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Kali talks about the history of ventilators and sedation with Dr. Terry Clemmer, one of the first pioneers in the founding of critical care.
Episode Transcription
Kali Dayton
Hello. Today we’re going to be talking about the history of ventilators and sedation. To understand where we are as a critical care world. And where we need to go, we must first understand where we came from. With us today is the famous Dr. Terry Clemmer, who I consider to be an ICU God. He was one of the first pioneers in the founding of critical care. And he’s here to share with us what he has seen during the past 50 years of evolution, in ventilators and sedation. Dr. Clemmer, thank you so much for joining us. Can you give us a little overview of your career timeline?
Dr. Terry Clemmer
Sure. I graduated from medical school in 1967, and did my residency in internal medicine at Tripoli Army Medical Center, and I was in the military at the time, that was during Vietnam, and just about all of us were in the military, the draft was still on. And so if you hadn’t had prior service, you got drafted usually. And that’s where I first started taking care of sick patients was as a senior medical resident, I then had the opportunity to create a new program in the military and Critical Care Medicine and that we created a new teaching program.
It happens that the general that was in charge of professional services, was one of my mentors when I was an intern, and I couldn’t decide really what I wanted to do. And so he suggested that maybe we should start Critical Care Medicine in the military. So we outlined a program and I became the first critical care medicine physician in the military. And critical care was in its infancy, there weren’t many programs around the country, there was no society yet.
There were two programs that put on symposium each year. One was in Pittsburgh, under Peter Stafford, and the other one was in Los Angeles under Harry Mac’s wild. And every other year, they would switch and have a symposium at one of those institutions. But other than that, there wasn’t a lot. I trained in San Francisco with the army hospital there. The reason we chose that is the University of San Francisco, University of California, San Francisco had a program so I could kind of take some time and go over there where we had some people who kind of knew what they were doing. But critical care is in its infancy, there was no journal yet. There was no formal programs, boards didn’t happen for about another 18 years before we had boards and critical care.
So I kind of grew up with critical care. And a lot of things changed the course is we’re going to talk about ventilators. And mainly patients with severe respiratory failure, didn’t get on ventilators, they usually just died, the people that we ventilate up until that point were people with mainly muscular skeletal problems, like Polio, and post op ventilation, of course, in the post op period, but these people had fairly normal lungs then have severe respiratory failure. And those were the days that we started ventilating, respiratory failure patients.
The ventilators we had were primary pressures or ventilators and Forsberg and Jack Bennett are the ones that had two of the most popular pressure, ventilators, volume ventilators were just starting to come out. And one of the most popular one was to our to do post op patients who is called postop ventilator. It was designed by Emerson and Jack Emerson and centrist in those days meetings and things for us bird and John Bennett and Jack Emerson would all get together at lunch and tell each other what they were doing and planning. It was it was so different, as Dr. Byrd told me, he says, you know, we shared things and we stole each other’s ideas, embellished it and now he says you can’t even talk to somebody else. Everything’s got to be confidential near other contracts, that those are the days of transparency.
The Emerson ventilator was very interesting. It was a really a green metal box that stood about four foot high and about three feet wide and two feet long. And when you open up the side panel on it, when you looked in, you think you’re looking into your kitchen sink. There were literally plugging things in there. Then there was a motor and a piston that went back and forth and a cylinder and that was the pump and it had a two phase motor uronic and you can adjust the two phases at different speed. So one phase would be an inspiratory phase when the piston would go into this cylinder and push the air out. And the other one is when it would withdraw and open the valves and fill a cylinder with air again. And by adjusting the speed on those two phases of the motor, you can determine what rate you’re going to have. So you can adjust rate and you can do it by inspiratory and expiratory times. The other thing that we can see under there was a hot plate that you could control the temperature on. And on top of the hot plate, there was a pressure cooker, like my mother had in my kitchen when I was a kid. And this pressure cooker had a couple of holes in the top with where they could attach tubes. And that was your humidifier for the ventilator. And the humidity was controlled by the temperature on the hot plate, the higher the temperature, the more humidity you got. And it was controlled, it wouldn’t get too hot. So it wouldn’t burn the lungs or anything. But it was a very simple device. And that was really all there was to it. And if you had a pipe wrench and a little electrical skill, you could fix any of it.
