So I have no financial disclosures. Today I'll be talking about the hitting diagnostic difficulties with ultrasound, the things that you don't know that you don't know, basically. So as we all know, ultrasound has really been very popular. The size of the probes becomes very small. Even the public are suggesting that using sound is old, and probably moving to ultrasound is the way to go. This was just published in The New Yorker just a few days ago. And we know that learning ultrasound is not that difficult. There's big variation in learning. You can do a course with the Society of Critical Care Medicine for a full two days, but you can go and do another course in some other workshop for three hours, and then you'll feel like you have a probe and you can use it. And that creates a big problem. Should be sound here. So this instructor thinks that he knows what he's doing, and then. Sorry. No, that's fine. So for this reason, the Joint Commission and the Emergency Care Research Institute placed ultrasound in the number two in the top 10 health technology hazard. And mainly because their concerns about the safeguards for using ultrasound is outpaced by the availability of the machines and the widespread of the use, and that there is not enough oversight that makes it safe. I like the I-AIM framework for POCUS. It's an acronym for the Indication, Acquisition, Interpretation, and Medical Decision Making. It's educational and medical clinical model for ultrasound use. So the indication is you shouldn't use the ultrasound unless you have a question, a burning question that you need to answer right now. Otherwise, don't use it. And then for the acquisition, it's basically how you will get the information that you need, what kind of use you want, what kind of probe you want to use, patient positioning. And then comes the DICE interpretation, where you need to look at the image quality first before you do the interpretation. You need to recognize the structures, and then you need to start picking on patterns. And then what do you do with the information you have? Whether you're ready to answer your question or do you need more help? And then this is the problem. Do you know that you need help when you need help? So this is an example. The most common indication for ultrasound is your patient is hypotensive. So then when you do the ultrasound, you try to rule out a couple of patterns, like the severe hypovolemia. You rule out pump failure or severe left ventricular dysfunction. You look for some patterns for obstructive physiology. And then if everything looks good, you claim the SVR. But the problem starts to arise when you have mixed kinds of shock, when you have underlying chronic disease. This starts to get complicated. There are rare kinds of shock that you don't see every day. Sometimes you have findings that you cannot explain. And there is sometimes lack of agreement between your study and the patients that you have. Sometimes you don't have the complete information. And that's a problem, because really you don't know what you don't know. So for this reason, I'm going to walk you through a couple of difficult cases that I encountered through the year. And I'm just going to, every case we did here is trying to answer one of these questions. Is my patient hypovolemic or not? Why is my patient hypotensive? Why is my patient hypoxic? And then cardiac arrest. See here. So for cardiac arrest, this also has sound. There's a cluck in the right side. It's pointing to a cluck in the right atrium. So in basically doing the ultrasound during cardiac arrest, you can actually see if the heart is moving at all, if there is organized cardiac motion. Or there is no organized cardiac motion. And there is organized cardiac motion. So here, this is true standstill, true PAA. We call this pseudo-PAA, where the ventricle is trying to generate stroke volume, but it's not enough to be felt. And the implication for this is if you have organized cardiac motion, then the prognosis is much better. You see here more than half of the patients who have cardiac motion out of hospital cardiac arrest series made it out of the, actually had a return of spontaneous circulation. And nine out of 378 patients made it. So this number is zero. That's why the American Heart Association in 2020's recommendation recommended that you should not look at the standstill on the heart to make a decision to stop your chest compressions. You need to really look at other factors. Especially these studies we saw was for out-of-hospital cardiac arrest would deal with in-hospital cardiac arrest, but the statistics are different. 10, nine, eight, seven, six, five, four, three, two, one. One of the simulation scenarios at our institution that we did our residency. Pulse check. Looking at our rhythm. Looks like a non-shockable rhythm. Do we have a pulse? How much time? We don't pulse. Countdown time, please. Five, four, three, two, one. Resuming chest compressions. Can you get a milligram of epinephrine, Darcy? Yes. Let's see your hand. Thank you. All right, guys. There's no sign of any pericardial fusion, so it's not cardiac tamponade. The right ventricle is small in size and hyperdynamic, so no increased risk for pulmonary embolus. It looks like we're underfilled. We need some volume, guys. OK. One milligram of epinephrine is fine. There's some surgical bleeding. This could be hemorrhagic shock. OK. We've got the surgery team on the way. We're getting pressure fluid. Those are good quality chest compressions. So after this case simulation, do you think the resident did well, or they didn't do well? They find what's going on. They ruled out PE, and they found the etiology. The only problem is they paused chest compressions for 17 seconds. This is not acceptable. Just how can I move to the next slide here? OK. OK, so basically, during cardiac arrest, when you apply the optimal chest compressions with a good depth and rate, you'll get perfusion. And then the moment you stop chest compressions, perfusion goes down to zero, and then it takes time to pick up again. For this reason, the