Beyond the Surgeon – Meet Your Anaesthetist & ICU Team

0:01 [music]

0:17 So, welcome. No, I think we'll be okay with this one. Lovely to be here. Thank you very much for the invitation.

0:28 Um, I suppose the first thing you'll think when you're told you need aortic or major vascular surgery is who's going to be doing my operation? But I'd put it to you that perhaps you also need to think about another question. Who's actually going to be looking after me while the surgeons doing that operation? And I'm here to tell you all about that.

0:49 I'm a consultant cardiacist at St. Bartholomew's Hospital and my name is Martin Lee. These slides are going to be quite visually impactful and I hope that's okay with you today.

1:04 The first question is who is the anist? So I'm an anist. What does that mean? I'm a medical doctor. I've trained at medical school. I've done about 10 years of post-graduation specialization. We've done fellowships in often different countries. and we lead part of the team in theater.

1:27 So what is our core role? It's to meet you, discuss your anesthetic plan, put you to sleep, keep you safe, monitor the many things we have to keep an eye on, and then it doesn't stop there. I'm also an intensivist. So when you're duly accredited, you can also look after patients in intensive care. And that's where another journey starts. We'll talk a little bit about that as well.

1:55 This is some of the major centers in the UK and it's not really about the numbers of cases that all these centers are doing. And some of you might be familiar with some of these centers. I'm working at the center at the bottom. It happens to do slightly more cases than some of the other centers. But what you can see here is that there's a mixture of elective and emergency aortic surgery.

2:21 And generally these days expertise that has to be very specialized needs to be centered around the patient with all the services that they will need all the experts and that's much easier if you have fewer centers doing larger volumes. So the more elective surgery we do potentially in the blue humanoids here the more we're prepared when we have to do emergency services.

2:52 So the best way to think about what the anesthesia team and the supportive staff around the anesthetist are doing is by looking at how we optimize everything and expertise and manage ourselves as if we're in an F1 pit. And if you look at this slide and imagine that you're the driver of this F1 car, that's how we organize ourselves around you. So there's a whole mixture of people. There are people supporting the anesthetists, anesthetic nurses, ODPS. There are people supporting the surgeon, and the surgeons at the top there in red, of course, as you'd expect.

3:27 Um, but there's a group of people there. You might not understand what they do, and I'll talk to you a little bit about them in a minute. They're perusionists. And then we have theater managers. We have people involved in monitoring and special equipment. And all of these people need to work seamlessly together. We're all on the same song sheet and we're all singing the same song. And the more we do that and the tighter that's managed, the better the outcomes.

3:57 But before we even get to the theater, there's a whole lot of work to do. So imagine that you're effectively auditioning for your place in the F1 team. You have to come and see us and a mixture of people will assess, not because we want to stop anything happening, but we want to minimize risk. So, it's all about evaluating your past medical experiences, your history, your allergies, what drugs you're on, and how well your organs are performing already before we put them under a bit of pressure.

4:27 And in this um situation, we can understand everything about making a personal plan for you. And the most important thing about that is sharing that plan with you, explaining what we're going to do and helping you to help yourself prepare for this operation so that we can make it safer together.

4:49 Understandably, this looks quite a lot. And I think the most important thing about this slide is this is what the anesthesia team and the team around us are doing in the anesthetic room or in the theater. And I'm not going to go through this line by line and explain all the things we're doing because I don't need to. I just want you to know that all these things are there for us to manage risk down. If your body does something that we can measure, we generally measure it. So within the anesthetic room environment, we'll be placing little lines under local anesthetic and then getting you gently off to sleep. Of course, we have to take over your ventilation and we'll be putting you on ventilators. All the other monitoring that's specialized will be put in when you're fully comfortable and asleep. And that includes things that monitor your spinal cord perusion, things that monitor your brain, and things that monitor your blood pressure and your kidney function. And all of these things are vital for a combined successful outcome.

5:58 Of course, we need help. So, this is where the role of the anesthetic nurse is is so crucial and there's an awful lot of complex equipment around. So we have technicians, we have echo expertise to look at the heart while we're going through the operation. And all of these things are vital. We can't do without any of them.

6:22 So I mentioned earlier perusionists. I don't know if we have any perfusionists in the audience today. No perfusionists. But they're clinical scientists. They've done a degree in clinical perusion. They're not doctors, but we work extremely closely with them. And they're vital to this. And why is that? Because when you're operating on the heart or the major blood vessels, it's not possible to operate on them while they're moving or when there's blood flowing through them. It's a little bit like trying to mend a water pipe when the main services haven't been cut off yet.

