point-of-care ultrasound. This is, so I, in my disclosure is that I'm the chair of the ultrasound committee here at SCCM, so this is something that I believe deeply in and I use in my daily practice, and I think it's really important, and I think that the use of point-of-care ultrasound is definitely increasing, and you're probably going to see maybe a little bit more questions on that as the exams unfold in the future. So a 55-year-old male with a history of IV drug use is hospitalized in the ICU for septic shock. Blood cultures grow staph aureus. On hospital day two, he developed severe hypoxia and is emergently intubated. Lung ultrasound is performed prior to intubation. Based on the imaging, what is the most likely cause of respiratory failure? Is it a pneumothorax? Is it a PE? Is it pulmonary edema? Or is it a mucus plug? So here's our imaging. It's a real case. Okay. So who's going to go with the pneumothorax? No one. Okay. Who's going to go with the PE? Okay. Who's going to go with pulmonary edema? This is great. All right. And mucus plug. So I've used this question. This is a patient that I was part of this case. And it's a question that I've actually used over probably the last six years. And no one knew it. And now everyone knows it. So it really kind of shows how lung ultrasound is becoming much more a part of our practice. And of course, there's bilateral diffuse B-lines, right? So there's interstitial alveolar syndrome that's going on here. There's fluid in the lungs. And we see that no matter where I put the probe, I had B-lines, right? There is lung sliding. There is not a pneumothorax because you see B-lines, right? So the two pleural layers have to be opposed in this setting. And there's just fluid everywhere. And for those of you that saw this little part that I tried to cover up, this person had bacteremia and then had endocarditis and then blew their mitral valve and went into pulmonary edema on the floor. And so got intubated in the setting of that. There's the chest X-ray. So key ultrasound findings for lung ultrasound. I think about it in three steps. The first step is I look at the pleural line. Is there normal lung sliding? That's just the first thing to look at, the absolute first thing you do when you put the probe on the chest. Is there lung sliding or not? If there's no lung sliding, that's going to take you down a differential diagnosis. If the pleural line is irregular and thickened and nodular, that also can tell you something about what you see with the next step. And the next step is your aeration pattern. The aeration pattern of the lungs, that's your parenchymal exam. You should see nothing, right? Because ultrasound is attenuated in dry lungs because there's air, right? So you don't get the ultrasound waves coming back to you. It attenuates. It's just darkness. And that is artifact. If the lung is abnormally aerated, right, so it is dense, the lung is dense, you get artifacts called B-lines, right? If it's really dense and consolidated down on itself and you can actually see the lung, then you can see the lung. That's a consolidation. And then finally, we look at the pleural space. You should see nothing. If you see, if there's an anechoic space that's there, right? So no echoes. Anechoic, no echoes. Dark space, that's going to be fluid. And then when there's fluid, you get compression atelectasis and then you get your consolidation. So normal up here, right? There's your pleural line. And there's motion there. This is with a phased array, so just your echoprobe, right? Your typical echoprobe. You can use a linear array too. There's your A-line, which is a reverberation of the pleural line. Everything below the pleural line is artifact. It's not actually there. It's just artifact. The only thing you can see is the pleural line and then the tissue above that. Here's your pleural line here. Here are your B-lines. These are those vertical ring down artifacts. They ring down from the pleural line. They move with pleural sliding. And they just tell you that there's increased lung density. There's abnormal aeration wherever you're putting the probe. And that is either due to fluid, which can be extravascular or cardiogenic. It can be due to inflammation, right? You're an ARDS patient, or there was this thing called COVID that happened. I don't know if you guys heard about it, but we saw a lot of B-lines. And then there was fibrosis, right, that will occur as well. The nice thing about B-lines is that the number of B-lines increase when there is in the setting of decreased aeration, right? So as you become more and more abnormally aerated, you get more and more B-lines until you get to that COVID place, right, where there's just whiteout. And then once you have consolidation, right, so there's literally almost no aeration in the lung, then you can actually see the lung itself, and that's a consolidation. We use this. I use it in cardiology because I monitor in patients in heart failure, right? So I do a quick exam, four zones on each side, and I look to see how we remove B-lines with diuretic over time. That's how I think about diuresis. I don't just use IVC. I sort of use both of those. To think about a patient presenting with dyspnea, right, so what is the cause? Again, I always focus on lung sliding first. If there is lung sliding, right, and there are no B-lines, then these are patients with normally aerated lungs who are short of breath. So you think about something like, for example, asthma or a PE. That's a classic one. Shortness of breath, clear lung zones with ultrasound, and they're hypoxic, then think about a PE. If they don't have lung sliding, then, and