SCCM Resource Library-Sucking Wind: Support Strategies Beyond the Ventilator

Video Transcription

Hi, everybody. It's a pleasure to be here. My name is Brian Fuller. I'm an Associate Professor of Anesthesiology and Critical Care Medicine and Emergency Medicine at Washington  University in St. Louis. I'm pleased to be moderating this session, which is called Sucking  Wind, Support Strategies Beyond the Ventilator. We're going to hit three topics today. The first  one is going to be optimizing high-flow oxygen. The second one is optimizing non-invasive  ventilation. And the last but not least will be alternative strategies, witchcraft, and wizardry.  Hello, everyone. I'm Skyler Lentz. I'm a Critical Care Physician and Emergency Physician at the  University of Vermont Medical Center. And I'm here to talk to you today about optimizing high-flow  nasal oxygen in the patient with acute hypoxemic respiratory failure. I have no disclosures.  The learning objectives, what we're going to go over today, we're going to describe the optimization strategies for the support of the hypoxemic patient with high-flow nasal oxygen.  We'll talk about the therapeutic options for non-invasive support of the patient with hypoxemia  and respiratory failure progressing to possible intubation. We'll appraise the data supporting  high-flow nasal oxygen for the peri-intubation patient. First of all, it's important to point  out that high-flow nasal oxygen is a special device. It's not just a simple nasal cannula cranked up high. This is a device that takes compressed medical air into a flow meter and  then an air and oxygen blunder. And that mixture of air and oxygen is then delivered to a heater  and humidifier before being delivered to your patient through a specialized nasal cannula.  There are many different devices and setups that can do this. In fact, some ICU ventilators can use  their own heating and humidification, can use their own heat and humidification to deliver  high-flow nasal oxygen for support. These are some of the different nasal cannulas available  on the market. The one on the left is called Optiflow. It's one that uses a large-bore nasal  cannula. The one on the right is a smaller-bore nasal cannula that the company calls high-velocity  nasal insufflation. It delivers flow at a higher velocity. There's been no studies that I've seen  to say that one is more superior than the other. It really comes down to what's available at your  institution. The settings. The most important is the flow. Usually for adults, this is somewhere  between 30 and 60 liters per minute. And when setting a patient up on this, some may start in  the middle range, say around 30 liters per minute, and increase from there depending on the patient's  response. Others may just start at 60 liters per minute on the maximal settings and see how  your patient tolerates it and decrease it from there. The next thing that you can set is the  temperature that's being delivered. You can adjust it lower or to body temperature depending on your  patient's preference. You can also adjust the FiO2. How does it work? Why is it so special?  Well, it allows you to titrate oxygen and it's a better oxygen delivery device than other low-flow  oxygen devices. It allows the heat and humidification to promote mucociliary function so that your patient can cough and clear the secretions. It also washes out the dead space  of the nasopharynx, allowing for CO2 clearance. And it also generates some degree of positive  pressure and that causes alveolar recruitment. It can also reduce the work of breathing. In fact, in studies of healthy volunteers set up on high-flow nasal oxygen, they found that  they can reduce their respiratory rate to as low as five per minute, so they could really reduce  their minute ventilation and work of breathing without causing hypercapnia. This suggests that  although minute ventilation and work of breathing is reduced, alveolar minute ventilation is  maintained, and this can really help your patient in distress. This can generate positive pressure.  In studies, they've shown it to be about one centimeter of water for every 10 liters per  minute of flow. So if your patient's on 60 liters per minute of flow, it's generating about six to  eight of mean airway pressure. And in studies of impedance tomography, they've shown an increase  in end-expiratory volume, suggesting alveolar recruitment, helping again with oxygenation, and potentially reducing lung injury through these effects. The other thing the high-flow  devices can do is deliver oxygen more effectively. They can deliver a higher FIO2 to your patient.  Patients in distress are breathing at a very high peak inspiratory flow rate, and the low-flow devices  like the non-breather set to 15 liters per minute just can't keep up with this inspiratory flow,  and it causes the mixture of ambient air with those low-flow devices. Whereas with the high-flow  devices, they can begin to approximate and match the patient's desired inspiratory flow and deliver a higher effective FIO2. So those are the physiologic benefits, but what are the  evidence and guidelines say to support its use? This was published in late 2020. It's a practice  guideline statement from a working group from the European Society of Intensive Care Medicine,  published in the Intensive Care Medicine Journal, and they give a strong recommendation for high-flow  nasal oxygen for acute hypoxemic respiratory failure. When they examined this in the peri-intubation  and pre-oxygen phase, they made no recommendation for or against its use based on the limited evidence.  This working group also performed a meta-analysis to look for the evidence in acute hypoxemic respiratory failure, and what they found was a decreased need for intubation  when using high-flow nasal oxygen when compared to conventional oxygen therapy. They also found a reduced escalation of respiratory support  when using high-flow nasal oxygen. However, they did not find any evidence of reduced mortality.  So it seems pretty clear that high-flow nasal oxygen is superior to conventional oxygen, but what about the other modalities like non-invasive positive pressure?  The FLORALI trial, published in the New England Journal in 2015, was a landmark trial for many  of us in the use of high-flow nasal oxygen in our practice. They took 310 patients with  acute hypoxemic respiratory failure and P to F ratios of less than 300 without hypercapnia and  without suspected cardiogenic pulmonary edema. Most of the patients had pneumonia and many met  the criteria for ARDS, and they split these patients up into three groups. One group was high-flow nasal oxygen. The other was just conventional oxygen therapy and standard  oxygen therapy. The other was non-invasive positive pressure through a tight-fitting face  mask in bi-level settings. And what they found, what their primary outcome was, was the rate of  intubation. And across the entire group, they found no reduction in intubation. However, in  a subgroup analysis, those with more moderate to severe hypoxemia with P to F ratios of less than  200, high-flow nasal oxygen reduced the intubation rate in this group. High-flow nasal oxygen also  improved 90-day mortality when compared to the other two. And what was eye-opening to many of us  in our practice is that the non-invasive positive pressure group had the highest intubation rates and mortality rates. It's possible that non-invasive positive pressure is causing  high transpulmonary pressures and high injurious tidal volumes, perpetuating and worsening lung  injury, and that high-flow nasal oxygen may actually be superior to non-invasive positive pressure when used in this patient group. Again, most of them had pneumonia.  