Thank you, good afternoon everybody. Thank you for joining us today, my name is Amira Mohamed. I'm going to be talking, I'm going to be doing the SESAM Year in Review. I'm going to start by saying I have no conflict of interest and I'm going to be going over three studies today. I work mostly in the medical ICU, so my main focus is going to be in acute respiratory failure, specifically in these patients who are intubated. I'm going to start by talking on a study that happens before intubation and how to maintain a patient's heart rate while inducing and during the intubation itself, followed by another study after the patient is on the ventilator and what are the oxygen targets for these patients, what is the best oxygen target. And finally, after extubating patients and how to best support them, whether it's with whichever machines, we're going to talk a little bit about high-flow nasal cannula and non-invasive ventilation. So the first study is the effect of fluid bolus administration on cardiovascular collapse among critically ill patients undergoing endotracheal intubation. This was published in June of 2022. So before I go into the details of the study, I wanted to go a little bit over what we already know about giving fluid boluses during induction. So we already know intubating in the ICU is a high-risk procedure. 25% to 40% of these patients have been looked at and we have shown that these patients become hypotensive during induction and during intubation. But what is the best way to manage that? We know that most likely the reason that they become hypotensive during intubation is multifactorial. So it could be because of the medications that we're giving, causing vasodilatation, decreasing the preload, and therefore decreasing the cardiac output. But also they might be slightly hypovolemic to begin with. There have been multiple studies done on this, multiple studies looking at giving fluids during intubation, and these studies really showed no difference. So it really does not improve outcome, does not change mortality, whether or not you give fluids when you're inducing. However, there was a slight improvement or a slight trend towards... Thank you. There is a slight trend towards improved mortality in patients who were pre-oxygenated with positive pressure ventilation, meaning that if a patient was placed on BiPAP or any sort of positive pressure, such as bag mask ventilation, during induction, the increased intrathoracic pressure would cause decreased preload, therefore decreased cardiac output, they're more likely to be hypotensive, and there's a slight trend of them having a positive outcome if you give them fluids during that time. So despite all of this evidence, we still are giving fluids to about 40% to 50% of our patients during intubation, and the guidelines still recommend, a lot of guidelines recommend giving fluids during induction. What the authors here wanted to do or what they were trying to search is, is this beneficial, and specifically, is it beneficial when we pre-oxygenate with positive pressure ventilation? Should we be giving these patients any fluids? So they had a little bit over 1,000 patients, and all of these patients were induced and given positive pressure ventilation during induction, so either non-invasive ventilation or bag mask ventilation. They ended up dividing the patients into two. They gave a 500cc bolus of isotonic crystalloid solution to one group and giving no fluids to the other group. Now I have to note that they actually excluded about 15% of patients because they were called emergent intubations. A lot of the patients in my ICU are emergent intubations, so I find it very hard to generalize, but they did exclude about 15% of the total patients who were intubated. This was done over in 11 ICUs, and their primary outcome was cardiovascular collapse. So they looked at systolic blood pressure of less than 65, new vasopressor support or an increase in vasopressor support within two minutes of induction, and finally they also looked at death and cardiac arrest. And what they found is there was no difference between the two groups. So they found that giving a fluid bolus did not really improve the outcome in these patients who received positive pressure during intubation. But like I said, it's very hard to generalize this study just because they excluded a large amount of patients, and I'm not sure why they were excluded. They also excluded patients where the clinician felt strongly about giving fluids, where the clinician did not feel comfortable randomizing this patient, because we already know that about 40% to 50% of our patients receive fluids during intubation. They also did not really talk about the use of induction agents. I know a lot of ICUs that still use propofol. I know etomidate is very popular in our ICU, but they really did not talk about the effect of choice of induction agent that was deft to the clinician. So still a lot of questions from these studies, but what it does tell me is that I will not be universally giving fluids when inducing patients. The second study is oxygen saturation targets for critically ill adults receiving mechanical ventilation. So oxygen targets I think has been a very controversial topic for some time. I know in our ICU we have a lot of people who lean more towards a lower O2 sat, kind of more at 92%, 90% to 92%. Their goal is to avoid tissue hyperoxia, oxidative damage, inflammation, any of the hyperoxia complications. We also have people aiming for a higher O2 sat, kind of more 98%, and they're trying to avoid hypoxemia, tissue hypoxia, and lactic acidosis. There's been randomized studies comparing high O2 sat to low O2 sat, and there's really no difference between the two. But there haven't been any randomized studies looking at intermediate O2 sat, about 94% to 96%. Observational studies have shown that it's more of a U-shaped curve, meaning that if low and high are equal, there is maybe a slight suggestion that intermediate O2 sat target might be beneficial. And this is what this trial was trying to prove. This is the first trial that's randomized that's going to be comparing intermediate to both low and high O2 sat targets. So what they did is that they looked at all patients intubated in the emergency room and in the intensive care unit, and they included all mechanically ventilated adults. This is a very generalizable study in that they only excluded 1% of patients, and they started as soon as the intubation happened. So it was a very well-done study. Their oxygen targets were low, medium, or intermediate, and