 Hello everyone, my name is Karthik Baluri. I'm an assistant professor for Cardiovascular Critical Care Medicine at Baylor College of Medicine. Today I'm here to talk about our experience with COVID-19 in a critical care aspect. The primary focus for me is to shift it toward perfusion and ECMO. Prior to getting to ECMO, what have we faced? So this is our talk, this is part one. Dr. Chatterjee will be joining me next after with his insight. I will be talking about the pathway to ECMO. So a quick epidemiology, all of us have been inundated with COVID facts, it's all over the news, it's all everyone talks about, we're also facing it as a population. So general mode of transmission, we know that it's respiratory droplets, you know it's contact with infected service, however now recently that's been debated by the CDC. Airborne aerosolized respiratory droplets which can be seen during procedures that we see like in the units like BIPAP or any type of airway related procedures. If you have coronavirus or if you acquire it through these methods it usually takes about four to 14 days for it to have presenting symptoms after which there's a progressive course and there's different outcomes. Overall what the way we control this infection is to contact and droplet spread, prevention with simple masks, eye-face protection, three to six feet of distance, social distancing and different agencies like WHO and CDC have different requirements. Overall this is a very severe disease, however majority of the patients in these statistics range between 60 to 80% only suffer a mild form of it, however there is the component that gets progressively worse and this is about three to six week course for these patients with a severe form of COVID. So how does COVID-19 lead to respiratory failure? The overall aspect of this virus is that it infiltrates, we respond to it and then sequentially we get worse. There's an asymptomatic state followed by our upper airway tract symptoms and then slowly our hypoxia and there are changes in our radiological imaging setting. What are these events that take place? It's a very busy slide but this is a graphic representation of the various cascades and processes involved within our alveoli in our lung. Now the virus binds to everyone's possibly heard about the ACE2 receptor which is lining majority of our alveoli respiratory tracts endothelium, cardiac, myocytes, it's in the brain, it's found in the GI tract, it's a pretty prominent and widespread receptor so it's a potential target but for this sake and for this virus purpose our respiratory tract is pretty much where it sort of shows tropism toward. It attaches, infiltrates our cell and it triggers a massive inflammatory response. Now the inflammatory response for this virus is determined predominantly individually like not everyone has a clear cut cookie cutter response to it. Some people can deal with it and they'll have mild symptoms that'll go away however our problem with respiratory failure starts here. As our host responds to the viral infiltration progressively gets worse it leads us into different situations in which macrophages, antibodies, interferons, interleukins, all these inflammatory modulators start eating away in basic terms at our respiratory tract and our functional unit of the lungs which is our alveolus. This is where oxygen is being transferred from our air that we breathe in into the bloodstream so it's a very vital component to our existence and that's why this is such a severe disease. So just in general these are some of the findings that we've seen. CT has been shown to be a better modality in detecting changes in regards to COVID-19. Certain patterns which are these patterns are present in other disease states however in the clinical context of you acquiring this condition you being tested positive for it or you presenting with exposure to it. If you find these findings it's pretty indicative of potential and progressive respiratory failure. You have ground glass capacities and that's the capacities you see there in the corner. Then you'll see patterns like crazy paving which is like these cobblestone appearance and it's like it's like the roads that you see. Vascular dilatation so this is the other component of your lungs the blood interface you'll see the vascular which are also being affected by this virus. You see something called traction bronchiectasis in which these airways get really stretched and enlarged and ultimately lose their functional purpose. As of May 21st very recently New England Journal of Medicine released an article sort of cataloging the changes of this virus. Gross morphology and microscopic like patho histology. So one new component they've seen a lot is something called endothelitis basically our endothelium which is the cells that line the inside of our blood vessels are just extremely inflamed that's one. The next thing they've seen is micro thrombi and this has been passed along a lot that there's a lot of micro thrombi formation in this alveolar capillary interface areas in which is all of this all of these issues all this inflammation it ultimately leads to one simple thing oxygen that comes into our body needs to get put into our lung because of all this inflammation all this endothelitis these thrombosis and all these other secondary effects to the host's response that that barrier is created and that interface where oxygen can easily be transferred from air that we breathe in put it into our blood is