Now, later in 2020, there was a meta-analysis published in JAMA, again comparing high-flow  nasal oxygen to other therapies. And what they found, again, is that high-flow nasal oxygen reduced the risk of intubation when compared to conventional oxygen therapy but was not  associated with a lower mortality. When they compared high-flow nasal oxygen with NIPPV  through a face mask, there was no difference in mortality when comparing the two.  And now when they compared high-flow nasal oxygen with non-invasive through a helmet interface,  there was a reduced risk of mortality with the helmet. There seems to be something special about  the helmet interface, but it's not available to me at my institution, so it limits its use  due to lack of availability. So the bottom line from all this is that high-flow nasal oxygen,  acute hypoxemic failure, reduces the rate of intubation and is superior to conventional oxygen  therapy. When comparing high-flow nasal oxygen to non-invasive positive pressure for this use,  it requires further study. But I think that the FLORALI trial gives us some insight here to say those with pneumonia, those meeting the inclusion criteria of the FLORALI trial,  high-flow nasal oxygen may be a better choice than non-invasive positive pressure. But we do  need more studies looking more at the helmet interface in its comparison to high-flow nasal  oxygen in particular. Now this is my reminder that if I have a patient with hypoxemic respiratory  failure, I place them on high-flow nasal oxygen, I need to watch them and reassess them. I need to  make sure that they're responding to my therapy. If I started them on a lower flow like 30 liters  per minute and they still don't look good, their oxygenation and work of breathing hasn't improved, I'll increase the flow. I'll reassess them and see how they're responding.  And we need to keep in mind that 30 to 40 percent of patients may fail that we start on this and  require intubation. And we don't want to delay that intubation any longer than we have to  because it turns out that a delay in intubation may be harmful. This was a retrospective study  published in 2015 looking at those started on high-flow nasal oxygen and those that were intubated early versus those that were intubated late. And they broke this down into less or  greater than 48 hours. Those that were intubated late had a higher ICU mortality than those  intubated early. But if you dig deeper into the details here, the mean intubation time in the  early group was 10 hours, the mean intubation group in the late group was 126 hours. So really  this was a study looking at early intubation versus very late intubation. Later a post-hoc analysis of the Florale trial that we discussed earlier did not demonstrate an increase in  mortality with time to intubation. But it's important to point out that the mean time to  intubation in that group was less than 24 hours. What this suggests to me is that within 12 to 24  hours I should be making a decision. Is my patient going to benefit from continued use of high-flow  nasal oxygen or are they going to require intubation? And I should consider carefully whether I continue this therapy or proceed to intubation.  And what we're all trying to balance at the bedside is we're trying to prevent an avoidable  intubation in the ill effects of mechanical ventilation, sedation. But we don't want to delay intubation. We don't want to delay a lung protective strategy with controlled tidal  lines and adequate PEEP, and we don't want to perpetuate the potential risk of patient self-inflicted lung injury. So at the bedside we're trying to balance these two. Now wouldn't  it be nice if we could predict failure? Well if we could predict failure that would be great. We  could intubate those who need it and continue therapy for those who don't. So this was a  post-hoc analysis of the Florale trial and they found no respiratory variable to predict failure  of high-flow nasal oxygen. The only thing that was associated was an increase in heart rate one  hour after initiation, but this wasn't a robust or very helpful finding.  There's a group that developed a ROX index in predicting failure of high-flow nasal oxygen and this could be helpful at the bedside. What the ROX index is is pulse oximetry,  so pulse ox divided by FiO2 over the respiratory rate. And they found that a ROX index of greater  than 4.88 is associated with success of high-flow nasal oxygen and avoidance of intubation,  whereas scores of 2.85 at two hours, 3.47 at six hours, and 3.85 at 12 hours predicted failure of  high-flow nasal oxygen and later intubation. Now what the authors suggest here is that at 12 hours  we make a decision. Most of our patients will fail between 12 and 24 hours, so this is a good  time point to evaluate this non-invasive support or the support of high-flow nasal oxygen. And if the ROX index is greater than 4.88, that predicts success of this therapy,  whereas if the ROX index is less than 3.85, failure is likely in consideration of early intubation  and one should consider early intubation. Now it's important to point out in the prospective  cohort where the ROX index was validated, most of the patients in that group had pneumonia,  so again this may be helpful in your patient who has pneumonia to use this and to help predict  their outcome. For me predicting failure, I don't think there's a score that can replace  my clinical judgment at the bedside, but failure to improve despite maximal settings, failure to  improve work of breathing, failure to improve oxygenation is concerning and should prompt consideration of stepping up the therapy to invasive mechanical ventilation.  Now if you're moving towards intubation, high-flow nasal oxygen can help with pre-oxygenation and can  help in that peri-intubation phase of care. High-flow nasal oxygen is at least as good as conventional pre-oxygenation strategies. It's at least as good as the non-rebreather mask  and other standard oxygen devices. So my recommendation is to maximize the settings, crank it up to 60 liters a minute, 100 percent FiO2, and leave high-flow nasal oxygen in place  if already in use. Now high-flow nasal oxygen was compared to non-invasive positive pressure  for pre-oxygenation and what one study found was that non-invasive positive pressure may be better  in moderate to severe hypoxemia and in preventing severe desaturations less than 80 percent.  So what this means to me is if my patient has more severe hypoxemia, non-invasive positive  pressure may be better at recruitment, better at pre-oxygenation, and I should consider that in  this patient population. But if I already have high-flow in place, what I might do is recruit them, pre-oxygenate them with non-invasive positive pressure, then during laryngoscopy  I may replace the high-flow device for ongoing apneic oxygenation and use the two in combination.  