 Hi, welcome to Nursing School Explained. This video goes into atrial rhythms and specifically into atrial fibrillation. If you haven't already done so, I highly recommend watching my other videos that explain the basic electrophysiology and go into EKG interpretation basics such as how to use the EKG paper, determine the heart rate as well as know the normal intervals and rules to memorize for EKG interpretation so that you can apply them to every rhythm strip that you look at and hopefully get the right interpretation of that rhythm. So atrial fibrillation, also known as AFib, is a pretty common arrhythmia and what we're dealing with are multiple irritable foci in the atria. Remember that every cardiac cell has the property to initiate an impulse and for whatever reason now we have multiple focuses or foci that are irritable in the atria. So they try to take over as the pacemaker of the heart over the SA node. And atrial fibrillation can be acute which means the onset happened less than 48 hours ago. It can be paroxysmal meaning intermittent or it can be chronic lasting longer than one month which also puts the patient at high risk for stroke. You might already know that, so please watch my video on stroke that goes into the details of that. Now in atrial fibrillation the ventricular response can be less than 100 which would make the atrial fibrillation controlled or if it's greater than 100 that would make the atrial fibrillation uncontrolled. Looking at the details here and the principles of EKG rhythm interpretation and the rules we always start by looking at the rate here first. So the rate you can already see we don't have a clearly defined P wave that we are used to seeing we just have these squiggly lines right here in front of or in between these QRS complexes. It's really even hard to determine is this a T wave or is this already a P wave it's very hard to see. And the atrial fibrillation typically the atrial rate is between 4 to 600. The ventricular rate is variable in our case here we have 1 2 3 4 5 6 7 8 9 10 QRS complexes so our rate would be 100 and I know that on the previous slide it said less than 100 is controlled and above it is uncontrolled so in this case I will still call this controlled because 100 is right on the borderline. And then for rhythm regularity point number two it's there's this very distinct characterization called it is irregularly irregular meaning that there is no clear rhyme or reason to this it is just irregular every single QRS has a different distance from the previous one. There might be some similarities here but if we would measure this with calipers these distances what would measure them march them out with the EKG manual EKG drawing method we would basically determine that this is irregularly irregular saying that there's absolutely no shape or form behind this rhythm. Now the P waves in atrial fibrillation they are non identifiable because that we have these fibrillation kind of waves due to these multiple irritable cells in the atria that we can't really identify the P waves and certainly we know that there is more than one P wave for every QRS in these squiggly lines here. Now because looking at number four because the P waves are not really identifiable we can't really measure the PR interval and then the QRS is usually less than 0.10 or 0.12 which would be a normal QRS and so we can look at this here let's find a QRS that starts at a one of the thicker box lines so that would be one two maybe 0.08 for our QRS which makes the QRS normal. Here is another look at this atrial fibrillation again the characterizing factor is the squiggly lines and very irregularly irregular so absolutely no pattern to this rhythm here at all we can't really count the P waves we can't really distinguish the PRI but we know the QRS are normal in length less than 0.12 seconds. Causes for atrial fibrillation are coronary artery disease as well as hypertension or valve disorders such as regurgitations or insufficiencies, congestive heart failure, pulmonary embolus, hypoxia, alcohol and illegal substance intoxication as well as any underlying pulmonary disease such as pulmonary fibrosis, any kind of lung cancer and so forth. Hyperthyroidism also is a disorder where everything speeds up and then the heart can get irritable leading to atrial fibrillation and we know that potassium is very important and can lead to certain dysrhythmias so hypokalemia especially puts the patient at higher risk for atrial fibrillation. Science and symptoms will depend on the rate and duration so if the patient's heart rate is controlled meaning that the ventricular rate is less than 100 the patient most likely will have less symptoms than if it's uncontrolled let's say a rate of 160 that'll be much different and mostly if it's uncontrolled the patient will have more severe symptoms meaning they'll be dizzy or lightheaded they might complain of shortness of breath or anxiety they might faint have a syncopal event complaint of palpitations or feeling like the heart is racing in their chest as well as complain of chest pain or pressure and again in advanced dysrhythmias we have to distinguish between stable and asymptomatic patients as well as symptomatic and unstable patients so if the patient is stable and doesn't have any symptoms we can attempt a vagal maneuver just like in atrial fibrillation atrial flutter and atrial fibrillation are very similar here if we encourage the patient to perform a vagal maneuver by either bearing down or blowing through a straw it increases the pressure in the intrathoracic cavity and stimulates the vagus nerve which is in charge of the parasympathetic nervous system knowing that the parasympathetic nervous system slows everything down we're hoping that by the patient performing this vagal maneuver they will slow down their heart rate and maybe convert back to normal sinus rhythm medications that can be used in atrial fibrillation are any that cause the myocardium to be less irritable or slow down the heart rate very commonly we use calcium channel blockers it's probably the most commonly used medications for atrial fibrillation but beta blockers as well as the joxin and antirhythmics are also common but if the patient is symptomatic or unstable and the definition of unstable usually means that the patient has a change in level of consciousness or is hypotensive then we need to follow acls protocols and that means that the patient may need synchronized cardioversion of course if we find out the patient's atrial fibrillation is due to hypokalemia then we'll certainly need to treat that underlying cause and replenish the the potassium most likely intravenously here are some references and the rhythm strips with good websites that you can refer to also for more practice of restrips and here are my other videos in the ekg interpretation playlist specifically the atrial rhythms also where i'm discussing premature atrial contractions as well as atrial flutter and supraventricular tachycardia thanks for watching nursing school explained please subscribe to my channel give me a thumbs up and i will see you soon