American Heart Association recommended don't interrupt flow more than 10 seconds. And there are two studies in 2017 showed that when ultrasound is used during cardiac arrest, the pulse check was eight seconds longer than when the ultrasound is not used. And this was in all the studies that looked at, the residents or the physicians in the emergency room did not follow protocol. So that's why we teach our residents on utilizing a protocol, and we do simulation. And you can see here, we run them through five simulations every year. And this is their first simulation. This is actually done when I was a fellow at Hopkins. And you can see the no flow interval improves with simulation. So doing the ultrasound during cardiac arrest doesn't come without a risk. Is my patient hypovolemic or not? So I'm gonna share with you this case. This is basically someone who came for small bowel obstruction for X lab. He's having history of hypertension, had two liters of crystalloids, and he's hypotensive. So also, he has an NG tube and got 1.3 liters out. Plus, I don't know how much fluid he got before going to the OR. So this is the resident doing a transthoracic or a point of care in the OR. And as you see, the cavity is very small. So her diagnosis was this is basically hypovolemic shock. That's good fluid. The only problem is we noticed that the left ventricle's really thick. And this patient probably has severe dystolic dysfunction. So it's very important to recognize the preexisting disease when you do the ultrasound. And that affects your management. For instance, in this patient, normal patients will have good opening that utilizes ATP that sucks the blood in. And we can test that with echo by looking at the mitral inflow and look at the tissue Doppler, the movement here. And in dystolic dysfunction, which happens when the left ventricle function is normal, or sometimes the dystolic function is normal or abnormal, it doesn't matter. But dystolic dysfunction, you need to push that blood. You need to increase the preload. And you can support it with fluid. The only problem with that is you'll end up with elevated left ventricular pressure. And that will give you a risk for pulmonary edema, which you can identify by ultrasound. So in this situation, you need to shift your question. It's not is my patient hypovolemic or not? Your question should be is my patient volume responsive or not? And you can do this without doing an ultrasound. This patient is paralyzed with closed chest with sinus rhythm. We need to increase the tidal volume to more than eight cc's per kilogram, and then look for pulse pressure variation. And that will give us the answer. In this situation, the pulse pressure variation doesn't seem to be really big. We're looking for anything above 10 or 12% between the difference between maximum, minus minimum over the average, and gives you a volume responsive sign. So made the calculations, and it was 5%. So patient was not volume responsive. We went up on the phenylephrine. And here you can see the difference between volume responsive and not, even without the calculations. And then, is the patient fluid tolerant or not? By looking at the upper lungs, that gave us an indication. And also, we looked at the lungs at the end of the procedure, and we're able to extubate the patient knowing that we give the right amount of fluid. So the pressure was fine, and what about if your baseline ejection fraction is 30%, or less than 30%, and your patient is in shock? This patient was treated for cardiogenic shock. The resident did not look at the chart, didn't recognize that the patient has low ejection fraction to start with, and turned out that the patient was septic, was hypovolemic, and that was evident when they came back and did the ultrasound for the IVC, and the treatment was volume. So the baseline, not all the hearts are the same. The baseline play a big factor. What about the right heart? So this patient here has history of pneumonia, ARDS. I mean, he presented pneumonia, ARDS, and has history of COPD and sleep apnea. His pressure immediately before induction was 85 over 65. So we can see here, this is a sub-costal view. And this is the liver, and then this is a site, not pericardial fusion. Now, if I wanna look at the right ventricle, try to assess the right ventricle function, it's really difficult to get this from here, because you can get good assessment in extremes. You can see the RV, you can see if it's really normal or severely abnormal. In this situation, it's a gray zone. And that patient has a small IVC, so he was induced, not big dose of anesthetic, but he was giving very quickly one liter of fluid, and that led to severe hypotension after induction. So as much as we'd like to think that the right side and left side are connected all the time, but in pneumonia hypertension situations, you can give fluids, and you cannot pass it through to the left side, you'll end up with dilated RV with septal shift, and that cause obstructive shock. Now you can pick it up with a sub-costal view. Six minutes later, that patient actually got into cardiac arrest, and you can see here, the left ventricle is totally obliterated. So something you cannot really assess just by a quick ultrasound. In this situation, if you think your patient is hypovolemic and have RV dysfunction, the treatment to optimize cardiac output should be small boluses, not a liter bolus. Small boluses and reassessment. Okay, what about the inferior vena cava? Since I don't have a lot of time, I think Carla covered a lot of these things, but I'm gonna show you three examples. This patient has abdominal compartment syndrome, so even though the IVC is flat, but he's hypovolemic. And this patient, the IVC is collapsible because it wasn't CPAP, so the respiratory effort affect your collapsibility, and this patient has tamponade, so the treatment here is give more volume rather than diuresing him, despite this plethoric IVC. Also, some young athletes will have large IVC, larger than the average. Their average is three centimeters compared to one centimeter