Understanding when to use echo in point-of-care ultrasound (POCUS)
Understand when to do a bedside echo and what's up with the so-called marker controversy.
Echo helps to fill in gaps when there is a gaping hole in your diagnostic picture. This short case study from our Point-of-Care Ultrasound (POCUS) Essentials course will demonstrate the utility of using echo when bloodwork and ECG traces don't tell the whole story, and teach you the four views that must be used in every patient.
This video was taken from our POCUS Essentials course taught by Viveta Lobo, MD who is an attending emergency medicine physician and Associate Director, Emergency Ultrasound Fellowship at Stanford University Medical Center in California, USA.
[00:00:00] Let's begin with a case. You have a 55-year-old male who presents with shortness of breath. Initial exam, you noticed some wheezing bilaterally on his lower lung bases, his vital signs are about normal. So, you start to think about your initial assessment plan. You may consider ordering some blood work, maybe get a chest x-ray, an EKG. And you think about your differential diagnosis, perhaps he has pneumonia, a pulmonary embolus,
[00:00:30] acute coronary syndrome, heart failure, pericardial effusion, just to name a few. So, here is your data. A quick look and you can probably tell that there aren't any concerning abnormalities on his lab work. Here's his EKG. You'll notice he’s in normal sinus rhythm, doesn't have any acute concerning changes. Here's his chest x-ray. No signs of pulmonary congestion, no infiltrates, no pleural effusions, looks pretty normal.
[00:01:00] So, what are you going to do now? We really don't have a good understanding of what his pathological process is yet. What if I could offer some additional information? What if you could actually assess his cardiac function at this point, would that be helpful? Probably, right? So, let's say, you know how to perform an echo, you go ahead and do a point-of-care echo at the bedside. You find out that he's got some reduced left ventricular contractility, he's got normal chamber sizes, and he has no pericardial
[00:01:30] effusion. Putting this information together with your clinical assessment and evaluation, you'd probably be more concerned now that this is some sort of new cardiac injury, causing a new onset congestive heart failure picture. So, what is your focused question with a bedside ultrasound echo exam? Well, your focused question is very simple. There are three things you're going to assess for on your point-of-care echo: contractility, pericardial effusion, and chamber
[00:02:00] sizes. When performing your point-of-care echo, you're going to obtain four basic views, a parasternal long-axis view, a parasternal short-axis view, an apical view, and a subxiphoid view. Now a question I get all the time is—do I really need to perform all four views on every patient? The answer is, yes. You always want to get multiple views to assess for your data points. This will confirm or rule out your findings.
[00:02:30] Also, some views are better than others for assessing one or more of your data points. So, always attempt all four views on all your patients. Now, I have to bring this up. There is some marker controversy. Where should the dot go on the screen? You're probably used to seeing cardiology echo's, where they will traditionally place the indicator to the right of the screen. However, point-of-care ultrasound is not just echo's but extends to other
[00:03:00] organ systems, which traditionally have the indicator to the left of the screen. When we do our echo's, we continue to keep the indicator to the left of the screen. But to accommodate for that, we will rotate our probe indicator 180 degrees to obtain our images. This will produce the same image orientation on your screen as our cardiology colleagues, so we all keep it very consistent.