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Management of Impella Emergencies
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In this episode, Dr. Sergio Zanotti discusses emergency management and resuscitation of patients with left-sided Impella support. We will base our discussion on a recently published United Kingdom multisociety consensus statement. Our guests for this episode are two of the authors of this consensus statement.
Dr. Zanotti is joined by Dr. Waqas Akhtar, a consultant at Guy's & St Thomas' NHS Foundation Trust in the United Kingdom. Dr. Akhtar completed full postgraduate certification in Cardiology, Intensive Care & General Internal Medicine with a particular interest in cardiogenic shock, heart transplantation, and mechanical circulatory support. He is also joined by Dr. Vasileios Panoulas, a consultant cardiologist at Royal Brompton & Harefield NHS Trust and honorary senior clinical lecturer at Imperial College London. He has clinical expertise that encompasses both general and interventional cardiology.
Additional resources:
UK multisociety consensus statement on the emergency management and resuscitation of patients with left-sided Impella support: https://heart.bmj.com/content/early/2025/12/17/heartjnl-2025-326896
Microaxial Flow Pump or Standard Care in Infarct-Related Cardiogenic Shock. DanGer Shock Investigators: https://www.nejm.org/doi/full/10.1056/NEJMoa2312572
Effect of Microaxial Flow Pump on Hemodynamics in STEMI-Related Cardiogenic Shock. DanGer Shock Investigators: https://www.jacc.org/doi/abs/10.1016/j.jacc.2025.04.062
Long-Term Outcomes of the DanGer Shock Trial. DanGer Shock Investigators: https://pubmed.ncbi.nlm.nih.gov/40888722/
Music mentioned in this episode:
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Transcript
Introduction and Podcast Overview
00:00:06
Speaker
Welcome to Critical Matters, a sound podcast covering a broad range of topics related to the practice of intensive care medicine. Sound provides comprehensive critical care programs to hospitals across the country.
00:00:19
Speaker
To learn more about our programs and career opportunities, visit www.soundphysicians.com. And now your host, Dr. Sergio Zanotti.
Impella Pumps in ICU
00:00:32
Speaker
The use of left-sided Impella microaxial flow pumps as a mechanical circulatory support modality is rapidly expanding in intensive care unit. However, standard life support and resuscitation algorithms are not directly applicable to patients receiving this therapy due to fundamental alterations in circulatory physiology.
00:00:51
Speaker
In today's episode, we will discuss emergency management and resuscitation of patients with left-sided Impella support. We will base our discussion on a recently published UK multi-society consensus statement.
00:01:03
Speaker
Our guests for this episode are two of the authors of this consensus statement. Dr. Wakas Akhtar is a consultant at Geist and St. Thomas Innesia Foundation Trust in the United Kingdom. Dr. Akhtar completed full postgraduate certification in cardiology, intensive care, and general internal medicine with a particular interest in cardiogenic shock, heart transplantation, and mechanical circuitry support.
00:01:25
Speaker
He has received multiple recognitions from the NHS for program development and training in critical care medicine. Dr. Octor is the lead author of the recently published UK multi-society consensus statement on the emergency management and resuscitation of patients with left-sided impella support.
00:01:42
Speaker
He was a recent guest on critical matters where we discussed ECMO emergencies. Today, we're also joined by Dr. Vasileos Panulas, a consultant cardiologist at Royal Brompton and Hartfield NHS Trust, an honorary senior clinical lecturer at Imperial College London. He has clinical expertise that encompasses both general and interventional cardiology. Dr. Panulas has a special interest in complex coronary angioplasty transcatheter aortic valve implantation, and percutaneous mechanical assist devices for the treatment of acute cardiogenic shock. He is the senior author of the consensus statements we will discuss today.
Importance of Managing Impella Devices
00:02:19
Speaker
Bas, welcome to Critical Matters, and Wakas, welcome back to the podcast. Thank you for having us, Bas. Thanks for having us. So we'll start, Wakas, with your perspective, and you navigate both worlds of cardiology and critical care. Why should intensivists care about this topic?
00:02:38
Speaker
Yes, certainly. i suppose cargenic shock forms a smaller proportion of the shock that presents to ICU, normally about 10 to 15% in many ICUs in the UK. However, it carries quite a huge um mortality, and that's not really improved over the last couple of decades. There's actually only two trials that have ever shown positive effects for mortality see in cargenic shock, which is primary PCI and Impella, which Vasea was an author on. And I think it's really key that if we only have these interventions that can provide benefit to these patients, and we really need to know how to manage these devices because it's not just the insertion, it's the day-to-day care afterwards that's important to get the best patient outcomes.
00:03:19
Speaker
Perfect. We would like to talk a little bit about the modality or the the methods, actually the methodology that you used in the UK multi-society consensus statement.
00:03:30
Speaker
Wachas, could you provide us a general overview of this consensus?
UK Consensus Methodology
00:03:35
Speaker
Yeah, so there's not really much ah much out there in terms of structured algorithms and or association practices that follow in patients who have impar-level cardiogenic shock.
00:03:45
Speaker
um So what we did was we reached out to the highest volume centres in the yeah UK, 11 of them, um and we um also collaborated with eight national societies representing cardiology, intensive care and multi-professional um groups. um And we tried to come together and provide um an overview for those first couple of minutes when a patient deteriorates and particularly within cardiac arrest, who's receiving impeller therapy support.
00:04:12
Speaker
um And we tried to go through um the data that is present, which was very limited, but was mainly based on iterative simulation to trial the algorithms, as well as clinical incidents and that had been reported.