there are other findings, we can think about a pneumothorax. And then if there are B-lines, then is it a diffuse process, so is it across the chest or is it focal? If it's across the chest, then I'm thinking about cardiogenic pulmonary edema. If the pleural line is thin, if I do an echo at the same time and I see that there's dilated IVC, for example, or other markers of increased filling pressure. If you have diffuse B-lines, they're bilateral, but they're patchy in nature, the pleural line is thickened, it's kind of cobblestone, then you're thinking about, for example, ARDS. And we saw, I think everyone is like, just understands lung ultrasound much better now based on, again, COVID, because we used a lot of it. This is what it looks like, and this is sort of the way I teach it to the cardiologist, with the idea being that a patient with a bilateral interstitial process with effusions, that's more likely to be pulmonary edema. So I put the probe, I'm just looking at the chest, here, here, here, here, here, I see B-lines kind of everywhere. I may not see B-lines over the left side right here because the heart is there, and I see bilateral effusions. This person has wet lungs, right, when you're going to diurese them. If the person is short of breath and I only see B-lines in one place, right, just right here, then that's a focal process, right? That could be like a pneumonia, for example. And then I use other things, for example, filling pressures. I look at the IVC, stuff like that, to be able to sort of guide me in one direction or the other. Okay, case two, 50-year-old male is admitted to the CICU after suffering an out-of-hospital cardiac arrest. He underwent 65 minutes of ACLS before sustained return of spontaneous circulation in the ED. He's acidotic in shock, requiring high-dose vasopressors, and they put a dirty, right internal jugular line in during resuscitation. The fellow performs a lung ultrasound up in the CICU when they get up there. Based on the available images, what is the next best step? So urgent portable chest X-ray, replace the internal jugular line, chest tube thoracotomy, or again, we'll talk to vascular surgery. So ACLS for shock, lines put in, patient comes up to your unit, and now you're doing a lung ultrasound. What is the next step? Oh, no, don't go that direction. Okay, there. Let's go back one, see if it'll work. Okay, there we go. So what do people see? What would you do? Chest tube, right? Yeah, so we're seeing, again, like the only, so we're seeing lung sliding here. Again, sorry, but these are my images, but lung sliding on this side, and there's the pleural line. We have reverberation artifacts of the pleural line, the A lines, but there's no lung sliding, right? So it's going to be a pneumothorax. And there was a pneumothorax. And we'll go over. Oh, there it is. So yeah, absence of lung sliding, right? We have our pleural line, our A lines on that side. We just had, the only motion there is my hand kind of twitching, I guess, unfortunately. And there's our chest x-ray. There's the pneumothoraxes there. And again, so we'll talk a little bit about that pleural line. We kind of went through this differential. Probably should have done that case first, but here's normal again. So that's our pleural line. Everything below it is artifact. And here we have a pleural line there, but there's no motion. There's just the A lines. And this was a post-cardiac surgical patient. So when there's no pleural motion, no lung sliding, there is a differential. It doesn't mean it's a pneumothorax, right? It doesn't mean it. It just means that the two pleural layers, the visceral and parietal pleura are not against each other. Or a classic thing in your post-cardiac surgical patients is that they have inflammation and you won't see lung sliding, right? So they don't necessarily always have a pneumothorax in that setting. You won't see lung sliding. And then bad COPD patients with a lot of bola, they may not have lung sliding either. So a more definitive way to think about lung sliding, again, if you have some difficulty seeing it, this is with a linear array, right? Your linear array you're going to use for vascular access. And we can see just a much better, it's higher frequency, so we can see the pleural sliding quite well. Here we don't. And then you can use M mode. M mode shows motion. So those bar lines, the lines up there, it looks like a barcode. That's just those layers of the tissue above the pleural line where there's no motion. When the motion starts, we see the granular picture there. And here, again, everything looks the same, right? It's kind of the barcode sign or stratosphere sign, but there's no motion that's there. And that's our pleural line. And then the pathognomonic finding is what's called a lung point. A lung point is you can actually see where the pneumothorax is and the normal lung move into view as a person takes a breath in, right, and the lung comes up. So that's a lung point. We can see it here, too. There's lung sliding, and then it drifts away. And this is what you'll see. You'll see some lung sliding, and then it'll be gone. So that's a lung point. That's pathognomonic. Specificity is 100% if you believe the studies. And here, so diagnosis of pneumothorax, I think this is why it's important. We could be a test question, is that it's a more sensitive modality for picking up a pneumothorax compared to chest X-ray, but they're both specific, right? So the finding's there. It's there on chest X-ray. If it's not, it doesn't mean it's not there. Okay, so I think this is our last case. 62-year-old male successfully resuscitated in the ED after presenting