destroyed. The severity of how much this occurs in different times of people is dependent on the host factors that means if you're susceptible to it we don't know exactly which conditions make the certain person susceptible however we do know the general things of age heart disease we see it less in children they say but we see a different form now and other comorbidities associated with this has shown to have a more severe outcome. So what do we do this patient comes in and now you know how this virus affects us and how it infiltrates our lungs how it causes the inflammation in our host system and then ultimately messes up our ability to oxygenate our blood. So over the course of the last three months there's been three major issues that have been associated with COVID and critical care medicine. Number one understanding what it is and that is an ongoing process by doing studies from Wuhan and everywhere else. The next thing that what do we do and how to prepare for it how to protect our own people and staff that's another focus and then the biggest thing was what if we have a increased amount of patients that surpasses our hospital capacity which is the surge which we circumvented. Majority of external factors took place like mitigation strategies we tried containment the contact tracing and stuff like that but these mitigation strategies with social distancing quarantine and everything has led to a slowly flattening of the curve as of now. So our ICU luckily in Houston here in St. Luke's now wasn't inundated we were able to handle the capacity that we got in. However that's just one aspect of this entire thing. The other aspect of this is okay versus another respiratory failure patients such as with COPD or you know pneumonia. How does COVID defer and what do we do? So we've established amongst the collaboration with pulmonary critical care cardiovascular ICU anesthesia surgical ICU group of critical care doctors and administrators everyone's got together and created a agreed to format which basically sets a few rules and protocols and the patient came into our ICUs and how do we treat them. Once again this is important to remember oxygen needs to be delivered to the blood how do we do that. First step we isolate them droplet and make everyone safe health care workers and and the patient himself. We initiate low flow oxygen which one to six leaders of oxygen to see if their oxygen saturations are going up of 92 percent. Time goes by and as this inflammation is occurring in that patient's body he's requiring more and more oxygen. Now we would escalate to something called a non-rebreather mask and this is approximately 15 liters per minute and there's no humidification at this point. Simultaneously this patient would be transferred from a different aspect from a from an investigation room to a critical care isolated unit and that would be happening to that patient. The next major thing is something called heated high flow or heated humidified high flow nasal cannula and it's called vapor thermos brand name. Basically this still is a high liters per minute like 40 liters per minute a lot of oxygen into the body. Now this method is debated whether every institution is different some institutions say don't do it because it increases aerosolization however we believed it worked if long as we were in a negative pressure room make sure all the precautions and barriers are done and this would prevent us in the setting of COVID progressively getting worse and causing further and further impending respiratory failure in these patients to improve oxygenation and maybe pull them out from the edge. If that didn't work then in case by case elected bases we would use BiPAP or CPAP, the mask, the non-invasive positive pressure ventilation. Fine. COVID is eating away at the lungs and all these experimental treatments that are under clinical trials right now like convalescent plasma, remdesivir, tosylizumab. So these treatments will be ongoing parallel but as they're ongoing we can hydroxychloroquine right so as they're going parallel to this we don't see any improvement in oxygenation what else do we have left but to intubate the patient and that's where the ultimate step comes in from the medical ICU and our oxygenation strategies. So when would we intubate this patient? We've tried all of these methods now we're at an oxygen saturation despite maximum level of treatment including flow land, proning the patient that is a completely different topic but proning has been shown to help. We see a O2 less than 65, SAO2 less than 92% on all on high flow nasal cannula. We see the patients in respiratory distress, respiratory rate greater than 30. CO2 is building up, building up and his patients getting more acidotic is pH. Impending respiratory failure with metabolic variations despite maximum capacity to supplement oxygen is when we would intubate this patient. We don't wait that long until it hits that point. A clinical day-to-day decision and patient-by-patient decision is made to intubate the patient. Fine, COVID is continuing to eat away at the lungs we're unable to oxygenate we've intubated to force air into their lungs to get it into their bloodstream. So this acts and this behaves in a radiographic manner as something called ARDS. ARDS has been around for 60 years now. Now the thing with ARDS is it's a broad umbrella term. It basically says that your lungs are supposed to be like balloons but now in the case of COVID or ARDS they're like cement