So in summary, high-flow nasal oxygen reduces intubation rates when compared to conventional  oxygen therapy for acute hypoxemic respiratory failure and should be a first-line therapy  in this group of patients. What's a little bit harder to figure out is who benefits more from  non-invasive positive pressure. The FLAIR-LY trial gives us a hint that those with pneumonia,  there might be a greater benefit of using high-flow nasal cannula in this group, but this  requires further study, particularly if you have the helmet interface available. I would love to  see a study later on comparing helmet to high-flow nasal oxygen in patients with pneumonia and  hypoxemic failure. The other thing that we have to keep in mind is we should anticipate failure and  not delay appropriate invasive mechanical ventilation. We don't want to delay intubation  and potentially cause harm. Now if as you're moving towards intubation, high-flow nasal oxygen  is good for pre-oxygenation alone or in combination with non-invasive positive pressure. Thank you for listening. I'm happy to take any questions. Hi, my name is Keith Lamb. I am a  respiratory therapist and I work for the Trauma Service at the University of Virginia in Charlottesville,  Virginia. Today I am going to talk for a few minutes about optimizing non-invasive ventilation.  In terms of disclosure, I have one currently and that is that I am on the advisory board and have  on the advisory board and have received a travel stipend and honorary from Fisher-Peikman.  We have quite a few talking points that I want to try to get through in this short period of time. I want to answer the question of what really constitutes non-invasive ventilation.  What are the indications for non-invasive ventilation? What are the contraindications?  If there are some basically approaches to implementing non-invasive ventilation  interfaces, conclusion, and discussion period.  So what is non-invasive ventilation? The literal definition of non-invasive ventilation  is respiratory support to support ventilation by using an interface with the patient's native  airway. So non-invasive ventilation excludes any ventilation support that includes an artificial  airway like an endotracheal tube or tracheostomy tube. Things that qualify, and some of this  some of this is ambiguous. It's not clear-cut and some of it is not. So continuous positive airway pressure or CPAP would be a non-invasive ventilation support.  Bi-level positive airway pressure or BiPAP is certainly one. High flow nasal cannula  high flow nasal cannula is increasingly referred to in the literature as a type of non-invasive  ventilation. And one of the reasons for that, I'll get to that shortly, but one of the reasons is certainly that it doesn't fit neatly into anything else. It doesn't fit neatly into  just supplemental oxygen support and so we'll talk a little more about its potential influence  on ventilation. And finally negative pressure ventilation which which has been around for a  very long time. The old iron lungs and polio support was one type but it's come a long way  and although it hasn't gained a lot of traction inside the hospital yet it certainly is an option  and one that might be attractive in some patients that that might not be able to receive  or be managed with non-invasive ventilation and some of the other modalities.  So what are the indications for non-invasive ventilation?  Certainly gas exchange abnormalities like hypoxemia and hypercarbia  result in work of breathing from from respiratory failure in the hypoxemic or hypercarbic patient. Some neuromuscular patients that have neuromuscular disease  particularly acute changes where non-invasive ventilation might get them through the initial  phase until definitive treatment has has been determined and implemented. Upper airway soft  tissue obstruction, nocturnal hypoventilation syndrome, obstructive sleep apnea, those types of things can get can be mitigated by CPAP or other non-invasive ventilation strategies.  There are certainly some contraindications to non-invasive ventilation. Those who of us who practice in critical care can tell you that sometimes it's just the eyeball factor in a  patient that is just you know too too deep into their acute respiratory failure that  it's just sort of obvious to the team that that patient needs to be invasively ventilated that that patient needs to be invasively ventilated but it's not always it's not always  really intuitive. Mental status, someone who can't protect their their own airway, if somebody's got  a real low mental status or a neurologic insult and their airway protective reflexes, cough and  gag refluxes, are not intact then that's certainly somebody who you may not be able to effectively  support with non-invasive approaches. Issues with interface, most of these non-invasive approaches  include a an interface that that comes in contact with the face so patients who have  maybe Laforte fractures of the face, significant other significant fractures, mandibular fractures  or even burns, burns on their face, wounds on their significant wounds on their face that can't be  sort of stepped around, those patients might not be good candidates for non-invasive  ventilation. Some upper GI issues like you know if a patient's feeling nauseous, a horrible  combination is a patient that's nauseous and their neuro status is not great then they may be unable  to remove the interface if they if they are going to vomit and that's certainly not best case  scenario for non-invasive ventilation either. There is an esophageal sphincter opening pressure  that may be somewhere around 25 centimeters of water and some literature describes that  so if it's possible that you know that the non-invasive pressure may influence that and  cause large amounts of air to be insufflated into the GI system. Gastric tubes that  either nasogastric tubes or orogastric tubes may get in the way of using interfaces for non-invasive ventilation so those things need to be thought about also.  So approaches to non-invasive ventilation, what do we use to provide non-invasive ventilation?  Modern day flow generators, some of our pre-hospital folks have these sort of flow generators that will generate CPAP for those patients they pick up and significant cardiogenic  pulmonary edema. We have specifically designed equipment like BiPAP machines, machines that are  designed to provide non-invasive ventilation and in some sometimes invasive ventilation.  ICU ventilators, most modern day ICU ventilators can be adapted to non-invasive ventilation. It's  a matter of the machine acclimating to a certain amount of leak that's going to be present with non-invasive. The two major components of non-invasive ventilation are inspiratory  positive airway pressure and expiratory positive airway pressure and so IPAP or the inspiratory pressure minus IPAP or the expiratory pressure is the driving pressure delta P.  Sometimes the clinician will set a backup rate on non-invasive ventilation so that  in case the patient doesn't, their spontaneous rate drops below whatever it is thought to be effective then the machine will go ahead and pick up where the patient left off.  So when implementing non-invasive ventilation for worker breathing or distress, then the delta P  can be increased by just increasing the IPAP. If the patient's primary problem is hypoxemic respiratory failure then the IPAP can be increased, keeping in mind that in some machines  the driving pressure will stay the same when you increase the E-PAP, and in some machines, increasing the E-PAP will actually reduce the driving pressure  because it doesn't concomitantly increase the I-PAP. Monitor progress of lack or lack of progress carefully, and what I mean by this is that  we sometimes will be optimistic about a patient who may have really needed to be invasively ventilated to try to avoid all the deleterious effects that invasive ventilation may come  along with, so these patients certainly need to be monitored at least as well as anybody else.  