00:04:27
Speaker
Could you tell us about the recommendation class and levels of evidence you use for this document? Yeah, absolutely. So ah as I mentioned, there's very limited and data. out There's many case reports around issues when people have deteriorated with impeller therapy. There's some aspects about its routine management. For example, um physiology can be very different. You can have a complete lack of postility with an impeller. And many people who might see a patient who's got a ventricular arrhythmia and no postility may assume that patient's gone into cardiac arrest. But...
00:04:59
Speaker
That certainly doesn't um always represent the case. um And that's why um a lot of this had to be synthesized from clinical knowledge, from iterative simulation um and incidents and reported cases. And so therefore the um level of evidence is quite low. um But there are some things that are well established about um the routine management of impaired patients, which is why the recommendation is higher in some in some classes.
00:05:28
Speaker
And you mentioned already that there was not a lot out there in terms of a of how to manage these emergencies and impella patients. What else does this guideline add to the literature? What's unique about this guideline?
Guidelines for Impella Management
00:05:42
Speaker
Yeah, so there is manufacturer guidance, of course, about troubleshooting impeller with the various alarms that um can occur. However, this algorithm is unique in that it brings together um troubleshooting for impeller device alarms and motor issues. with a patient approach which is well established in many other advanced life support situations. And so it brings together both the clinical aspect of managing the patient as well as trying to manage and troubleshoot the device and tries to provide some prioritization to make sure that both things are addressed um in parallel um to provide the best chance of saving the patient's life.
00:06:22
Speaker
Before we dive into the actual Impella emergency algorithm and the recommendations of the the guideline, Vass, I would like to go over major concepts related to Impella and would like to maybe start with a general explanation of what is the Impella device, what are its parts, what are the different types of Impella, a little about the physiology, and what's the ideal position from your perspective as an interventional cardiology who's placing a lot of these?
Types of Impella Devices
00:06:53
Speaker
Yeah, in essence, Impella is microaxial pump that you put percutaneously or also you can put it via surgical cut down. the There's two impellers that are supporting the left side of the heart, the left ventricle as we call it, and these are the Impella CP that can pump normally up to 3.5 to 4 liters. And then you have also the Impella 5.5 that is a surgical device.
00:07:19
Speaker
and I can produce even more. and Normally people use it up to 4.5 liters and 5. And this is normally put with surgical cut down via conduits that you normally sew either in the axillary artery or could be also direct aortic. There's also an Impala Rij that is used for the right ventricle, which is a bit more uncommon in clinical called practice, but it's another device that you can use to support the right ventricle.
00:07:47
Speaker
In essence, they, they have a propeller that spins at thousands of RPMs per per minute. And in essence, you ah continuously suck blood from the left ventricle through the inlet of the device and you pump it out into the ascending aorta.
00:08:05
Speaker
but it's it's ah It's like a continuous flow pump. It doesn't really care about systole diastole, even though it as a flow pump, it really relies on the pressure difference between the inlet and the outlet.
00:08:19
Speaker
And it's more efficient when there's less of a gradient between the left ventricular pressure and the aortic pressure. So we normally, and anazepam has been there for now decades. So we, I think across the world, there's been several...
00:08:36
Speaker
hundreds thousands of impellers that have been implanted um for several indications. But the concept of the device is is quite simple. If you see a speedboat and you can see the propeller of the speedboat, that little type of propeller is inserted into one of those devices, connected to a motor.
00:08:54
Speaker
And in essence, that motor spins that propeller and the propeller creates this principle of Archimedes' crew where it basically sucks the blood. And that's in essence how the device works.
00:09:06
Speaker
Excellent. In terms of a clinical trials, WACAS did mention the two therapeutic modalities that have shown differences in outcomes in patients with a cardiogenic shock, and one of ah one one of them was
Danger Shock Trial and Findings
00:09:20
Speaker
the Impella. Could you talk about the danger shock trial? What was the aim, what was found, and what are the implications for clinical practice?
00:09:29
Speaker
Yeah, so um the Danger Shock was published in April 24 in New England and it was a result of a many years of recruitment efforts done initially by the Danish team led by Jacob Muller.
00:09:45
Speaker
Then Germany joined the effort and finally also our center from the UK. Unfortunately, we couldn't change the name from Danger to Danger UK, but we we're still um we're still debating that.
00:09:59
Speaker
But in essence, it's a big randomized trial of 360 patients. Half of them were allocated to um having the microexal flow pump, the impella, and half of them standard of care.
00:10:13
Speaker
It was done for only for patients with ST elevation MI that came with cardiogenic shock. And the definition of cardiogenic shock would include echocardiography. So you needed to have a left ventricular ejection fraction under 45%.
00:10:29
Speaker
And also you need to have ah biochemistry um with lactate of over 2.5 or SVO2 is under 55%. And systolic blood pressure under 100 millimeters of mercury. So this was the definition of shock. And what is very different between this study and the ones that have been carried up to that moment what was the actual definition of shock. It's probably the first study that involves and includes in the definition echococardiography And for me, that was ah an eye opener. And one of the big reasons I wanted to participate and take us into that trial was the simplicity of the entry entry criteria.
00:11:10
Speaker
Because when the primaries come to your door, to your cath lab, the three weapons you have, I would say, is the clinical ability to see someone and examine them. Then you have, obviously, the observations, the systolic blood pressure, SATs.
00:11:26
Speaker
You can take a gas and you can do an echo. so and And this study basically encompassed all of those. um And what was the hypothesis was to show whether routine use of the microaxial flow pump would lead into a benefit in terms of mortality at six months. That was the primary endpoint, mortality at six months.