blocks and that's what we have to try to oxygenate. So over time there's been different trials and strategies that have been accepted. Now one of these strategies, PEEP, which is positive and respiratory pressure is the amount of pressure you push inside the lungs to keep the airways open. That is a very important parameter that we can adjust with a ventilator. Try to increase PEEP, keep the airways open to deliver more oxygen. Tidal volumes, okay. We try to maintain a low tidal volume in these patients to protect it from trauma or barotrauma, pressure trauma. It's a strong recommendation. Other small technicalities we see within mechanical ventilation is plateau pressures. We want to keep it under 30. If we want higher PEEPs we have to determine based on a severity scale, ARDS severity scale, if it's severe we increase PEEP. Other methods have been tried, have not been proven, such as different ventilator strategies such as APRV, inhaled flowland, but overall it's been generally recommended to avoid steroids in these patients. We prone them and we try all these strategies associated with ARDS to increase oxygenation to the lungs. Most of the time we are successful. Most of the time we face a lot of other secondary issues like super infections of bacteria, renal failure, volume overload. There's different things that are happening. All right once again the basic thing comes down to this. We need to get oxygen into the blood stream. Now we have tried everything from nasal cannula to high flow nasal cannula to mechanical ventilation but we are still at a point where we are not oxygenating these patients. What do we do then? And that's when the pathway to the ECMO comes in and this this decision making is usually determined by the ECMO intensivist, an interventional cardiologist or a referring MD, cardiovascular surgery may be a part of the decision making. This is all institution based but our institution protocol Dr. Chatterjee is going to discuss our experiences here. Okay so I'm going to hand it over to him. Hi my name is Shibashi Chatterjee. I'm a cardiovascular surgeon and critical care intensivist as well as the ECMO program director here at Baylor St. Luke's. Today we'll discuss ECMO for respiratory failure in the COVID-19 pandemic and our experience here at Baylor St. Luke's and the Texas Heart Institute. So the ECMO services that we provide here fall into two broad categories. Cardiogenic and respiratory. The most common indications are post cardiotomy, cardiogenic shock, post myocardial infarction, cardiogenic shock, decompensated heart failure, ECMO in the CPR or salvage settings, and those cases to support our VAD and heart transplant patients. On the respiratory side it's typically for ARDS, for pneumonia to support both lung transplant candidates before and lung transplant recipients after their procedure. And the incidence that we use ECMO for respiratory failure currently is about 20%. Over the course of our Baylor St. Luke's experience we typically do somewhere around 120 cases a year in terms of our overall volume. And this you can see represents about a 25 to 30% increase over the course of the last three to four years. What you'll also notice is that about three or four years ago we had very low survival. Approximately one fourth of our patients both in respiratory and cardiogenic reasons actually survived. And at that point when I became program director one of the things we looked at was what were people dying from. And what we found was that we had a high incidence of neurologic in bleeding and complication. So we set about programmatic initiatives to reorganize the program, focus with other specialists in terms of neurologic outcomes, redo our anticoagulation protocols, and improve our patient selection. And you can see over the course of the last three years that our overall survival has jumped from 26 to 47% and our respiratory failure in particular now is over 60% approaching that of the ELSO database. The way we do ECMO is that we have ECMO conventionally in our 32 bed CV recovery ICU. This is where all the cardiac surgery, liver transplant, and mechanical circulatory support patients go to. All of our ECMO is done in the CV recovery room and that's whether it's for cardiogenic shock or for respiratory failure. We begin with nursing at a two to one ratio and then it's one to one nursing. And then finally we start with four to one ECMO specialist which is a perfusionist. And if we go above four ECMO cases and we bring in a second in-house dedicated perfusionist. And there is always an LVAD ECMO staff intensivist in House 24-7. When as we were getting ready for the COVID search we took a lot of instruction not just from international societies like ELSO but also that of other thought leaders around the world in terms of what they were seeing. And I think at this point our first response to the way ECMO was is that there was a lot of concern because the initial reports that came out of China showed a really prohibitively high mortality rate. This is a series of multiple centers only 17 total ECMO cases but you'll see here that the mortality for ECMO cases was 94% and that's compared to a 70% mortality for conventional management. So these patients were highly sick and the truth was in these patients ECMO didn't really seem to make much of a difference. But at this point talking to colleagues both Asian and European colleagues talking to patients that had experienced a pandemic earlier and at a higher