normal. Also, I found a problem differentiated between the aorta and the IVC. This is one of the AI-equipped ultrasound machines that I use to help train our residents. It basically detects the right view and take an image the moment it feels like it get the correct thing. The only thing is this was, even though this looks like a hepatic vein, this was actually an aorta. We were able to trick that machine over and over again to get it to capture the aorta as an IVC. We send the feedback to the company. So it's not really simple. Can we go to the next slide? That's why I tell my residents, always when you view your IVC, when you save it, save the next clip as the aorta. So this way I know for sure. Next slide. Next slide. Okay, so last week I was in Cambodia on a medical mission and I got this text. It was seven o'clock in the morning in Albany, but it was 7 p.m. in Cambodia and it was basically about a patient who really got severe hypotensive and PACU. He had a Plorix catheter placed in his liver instead of his lungs. And the resident claims that the IVC was full and the first question I got from the quality management officer is, do we save the images? And thankfully, yes we do. So here's the IVC. It looks really full. The subcostal view, I mean, I cannot comment on the left ventricular function, so I train my residents to always do an additional view to compare. And you can see here the base is very hyperdynamic, but the body and the apex is not. So this patient has some sort of probably tachysubo and I cannot believe the IVC at this point. It's distended, but it doesn't really tell about the volume status because this patient has systolic and diastolic dysfunction. So that was probably, was early on during the hemorrhagic shock that the patient got. And by saving the images, the resident saved himself from being like, hey, did you mistake the IVC for Awarta? Did you really do a good job capturing the images? Next. So our system in Albany Med, we actually, I encourage all the resident to save all the images. And it's not by words, but by making it simple. So all our ultrasound machines are equipped with this scanner. You scan yourself as the operator and scan the patients and you're done. That's all you need to do. And after that, next. The residents are instructed to obtain the images and not to try to do any interpretation during doing the images. I usually, during rounds, have them do a quick exam. I give them three minutes and 10 seconds and let them do as much as they can. So basically, they start with a subcostal view, then the IVC, they look at the Awarta to confirm. In many cases, they can look at the subcostal short axis view to take a quick look at the heart. No interpretation, just checking the images and then go to the lungs, whatever they can do in three minutes. And it's usually, we do this for every patient, usually for volume status. Next. Then outside the room, we interpret the images. We look at the quality and then we identify the structures. And this is usually supervised. And if, for instance, I'm not around or my colleague's not around, they still do go through the same process. And they fill a report and they save the images. Next. And then they give basically the report to the team when they get consulted. Hey, this is basically what happened, this is what we saw and this is how it's related. And then all images are saved. We used to, in 2015, take these images by a thumb drive and take it to a secure hard drive that's located in my office. So me and my colleague, who are both past the critical care echo boards, can review all the images and filter them. If the images was done with an indication and it's a good quality, we upload it to the PACS system so everybody can see it. If not, we keep it for educational use and also for backup. So for this, I'm just gonna go share another case very quickly, shows that things can get complicated. So this patient has a history of hypertension, got big doses of remifentanil and propofol for his surgery and his blood pressure went down quickly. That was before incision. The heart in general, this is a subcostal view, contractility doesn't look super superb. We thought it's related to the anesthetics. So the patient got epinephrine boluses and then the pressure went down and couldn't be restored. Next. So here, the IVC was plethoric, 2.12 centimeter with no changes, but also the ventricle was hyperdynamic. So this was a dilemma for the resident, he didn't know how to interpret it, but also he didn't notice that the left ventricle is thick. So we did the epical three chamber view and here you can see that there's a big turbulence in the left ventricle outflow track and this is a mitral regurge and there's dynamic LVOT obstruction. So the treatment, we placed a continuous Doppler and you can see here, there's acceleration of flow. So this was a case of SAM, dynamic LVOT obstruction, where the IVC was plethoric, but the treatment was volume resuscitation and afterload treatment with phenylephrine and stop all the inotropes, inotropes was not a good thing. And thanks Carla, basically covered a lot of the tamponade, but I would just wanna confirm, this patient looked like a tamponade, but has a flat IVC. Since I don't have time, I'll go through it very quickly. So she was very hypotensive, almost coding in the CCU and turned out that she was having bleeding. She had a cardiac cath and she had retroperitoneal bleed that she cannot pick up with ultrasound, but it was obvious from the outside. So the treatment here is volume. Another quick case here, which one is that? Oh, so patients who have, if you're trying to rule out tamponade in the post-cardiac surgery, you cannot do that with point-of-care ultrasound, it's out of scope. Because you might have a focal clot located in the posterior area that you need an ultrasound, trans-esophageal echo. So this is an example of calling for help. How am I doing time, done? Okay, so yeah, that's about it. Thanks for now.

ultrasound

diagnosing conditions

point-of-care ultrasound

I-AIM framework

image quality

interpretation