High flow nasal cannula, I mentioned that some people will consider this non-invasive support and some people, or non-invasive ventilation, some people won't.  You get about a centimeter of water pressure per 10 liters of flow of positive airway pressure,  so because of that, you may improve compliance, and as a result of improving compliance, the patient may ventilate more effectively.  In addition to that, that high flow, which goes anywhere from low levels to 60 liters per minute, depending upon the equipment, washes out dead space, and if you wash out  anatomical dead space, then the patient re-breathes less carbon dioxide, and as a result, may have lower levels of plasma CO2.  Under pressure ventilation, like I said, hasn't gained a lot of traction, but in patients that can't tolerate the interface, that might be an option.  Something to also remember in non-invasive ventilation, that the same protective rules apply, so volutrauma, barotrauma, toxic levels of FIM2 entrainment, all of those may cause  biotrauma, and in fact, the EPAP, which is almost synonymous with PEEP, may also prevent adalectrauma, which is a big player in patients with significant respiratory failure, and  going on to develop a secondary inflammatory process that may, certainly may influence their outcome.  Some of the interfaces here, you can see, all the ones on the top there are masks that may be used to interface with the patient.  I think the key here is that there's some give and take, so there are certainly masks that are probably better at ventilating patients, like full face masks, or nasal masks, and  this helmet that's gained some traction during the COVID pandemic here in the United States.  These will certainly ventilate patients better, but they won't ventilate patients better if  they're not tolerant or they're not compliant in the therapy, so sometimes you have to give away a little performance to get anything, and so that's important to remember.  This is a chest QRS for the negative pressure ventilation on the bottom there, and again,  so somebody who has facial fractures or may not be able to tolerate a face mask or interface of any sort, this may be an option.  So in sort of conclusion, noninvasive ventilation may prevent intubation and complex sequelae,  so it's very important to understand that even though you're not invasively ventilating somebody with this technology, the same rules still apply, and so those protective rules  that apply would be try to use the lowest FIO2 possible, try to use tidal volume that seemed appropriate and safe based on predicted body weight, try to monitor driving pressures  that we know there's good literature to support deleterious effect from higher driving pressures, and so just sort of keep that in mind.  Drop the FIO2 as much as possible, increase the EPAP in order to do that. Patient compliance to the therapy is paramount.  If they're not going to be compliant, that's probably the biggest reason why this approach fails in acute respiratory failure is the patient's inability to be compliant with  the interface and the therapy itself. So in terms of why people fail and then wind up getting intubated, just as often as it  is because of respiratory failure getting worse, it's also because of the patient not being compliant with the therapy.  The patient must be monitored carefully in order to not miss the need to provide definitive support,  and what that means is oftentimes with noninvasive ventilation, we may mask the symptomology,  but we haven't done anything to sort of address the respiratory failure, and so that patient may be…their underlying condition may be getting worse, and so we need to monitor them  closely in order to make sure that we don't miss the opportunity to provide definitive support, whatever that might be. And so that being said, I appreciate you listening to me.  My email address is on this slide if you would like to contact me or reach out to me for any reason, and I thank you all.  Hi, I'm Kit Tainter, and we're going to talk about alternative strategies, witchcraft, and wizardry. First of all, none of this is witchcraft or wizardry.  I'm not a wizard, and you can do any of these things on your own, but maybe some of them will be new and seem like magic.  Since you've already heard about high-flow nasal cannula and noninvasive ventilation, I guess we can call this ways to stay off the ventilator.  And maybe to make it even more interesting, we can make it into a top ten list. I know you're only going to learn three things from this talk, but maybe these three things  will be different for everybody, so I'll give you ten to pick from. Ten things in 20 minutes, a little ambitious, so I'll move quickly.  So if you're watching at one and a half speed, you might want to slow down. But if you have this recorded, you can rewatch anything particularly interesting.  And way of disclosure, I have no real conflict of interest. I did participate in a medical advisory board earlier this year for Viair, who makes respiratory  support devices, and a couple of them are included in this talk, but I don't get any royalties. In fact, I still haven't even received my check from the advisory board.  This is a bit like choosing whether you want to manage your patient with respiratory failure the easy way or the hard way.  In most cases when you're contemplating mechanical ventilation, avoiding it is going to take more effort than just intubating them. But that doesn't mean there isn't a benefit.  Avoiding intubation may mean less sedation, less delirium, or shorter ICU stay. I'm not going to claim that any of these things have a proven mortality benefit per se, but  I will try to share some evidence when available and suggest that a lack of evidence for benefit  is not the same as an evidence for a lack of benefit. So let's get started. Number 10, diuresis. We know that a positive fluid balance may be associated with increased lung injury.  We can debate the utility of using hyper-oncotic albumin to augment diuresis and mobilize interstitial fluid.  I'm sure we've all done it, and it definitely seems to work sometimes, especially for those with a low albumin level.  But whether it's worth the cost, I can't say for sure, and our pharmacist doesn't always think so.  How about something a little cheaper, maybe specifically designed for osmotic diuresis, like Manitol? Or how about using hypertonic saline?  It's shown some positive effect in heart failure patients in several trials. This meta-analysis showed a mortality benefit and a shorter length of stay.  In addition, they showed more effective diuresis with weight loss with hypertonic saline and an improvement in renal function.  Another more recent study retrospectively looked at 58 cases using 150 milliliters of 3% saline to augment loop diuretic performance and found that it did.  And it helped to normalize sodium and chloride and lowered creatinine. So it turns out that both hyper- and hypochloremia are associated with diuretic resistance, which  may explain some of the mechanism for this effect. Perhaps treating hypochloremic patients with hypertonic saline sort of kills two birds  with one stone, augmenting osmotic drag from the interstitium and normalizing a low chloride. And maybe it makes sense to use hypertonic bicarb to treat hyperchloremic patients with  the same rationale and absolutely no data. Number nine, optimize your patient positioning to improve respiratory dynamics.  