6-step method.

So in step one we need to look at the rhythm and see if it is regular or irregular, so let's count the boxes in between, from here to here we have 21 from here to here we have 14 from here to here 12. So the boxes in between the r waves are inconsistent our rhythm is irregular. Let's do step 2 and count the heart rate and because we have more p waves than QRS we have to count both. In atrial fibrillation it is very difficult to identify the p waves making it very difficult to count them. In a-fib people have a wavy baseline versus the saw tooth appearance on Aflutter. So let’s count our ventricular rate which is 110 since we have a 6 second strip. The 1500 method would be difficult to count with this irregular rhythm because the boxes are not the same in between the R waves. So the best thing to do is to count an apical pulse for a full minute to get an accurate heart rate. But we are going to use the heart rate of 110 beats per minute. In the third step we need to look at the P to QRS ratio, and since there are no obvious p waves it's hard to determine if we have a one to one ratio so it is not measurable. In Step 4 we would need to look at the PR interval again since we have no obvious p-waves this would also not be measurable. In step 5 we need to look at the QRS complex so if we measured from here to here we have about 2 boxes or 0.08 seconds. In Step 6 would be to identify the rhythm which would be atrial fibrillation. So let's recap the characteristics of atrial fibrillation, the rhythm is irregular, the ventricular heart rate varies some patients will have a normal heart rate others will have a heart rate greater than 100 it is difficult to count the atrial heart rate because there are no identifiable P waves and there is a wavy baseline, and because there are no identifiable p waves the P to QRS ratio is not measurable the PR interval is not measurable and the QRS complex is normal. So because atrial fibrillation can cause significant complications let's talk about managing it! Most patients that have atrial fibrillation usually present with palpitations, fatigue lightheadedness and syncope because of decreased cardiac output. Nursing interventions are to determine if it's chronic or acute, some people live with chronic A Fib and that's fine we continue to monitor them as long as their rate is controlled. Make sure they do not have RVR and always obtain a 12-lead EKG as soon as possible to confirm the rhythm. A new onset of A-fib we need to restore them back to a normal sinus rhythm as quickly as possible. Whether it is chronic or acute we have to make sure we monitor them for signs and symptoms of stroke, remember that the atria are not contracting so blood pools in the atria and it clots up if this breaks loose it can cause a stroke. That is why so it is important for them to have anticoagulants to decrease any clots from forming in the atria. So now let's talk about therapeutic management.

Therapeutic management includes assessing the patient and determining if it’s a chronic or acute. Find out if they are an RVR and assess for any signs and symptoms of stroke. A patient that has chronic a-fib needs to be monitored and make sure they are taking their medications including anticoagulants. A patient that comes in with a onset A-fib with a heart rate of 150 is in RVR, cardiac output will be decreased and they may be unstable and symptomatic, we need to convert them back to a normal sinus rhythm as soon as possible. Priorities are to control the ventricular rate with beta blockers or calcium channel blockers sometimes we start them on a Cardizem drip or amiodarone drip to convert them or slow down their heart rate. If this does not work, they will need a cardioversion. If a patient comes into the ER unstable and symptomatic with heart rate of 150 and not taking anticoagulants, we cannot just cardiovert them. The clot may break lose if they are converted into a normal sinus rhythm and the blood clot will go to the brain and cause a stroke. In order to prevent a stroke, patients must first have a TEE- a transesophageal echocardiogram. Basically we stick a tube down their throat and into the esophagus and through ultrasound we make sure there are no clots in the atria. If they don’t have any clots they get cardioverter. If there are clots we will not cardiovert them. This is why it’s so important to find out if they are taking anticoagulants. If a patient has had a couple of cardioversions and they did not work and still in A-fib. The ablation will burn the abnormal cells so only the SA node initiates the electrical impulse and thy are in normal sinus rhythm. I cannot say this enough, whether its acute or chronic A-fib they must take anticoagulants. They may be started on a heparin drip if it is acute to prevent clots from forming in atria until the PO anticoagulants are therapeutic, they will go home on either Coumadin, Eliquis or Xarelto. Make sure they are on them if they are in A-fib.



So the key points regarding atrial fibrillation are to understand the abnormal characteristics of this rhythm, the atria quiver and do not contract so there are no identifiable p waves on an EKG so it has a wavy baseline, the rhythm is irregular. These are the biggest characteristics of A-fib. Always assess your patients and determine if they are in RVR and control the heart rate so cardiac output is adequate. Monitor for signs and symptoms of strokes, we need to prevent strokes with atrial fibrillation make sure they are on some type of anticoagulant. Other treatment options would be medications beta blockers, calcium channel blockers, cardioversions and ablations.


I hope it that you guys have enjoyed this lesson and are more comfortable identifying atrial fibrillation on an EKG and understanding the nursing interventions to prevent complications. Make sure you check out all of the resources attached to this lesson. Now, go out and be your best self today! And, as always, happy nursing!