intensity level in Seattle, New York, Baltimore and then talking to local other ECMO centers in our area at Houston Methodist and Memorial Hermann we said about trying to rationally formulate guidelines and organize the program within that. And institutionally we used various intensive care unit services CV surgery as well as colleagues in profusion and nursing and respiratory therapy. A critical thing that had to be decided early on was how were we going to be able to provide PPE and provide and care for our providers to make sure that caregivers were not unnecessarily exposed. And we sort of divided an ICU to as you can see a green yellow red zone with various degrees of PPE required in each zone. And so as a result we converted one we actually had one dedicated COVID ICU that was just for ECMO at a maximum we were up to three ICUs, three 12-bit ICUs that were dedicated to ECMO. But various parts of the ICU would be organized into sort of a green safe zone, a yellow sort of transition zone where more PPE was required and then the red or the patient rooms were full on PPE would be required as can be seen here. We were able to bring out some of the equipment not the ECMO circuits themselves to be able to limit the amount of exposure that different care providers would have going into the rooms. So instead we still during this phase during the ECMO surge we still did most of our ECMO in the CV recovery when it was for cardiogenic shock or for post cardiotomy shock. We did however convert 6-culi A to a dedicated COVID ECMO ICU. The same CV recovery ECMO nurses who were down there were dedicated and then they came up to 6A as a dedicated COVID ECMO nurse. None of the nurses switched during shifts but they were all focused within that. We had a dedicated separate ECMO specialist dedicated to the COVID ECMO cases banishing up to four circuits the most we ever had with six circuits at the same time and we still had our 24-7 in-house ECMO intensivist who would be managing all the ECMO cases not just in CV recovery but also in the COVID ICU on top of working with a dedicated intensivist focusing on just the ECMO cases. So this is what our ICU looked like. We had our monitoring outside the room and just like that. The indications we used for ECMO really didn't differ much from the landmark iolia criteria these were guidance and set from from ELSO itself and basically was characterized by refractory hypoxemia or hypercapnia non-responsive to conventional measures. The guidelines that we used that we developed were sort of multidisciplinary and I think that helped to universalize the adoption. In general we were offered ECMO to patients under the age of 60 I should say 60-ish patients who were mechanically ventilated no more than seven days were denied patients in multi-system organ failure or those with significant comorbidities were cases that we avoided as well as prohibitively high REST scores. So how was this decided? This was decided in the ICU the in-house COVID intensivist called the ECMO intensivist and any consultation also required the ECMO director or the critical care or CVICU service line chiefs so that there was a team and sort of a consensus developed at which point the various cannulation procedure procedure list was consulted and then we had a formal call schedule in terms of delineating who would be cannulating and decannulating and managing complications. So this is a little bit of what our experience looks like so over I think the best sort of metric is taking a look at what the number of mechanically ventilated patients were so we had we've had 50 mechanically ventilation patients as of May 20th subsequently 12 of them actually cleared virus and became COVID negative 14 of these patients are currently inpatient and ventilated right now which represents about 30% of the overall cohort. Nine patients so far went on ECMO for respiratory failure you'll see here that represents 18% of the mechanically ventilated cases overall of all the 50 patients 14 have died which represents just under a 30% mortality and about 19 of them have been discharged alive either to home or to LTCH to date. Now this is data we've done nine ECMO cases this is data for seven the last two just sort of were on just the last few days so it's sort of incomplete but I also use this to benchmark ourselves against the extracorporeal life support or organization or also in their registry dedicated to COVID so the average age of our patients was 45 maybe just a little bit younger than the ELSO registry evenly split between men and women the prevalence you can see here of various comorbidities are listed not as huge and it's impressive these aren't patients with a ton of other medical problems by and large and you can see the rest from there. With respect to disease specific demographics on average from the time patients started symptoms to the time they were hospitalized was about five days and from the time symptom onset to intubation was just about six days so once they arrived in the hospital they tended to deteriorate relatively quickly from the time they were intubated in general do we average about within four and a half days of ECMO initiation and our longest was about eight and a half days after initiation of ECMO you can see here where we are relatively ECMO the ELSO registry you can see this was a sick cohort of patients on average people of over 15 a pdf ratio of about 80 and by and large heart function was preserved you can see here the adjunctive