I don't know how many times I've been called in for acute respiratory failure and I see this. Why does this seem to be our default position when somebody is in any kind of distress?  This is just about the worst position possible for a patient who has trouble breathing. In an upright position, gravity can help the diaphragm contract.  We no longer have to overcome the weight of the chest wall or abdomen during inspiration. There's less area of dependent lung and better VQ matching.  Just about everything about breathing is better in an upright position, which is why this is usually the position we end up with when we feel short of breath.  And of course, the last thing you want to do is lay them flat when they're apneic during laryngoscopy.  At least a couple of studies have suggested that you can actually get a better view in a partially upright position and it takes them longer to desaturate, which is why I've  started doing pretty much all of my intubations in an upright or semi-upright position. And upright does not necessarily mean folded in half, especially in patients with a large  abdomen. This can compromise their diaphragmatic movement. You may want to go for more of a ramped position like this.  Or think about any other way you can relieve the abdomen pushing up into their chest. Maybe a paracentesis or NG decompression to help their work of breathing and decrease  their risk for aspiration. And then, of course, most of us have become very familiar with pronation recently, basically the opposite of supine.  The idea here is that alternating the dependent portion of the lung improves aeration, promotes more blood flow to the aerated portion of the lung.  It definitely works to improve gas exchange. There's some conflicting evidence about whether it improves survival, but I think when it's  done well without causing extubation or decannulation, it can provide a lot of benefit, even in patients on ECMO. And you don't have to be intubated to change position.  We're doing the awake proning rotisserie dance pretty much routinely now with our COVID patients before they get intubated. Number eight, lung expansion.  We have several things to improve lung expansion. The most basic is the incentive spirometer. I'm sure we've all seen these, usually by the window out of reach from the patient.  They depend on patient effort and cooperation. Usually when you hand this to someone, if they are not delirious, their first instinct is to blow into it.  And of course, we really haven't proven that these even do anything, but they're pretty benign and I definitely encourage their use.  If the patient can't or won't use the incentive spirometer, there are a variety of positive expiratory pressure devices available.  I intentionally did not include any trade names for these products. They can usually be used with a mouthpiece or with a mask. Here are a few more.  Number seven, another thing our respiratory therapist friends especially can help us with, secretion clearance. There are a variety of devices available again.  These work with some sort of vibratory apparatus, which creates intermittent airway resistance. Here are a few more, and yes, that one in the middle is an airway device.  Then there are electronic percussion devices as handheld pieces or of course as a vest. And some of our hospital beds can perform vibratory percussive therapy, just like these  beds we used to see in some cheap motels. Then there's the good old fashioned way, manual percussive therapy.  Airway suctioning can help, especially when there's a weak cough or impaired sensation.  And there are oscillatory devices, which mechanically create pulsatile airway pressure, which can also be done in ventilated patients.  And finally, everybody's favorite, the cough assist machine. This can be pretty uncomfortable for the patient because it creates such violent changes in  airway pressure, so sometimes it takes a little convincing, but it may still be better than an endotracheal tube.  Finally there are medical therapies we can consider to help with secretions, anticholinergics,  mucolytics, expectorants, and things like inhaled saline to moisten secretions or promote cough, each with their own advantages and disadvantages.  Number six, maintain an open airway. Of course we're all familiar with oropharyngeal, nasopharyngeal airways in various sizes and colors.  When you think about the maneuvers we do to keep the airway open, can you think of anything else that does this to your chin?  Now usually we think about C collars making the airway more difficult to manage, but sometimes,  it can help support your chin in a straight position, especially if you look like this. Maybe all they need is something to keep their head up.  Rather than a C collar, I kind of think about it more like this. It lets you keep someone sitting up who maybe doesn't have a lot of ability to keep their head straight.  And there are some collars that even have a little jaw thrust mechanism built right in.  Again, this is not necessarily a solution to your problem, but if you need your hands free and can't stand at the bedside doing a chin tilt for the next three hours while  your patient sobers up, this might be something to consider. Okay, nutrition is not the sexiest intervention on the list, but it might be the most easy to overlook.  The biggest obstacle I see here is that the consequences of starvation are not immediately apparent, while maybe some of the harms, like risk for aspiration, are.  Unfortunately, I think we're usually so afraid of the potential immediate consequences of feeding that we ignore the definite long-term consequences of starvation.  We know a lack of nutrition is uniformly fatal. I think this summarizes it nicely. There's no known illness or disease that has been demonstrated to benefit from starvation.  And we know that patients in respiratory distress are burning more calories than normal. So if this goes on for even a day or two, they can create a pretty significant nutritional  deficit. We can find a bit of guidance from the societal recommendations. We can feed the stomach in most patients.  But if you're really worried about aspiration, you can go for post-pyloric feeding. And we can use prokinetic agents to further decrease aspiration risk.  If you don't want to do full strength feeds, at least for the first week, and for those without baseline malnutrition, you can at least start trophic feeding.  But most importantly, make sure they're getting enough protein, up to two grams per kilogram per day in most patients, or two and a half if you're on dialysis.  Low carbohydrate diets to limit CO2 production are probably unnecessary. But limiting the volume may make sense, if possible. And monitor the phosphate.  You can't make ATP without phosphate. Number four, inhaled pulmonary vasodilators. I'm going to include beta agonists in this discussion, which I'm sure everyone's familiar  with from COPD and asthma. But what's their role in acute lung injury? Well, this trial found no difference in ventilator-free days and a trend toward higher mortality.  Although in the subgroup with shock, they had more ventilator-free days. Similarly, this trial found no improvement in survival and was stopped early.  But there's some conflicting evidence. Meta-analysis of these three studies show that there may be a benefit in terms of ventilator-free  days, but there was, again, a trend toward increased mortality. So for acute lung injury, albuterol should probably be used selectively.  There might be a benefit in some patients, but might also be associated with trends toward increased mortality.  