high. So they looked at 88% to 92%. Their median there was 90%. They looked at 92% to 96%. The median there was 94%. And they looked at 96% to 100%, where the median was 98%. They did something called a cluster randomized trial, meaning that they had a two-month cluster period. So every two months, they would decide what the target oxygen is going to be for the whole group. So, for example, for the first two months, their oxygen target is going to be the low target. For the second two months, they're going to switch everybody to an intermediate target. For the third two months, they're going to switch everybody to a high O2 target. And that way they were alternating for a total of 18 clusters or 36 months. So the way that the patient would be removed from the study is, A, if they're extubated, B, if their cluster period has ended, and then they would switch to a different cluster, or C, if they're transferred out of the ICU that's enrolled. This is a very large study. It included a little bit over 2,500 patients. What they found is there was actually no difference between the low, intermediate, and high group. They looked at their primary outcome was ventilator-free days, and they found no difference in the ventilator-free days. They also looked at the incidence of MIs, the incidence of strokes, the incidence of pneumothoraces, things that we would suspect would happen in low oxygen saturation or too high of oxygen saturation. And there was no difference between any of the targets that they had. The biggest thing about this study is after this came the controversy of pulse oximetry and whether they are accurate or not, especially in darker-skinned individuals. And it's very hard to generalize a study that only focused on pulse oximetry, which this study did. So they did not really depend on blood gases, unless they felt that the pulse oximeter was, for whatever reason, is inaccurate. Their population was less than 15% black. And I think that's, I work in the Bronx. We definitely have more than 15% black and Hispanic patients, so it's very hard for me to generalize the study. However, it is reassuring to know that there's not much difference between the population. Finally, there's this interesting study about the effect of post-extubation noninvasive ventilation with active humidification versus high-flow nasal cannula on reintubation. This is for patients in very high risk for extubation failure. So what do we already know about the rates of extubation failures? What we already know is, for example, in our ICU, when we usually extubate patients, we extubate them to an aerosolized face mask. We don't really suspect most of our patients don't get reintubated. Our reintubation rates are not that high. However, there is a subset of patients that's high risk. We have predefined high-risk patients, patients who are intubated for hypercapnia, patients who are morbidly obese. These patients who we suspect have a little bit of a higher risk of getting reintubated, these patients end up on noninvasive ventilation. So most of the time I do aerosol, but for certain patients, I'm doing noninvasive. This is based on previous studies that showed that putting these patients on noninvasive ventilation makes them at less risk of getting reintubated. More recently, there are studies that compared a noninvasive ventilation to high-flow nasal cannula after extubation in these high-risk patients, and they found no difference. So now people are saying that maybe we should just use high-flow nasal cannula just as we're using noninvasive ventilation in these high-risk patients, and we're still not going to increase the rate of reintubation. So the question that the authors here had was, what if somebody has multiple risk factors? What if they're not only hypercapnic respiratory failure, but they're hypercapnic, and they're obese, and they're over 65 years of age with multiple comorbidities, and they have been intubated for 12 or more days? So they have multiple risk factors. Is high-flow nasal cannula really equivalent to noninvasive ventilation in these patients? So they wanted to look at specifically patients with multiple risk factors. They also noticed that in a lot of the previous studies, patients did not really keep the noninvasive ventilation on for that long, sometimes only 8 out of 24 hours. They felt very uncomfortable. So they wanted to look at active humidification of noninvasive ventilation. Are patients going to be more comfortable on that? Are they more likely to keep it on? So this study, they looked at all adult patients intubated for over 24 hours who had more than four risk factors for reintubation. And we already talked a little bit about what the risk factors are. They divided them into noninvasive ventilation or high-flow nasal cannula. For the noninvasive ventilation, they used active humidification. And they ended up with a little bit over 170 patients. This was done in two hospitals in Spain. They actually found a difference between the two. They found that the patients who were placed on noninvasive mechanical ventilation did better. They were less likely to get reintubated. Not only that, if you look at the graph, at five days, patients on high-flow nasal cannula were still getting reintubated. So five days later, when it looks like the noninvasive mechanical ventilation patients were out of the woods, the high-flow nasal cannula patients were still getting reintubated. So that was very significant. The second thing is that they noticed that compared to previous studies, their patients reported being more comfortable with active humidification and were able to keep—I've never had a patient keep the BiPAP on for like a week. Their patients kept their BiPAPs on for a week. And they reported feeling a lot more comfortable. So their take-home points were, first of all, we need to redefine high risk for reintubation. One risk factor may not be that high, but somebody with two, three, four risk factors for reintubation, these patients are a completely different subset. Secondly, if they have multiple risk factors, high-flow nasal cannula, we previously reported was noninferior. It may not be noninferior in these patients. And finally, if you're going to use a BiPAP machine, try to use active humidification with it. I think that's the big takeaway for me, is that I'm going to try to encourage my respiratory therapists to use active humidification whenever they're using a BiPAP machine. And that's it. Thank you. Applause.

patient care

ICU

fluid bolus administration

oxygen saturation targets

non-invasive ventilation