Kali Dayton
So there’s no way to change the pressure, the volume,
Dr. Terry Clemmer
the volume on the piston would go in and out dependent upon how you set a little lever, which knot you put it in with make it a bigger or smaller tidal volume.
Kali Dayton
But there were no sensors, no feedback from the patient,
Dr. Terry Clemmer
no sensors,no feedback,
Kali Dayton
how comfortable without going to patient?
Dr. Terry Clemmer
Well, and that’s one of the things we learned in those days is in a post op patient, I remember they had primarily normal lungs. So if you hyperventilated them just a little bit, give them a little bigger breath or a little higher rate, then you could take them over and they would relax and just let it breathe.
That once you tried to use it though, patients with disease lungs like ARDS, their lungs are in very non compliant. And they’re not satisfied with that kind of ventilation. So they would fight the ventilator. And that was a huge problem. And basically, the pressure ventilators were had some feedback because the pressure ventilator was triggered when the patients sucked in. And that pressure valve would then open up. So the pressure ventilators were easily to coordinate on a patient.
Kali Dayton
Did they still receive sedation?
Dr. Terry Clemmer
Not not, initially, when, when I was a resident for sure using ventilators. We didn’t have ICUs yet. And so my teaching hospital didn’t have an ICU. So we would just bring the ventilator into whatever room they were in and hook them up, which means you also didn’t have skilled nurses or anybody taking care of them. And once again, we did ventilate a lot of really serious lung disease. It was mainly respiratory failure from from polio and things like that quadriplegics some trauma patients.
So that’s when we started out. Then one day, we discovered that on the Emerson ventilator, as you turned up the tidal volume to try to control the patient, that the oxygenation would get better. And the co2 in the arterial blood would go up, didn’t have OXImeters in those days, so he had to actually draw bloods every time he wanted to see what was happening. So that login, so he started using higher and higher tidal volumes, about that same time, and I think it was 68 or 69. Tom Petty from Denver, and Dr. Nash BA, published the landmark paper and coined the term acute respiratory distress syndrome, er DS in respiratory distress syndrome was already known. And so the pathophysiology was somewhat similar.
And so when they started seeing this in adults, they termed it ARDS. And he also described a mechanism of trying to oxygenate them better by using positive expiratory. Pressure, or peep. And so we started using peep on some patients, none of our ventilators had peep. And so what we did is we took the exhalation port and put a hose on it and stuck it underwater. And the depth underwater with determine how much positive expiratory pressure you’d have.
And we did that for many years, actually, before we were able to actually build that into the ventilator. As we tried to dial up the tidal volumes, the increase our oxygenation and started using now to reverse hypoxic respiratory failure and use it on those kinds of patients. The patients hated it. They would find it enough to then the patients tolerated being ventilated. being awakened, and with the program, but now we are forced to start controlling them by other means.
And that means was heavy sedation and or paralysis. And so we would heavily sedate the patient paralyze them in order to coordinate them with the ventilators. Even as the ventilators became more sophisticated. And in the early 70s, we started seeing new ventilators. The two primary ones were the Ohio 560, the Puritan Bennett, MA1. And those the we now had enough sophistication with microprocessors and things that we could actually start to coordinate them with the page patients needs, it didn’t solve our problem. So and, and we got used to taking care of patients heavily sedated and felt that that was good that they would like be asleep during this period of their life and, and not having any memory of what was going on.
Kali Dayton
And that’s the way it was interpreted, right. That it was sleep.
Dr. Terry Clemmer
Yeah. And the nurses liked it too, because it was easier to take care of the patients sometimes. And so we continue to use heavy sedation and paralysis in order to coordinate the patient with a ventilator, the machines became more and more sophisticated. But we continue to use the big tidal volumes, not realizing how harmful that was to the patients.
And I think that’s an important thing in doing research is you have to remember here, if you’re asking the right question or not, the question we ask is, can we improve the oxygen in the blood? The question that should have been asked is this beneficial to the patient? Because it took us 20 years before we discovered the fact not only was it not beneficial, but it was harmful to patients.