But if we start to look at patients with heart failure, we might see some benefit. It decreases pulmonary vascular resistance and improves pulmonary vascular function  in outpatients with diastolic heart failure during exercise. This systematic review of 24 studies with 434 patients concluded that beta agonists  may be helpful to improve pulmonary function, hemodynamics, and improve pulmonary edema. And this makes sense, right? We give IV beta agonists all the time for this.  Our main inhaled pulmonary vasodilators are prostacyclin and nitric oxide. They work through a related mechanism, but the end result is vascular smooth muscle relaxation.  We have a couple of studies showing that both agents improve alveolar gas exchange in ARDS at about the same rate, although there are limited data about long-term outcomes, which  is hard to study because these both tend to end up in the rescue therapy pathway. But it does appear that they're probably equivalent and making your blood gas better.  Inhaled milrinone may be another option, although, again, data are limited. In this series, it helped lower PA pressures in extubated patients with RV failure.  And here, showed an additive effect with inhaled prostacyclin for lowering pulmonary vascular resistance in post-cardiac surgical patients.  There have been several studies showing feasibility of using inhaled nitroglycerin, which essentially functions just like nitric oxide.  They're summarized very nicely at MCRIT, and they give some recommendations of how to administer it.  Basically, just continuously nebulize the diluted form that most of us have easy access to. If you're not familiar with these agents, it's probably worthwhile to ask for help.  There are a few things to be aware of. First of all, they're not really a treatment themselves. They're more of a bridge therapy.  They may exacerbate pulmonary edema if the resistance is further downstream, like with LV dysfunction. But they may be particularly good if patients are developing RV dysfunction.  And there are some rare side effects like antiplatelet effect or methemoglobinemia with INO, and epoprostanol tends to clog the respiratory filters pretty quickly.  Okay, number three, provide good assisted ventilation. I'd say that almost all the benefit from bag valve mask ventilation is from increasing the mean airway pressure.  But increasing inspiratory pressure by squeezing the bag harder is not what we really want to do. It causes more lung injury and gastric insufflation.  Adding a peep valve and maintaining a good mask seal allows us to increase the airway pressure more safely.  It also creates a one-way valve and prevents them from entraining room air. It also makes it easier to feel a loss of resistance when the patient takes a spontaneous  breath, and you can time their breaths more easily. Some bags have a built-in pressure gauge that helps you monitor the pressure you're giving.  And again, there's no reason to do this flat on their back. You can get a good mask seal from the front, especially if someone else is helping you, but they forgot their peep valve.  How do you get your patient to cooperate with you when they feel like they're drowning? Historically, we've considered it a bad idea to sedate someone with difficulty breathing.  But you can also think of this like procedural sedation, and the procedure is breathing, maybe with non-invasive ventilation.  I've had plenty of patients come in with acute crashing pulmonary edema, and the last thing they want is to strap something to their face.  But after some positive pressure, they're feeling much better and tolerate a lot more therapy and maybe now don't need to be intubated. I mean, look how happy this guy is.  Or if this is not going to turn around quickly, you can still use this as a method for pre-oxygenation. This was described by one of my mentors, Scott Weingart, several years ago.  This is intended for short-term treatment while someone is watching them. Let's say you're bagging the patient with a machine.  If you're going to leave the bedside, you should think very carefully about the risk and benefit here.  Okay, and the number one way to keep your patient off the ventilator is to change their altitude. What am I talking about here?  No, I'm not talking about partial pressure of oxygen or high-altitude pulmonary diseases. I'm talking about moving the patient to a higher level of care, and in most hospitals,  that means a different floor.  Identify problems earlier and be more aggressive with some of these ideas before they're looking down the barrel of a laryngoscope.  I have to include one of my all-time favorite quotes in medicine, an ounce of prevention is worth a pound of cure. Small investments early may save you a lot of work down the line.  So there you have it. There's the list of the top 10 ways to stay off the ventilator, not including non-invasive ventilation or high-flow nasal cannula, in under 20 minutes.  So choose your path, and hopefully this has given you a few extra ways to avoid a respiratory demise.  All right guys, it's a pleasure to be here. This is Brian Fuller. I'm the moderator of this session,  moderator of the Q&A portion here for about the next 10 minutes. Those were three really great  talks, and so I've got some questions, and I've also got some questions from the audience that  has chimed in. The first one I'm gonna put forth for Skylar, and one from the audience said,  should high flow nasal oxygen only be used in a setting of frequent monitoring? And that's getting to the point of to allow for sort of clinical judgment, whether I guess to  intubate or not. And the caveat sort of inserted with this question was, during portions of this  pandemic, high flow nasal oxygen was used more frequently, potentially with less than ideal  monitoring. And with that, what are your thoughts on using any of these therapies, whether it's high  flow or non-invasive, outside of the ICU where respiratory therapists might not be as readily  available? I think that's a great question. That's something that we struggled with too at our own  institution and how to deal with this. Prior to the pandemic, most patients on non-invasive and  high flow nasal cannula were in the intensive care unit. We did have some protocols in place  where patients on high flow nasal oxygen could be outside the ICU, but that was with some pretty  strict criteria. One of those was the FIO2 requirement had to be less than 50% and the flow  requirement had to be less than 50. I think the danger in having patients with high flow nasal  oxygen outside of the ICU or outside of the care, close care of a respiratory therapist is just not  everyone appreciates the amount of support that high flow nasal oxygen is delivering. It doesn't  look like a very impressive device, but somebody on a lot of flow and high FIO2 is really getting a  lot of support. Even if their saturation is 92%, if they're on 60 liters of flow and 80% FIO2,  that's a sick patient with very sick lungs. For us, most of the time, we try to manage them in  the intensive care unit. During the pandemic, we did make some exceptions. Those with DNR and DNI  code statuses, we would allow to stay out of the ICU on high flow nasal cannula in some instances.  