Good afternoon everybody. Thank you for coming today. Thank you for the organizers for the invitation. And this is just a call for anybody that wants to be part of the respiratory care committee here at the SECM. Please come in. We need more members because this is a pretty important topic that I'm going to be talking about. So I have control here. I do have some disclosures. I talk a lot about mechanical ventilation and I don't endorse any company. I love ventilators. All of them are healthy and good. And so whatever I say, it's my opinion today. I do receive some fees for books, chapters, lectures and whatnot, but nothing necessarily related to this topic. So in 2019, we did a review of the literature of what had happened and had been written. And when we did that review, after we finished, we realized that there were so many names coming out for the same things. How could we interact and live together and communicate and know how to treat things when we name things different things and they are exactly the same? So there is no universal classification. This is actually a call to action because we need to sit down and actually as a society, as a critical care society and multiple societies get together and start naming things as they should. There is regional differences. For example, if you go to Spain, cycling is the start of the breath. In the U.S., it's the end of the breath. Now if you're reading an article from Spain, you see one of the challenges. There is misnomers. For example, the term flow asynchrony. Synchrony refers to time. And so we're not talking about the timing of the flow. We're talking about the magnitude of the flow that the patient receives. Auto trigger, it's not the machine triggering on its own. It's something else triggering. So we use the word auto. I mean, if you go to the etymology of these words, we are making a mess out of them. Same thing, different stuff. Cycle delay, cycle off, asynchrony. We use all of them. So we sat down and we said, okay, let's grab the dictionary, sit down and put things in order. And this is where we ended. That's the QR code for the article that we published last year. And essentially we talked that when you talk about patient-ventilator interactions, you either base them on timing, which talks about synchrony, or you talk about work of breathing, which is the magnitude, the work that is being done by the ventilator and the work being done by the patient. That's what we're doing in physics and by the definition that actually Eric very appropriately talked about. We talk about trigger, the magnitude of the breath, then the cycle of the breath. So that's what we're going to do today. Now, this one has a pulse system, and I'm going to give you time when it comes to reviewing some of them. Now, one of the items that is also pretty confusing in the literature is what is the reference? So now we have catheters that we can put in the esophagus that can measure the electrical activity of the diaphragm. We can put an esophageal balloon and we can measure the deflection of the esophageal pressure, or we can see the waveforms and read them. Most of the time we use the waveforms to read the interaction. But if you have an esophageal catheter, that's the truth. If you have an electrical activity of the diaphragm, that's the truth. However, there's confusion because actually there's a condition called electromechanical dissociation in which you're going to have the electrical activity still going on and no movement from the muscle. But that's for more thought in how we are going to start classifying stuff out there. So in terms of work, this one needs a lot of love. In practice, all of you know how to detect under-assistance. You walk in, the patient is using accessory muscles, retraction, paradox, working hard, deflections on the airways. But we have not put much attention into over-assistance when we give too much support. Because why? You walk back in the ventilator and the patient looks fantastic, right? That's actually what we did in sedation and paralysis, and the patient looks the best waveforms ever. That's a QR for a beautiful article written from Toronto by Irene Tellez and Lorraine Brochard that talks about this concept that I think that us as a community should be reviewing. And then Eric brought up the concept of work-shifting. And this just means that when you have the activity of the patient and the ventilator at the same time, some of the work is going to interact between the patient and the ventilator. And actually, this graph that I'm going to show should be ingraining your brain. In the y-axis, you have ventilator work of breathing, or the pressure that the ventilator delivers. On the x-axis is the patient work of breathing. From zero, nothing, paralyzed, all the way to very high, the highest effort you can imagine. And the mode of mechanical ventilation and that relationship between those two, depending on the mode that you're going to put them. So if you put a patient on volume control, as the patient does more effort, as the patient does more effort, the ventilator delivers less pressure. So many of you here have heard, I'm going to arrest the patient. And