Sinus Bradycardia (Nursing)

00:01 Welcome to our video series on electrocardiogram.

00:04 I like to think of this one is the slow dance or couple skate of ECGs.

00:10 We're going to take a look at sinus brady.

00:13 Now at this point, we all know this is a normal ECG.

00:17 But if we do this, would you consider it to be abnormal? What if I tell you it belongs to this guy.

00:24 So taking this into account, should we consider this a good or a bad thing? Well, let's find out together in this course.

00:33 We've got the seven steps of how to analyze any strip.

00:37 We're not going to go into detail on those here because we do in our other videos. But there they are.

00:42 If this is one of your first videos to watch with us, you want to pause the video, walk through each one of the seven steps, and make sure you know what that means and how you would do that.

00:54 Otherwise, the rest of this video may be a little bit of a struggle for you.

00:59 Once again, let's recap.

01:01 Remember, the electrical impulse travels from the atria to the ventricles and its trajectory is what gets documented on the ECG strip.

01:10 At first, the electrical impulse gets created in the SA node and starts traveling toward the AV node.

01:17 This causes contraction of the musculature of the atria and the formation of the P wave.

01:23 Now, when the impulse reaches the AV node, it doesn't just pass through it. It gets delayed.

01:29 This delay is documented in the ECG strip as the PR segment.

01:34 So the PR segment corresponds to the passage of the impulse through the AV node.

01:40 Next, we have the QRS complex.

01:43 The QRS complex represents ventricular contraction, which is caused by the migration of the impulse from the AV node to the Purkinje fibers.

01:53 Moving on, we can see the T wave which is caused by repolarization or relaxation of the ventricles.

02:00 And as previously mentioned, the interval between the ventricular depolarization and repolarization gets documented as the ST segment.

02:10 Finally, we have the U wave, which is believed to be the product of a delayed repolarization of the Purkinje fibers.

02:17 And remember, this wave may or may not be present on the ECG strip.

02:23 So a normal P wave is the atrial contraction precedes every QRS complex in sinus brady.

02:31 The rhythm is regular but can vary slightly during respirations in any sinus rhythm.

02:37 The rate ranges between 60 and 100 for normal sinus rhythm.

02:43 The P wave is positive in Lead I, Lead II that you're looking at here, and the biphasic in lead V1.

02:53 Now, on these seven steps, we're going to walk through this strip.

02:57 So I want you to assess the heart rate and rhythm.

03:01 Remember, find a six second section of the strip, count the number of QRS complexes, and you want to multiply that by 10.

03:11 So use this strip as an exercise and match your answer to the one you see on the screen.

03:20 Now let's look at the P waves.

03:22 Are they all there? Do we have one P wave for every QRS? We do.

03:28 Do the P waves all look the same? They do. Excellent.

03:34 So, measure the PR interval next. We have a P wave for every QRS.

03:40 So you're going to want to measure that PR interval to make sure it's within the normal range.

03:44 Now, normal range for PR is 0.12 to 0.20 seconds, or 3 to 5 small squares on an ECG paper.

03:54 So what is the PR interval on this strip? Take the time to measure it using the small boxes and compare your answer with the answer you see on the screen.

04:05 Step four. Measure the QRS duration.

04:09 Now, less than 0.12 seconds or three small squares is considered normal.

04:15 Pause the video, measure the QRS duration on this strip and compare your answer with the one that will display.

04:25 Step five. Examine the ST segment.

04:28 Make sure there is no depression or elevation.

04:32 Is there any depression or elevation on this strip? Now, compare your answer to the one that we display.

04:41 Now, let's do step six. Take a look at the T wave.

04:45 In order for them to be normal, you want them rounded and not peaked or tall.

04:51 Number seven, measure the QT interval.

04:54 And we want it to be less than 0.46 in women, less than 0.45 in men.

05:00 So let's wrap up this section on sinus bradycardia.

05:04 The heart rate will be less than 60. The rhythm will be regular.

05:09 The P wave will be for each QRS and be identical.

05:12 Now, the PR interval will be 0.12 to 0.20.

05:17 And the QRS will be less than 0.12.

05:21 Now, let's go back to that patient we talked about in the beginning.

05:25 Remember the marathoner? Well, if this was his rhythm strip, would I be alarmed? No. Most likely I would not.

05:34 Because he's awake, alert. He's talking to me.

05:36 And I would always check a blood pressure.

05:39 If his blood pressure is normal for him, it's right along with a trend that he normally runs.

05:45 He has no complaints of dizziness or weakness.

05:48 He's doing fine. He's just incredibly fit.

05:52 He has excellent cardiovascular health.

05:56 However, if I take a 64-year-old and they're telling me they're dizzy, and they're weak, and they feel lightheaded, they have this rhythm, and they have a low blood pressure with this.

06:07 we would consider them symptomatic.

06:10 And they're going to need some type of treatment.

06:12 So marathoner, who's fine, blood pressure stable, awake, alert and oriented, no complaints.

06:18 We'll let you go right along with this sinus bradycardia.

06:22 Not a problem.

06:24 But for our older client, or any client that tells you they feel dizzy, they feel weak, they feel lightheaded, and their blood pressure is low, they are the ones we're going to pursue treatment for.

06:35 We consider them symptomatic.

06:38 Thank you for watching our video series today.