00:11:48
Speaker
and what what was excluded was people that had mechanical complications of MI, severe RV dysfunction, any contraindications for putting an impeller device such as LV thrombus for example or metallic aortic valve um and um it just showed at the end the primary endpoint it showed a big reduction nearly 13% absolute reduction in the risk of mortality at six months which in fact in the sub-analysis um that there was an age-related sub-analysis showed that if you're under 77 years of age you would get an even higher reduction mortality that was reaching 20 percent which means you only needed to treat five patients to save their life and and that's why i think this this study was a big headline in terms of clinical net clinical benefit for for the patients of course since then
00:12:47
Speaker
We have had several sub-analysis of the of the danger shock, trying to deep dive a little bit in the mechanistics of why does this effect happen.
00:12:58
Speaker
And also we had the other New England paper that showed the long-term effects of the use of a microexil flow pump compared to standard of care and it showed that that benefit seems to continue over time for up to nearly 10 years and we suspect that this probably is because of improved LV ejection fraction. So one of the most eye-opening sub-studies of the danger shock was the sub-study on hemodynamics where it basically showed that there are big reductions of the mean pulmonary arterial pressure as a result of the impella pump and also a big reduction of the native cardiac output. What does that mean?
00:13:44
Speaker
That means that intensivists in essence were using less inotropes and i had much lower vasoactive inotropic score. And that heart that just had the recent MI was resting appropriately and recovering appropriately. So in essence, not only probably Impella facilitated a better ah survival of people that otherwise wouldn't survive.
00:14:05
Speaker
but also the recovery, the better we recovery of hearts and probably and more and impressive gains and improvements in terms of ejection fraction by the end of the hospitalization. Even though we haven't actually shown that with actual figures, the fact that the long-term results suggests that the Kaplan-Meier curves keep diversifying from each other and that is suggestive that probably the main reason was an improved pump function.
00:14:35
Speaker
And i will stop there so I don't prolong this answer. No, perfect. and and And these are all very important observations and landmark study, obviously, because we we tend to jump into new technology very quickly. People are enthusiastic about it, but it's always from previous lessons in other areas, good to have the data.
00:14:57
Speaker
And on one hand, I do believe that and this is a very specific patient population, right? And we're using Impella as in a wider population clinical practice, and I'm sure more studies will come. But the the other aspect of um of the danger shock trial that that I would want to hear a little bit from your perspective is that these devices are not without
Complications and Management
00:15:21
Speaker
complications, right? So managing them appropriately and being very judicious in terms of selecting patients is also important. Any comments on that, Bas?
00:15:31
Speaker
Yeah, no, absolutely. That's a very fair point. and and And before I forget, because I think I didn't mention it, it's important to also note that danger excluded comatose cardiac arrest patients.
00:15:42
Speaker
So people that had prolonged down times and we didn't know their neurological status were not included in the study, because as you mentioned, previous studies are included in them. And then your logical injury kind of tends to mix up the results. So...
00:15:55
Speaker
and Arrested patients were included but as long as we had evidence that they they were not comatose. So in terms of complications, you're absolutely right. um Every device comes with its complications and generally MCS devices, mechanical support devices are notorious for excessive bleeding. And for example, something we noticed in danger was that ah that bleeding complications didn't always come from the axocytes, which is kind of the common belief.
00:16:23
Speaker
and Something less than a quarter came from the access side, but also we noted that more than 50%, 50.3% if I'm correct, percent of the bleeding happened after the removal of the device, which means that MCS, and particularly in the setting of an acute MI where people get antiplatelets, has big rheological implications on anticoagulation.
00:16:46
Speaker
So as such, you could see bleeding events even after you remove the impeller pump, and that's what we also noticed in danger. so um And what are the other complications that you get? So bleeding was around 23%, then you get renal filtration that was quite high, something around 44%. And that's a combination of selection bias where basically you know people that shouldn't have survived, survived, and had multi-organ failure, et cetera, and as a result, they needed filtration.
00:17:15
Speaker
But then there were also some device-specific parameters that potentially led to more hemolysis, and these were suction events. And in my books, that normally means that the impella device was either positioned in an inappropriate place, so under the mitral papillary muscle, that can happen quite easily.
00:17:33
Speaker
and Number two, it could be because you had a big blood loss or volume loss and as a result you're suctioning on the ventricle. Or number three, because you had an RV that was also not coping in the end and you didn't manage that appropriately.
00:17:45
Speaker
And suction events seem to and create more hemolysis. And we know that hemolysis can be very traumatic for the kidneys because of the plasma free hemoglobin that tends to create AKI ah very easily.
00:18:00
Speaker
So on the other impeller-related factor for and AKI and renal filtration was the higher speeds. So if you if you use a device, and we were advised to use a device at higher speeds, but sometimes we we would go down to P6. P6 is like the power level, and you can go from P1 to P9.
00:18:20
Speaker
so if you use it at P8, P9, you're more likely to cause more emulsitude because purely of the speed of the of the motor and the propeller. And so these kind of AKI infiltration was one of the highest numbers of complications. And then you'd have a small percentage around five, six percent of limb ischemia.
00:18:41
Speaker
and some sepsis that was also associated because obviously you have a device, people can get infections of any sort and obviously whatever you have in the body can precipitate the infection. So that the infection size were also slightly higher than the control arm. But I think the most um prominent strokes were again very little.
00:19:02
Speaker
I think the most prominent too that seemed to have been highlighted is the bleeding and the filtration. And I think a lot of it we can improve and both as interventional cardiologist, but also from an ITU perspective on how to manage those devices, because there are tips and tricks and best practices that we can promote to reduce the the number of complications that we get on the device. But obviously you need constant education and you need simulation training.
00:19:31
Speaker
And there's several courses that people can go on and educate themselves. But I think it's also good through this posts to to podcast to be able to and advertise them because in each country, there's always courses related to the management of Impela and its complications. I think people have to go there as a team. It shouldn't be just the international cardiologist. It should be the whole team that manages those patients from the beginning to the end of their journey. And I think that's the only way to tackle the complications.