what mode do they put them on? Volume control. Look at the relationship. Now that may be, if you put enough volume, that may be gone. So this is just so that you start putting this mental framework of how we read this. Now, all of you in RT school, med school, nursing school, they taught you how to read an EKG. Who taught us how to read patient-ventilator interactions with a method? None, right? Little tear on both eyes coming down. So the same way that Eric talked about the pressure, the breath delivery, that's the order. You start with the trigger, inspiration, the cycle, expiration. So let's practice. So here it is. Now I'm going to, I want you to look at the waveform, all right? You have several items on this waveform. On top you have the pressure. Then you have this little gray waveform on top of the yellow waveform. That's the electrical activity of the diaphragm. And below you have the flow waveform. And so your trigger can be normal. It can be early, meaning the ventilator triggered first, and then the patient. It can be late, the patient triggered first, and then the machine took a while to activate. It can be failed, meaning that the patient tried and didn't get it. It can be false, meaning that the machine is triggering thinking that you are doing it, all right? So look at this. Choose your option. You may have more than one, but choose your option, all right? And we're going to move, grab your high-quality phones. Hopefully you have good connection. And then on the top you can see polev.com slash critical care 2. I didn't put it like that. That's how it came out. So just put that address and vote. And after this, all of them is going to be the same. You just have to type it once. I love how it moves, it oscillates with reality. All right, so it seems that majority of you thought that this was late, so let's analyze it together. Well, it keeps moving. So I don't know if people are migrating to late afterwards, but let's see. Can we move it forward, because it's not loving, there you go. So there's two actually, so for those of you that chose. So I put them in, there's no mouse. But in the blue square, you can see that the electrical activity of the diaphragm started way before. Actually, even way before the deflection on the pressure waveform. You see how the pressure waveform goes really down, and then the ventilator pressurizes? So there's things that your eyes cannot see because we're not monitoring, and the waveform may not show it. Although the flow waveform does show that there's an attempt to cross the baseline. And on the green box, you can see that actually how the gray line and the yellow line match. You see how pretty they are. So you have a normal breath, and then you have two good examples of a late, late trigger, all right? All right, very good. So we agree with that one, let's do the next one. All right, this one is true. This is a patient, you're walking by, and you look at this, all right? It's an actual live human being that gets this one. You can choose more than one, but make your selection, mental selection, and then we'll go to the next screen, all right? Is there a way to make my mouse a pointer? Okay, keep the shake, okay. All right, so we have an early trigger, we have a failed trigger, and we have a false trigger. So we have, those are the key items that appear. So let's take a look. Thank you. All right, so this one is a beautiful example of three, I call it triple trigger trouble, all right? On the orange box, what you see, and there is no mouse. Oh, there you go, hello. So let's start by the simple one. Let's start by the failed one. So the failed is the green box, and what you see here is the flow tries to cross the baseline, the pressure actually moves down, and there's no trigger delivered by the ventilator. So the ventilator failed, failed to deliver a breath. This is a bad, bad thing. A patient has a lot of issues if you see this. Then you see this one over here, in which you actually see the flow crosses over, the pressure is dropping, but it takes a while for the patient to activate. So that's a late trigger. And that's also a manifestation in this case of a patient with severe, severe otopip. And the orange one, this is a tricky one because you see the flow and the flow reaches zero. There's no evidence of effort from the patient. The flow is reaching zero and then suddenly the patient excels and it crosses over and a breath is delivered and you don't see any evidence of effort. Actually, there's no flow. This is a thing that happens in certain ventilators when there's recoil, recoil after there's very high pressure and you get an extra breath. That type of double trigger that you would see is because of a false, false trigger. There is no evidence of PMOS. There's no cardiac oscillations. There's no secretions. It's just the ventilator was trying to maintain the pressure where it should and you get an extra breath. Fair? Okay, next. Alrighty, now we move to cycle. We're gonna go to work in a second. So this cycle can only be normal, early, or late. And on the top you have the pressure and on the bottom you have flow. All right? So what do you think? Is this normal, early, or