So and that’s an interesting story, how we came about it is doing extracorporeal oxygenation, Dr. Ganton, only in Italy, described using very small or no tidal volumes, because he could oxygenate the patient with extra corporeal support. And the mortality rate, which on severe ARDS was over 90%, he reported a mortality rate of only about 60%. So that was a big breakthrough. But in addition to doing extra copper support, the other thing he did is use very small title lines, or none, and modest peeps.
Let me tell you, about people who have metal, there is a time when we’re so enthralled with peep, we were using 50 centimeters of water peep. That was popularized by Model and down in Texas, and then put our tidal volumes on top of that, and our pressures are going up into the 80s and 90s. They recall, it was called “Super peek”. And in fact, there’s still papers out there on super people and how it actually so much better patient survived that.
Kali Dayton
And patients survived that?
Dr. Terry Clemmer
Some did. And then there was another landmark papers. And then it kind of got us away from that is Peter Souter, who is in San Francisco that same time I was doing my critical care fellowship, published landmark paper, Pete was good at he got a certain level, and then a depressed cardiac output. And he worked out all the all the mathematics of that and experimental trials on it.
And it turns out that when you hit your best compliance when you’re you’ve opened it up the lungs with peep, but once it’s open, if you go higher than that, then you start depressing cardiac output, so you should stop at best compliance, and he developed the concept of best peep. And so we backed away from these super peep, because it was obvious that they are depressing cardiac output and stuff and came down to a more modest peeps. So we work with that.
Meanwhile, of course, he was several years later with getting known his work that these the no ventilation are very small ventilation, those patients did better than a motto out of Brazil, came back with some observational studies in patients showing that the patient’s outcomes were better with smaller tidal volumes. So we begin doing smaller tidal volumes and in the air DS network, which we were a part of picked up on that concept and the definitive trial demonstrated that smaller tidal volumes in the range of six mL per kilo actually had much better outcomes than using the what was then the traditional tidal volumes of 10 up to 15 mL per kilo.
And so we stopped doing that, but we didn’t give up the one the sedation and, and mobility and things. And so we continue to sedate the patients heavily. And until one day when one of my nurses actually followed a patient longitudinally, out of the ICU into rehab, actually to her home, and discovered what terrible harm we had done to her. And that she was deconditioned, to the point that she couldn’t even call the nurse on the nursing button, and the pain of all the rehabilitation and things and, and she began to realize, and then the, the psychological problems with flashbacks, and PTSD and all of those things that occurred during sedation.
Kali Dayton
that wasn’t sleep.
Dr. Terry Clemmer
Yeah. And then she realized that the sedation and the mobility that we were causing, was very harmful to patients. And, of course, about that time was probably what, late 90s that Margaret Heritage at a Toronto published her results of survivors with ARDS and all the psychological and brain problems that they were having. And then that became fairly well known.
Unfortunately, it’s been difficult to give up the sedation and actually start mobilizing patients, we forgot that that can be done. I mean, we used to do it in the early days, we got to the point where we felt it was dangerous, to not have a patient sedated that talked ourselves into the idea that if they’re not sedated, they’re going to pull out all their tubes and, and have all these terrible experiences in the ICU, that’s gonna affect them for the rest of their lives.
And, and that’s where we continue to do that until a few were brave enough Polly Bailey, one of the first ones doing that, and taking the sedation away, and actually getting patients on ventilators up and walking them around the unit.
To discover that one day, we discovered, you’re just looking around and said, Hey, we used to send all of our ARDS patients to rehab when they left the hospital because they were so deconditioned. And they needed the the mental support and stuff that they needed to have. And then all of a sudden, she says, you know, we’re not doing that anymore, our patients aren’t going to rehab, they’re going home.
And we actually studied that and found that if a patient can be walking 200 feet before they leave the ICU, they all go home, they don’t go to rehab. And so we started reducing our sedation and trying to eliminate it and became very vigorous at mobilizing the patients. It’s not an easy task. I mean, it takes coordination between physical therapy and nursing and respiratory therapy and to really make that happen.