00:20:01
Speaker
Absolutely. You mentioned that position and when we talk about the emergency response, will we'll talk about malposition alarms. What's the ideal position of an impeller catheter device?
00:20:16
Speaker
So, yeah. So in essence, for um for the CP that's like the most commonly used and is transcaster. You want to make sure that pigtail of the device is pointed towards the apex and that you're not trapped under any mitral papillary muscle.
00:20:35
Speaker
um Normally they say that the distance between the aortic valve and the inlet should be around 3.5 centimeters, But obviously that can vary a little bit, I would say at least a centimeter up or down, depending also on the LV size, because obviously you can put an impella in someone with dilated cardiomyopathy and a ventricle of eight centimeters.
00:20:56
Speaker
The impella will be sitting a bit more deep and to to make sure that it's stable. But what I normally advise people is to, when they across the Arctic valve, because that's the kind of critical step to to put the impella exchange for the wire.
00:21:12
Speaker
You go to an arial position in the cath lab or ario-coidal position in cath lab, and that's basically like your three-chamber view on TOE or transthoracic echo is a long axis view. And then you can actually and see whether your wire or your pigtail is free before you position your impella. And then do your impella implantation, but then obviously at the end, before you leave the cath lab,
00:21:35
Speaker
And because obviously there is a step that you have to exchange the pill away sheet for a blue repositioning sheet, you want to make sure that that impeller does not move. And before you leave the cath lab, you do a final check both fluoroscopically but also with use of echocardiography. Because if you send someone to intensive care with an impeller strap under the pillory muscle,
00:21:57
Speaker
What's going to happen? You're going to get more suction. People will come and play with the device. Inevitably, someone might also remove it altogether from the LV or someone might push it too hard and create a perforation or a problem with the mitral capillary muscle. So you basically open yourself and to several complications that can happen down the line. so A very simple and easy step is once you're done with this procedure and you have ensure that you put it in the right place facing towards the apex 3.5 centimeters as we said free from the papillary muscle on the area of use.
00:22:32
Speaker
Do a final check with echocardiography, make sure everyone's happy. Note down the number on the impeller shaft that's coming out of the leg and make sure that that number is documented. It's like simple stuff. Make sure you secure the device with a TUI BOSS so that it cannot be moved during the transfer of the patients because all of that adds up. and So these little best practices, and I think also the company has a created a list of those, but these are really important steps to make sure that you get it placed in the right position, but also you maintain that placement. So no one down the line from the cath lab to the intensive care, wherever that patient goes, moves the device and then you end up inadvertently having complications that you don't really want.
Impella in Various Scenarios
00:23:21
Speaker
Perfect. We talked about ST elevation with cartogenic shock as an indication and a danger shock trial. What are other common applications or clinical uses for Impella today that you want to mention?
00:23:37
Speaker
Yeah, so and in hospitals that face... ah Patients with cardiogenic shock like ours, we're like a quaternary center and transplant center, we get a lot of referrals for cardiogenic shock from various etiologies. And the reality is that AMI is only accounting for about 44% of patients in cardiogenic shock.
00:24:00
Speaker
So you see a lot of patients with, for example, mycorditis, and that's that's an excellent example where... Impella can be used to rest that ventricle and allow for recovery. and Often these patients sometimes can be rescued on ECMO and then you end up with ventricles that are totally and overloaded, aortic valves that don't open and the risk of thrombogenity and clot formation is very high and there's like an emergency unloading that has to happen and you can do that very nicely with an Impella device. Then there's this progressively deteriorating and stage heart failure patients that, for example, DCMs or ischemic cardiomyopathies that are sliding down and they're heading towards transplantation. And despite your little inotropes, millerine or whatever you like giving, they they keep that gradual deterioration. And then you put them a pallet device and you bridge them very nicely to and to transplantation or advanced therapies, elevated, et cetera.
00:24:57
Speaker
And of course, there will be also that cohort of patients with cardiomyopathies that come in as a first presentation crashing, and you can always offload them, and put them in a 5.5 device that supports fully their left circulation, and invariably, the right, even if it's moderately plus impaired, can cope.
00:25:15
Speaker
and then you can start loading these people sometimes often with and good medical therapy and guideline-directed medical therapy. And we have seen a decent cohort of patients that are aware of a publication um that also shows that you could recover some of these hearts just with guideline-directed medical therapy whilst they are on the device 5.5.
00:25:35
Speaker
And then, of course, there's a big use of Impella for what we call protected PCI, particularly when we want to do very difficult procedures that we have been doing traditionally even without support but it has been a is it a scary process for the operators and often is ah is a quick job as I call it so you go in you do the best thing you can with balloons and cutting balloons and stuff as quickly as you can and get out as fast as you can and sometimes you don't do quite a good revascularization job
00:26:10
Speaker
So Impela tends to provide that support for these patients. um That gives the operators the confidence to do a better job and use their you know rot ablations, their lithotripsy balloons or cutting balloons and get as good a result as they can get for that patient.
00:26:28
Speaker
So these are kind of the the main areas. I think if I was to sum them up, it would be the kind of high-risk protected PCI era. And it's exciting. We have two randomized trials coming up. Already we had the PROTECT-2. That's quite an old trial.
00:26:43
Speaker
um But now we have the BISIS-CHIP-3 that we'll announce in ACC, and we will have the PROTECT-4 next year. So we will get more information about potentially which are the patients and patient characteristics that could benefit and how exactly what kind of maneuvers we should do as operators to give the patients the best benefit.