Those with the requirement of 50% and 50 liters that requiring less than that, we did allow outside an ICU level of care. I do think that the ROCS index has potential value  in a non-monitored setting, in a non-ICU setting. It's something that could be used and calculated at the bedside to make sure that they're staying above that level that predicts  success below that greater than 4.88 ROCS index score. I think that that could have some utility  in keeping patients outside the ICU. Maybe if they're rounded on every two hours by a respiratory therapist, they could calculate that. If they're getting into a danger zone,  they could potentially move to the ICU or at least have an intensivist lay eyes on them.  Yeah, that's great. Next question, I'm going to direct. This is a question from me to Keith Lamb,  which was a great talk. If there's anything I've learned from a group of people, just as much as nurses, it's my RTs over the years. I would like to know your opinion on  what do you see clinically at the bedside to be the biggest mistake when instituting  non-invasive ventilation or mistakes, if it's plural? Mistakes initiating non-invasive ventilation  at the bedside, one of the more common serious mistakes is to select the wrong patient.  That could be a patient that has a, that is, that neuro status is inappropriate, or it could be a patient that clearly needs more aggressive intervention.  But one of the more subdued mistakes, I think, is to just slap it on the patient and walk out  of the room and expect them to get with the program. You really need to spend some quality time with the patient. I like to hold the interface on their face with them for a few  minutes, sort of get them acclimated to it, and then make changes to the machine. Some of those  changes are real subtle, like ramp or termination sensitivity, things like that, that really  customize the support to the patient. And it's, you know, today, in today's environment where  we're so busy and we're so, you know, RTs, nurses and physicians are sort of, you know, hard to find, you know, enough of them.  You know, we just don't spend enough time acclimating the patient. And so, and, you know,  as we talked about already, if it could mean the difference between intubating a patient or not  intubating them, because if you, if they immediately fail or are non-compliant, they were oftentimes  rushed to go ahead and intubate those patients, and where we could have just spent some quality  time and prevented that. Yeah, no, that's great. I totally, I agree wholeheartedly with what you said. A question for Kit, with respect to positioning. And so, we've seen much more,  and there's some good things, I think, that have happened in the COVID era. The fact that people  care now much more about pulmonary mechanics, I think, is a great thing. I think the increased  use of prone positioning in intubated and non-intubated patients has been a good thing. So, my question for you is, do you think that prone positioning or focusing more on  positioning will be more common in the post-COVID era, at least maybe in your practice pattern? And  then a question from the audience about guidelines preventing skin breakdown in patients that are  proned. So, I think we're already seeing the change, at least at my institution. Proning was  occurring prior to the pandemic, but really just in the most severe patients, and now we're using  it a lot earlier and more liberally. And I feel like with a lot of success, including even some  patients that are non-COVID that I've seen recently, because people, I think, are more comfortable with  it now. It's not this scary thing, when you flip them over, all the tubes are going to fall out.  They've seen it done several times, figured out the system, how many people it takes, who needs  to stand where, what things to watch out for. So, I definitely think we're going to see it a lot.  As you know, it makes the blood gas look better, and that reassures everybody. Then, of course,  you have to pay the piper when you flip them back over a lot of times, but I think we're going to  hopefully see a lot of data to support this, as well, moving forward. In terms of the second  question with the positioning itself and avoiding pressure ulcers and that kind of thing, I think  each institution and each group has developed their own ways, and we all are learning by  making some mistakes sometimes. We see a lot of patients transferred in from other institutions after proning for some amount of time that do have a lot of those ulcers.  We've gotten pretty good at avoiding them, I think, just by patting the right areas, recognizing what areas are at risk. We're typically doing the 16 hours prone and eight hours  supine. I have some experience with institutions that have left them prone for four days in a row,  largely just out of not understanding as much the way people have adapted to doing this.  I think as our knowledge increases, it's going to help a lot of our patients, not just the ones that have COVID. Yeah, I agree. I think it is one of the good  things that we've seen come out of this. Question for Skylar, and I think I know the answer here.  This is from the crowd. Do you use high flow nasal cannula or high flow nasal oxygen  to provide apneic oxygenation when your patients require intubation? If the answer is simply yes,  can you maybe give us a scenario where you set it up? Maybe if it's already pre-existing,  or do you specifically go to it if it's not on there? I know I'm going to intubate this guy.  Yeah, that's a great question. I use it selectively, I guess would be my general answer. What I mean by that is if somebody's already on high flow nasal cannula, I generally  keep it on. I maximize the settings. I put the flow at 60 liters or whatever the maximum is on  my device. I turn the FiO2 up to 100%, and I leave it on the entire time, during laryngoscopy,  during the induction, during the paralysis, until the tube is confirmed and secured. I'll leave it in place. I don't necessarily use it on every intubation. If someone was severely  hypoxemic, I may consider using non-invasive for pre-oxygenation because I think the positive  pressure delivered by non-invasive is more potent and is probably better at that recruitment and recruiting FRC and pre-oxygenating a little bit more than high flow nasal oxygen is.  If somebody's not severely hypoxemic, if it's purely for airway control, I think using a non-rebreather mask or a simple nasal cannula maximized is also a good thing to use for  pre-oxygenation and apneic oxygenation. So I use it selectively. If it's in place, I maximize it  and keep it on. Yeah, that's great. So we had, let's see, 20 seconds. Real quick question to  Keith. Are there any protocols for progressive step-down in gradual therapy for non-invasive patients who are very weak after prolonged intubation? Or maybe your approach to sort of  ratcheting down non-invasive in those weak post-extubation patients?  Yeah, so I think that we typically will approach that in the same way that we approach discontinuation of mechanical support in anybody, really. I don't know that there's  any utility in real incremental decrease in support. We may switch back and forth between non-invasive ventilation and high-flow nasal cannula. That's sort of become common over the  last few months. And then kind of, you know, it sort of depends on what type of respiratory  failure they have and what the etiology of it is. Great. All right, guys. Well, we're over our  10-minute Q&A session. I want to thank everyone who tuned in for watching this. I think it was  really educational. I want to really thank the three speakers who I think the presentations were  great. And I really appreciate their clinical expertise translated into this talk. So thanks, everybody. Thank you. Thank you.