late? A lot of normals, lots of love for the cycle. Excellent. And some that think that this is early. All right, let's take a look. Can you press the high quality button that moves me forward? Excuse me. Thank you. All right, so this is early. Now, let's analyze it a little bit. So you have the trigger, the breath trigger. You see the breath is here. There's the flow. And the flow continues to go. And then you see, instead of that beautiful decay, there should be a peak here, and then an exponential decay. And instead of that, you see how the flow tries to go all the way to the top. That's a manifestation that the patient was still inhaling. And so we shot the breath early. You get, that's an early cycle. And on the second one, it's not as marked. You can still see, actually, you see how much flow the patient is getting really high. But you see here an amputation. You don't see that peak expiratory flow that you should see. You see the flow amputated. It's became rounded. That's a manifestation of active PEMAS. So this is early cycle. All right, this is not that hard now. Because it can be either normal, early, or late. And this is a classic example, because you're going to walk by the unit, and you probably are seeing this much more often than you see. So what do you think it is? Normal, early, yes. So absolutely. So you see the evidence of, instead of the exponential decay that you should see during cycle, you see how it reaches. And then there is this flat portion. Actually, in some ventilators, you may even see it cross over as the patient is exhaling during inspiration. This is a classic manifestation of a late, late cycle. All righty, here's the graduation. So you can answer trigger or cycle. So take a look at this waveform. And I'll hurry up. And look at trigger or cycle. How's the trigger? Normal, early, late, failed, or false? And how's the cycle? All right. Mic. I'll go back. Can we go back, please? Thank you. And what you have here, just for those that are seeing this waveform and saying, que pasa? This is actually an esophageal pressure. So when you, you can do this by looking at the waveforms up here or looking at the esophageal pressure. And then we put this little line here for you to see a little bit better where the breath actually ends. All right. It's like a living organism. All righty, let's... Very good. So many of you caught this. So you have what we call an early trigger. So you will recognize this because you see here the patient effort. Here's where the patient started the effort. This is where it ended. You can see that the ventilator triggered the breath and then it came the action from the patient. This is what in the literature right now many are calling reverse trigger. We call it early because there's many other causes for this. Reverse talks about the specific mechanism, but that's what it talks. And we usually just talk about the first thing that happens because early trigger will cause other problems. So if you have one desynchrony, the first one is the one that causes the rest of them. So you just cure the first one, it will cure the rest of the desynchronies. If not, you were gonna try to be moving everything to fix the patient. And finally, work. And so if this is a patient on volume control, you have pressure, the flow and volume. And so is this normal? Is there severe work shifting or under assistance, over assistance? This is a showstopper. This is when you're walking in the unit, you see this and you... And you... So let's see what you all think. Yeah, I mean, this is a classic one. 86% of you recognize the problem. The pressure during the inspiration is going below the baseline. That's never, never good. And finally, this is an example just for the sake of time of over assistance. And what you see here is we have the electrical activity of the diaphragm. And essentially the patient triggers the breath, but after that, there's essentially no more activity of the patient than the ventilator is delivering all the support. So you can see how little is the peak of the electrical activity of the diaphragm. We don't know how to recognize this. There's a lot of research that needs to be done here. But I put this here for you to start thinking as you're walking in front of your patients, if the ventilator is doing all the work, is that what you want? So with this, we can move to the last one. I would just end by, we need to speak the same language to be able to understand each other. I will put that as a key. That's how you're understanding what I'm saying right now. This method is similar to reading an EKG and to the tech PBI. This is what we propose. And it works for us as a teaching tool. And what I would say is that regardless where we end after a complete society can sit down and put these names in order is that at this time, the patient ventilator interactions can only be assessed in terms of synchrony and that's trigger and cycle. And in terms of work of breathing, which is doing inspiration and expiration. Thank you very much. I hope you enjoyed.

consistent terminology

patient-ventilator interactions

respiratory care

universal classification

standardize terminology