00:27:03
Speaker
So high-risk PCI is one arena, and then is the carogenic shock that not only involves ST elevation MI, but also involves all these end-stage cardiomyopathies that could be ischemic, or it could be DCMs, or it could be mycorditis that benefit from the device. Obviously, for this later group, there's no randomized evidence yet, but I think It's very difficult to have randomized evidence, for example, for a 35-year-old that dies in front of your eyes from pump failure and myocarditis. It will be very harsh to randomize that person to MCS versus no MCS. So I think we will never see randomized evidence for the later group. But I think it's it's nice to have, at least with danger, some randomized evidence on the AMI arena to show that in certain populations, there's danger-like patients, as we call it, there's a big benefit.
00:27:54
Speaker
And I'm hoping that you know we will we will carry out more studies in the future, and that's the reality. In our world of evidence-based medicine, this is how we we like to evolve. And I'm really hoping that we will be part in this journey in the future as well.
00:28:11
Speaker
Within the indication of cartagenic shock, and obviously you were talking about a wider and group of patients here, just beyond ST elevation, acute MI.
Impella and ECMO Use
00:28:22
Speaker
When is Impella useful on patients who are already on ECMO?
00:28:29
Speaker
Yeah, that's a very good question. So in essence, when you have someone on ECMO, you use Impella as what we call an unloading tool. Even though that term is quite a difficult term for people to understand, unloading means trying to take away some of the energy that the heart uses.
00:28:49
Speaker
And ECMO in principle can unload the heart because basically it reduces the preload. So it reduces dramatically the volume of blood that goes into the heart. The problem with ECMO is most of the times the afterload, which we can basically name it also the mean arterial pressure that we create once we put some on ECMO, tends to go up. And if people are not very careful about managing the afterload, they can lead into an LV that is distending on the heart that it's pumping ability goes down.
00:29:24
Speaker
so When is Impala useful in these patients? am There is ongoing randomized evidence that will tell us exactly when. But until that happens, I think in our in our hospitals, we think that Impala is quite helpful when you see very low pulsatility, so the pulse pressure is very short.
00:29:45
Speaker
and I'm talking about you know under 20 millimeters of mercury or less. When you have aortic valves that do not open and then the patients are at risk of clot formation both within the left ventricle but also in the aortic root.
00:30:00
Speaker
When patients go into profound pulmonary edema and if you have a caster you see you know LVDPs that are more than 30 millimeters of maker and wedge pressures that are sky high.
00:30:11
Speaker
These are the kind of cases where and an unloading with an Impala device really solves the whole problem. Obviously, the next natural question is, you know, why don't we do it on everyone? We don't do it on everyone because double the device, double the risk of complications.
00:30:28
Speaker
So, you know, bleeding on the combination of the devices can reach up to 60%. So ah simple stuff like that. Same thing goes for hemolysis. So the the clotting abnormalities you get on the combination is is quite remarkable. So I think teams have to be very well geared up on managing these devices if they want to manage them together.
00:30:50
Speaker
But obviously, if done properly, you can get some phenomenal saves. And in our institutions where me and Waka's work now, we are we're one one big trust, Gaisen St. Thomas' has all three hospitals.
00:31:03
Speaker
We've seen several cases that have been managed with ACMELA and had they had a great outcome. But as I said, we need to be you know cautious and work in a multidisciplinary way to to get the best outcomes for these patients because they're never very easy. They're always very difficult to manage.
00:31:22
Speaker
Excellent.
Emergency Management Algorithm
00:31:23
Speaker
Let's talk about Impella emergency algorithm and the actual recommendations from the consensus statement. Could you walk us through the core principles? and And I do believe that there's something really important here to emphasize in terms of how we should approach these emergencies in terms of team allocation.
00:31:42
Speaker
Yeah, of course. So um the algorithm is very much designed for those first couple of minutes when a patient goes into cardiac arrest, but it can be applicable to many emergency scenarios. so you can translate some of the interventions to those situations.
00:31:56
Speaker
But importantly, it's not meant to be a standalone document. um I think there's a couple of things. One is that you have to have regular clinical familiarity with Impella, and you can override the importance of that. And I think secondly is that it needs to be complementary and implemented through the provision of structured training. um And it's really important, I think, to have simulation as part of that so that you get familiarity with the device itself.
00:32:20
Speaker
But yes, the structure of the algorithm focuses on, um in parallel, working with a team that focuses um on the impeller and the team that focuses on the patient because they're slightly different skill sets. And it may not be teams necessarily who can do both of those functions, but it's both important that are present. And then ideally having a team leader who can oversee both sides of the interventions that are occurring. um And that's pretty much how the um algorithm structure follows. And it's very similar to um strategies that are employed in ECMO and um other forms of mechanical support when patients deteriorate.
00:32:57
Speaker
What's the initial, and and in terms of the initial response, what triggers an impeller emergency? Yep, so um for this algorithm, we specifically looked at cardiac arrest. um So the initial thing we specified was that the patient should be unresponsive and are not breathing normal normally, which is a normal entry point for most advanced life support algorithms. Importantly, and most of the patients, especially in our institution, are not intubated or kept to sleep. So they're actually awake. um And particularly with our 5-5, we expect them to be mobilizing in preparation for breast transplant. CPs are normally um not mobilized unless it's put in in a more secure manner. and So the unresponsive or not breathing normally is an important um entry point.
00:33:40
Speaker
And then um there's real lack of evidence about what you should be using as criteria for defining a lack of adequate circulation. So entitled CO2 has some evidence and the American guidelines particularly have used it in some MCS troubleshooting algorithms to have entitled CO2 of less than two kilopascals as a um cutoff. But as I mentioned, not many patients with Impelleron institution are intubated. So therefore we use MAP really as an entry point. And again, that lacks any evidence. But through consensus, we agree that ah mean arterial pressure that's been um checked in terms of the transducers adequately functioning and leveled less than 30 millimeters of mercury as an entry point um into the algorithm.