But the nurses started to change their attitudes. And say, “You know, I can take care of patient awake and alert, and they’re not pulling out all their tubes, and they’re not dying. And in fact, sometimes directly cooperating with us that communicating with this, they can tell us what they want and what they need.” We’ve even had some patients that are there with their laptops on a ventilator on high , fi02 and high peeps, running their businesses on their laptop, in their hospital bed. And so they can be functional. It’s just, it’s just fun to watch it happen. And it’s fun to engage the families, the families also much more interested in coming in and visiting with them. And they have a much bigger role in helping take care of their loved one.
Kali Dayton
So you’ve watch this evolution throughout the many decades, what what kept your mind open? So when Polly came to you and said, “I actually want to try something that no one has ever talked about thought of I don’t know. There’s no research on it. I want to try this thing.” What swayed you?
Dr. Terry Clemmer
I have a history that goes way back. When I was still in my fellowship and critical care. There was a night in which we had a sick patient and I was in the ICU in the middle of the night. And one of my nurses, her name was Kay Milliken. She only worked nights she was actually not in the military, but was a civilian nurse, but took a lion’s share of the night shifts. And came was a very bright young lady and, and I was sitting there and and I was trying to teach her about pulmonary compliance. And she was very patient about me trying to explain what it was and, and all that and as we’re sitting there and remember all we had was these ventilators those days, she looked up at me and said just a minute. And she got up and went over and reconnected a ventilator. They didn’t have alarms on them in those days.
And I looked at Ken, I said, Kay, how did you know he was disconnected? And her answer to me was, couldn’t you hear it, she was so attuned to the environment, that a disconnect like that the ventilator just sounds a little bit different. And she immediately picked up on it. And I suddenly realized how much knowledge a nurse has, that I did not have.
And then a few nights later, we were short on nurses, and we had a fairly full unit. And so another physician myself decided we were going to be we would work as nurses for the night shift to help the night shift out. And that was such a learning experience, on how I am not a nurse and cannot be a nurse, they have certain skill levels, and way of organizing things and getting things done, that it was a disaster.
The one true nurse that was in the unit that night, saved our lives, I mean, life, and make sure all the medications are delivered on time, and all those kinds of things. And I come to realize that, that nurses have a skill level that physicians do not have. And they have to be symbiotic. They have to work together. And so I had a much higher respect for nurses and nurses opinions. And I quickly learned, you know, if you really want to know about the nurse, you go to a nursing report, and they’re a nursing report, you find out all kinds of things that you never know, by listening to the house staff report on a patient. And so we started to use in joint rounds.
And so I developed a system even on the military at that time, which was almost unheard of, of having joint rounds with the nurses and therapists and things. And I’ve done that then the whole rest of my life. And we instituted that back in what 1972. So that’s almost 50 years ago.
Kali Dayton
Now, that was not the culture. Yeah.
Dr. Terry Clemmer
So. So I learned to have a great respect for nurses. So although I didn’t always agree with them, I did learn to listen to them. And so when Polly came and said, “you know, we’d like to try this”, you know, I was, I was somewhat skeptical about it, it’d be an effective and stuff, but you know, why not. And Polly is a good nurse, and she protects her patients. And I know the patients will be safe butter. And so, you know, I let her let her try it and quickly discovered what a what a wonderful idea was to actually have patients communicated and walking in and helping in their care.
Kali Dayton
So where do you see as heading in the future, in regards to sedation and mobility,
Dr. Terry Clemmer
I think I think it’ll eventually catch on stronger and stronger. And eventually, that will be our mode of how we take care of patients in the future. It’s hard, though, it’s hard to change culture. And a good example is that as we were never able to fully implement that, in the Shock Trauma ICU, the Shock Trauma ICU had some very, very good and very seasoned nurses but very opinionated nurses, and to get them to change the way they practice was just not going to happen.
And that’s when we split off the respiratory ICU, where we couldn’t get the older nurses to come down because there were more chronic event type patients, and they wanted acute patients, you know that they can do something or get them out of the chronic chronicity the unit wasn’t attracted to them. So we ended up hiring a lot of new grads that didn’t know any better and started a new culture. And then you have one of those was brandy. And, you know, Brandy is so vehement. She really believes if you’re not up and walking around, you’re doing harm to your patient. And it’s a disservice and something that we will not tolerate. So it’s it’s an it’s a new culture that’s coming around.