Video Summary

In this video, three speakers discuss strategies for respiratory support beyond traditional mechanical ventilation. The first speaker, Dr. Skyler Lentz, focuses on optimizing high-flow nasal oxygen for patients with acute hypoxemic respiratory failure. He describes the device and its benefits, including improved oxygenation, reduced work of breathing, and positive pressure generation. He also discusses the evidence supporting its use and its role in pre-oxygenation during intubation.<br /><br />The second speaker, Keith Lamb, discusses optimizing non-invasive ventilation in patients with respiratory failure. He explains the definition of non-invasive ventilation and its indications and contraindications. He also describes various devices and approaches for non-invasive ventilation, including positive expiratory pressure devices and oscillatory devices. He emphasizes the importance of patient compliance and careful monitoring during non-invasive ventilation.<br /><br />The third speaker, Kit Tainter, discusses alternative strategies for respiratory support. He presents a top 10 list of methods to prevent intubation, including diuresis, optimal patient positioning, lung expansion techniques, secretion clearance methods, airway management techniques, nutrition support, inhaled pulmonary vasodilators, and assisted ventilation techniques. He highlights the importance of considering these strategies early to prevent intubation and improve patient outcomes.<br /><br />During the Q&A session, the speakers address questions about monitoring high-flow nasal oxygen outside of the intensive care unit, common mistakes during non-invasive ventilation initiation, the use of high-flow nasal oxygen for apneic oxygenation during intubation, and step-down protocols for patients transitioning from intubation to non-invasive respiratory support.<br /><br />Overall, the speakers provide valuable insights into various strategies for respiratory support beyond traditional mechanical ventilation, highlighting the need for individualized patient assessment and monitoring to optimize patient outcomes.

Asset Subtitle

Pulmonary, Procedures, 2021

Asset Caption

The Society of Critical Care Medicine's Critical Care Congress features internationally renowned faculty and content sessions highlighting the most up-to-date, evidence-based developments in critical care medicine. This is a presentation from the 2021 Critical Care Congress held virtually from January 31-February 12, 2021.

Learning Objectives

Describe optimization strategies for the support of the hypoxic patient
Differentiate therapeutic options for noninvasive support of the patient with hypoxia and respiratory failure progressing to possible intubation
Appraise data supporting oxygenation and supportive strategies for the peri-intubation patient

Optimizing High-Flow Oxygen
Skyler Lentz

Optimizing Noninvasive Ventilation
Keith D. Lamb

Alternative Strategies: Witchcraft and Wizardry
Christopher R. Tainter

Meta Tag

Content Type Presentation

Knowledge Area Pulmonary

Knowledge Area Procedures

Knowledge Level Intermediate

Knowledge Level Advanced

Membership Level Select

Tag Oxygenation

Tag Airway Management

Tag Ventilation

Year 2021

Keywords

respiratory support

mechanical ventilation

high-flow nasal oxygen

acute hypoxemic respiratory failure

non-invasive ventilation

positive expiratory pressure devices

oscillatory devices

patient compliance

careful monitoring

alternative strategies

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