00:34:25
Speaker
so in terms of numbers, and less than 30 millimeters of mercury for for blood pressure, and you talked about entitled CO2, less than 2 kilopascals, which would be less than 15 millimeters of of mercury for those who use that denomination, right?
00:34:41
Speaker
Yeah, exactly. um And I think it's important that there's no there's no one um one tool you can use. So it's often the trend of the patient, how they've been behaving, and particularly if they're intubated, it can be quite difficult. um But I think that um on balance is probably the most pragmatic way, at least until there is some evidence, because it's likely to be a deficit of trials in this area because it's not very clear what an adequate circulation is. um And I think that's well defined within cardiac arrest where you have some of these people who are immortal survivors, even through prolonged periods of resuscitation, and actually whether they have some ability to maintain um sufficient flow to the brain, even at lower lower maps um to prevent poor outcomes.
00:35:23
Speaker
Before we talk about the actual interventions, what's different about cardiac arrest in somebody who has an impella? Is there and any particular difference that you want to make sure you emphasize?
00:35:36
Speaker
Yes. So I think the recognition is important. So I think that's one key thing that um I've often picked up um even within our institution because we have lots of rotational staff that come through is the lack of pulsatility, which um clearly is not something you want to have. You want to make sure the heart is ah ejecting well.
00:35:53
Speaker
But it very often does happen at the start of impeller therapy, especially Vas mentioned, you want to have a reduction in your vasoactive use. So you want to maximize the amount of support you can get from the impeller. And often in those situations, people will have a lack of postility on their arterial line. So think important recognition that that is not and not inherently so a problem, um especially if you've got adequate perfusion pressure and with your mean arterial pressure.
00:36:17
Speaker
um i think the ah other aspect is just the device itself. um If you're going to be starting CPR, there obviously was some FDA notices previously about perforation of the LV with impeller malplacement.
00:36:34
Speaker
And I think it is an important consideration in CPR, although we've never seen it, is that um CPR can obviously cause the heart to distend and the device to migrate. So it's an important consideration, and particularly with patients who might have um particularly um aneurysmal or thinned left ventricles. However, pragmatically, if you've ascertained that the patient doesn't have an adequate circulation, then you're not really going to have much option other than to be able to perform um CPR while you try to remedy the situation.
00:37:03
Speaker
Is there any intervention with the Impella when you start CPR? Yes. So um the company recommends a reduction in your P setting. They don't specify um in their manual exactly how much, but in the algorithm, we decided to recommend a reduction to P2 before starting CPR. And the reasoning behind that was um you're going to get movement of the device during CPR because it's often not going to be completely fixed in place. And obviously, your heart is going to be moving around the device as well during CPR.
00:37:31
Speaker
And what you don't want to end up doing is having the inflow, which if you actually look at device, um is almost quite a sharp cage um near the um end of the device. And if that was to be at a high P setting and cross into the um aortic valve, there's a possibility that it could entrain the aortic valve leaflets and cause significant amount of damage.
00:37:52
Speaker
And then if you've got a patient who was already deteriorating and potentially had gone into cardiac arrest, and then you render them with torrential severe aortic regurgitation, that's not only going to hamper your ability to get them back, but actually, if you're going to have to rescue them with additional mechanical support such as ECMO, um that's going to provide even more difficulty because most most mechanical support doesn't function well with severe and torrential aortic
Restoring Circulation
00:38:16
Speaker
regurgitation. So that's why we recommended a reduction to P2 before starting CPR.
00:38:23
Speaker
In terms of ah the recommendations, the priority, yeah obviously, in these cases is to restore circulation by either resolving device dysfunction, which is what the impeller team is trying to figure out, or that caused by physiological problems, which is what, I guess, the patient team is is trying to figure out. Can we talk about the impella troubleshooting and maybe Voss, you can walk us through how we should think about the potential problems. Obviously, these devices have alarms that tell you this might be a potential problem. But what are the main categories and what do you recommend our listeners to to be thinking about?
00:39:02
Speaker
Yeah, absolutely. I mean, there's, there's obviously a million of alarms that you can get, but I think, um, in the, for the matter of time for this podcast, I think it'd be nice to highlight the most frequent problems that you can get with a device and,
00:39:18
Speaker
I think the number one that we experience is the suction alarm. um And as I mentioned before, a suction alarm basically means that your inlet of your device, where that little cage is, as Wak has mentioned to you before, um is stuck to the LV wall.
00:39:34
Speaker
And why could that happen? I think can only happen in in three big scenarios. And in fact, if you see it completely, like theoretically happens before, because the LV has very little preload.
00:39:47
Speaker
And why would the LD have little preload? It could be because you have a lack of intravascular volume. So either you're bleeding from somewhere, could be the impella cytophaxis, or it could be another big GI bleed that you're not aware of.
00:40:01
Speaker
So number one, volume loss generally in the circulation. Then number two is, as we mentioned before, bad positioning on the device. So if the device is put under the mitral papillary muscle, for example, it's much, much easier to create suction alarms. A lot of these devices can be headed towards the mitral on the posterior wall.
00:40:22
Speaker
And there's very nice papers out there that now comment about malpositioning and ways to identify that both with echocardiography, but also in the cath lab.
00:40:33
Speaker
And if I just mentioned the two fluoroscopical approaches that operators should be doing, one is the areal cordial that, as I mentioned before, is like the long axis view of echo. and it opens up your LVOT, LV and left atrium. And then there's the eleo cranial view that basically is the equivalent of the forward chamber view and you can very clearly show whether that impede is heading towards the lateral wall under the matropocular muscle. So positioning, very important also for suction. And the third and often under-recognized situation that leads to suction alarms is RV failure.