Kali Dayton
Well, it’s exciting to be a part of.
Dr. Terry Clemmer
Well, but the bad thing, though, what you realize is how many patients have I harmed over all those years? I mean, we’re talking about several decades of evolution here, and ARDS with a 90% mortality rate, and now it’s down in the 20s and 30%. How many patients do we kill with that therapy? How many patients are still not functional years after their ARDS? And what are we done to their brains? And Margaret Heritage has some data out, you know, now 10 years, showing that these patients that develop the disease and the prime of their life in their 40s 10 years later cannot return to work.
Kali Dayton
A third of ICU survivors are not back to their jobs 16 months after discharge. And that’s even now here in 2018. That was 2017. That data was collected. Yeah. I, we had a travel nurse come from another part of the states. And he was used to using Versed drips, everyone was sedated. Everyone got trach’d and peg’d if they were on the ventilator. And he came here, and we told them what we did.
Everyone was awake that everyone almost everyone was walking, no one gets trach’d or peg’d. And he was excited, but very incredulous. And after probably a month or two, he came to me almost in tears, because he was watching a patient that had come from another hospital that had been sedated for 10 days and wasn’t succeeding. So they brought them here. And then we took off sedation, and they were severely delirious and severely deconditioned. And he’d never seen that before, because by the time they turn off the sedation elsewhere, they’re in LTACH.
So he didn’t witness the process of clearing out delirium and what that looks like. And so he was really distraught and was asking a lot of the same questions. You’re asking how many patients did I unknowingly harm? And I think that can be very haunting. And I think it’s hard to consider that we cause harm to patients, because I think everyone gets into the profession with noble aspirations desires to do well, I think, especially nurses, this is handed down, generation to generation. And so when I’ve mentioned to nurses, that we don’t sedate her patients, they get a little defensive. It’s hard to consider something so different, so new. And then it’s even harder to consider that what we’re currently doing is going against our ethical obligation of doing no harm and helping patients get bette.
Dr. Terry Clemmer
But they actually believe that if you don’t sedate them, you’re going to do harm, right? That the patient is going to be harmed with no sedation.
Kali Dayton
And reasonably so. When you have a patient that’s been sedated and you take off sedation. They have ICU delirium, so they’re confused. They’ve been having hallucinations and tears this whole time they were sedated. And now you’re taking off sedation, allowing them to move their extremities. And they don’t understand what’s in their throat. They’re uncomfortable, the tie down to the bed, nothing makes sense. So what the nurses are seeing as when you take off sedation, they’re go crazy. They’re climbing on the ceiling trying to pull the tube out, because they don’t know that the sedation has caused that.
What we see here is if you just don’t sedate patients, and they wake up after intubation, and you just re explained to them everything they understood before that you’re in the ICU, you had this breathing to the families, they’re they’re reoriented, they never, they almost never get confused. I mean, there are other confounding factors like delirium, like sepsis, that can cause delirium, but most of our patients really are oriented, they’re able to get real sleep, they keep a clear mind. They’re compliant, they have autonomy, they can express what they need, they can make decisions about their care. So that’s what our nurses see.
So understandably, if you’ve never seen that, and you only see patients that have had sedation and are confused from it, there is that legitimate fear that they will not tolerate, the tube won’t keep it in. But I’m excited about the prospect of everyone understanding that if we don’t make people crazy, they don’t do crazy things.
Dr. Terry Clemmer
They don’t. And actually, mobility especially, is very therapeutic. I mean, if your patient starts to have delirium, we’ve learned to actually walk them around the unit and see the delirium clear. It’s certainly beneficial to sleep if you walk. And I’ve had that experience with my great grandchildren, that if they’re having trouble going to bed at night, if I’ll walk around the block with when we come home, they’ll go to bed. And so it really is conducive for sleep.