6:53 So, they're they're a very expert member of the team. And at some point when the surgeon gets to a stage in the operation where they need the tap switching off that's the point at which the perfusionist comes in and we effectively as yianists hand over some of the care to the perfusionists. They run this complicated equipment here on the left that you can see called the heart lung machine. And in the schematic in the middle you can see some elements of that. Effectively, we bypass the heart. So the heart can be made still for some types of operations and all the blood that would normally be going into the heart is diverted off to a set of pumps, oxygenators, heat exchangers and pumps that send it back into the body.

7:42 Now that sounds quite complicated, I know. And now the technology is so good that there's minimal risk doing bypass. But sometimes the type of operation that our surgeons are considering and that some of our patients need require the water to be switched off completely and not recirculated.

8:01 And that's the schematic you see on the right. That's called circulatory arrest. And we try and do that for as short a period as we can which is why it's so essential that all the members of the team are working effectively together, communicating with each other and are on top of their game. It's not really stopping the circulation. It's more like a pause and it's planned. So, it's not an emergency. We do this in a considered and planned way.

8:32 You might see also and have noticed that in the far right schematic there's a roller pump running some blood directly up to the brain. That's called antigrade cereable perusion. If we stop the water, everywhere has no flow, including the brain. Now, part of the protection is to cool the patient. We'll talk about that in a minute. But part of the mitigation of that, because we can't do that forever, is to actually run some oxygenated blood directly to the vessels that supply the brain. And that's one of the best ways to protect the brain.

9:13 So a little bit about moderate hypothermic circulatory arrest. This makes complicated difficult aortic surgery possible. Without this, it wouldn't be possible to do some of the operations. But as I've just said, it's a planned pause rather than something we just have to do.

9:34 Not surprisingly, there might be some risk with this, but we do everything we can to mitigate that risk. And that includes um problems with um potentially changes in the coagulation of the of the blood and issues with the kidney function and to some extent with the brain itself.

9:56 So while we do this, we've got an advanced system of monitoring of the brain. If there any indications that we know that the brain is under pressure then this is the way in which we can step in. So on this slide you can see two types of monitor. There are actually others but in our center we combine these two and one of them has a set of little bright lights that are looking at how much oxygen is in the blood that's in the brain. That's very important.

10:26 That's the amount of oxygen that's being supplied to the brain by the antrograde cereal perusion. The other one is an EEG. It's an electrical impulse that we might measure if we wanted to diagnose epilepsy or something like that. But in this setting, we can look at the waves and if there are any changes, then those numbers will change and then we know there's a problem. We can see both from the supply side and the function whether there's an issue with the brain. And this is not about tolerating problems. This is about stepping in before the problems become permanent.

11:05 So, how do we know that what we're doing is the best we could do? How do we even know whether it's good enough? Well, of course, there's medical research, there's innovation, and there are lots of people who want to try and make this better. We're pretty good already now and we've come a long way. So, these are just three examples of what we're doing at Bart's Heart Center in London to make things even better. And it's a continuous cycle of quality improvement.

11:31 And the one on the left shows a study that Prof. U who sadly can't be here today uh started looking at um 10 or 15 years ago. And that's at what rate should we peruse the brain with the antigra cable profusion. And it's been now reasonably well established that there's a range and that more simply isn't better. So there's a point at which pushing more blood into the brain creates more trouble than it's worth. And that's a nice bit of research that's actually translated into clinical practice.

12:06 So there's some complex equipment there in the middle. The perusion pumps have become a lot more complicated. That new technology has allowed us to run far more selective perusions. So whether we want to peruse the brain and the lower body at the same time, that's limited by the number of roller pumps that are on the perfusion machine. So we've just acquired a whole load of new quite expensive charity funded perfusion machines that now allow us to selectively um peruse different parts of the body whilst we're on circulatory arrest. And that now allows people to do staged operations or indeed just more of the antig-grade cable profusion than they were able to before.

12:49 And then finally those very expensive profusion machines came with quite a nice clinical information system which allows all the data from the whole profusion episode to go back into the system and we can use that as part of our quality improvement audit and research data set.