with an out-of-hospital cardiac arrest, likely secondary to opioid overdose. Upon presentation to the ICU, he is hypotensive. Based on the following ultrasound images, what is the next best step? So based on the ultrasound images, are you going to defibrillate the patient, are you going to transfuse the patient, are you going to do a pericardiosynthesis, or are you going to stick a needle into the patient? Here's your images. Okay, everyone got enough here? Kind of see what's going on? So who is going to do a pericardiosynthesis? Hypotensive patient post-cardiac arrest? Okay. Who is going to do a neothoracostomy? Who is going to transfuse the patient? Couple people, right? So what do we have here? So we have, this is what's called an extended FAST exam. But where we incorporate a lung exam, a subcostal view, and then we have like sort of typical like FAST, right? So the lung exam shows B-lines. See a couple of them, right? Couple of B-lines here and there. And lung sliding. If you see a B-line, there's not a pneumothorax. Quick way to say there's not a pneumothorax, right? If there's a B-line present, the two layers of the pleura are opposed and there's not a pneumothorax. So there is a pneumothorax here. This is the left ventricle and the right ventricle. There is a tiny pericardial effusion, but the LV looks underfilled and hyperdynamic, right? So I think the intravascular volume is gonna be low. And the intravascular volume is low because the person is bleeding, right? So this is a positive FAST finding here. This is fluid around the kidney on the right side. So this person is bleeding. So I think the right thing to do here is to transfuse the patient. And definitely like I have incorporated a FAST exam into my cardiac arrest management because for a lot of reasons, I definitely have had several patients. This actually is a patient that bled when the Lucas device was just a little low and they had a intrahepatic artery bleed. And so we took that patient to IR. But the eFAST exam, I wanted to include this because it kind of goes over a lot of the different ultrasound stuff that you can see. But again, it includes the lung ultrasound for pneumothorax, pericardial fluid, and then you do your typical right upper quadrant, left upper quadrant, and pelvic imaging for pleural or interperitoneal fluid. One of the test questions could be if your FAST exam is, if someone has a classic test question that I've seen is someone has penetrating trauma and they wanna like stop to do an exam or stop, the patient goes to the OR, right? So the FAST doesn't have to be a part of that. So that's a key thing. The other thing is that your FAST exam, the sensitivity improves over time, right? So you need to repeat the study if you don't see fluid at the very beginning. And then these are the places where you see the fluid, right, you have your Morsen's pouch, the inferior pole of the kidney, subdiaphragmatic, and on the other side, the subdiaphragmatic, the spinal renal recess, and the inferior pole of the kidney. Okay. Oh, it didn't play. We got it to play the last time. I don't know what happened. But I wanted to finish just because the other thing you could see is a pericardial effusion. If you were to get a test question, pericardial effusion, you know it's a pericardial effusion because the fluid is anterior to the descending aorta, right, so the fluid comes up anterior to that. It's a pericardial effusion. If it's a pleural effusion, it's posterior. So your descending aorta, that is your anatomic landmark to know if it's pleural or pericardial. And that's why in ECHOES, if you guys ever start looking at ECHOES, the first view every ECHOLAB usually does is actually a zoomed out view where we see way behind the left ventricle. And we're doing that because we're looking for a pleural effusion. So we wanna look for the pleural effusion and then we zoom up to look at the heart. And again, this is gonna be, this is tamponade. If you look there, there's early diastolic collapse of the right ventricle. You know it's diastolic because it's happening when the mitral valve is open. If I was to slow that down and time it, the mitral valve is open, that's diastole, the RV collapses. RV collapses because that's the lowest pressure in the right ventricle is early diastole. And tamponade is when there's increased interpericardial pressure. So the pressure in the pericardium is increased, usually due to fluid, right? You don't need a ton of fluid to do that. The pericardium is a stiff sac, it's fibrous. So if I was to bleed quickly into my pericardium, it wouldn't take a lot of fluid for me to go into tamponade. If you're a dialysis patient, and you've been putting fluid into your pericardium over the last six months, you can show up with a massive pleural effusion and not have a lot of hemodynamic consequence. Until, of course, you dialyze seven liters off that person in two days, and then they do manifest tamponade. And this is, I think, the last, please don't have a seizure with that. This is the last slide. So the way to think about tamponade, just to be a test question, swinging heart, stick a needle in, that's tamponade. RV, diastolic collapse, that is the most specific finding, right? The most specific finding. RV, RA, chamber collapse is very sensitive, but not specific, because the RA can, with an atrial contraction, will actually bow in, right? Dilated IVC is very sensitive. You have to have a dilated IVC to have tamponade, you have to have a high CVP, and then there's other findings, and I'll end there. I think I'm on time. Okay, thank you very much.

POCUS

critical care

lung ultrasound

pulmonary edema

pneumothorax