And I think you have a much better sleep. After we’re talking about vigorous exercise, we’re talking about just an activity of some kind. So it’s very therapeutic. It’s also interesting in and I’ve experienced this several times of, of a patient, just getting them up and dangling them at the bedside, where all they can do before that is maybe open their eyes to a command, rather loud command. And they’ll open their eyes but even in that state, if that’s all they’ll do, they won’t obey and the other commands is In the bedside, their eyes come open, and they suddenly become in contact with their environment. And, and that is, it’s just thrilling to watch.
Kali Dayton
You know, I’ve seen that the light comes on. And I’ve had, you know, nurses ask, well, they they’re barely opening their eyes, why do we have to dangle them because there’s a lot of work, we can do a lot of work to, to have someone sit up that mentally can’t quite control their body. But once you see them, that light come on, they start to interact. And even if they’re not mentally there yet, even just holding their head up, is of great value as far as their long term outcomes of being able to protect their airway. It wasn’t until I was a travel nurse, and I saw what it looked like when people couldn’t hold their own head, they were they became newborns.
Again, they couldn’t, yeah, they couldn’t get their own head off the bed. And so of course, they can’t protect their airway, and they can’t breathe on their own. And because all these other problems, so it’s exciting to consider that we have more data, more research out there, validating all of this, and hopefully, the culture will continue to evolve and change. And these good nurses that have these good desires, will be empowered to make those changes.
Dr. Terry Clemmer
And we have several very good institutions around the country, places like Vanderbilt and Johns Hopkins and others that are, they’re publishing some really good papers on this now. And I think it will, but it’s still a barrier to, to make such a dramatic change, of going from keeping your patient as no totally unconscious, basically, to walking is a big paradigm shift. And the idea that a patient on a ventilator with a tube in his mouth can walk around the unit safely. We’ve never had an unplanned extubation- I can’t ever remember an extubation during an activity like that. Now, we’ve had a few extubations where, you know, there’ll be an accident, the patient will, unconsciously pull the tube or something like that. But their activity, we have enough people around them to prevent that we’ve never lost it to.
Kali Dayton
And statistically if they do accidentally self-extubate, which again, those rates here are just as if not lower than those that are sedated. If they do lose that tube, they’re much more likely to succeed and then not need to be re intubated, because they’re already so strong and able to, to breathe on their own, because they’re not deconditioned.
Dr. Terry Clemmer
And cost wise, there’s a huge cost savings, if you can prevent patients from having to go into rehab and, and do all that post hospital stuff. It’s very, very expensive. So it’s very, very cost effective in the end, not to mention just the cost of some of the drugs that we’re using to sedate patients with
Kali Dayton
oh, I hadn’t thought of that. Yeah, yeah, definitely opened up more IV access.
Dr. Terry Clemmer
It’s interesting. Another little antidote is in the days where we’re sedated patients do an extra corporeal support for whatever reason we wanted to drip or said, and we couldn’t keep it from precipitating. And we asked other people how they’re makes it and all that. And it turns out that what we didn’t realize is Versed, and Lorazepam. If it’s cold in the refrigerator, which we kept it, if you put it into a larger bottle, it will precipitate if it’s cold. Whereas if it’s warm, it won’t. So it’s just the temperature of the drug that caused that.
Kali Dayton
But that’s a lot of extra things to play with and try to figure out and in the end, probably wasn’t necessary, and it was definitely harmful.
Dr. Terry Clemmer
And probably one of the worst drugs you could use as far as delirium goes, correct. Yeah, delirium is not a laughing matter. I mean, there’s very strong data of delirium and long term outcomes and even death patients with the more delirium they have, the higher the death rate.
Kali Dayton
Yeah, that patient that came from outside hospital ended up essentially dying and delirium. He was had early onset Alzheimer’s had aspiration pneumonia from a procedure and, and develop such severe delirium that he just didn’t clear. And I think I just kept thinking about back to that moment when they decided to sedate him elsewhere. I’m sure the conversation was he has Alzheimer’s, so we better sedate him. But here the conversation would have been. He has Alzheimer’s, so he had better not him. Probably good time to end. Thank you so much, Dr. Clemmer.
Dr. Terry Clemmer
Oh, you’re welcome.
Transcribed by https://otter.ai
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