13:11 But of course, it's not over when the operation finishes. An ICU is not just a place where people who have very high medical needs go. It's the place where we plan to reduce all the support that we've introduced to get you through these procedures.

13:29 So, who works in an ICU? Well, someone like me. And I generally work with the nurses to do ward rounds twice a day at least. We continuously monitor the pace of change of what's going on. But we can't do it alone. We have a more junior medical team that works with us, but we also have the surgical team who are represented in the ICU. We have an awful lot of other staff too. We have physiootherapists, pharmacists, radiographers, all doing different parts of the the complex puzzle.

14:03 We'll probably be introducing support to different organ systems as we go along. Sometimes the most likely things are kidney support and sometimes the ventilator support needs to continue for a little while. If we have to support the heart, we'll do that and sometimes that can be quite complex but we've the more of it we do, the more experience we gain, the better we get at it.

14:30 And this is a list of the the hazards in ICU. This isn't a list that applies to everyone. And if you're in ICU, you don't often suffer more than one or two maximum of these complications. But these are the sort of rates at which things can happen. And this isn't really a list of things to frighten us. It's a list of things that we know sometimes need to be addressed. So instead of reacting to them, we're actively looking out for them. We're looking out for signs of stroke. We're looking out for low profusion of the kidneys. And we're starting to filter early to support the kidneys. We're trying to act before anything gets out of control. And we do that as a very extended team.

15:16 You see there, there are complications involving specialties that aren't actually in ICU. We have regular ward rounds with the microbiologists. We have regular input from the interventional radiologists. And all of these people are utterly crucial.

15:36 But of course, most patients do well in ICU. We reduce their support. They start to eat again. They start to mobilize. The physios will help their chests. and then we can move to discharging patients. But even after intensive care, it's still not over.

15:54 And we have a post ICU follow-up clinic and that's a very important place. Sometimes patients are with us for a reasonable length of time and occasionally they still have some issues going on.

16:11 Sometimes those issues are psychological. Sometimes there are needs that the family have. And in this multid-disciplinary clinic, we can understand and give a time to reflect on what has happened, what's gone well, what's still outstanding. And we are all trying to get you back to your loved ones and get you back to doing what you want to do.

16:38 So, I'd like to thank the association for asking me to present today. I'm very proud of being part of the team at Barts and it's a great privilege to look after patients like you. Thank you.

16:49 [applause]

16:58 We've got a moment for a couple of questions. I'm just going to take chairman's privilege and ask my own one first. Brian, can you tell us a little bit about ICU delirium and psychosis?

17:06 Yeah. I had 10 days of very profound visual hallucinations after being on ICU and I think that kind of thing is quite common. What have we learned about it and what are we doing about it?

17:15 Okay, so uh ICU delirium is not uncommon and delirium is psycho motor agitation or it's people who just don't engage with you and it's usually a well it's not known actually what causes it but it's associated with a poorer outcome.

17:32 So we know when we see delirious patients, we've got to start looking for sepsis. We need to organize our drug chart better, take away drugs that might cause delirium, like benzodizopines. And we know that sometimes we need to step in to stop the delirium getting worse.

17:48 But the problem is we don't really know what causes it. And I think the likely theories are that there's a change in the permeability of the bloodb brain barrier. So the membrane around the the brain, the mechanism that stops the wrong chemicals going across the bloodb brain barrier into the brain is made more porous and then other things start to go into the brain.

18:09 But of course we have a lot of drugs that we use during this process and switching them off also has an effect and there's to some extent withdrawal from opiates. So that can be a problem.

18:20 Sometimes people came in having smoked an awful lot. Withdrawal of nicotine can cause delirium. People sometimes drink too much alcohol. That's a common problem actually. But if we spot that, we've got a good treatment for that. It's called dex metatomdy.

18:35 But I think one of the crucial things that we haven't addressed, which we're actually starting to address now with a new guideline, is how we sedate patients when they need to be kept asleep for a while in the ICU. There's quite a lot of evidence that if we strategize that better, we'll have less delirium later.

18:55 So, we're definitely trying to do things to improve delirium and it can be a very distressing symptom and it's quite often a problem that's discussed afterwards in the post ICU clinic, but I think we're starting to get a handle on it.

19:08 We've also just introduced a delirium ward round once a week and we've introduced some charity funded projectors with interactive images that are reassuring in a way that delirious patients can find helpful. Although that has not been evaluated in the clinical trial.

19:29 [music]