00:41:09
Speaker
And a lot has been said about RV failure and how you diagnose it, but I think predominantly you need hemodynamics to be able to diagnose RV failure and that that includes your pulmonary R3 pulsatility index, that means you need to have a PA castrine, but also obviously more simple things like the CVP when that goes up and yet you have an empty left ventricle, you have to figure out what's going on. But I think these three main factors are the ones that lead to suction alarms.
00:41:39
Speaker
And then two other very common alarms that people should be aware of is when your motor current, and and that's the little green line on your device, is flatlining. and That normally flatlines when the device is and both inlet and outlet of the device is in a single chamber. So either the device has gone all the way into the left ventricle or the device has come off in the aorta.
00:42:05
Speaker
And when that happens, you will get a respective alarm. But when the device in the aorta, the arterial trace of the device will show aortic trace, an arterial trace. And when the device is all in the left ventricular, you will see a left ventricular trace.
00:42:20
Speaker
Of course, there can be other problems related to the urge pressure, etc., But this can be a little bit more complex. And I think for our listeners today, for the purposes of this podcast, ah probably we should just focus on these main alarms, the suction alarm, and then the positioning alarms that are probably all of them relatively easy to solve in a quite rapid fashion. um The other thing that we should note, if if someone has, for example, tamponades, you might again get a suction alarm. That's quite rare, but can happen, particularly when you have corner interventions preceding
00:42:56
Speaker
uh the admission to itu you also should be wary that if you have someone with tamponade again what happens is you reduce the preload to the left ventricle and it's very easy to create a suction alarm Similarly, if you have someone on ECMELA, so ECMO and impella combination, if you really go very high up on the ECMO RPMs, what you're going to do is you're going to reduce massively the preload to the left ventricle. And if at the same time you're running your impella at a very high and power, it will end up diminishing. And sometimes you can totally make the left ventricular cavity disappear and have, again, a very nice suction alarm. So few things to think about, but these are,
00:43:38
Speaker
Suction alarms are the most common headache for ITU teams for impellers. And I think, hope this kind of brief talk makes it clear for people to look for a reduction in the intravascular volume, positioning of the impeller. You can call it malrotation, you can call it malposition, whichever way you like, and problems with the RV failure. And of course, be careful when you have ECMO and impeller-ECMELA configurations.
00:44:05
Speaker
Excellent. And just in terms of ah of summarizing, obviously for suction, consider improving preload by giving a bolus. I think that the paper recommend recommend recommend recommends starting maybe with 2.5 mLs per kg as a starting point.
00:44:20
Speaker
A very important aspect that I want to emphasize is the importance of exposing patients and really looking at all insertion sites, looking what's going on.
Post-intervention Assessment
00:44:28
Speaker
Is there bleeding, right? Could be causing this, as you mentioned.
00:44:32
Speaker
And then for the impella position unknown, it's either... too far in or or way out, looking also at the at the arterial trace lines. and If it's too far in, you will see the LV trace and the action there is under echo to pull back the catheter to the optimal position.
00:44:49
Speaker
And if it's too far out, you'll see more of an aortic tracing. And again, I mean, echo guidance to reposition it and then come back to the previous P setting. Since we mentioned we would go to P2 when we have these problems.
00:45:03
Speaker
How do you evaluate adequacy of circulation after you do these interventions?
00:45:12
Speaker
Just before i I mentioned that, I think ah to highlight when the impella is out in the aorta, it depends whether the peictile part of the impella is still in the ventricle, in which case you could reposition with echo. But if the whole impella, including its little peictile, is out in the aorta,
00:45:30
Speaker
i would I would probably advise strongly against doing it with cogynos because that might create a complication. So after this probably has to be done under thoroscopy in the cath lab.
00:45:42
Speaker
Now, going back to your previous question about adequacy of circulation, I think, and again, in arrest situations, most people focus on some basic hemodynamics and it depends what you have at the time of the rest.
00:45:57
Speaker
Obviously, and we all look at maps and normally most teams like to have a map around 60, 65. Of course, there's also another Northshock trial running that might lower that threshold, but that's roughly the immediate response that we want to achieve and start start having good and title suit twos. Then if you started going and and looking at an echo,
00:46:19
Speaker
You want make sure that you have LVOT-BTI that's slowly creeping up and you don't have profound RB failure that you need more support. and Of course, you can go to more advanced hemodynamics. You can check your cardiac output, cardiac power outputs, your puppies.
00:46:36
Speaker
and And then last but not least, your biochemistry, because ultimately, if everything is going well, what you're going to see is your your lactate will start to reduce. You will see good oxygenation.
00:46:47
Speaker
And um you will also see that these people have good end organ perfusion, for example, they might start peeing again and in the good amounts. So these are the the common things that we look for. Some of them are more immediate than others, but I think it's always a holistic approach.
00:47:02
Speaker
And of course, the clinical bit is also very important, simple things like capillary refill time and stuff like that, reduction of the modeling of the patient, reduction in the inotropes that you need to use. All of that is clinically very important.
00:47:17
Speaker
Waka-san also is the master of intensive care. so No, no, no. So I think that's exactly right. And the echo, the couple of um things in the algorithm design. So one, echo we didn't include till a little bit later on during the assessment stage, because often it takes you at least a couple of minutes to even find an echo machine and turn it on so it's ready. Otherwise, it would have been implemented much sooner um within the algorithm. As Sebastian said, it's extremely useful to really assess pathology such as tamponade or ventricular dysfunction.
00:47:47
Speaker
And um with regards to the traces, we discussed the smart assist was actually is a very useful tool for identifying a malposition in particular, but actually it's only present at P4 and above. um And so therefore we didn't decide to include it in the immediate algorithm because as Vass described, actually having the motor current is actually probably the best indicator if you've got a flat motor current that you have an issue that you may need to resolve. um And so those are just the two points in the practicalities why why those were ordered in that way within the algorithm.