measures that were used just about everyone was prone got prostaglandin E2 were paralyzed not steroids and a number of them got various adjuvant therapies within the that were COVID specific in terms of cannulation configuration most of these patients were femfem cannulated three of the patients were cannulated with a dual lumen Avalon catheter one patient actually started out VAV converted to VV and was our longest case he was on for 41 days before he was successfully decannulated I think I wanted to I want to just take a step back here and just make sure that from an anticoagulation standpoint this is where I think it's really important to have program programmatic infrastructure and understanding so we discussed that one of the things that really improved the protocol was to the program was dedicated heparin monitoring protocol that was understood that was coordinated with the help of our keen path colleagues and so we published this data a few years back and we looked here basically the way we managed anticoagulation is typically we would aim for a PTT at least COVID patients typically somewhere between 65 and 75 we would check it every six hours this is consistent with what we had done previously we managed the thromboelastogram the prolonged art time we were in aiming to be therapeutic there the way we did things is when there was discordance between the two the PTT and the tag we sort of used the anti-10 aid level as sort of a tiebreaker to to make sure we were in the right direction we tried to keep antithrombin three levels greater than 50 percent but definitely between third at least greater than 30 to 50 percent and if we suspected hit then we would switch to bi-valorudin for anticoagulation purposes this shows that in general the hit and the PTT and the tag are rarely discordant probably about 35 to 40 percent of the time where they actually concordant which is where the 10 aid becomes important and it sort of underscores why we can't just rely on the PTT in ECMO cases and this was what we published before in terms of our clinical outcomes you can see significantly improved bleeding complications and most dramatically a pretty significant reduction in mortality most importantly so going back to the COVID cases you can see here this is the international ELSA registry as of last week there were about 935 cases worldwide of which we've contributed nine so far and these are outcomes so eight out of nine patients have survived the average runtime was 16 days which is longer than what the ELSA registry reports like I said our longest case was 41 days we had one patient die of an intracranial hemorrhage at eight days and here you can see the other data with the VVA patient so finally I think one of the other things to emphasize is between myself as the ECMO director at Baylor St. Luke's and at Houston Methodist and Memorial Hermann we sort of formed a consortium to be able to like discuss our joint ECMO experience to be able to discuss things that are working things are not working in real time and here you can see that the collaboration between the three centers we've done a total of 34 cases with very good outcomes about an under nine percent mortality outcome and if you compare that to the ELSA registry that has about an 18 percent mortality outcome we've done pretty well so far in terms of practicing ECMO here so with that I think the important points that I really think I'd like to emphasize is that it was respect to COVID ECMO it's really important to be flexible and I think that along those lines it's recognizing that ECMO is a team sport and what it really requires is excellent profusionists people like Rashid Moody and Adam Harshman and all of our colleagues within profusion have done a great job being flexible and working within that working with our nurses to be able to make sure that we can do this at a dedicated way and to do this as safe as possible and in real time I mean there's no playbook for how to do COVID ECMO we had to sort of discover this on the fly and and everybody wanted to do the best job they could for their patients and as well as working with our intensivist colleagues to be able to to work this right away I think one of the unique challenges about this time was that it's important to set the family expectations normally there's always an opportunity for a face-to-face encounter and I think that was probably of the big challenge I think it was really important to either get on the phone and I tried to make it a point to FaceTime at least once or twice so a couple times a week to be able to see that because I think sometimes your nonverbal communication and just being able to look at another person's eyes really tell something and it's certainly one of the biggest challenges but it's something that if you're focused I think it certainly can be done right and I really think this is underscores to get the process right we discussed anticoagulation and I think that the steps that we had taken over the last couple years to get the anticoagulation right really helped in the COVID situation we didn't have bleeding complications because mainly because we kind of knew how to do this right it's important to be deliberate and thoughtful remember every time you get a lab test you're sending other people into you know to risk and to exposure so I think we were thoughtful and deliberate about that and I think that's important and with that that's essentially it so we'd be happy to entertain any questions