Holistic Patient Care
00:48:17
Speaker
and Then obviously aligned with all the impeller troubleshooting is the patient aspect. and We were very specific you should just follow normal um advanced life support protocols for that. Obviously does add a bit of complexity um around ventricular arrhythmias because as you described previously, people can tolerate those with an impeller in situ. That would be the equivalent, for example, of a pulse VT and the patient is conscious or has got an adequate map. and In that case, um within ALS,
00:48:46
Speaker
and We didn't decide to um ah deviate in terms of the use of adrenaline, for example. However, it's important consideration, Vasya said, that the afterload is a significant issue for a mechanical so but support devices. And, for example, within the ECMA algorithm, we thought it was of significant enough concern to... limit its and use. But in this case, we would recommend normal ALS protocol, but be considerate about um whether the patient actually does have a perfused rhythm with ventricular arrhythmias.
00:49:17
Speaker
Vakas, any comments on holistic care aspects?
00:49:22
Speaker
Yes, ah I think it's really important because we do um all these things to try and save the patient's life and we can be very invasive. So, you know, we were talking about um PCI interventions and Pella, and then we might also be talking about ECMO and Pella. And these are all incredibly um invasive things.
00:49:39
Speaker
um And we have to make sure that we're not making our patients suffer um without having a significant likelihood of recovery. And also really considering what it is that the patient actually wanted. And very early on, we will make sure we involve um our palliative care team who who are excellent as well as families and teams in terms of interacting to understand and and what the patient's values, preferences um and the lived experience to allow us to align our treatment strategies with that individual's um goals and priorities. I think that's really important in the overall care of the patient, but also within um the active resuscitation phase, um which in the UK would be very big proponent of is to make sure that we give the opportunities to families to be part of the resuscitation effort to come and watch if that's something that they want to do. Of course, many may not want to do that, but I think it's important um that that consideration is made.
00:50:32
Speaker
as we as we close and summarize, any pros and pitfalls that that you want to share?
00:50:42
Speaker
Yes, I think VAS highlighted a couple of them, which I think are really key that I think are quite common errors in management of impelitis. One is positioning. I think it's really key to get your optimal positioning, particularly in the cath lab before they come down to the intensive care units. And I think it's often the case that people you know may may not have initially suction and you're overall happy with the device, but actually if it's not optimally positioned, for example, if it's intermittently abutting the septum or the mitral valve apparatus, you will end up getting some hemolysis. And that is likely what may be triggering a significant proportion of renal injury to these patients. And therefore, we monitor um in our units and plasma hemoglobin every day um on these patients. And i think it's really important to get that optimal. And similarly, in terms of positioning, I think groin position of the device um can often be an issue. so and there is a little bit of an issue with the fact that the pi um the sheath that's left in at the end is smaller than the hole that you've made. And actually the angle that the impeller goes in is really key and we and emphasize keeping it at 45 degrees and making sure the insertion is fully placed. And actually, if you are having bleeding issues, VAS and our cardiologists place ProGlides in and those can be cinched around the device to reduce bleeding rather than the traditional and pressing really hard and putting a um compression device over, which i did think is necessarily always the best option in these patients.
00:52:10
Speaker
Excellent. as As we close, we'd like to ask a couple of questions unrelated to the clinical topic. Wakas, Vaz, are we okay with that? Yeah, sure.
00:52:22
Speaker
Absolutely. Vaz, you go first. What music album or playlist would you want with you in a prolonged isolation period? Example, you're on a deserted island or a new pandemic comes in.
00:52:34
Speaker
Well, have him I have a few favorites these recent months. One is... ah Teddy Swims and Learning. Then I really like Miles Smith.
00:52:46
Speaker
He's got some really uplifting songs. And Alex Warren, if I want to get a bit depressed at times. I think these are the three tops at the moment in my playlist.
00:52:58
Speaker
Excellent. What about Waka's? What would you want? I suppose at the moment, i mainly listen to Bon Iver, his new, newish album but now, Sable, Fable. It's got a really excellent range of songs. I could listen to that for a long time.
00:53:15
Speaker
Perfect. Walk us. We'll continue with you as we close. What would you want every listener to know? Could be a quote or it could be a final thought.
Personal Reflections and Teamwork
00:53:26
Speaker
Yeah, ah funny enough, I was um on TikTok and I thought this one really resonated with me. as We often worry in our lives a lot about ah decisions, research, career development, all those things. And we see a lot of deaths in intensive care. think it's important in the context of our busy stressful lives to remember to live our lives and enjoy them.
00:53:49
Speaker
And Vaz, we'll let you finish the podcast. What is the thought a or quote that you want to share with our listeners?
00:53:58
Speaker
I am for me, I think the most important because a lot of people talk about work and life balance, balance but often work is also our life and we love doing it.
00:54:08
Speaker
i think when you tackle complex patients like the one ones with cardiac shock, just always remember to be a team. um stop the hostilities between subspecialty and the other and just join up together forces to to beat this thing that's called carogenic shock that is very complex to to face. so Someone cannot do that on their own. So just just be a team and and love each other and work together.
00:54:32
Speaker
I love it. And at the end, we don't own the disease. We just owe it to our patients to give them the best possibility to survive. And teamwork will definitely give them that. I want to thank both of you first for the wonderful consensus statement. It addresses a a growing area, a very important aspect. I also want to thank you for giving us the time and your expertise today.
00:54:56
Speaker
And I look forward to having you back to talk about cardiogenic shock. Thanks, Vakas. Thanks, Vaz. Thank you for listening to Critical Matters, a sound podcast. Make sure to subscribe to Critical Matters on Apple or Google Podcasts and share with your network.
00:55:12
Speaker
Sound's transforming the way critical care is provided in hospitals across the country. To learn more, visit www.soundphysicians.com.