Diagnosing Aortic Dissection in the Emergency Setting

Moving on, we're going to move on to the first session of the afternoon. We're juggling the agenda slightly but one of the things that we've learned as a patient organization this year and one of the discussions we've been having with the Royal College of Emergency Medicine is that aortic dissection is often missed as a diagnosis in the emergency setting and the Royal College of Emergency medicine has been very honest and very humble and accepted that yes aortic dissection is often a missed diagnosis in emergency departments and as we heard this morning that can often be fatal for the patient concerned. So one of the arms of our work as a patient association is to improve diagnosis of aortic dissection in the emergency department and to improve the time it takes to get patients with a dissection in front of the people who can treat them which is usually for type A a surgeon. So this is a really important arm of our work. We have a campaign called Think Aorta and with the Royal College of Emergency Medicine we produced a podcast earlier in the year featuring two patients and two doctors talking about their experience of aortic dissection and a think aorta poster, which is a little educational piece that was distributed to every emergency department in the country to put up to educate clinicians about spotting aortic dissection. And I'm delighted that today we've got with us two clinicians from University Hospitals Bristol NHS Trust, Dr. Emma Redfern, who is a consultant in emergency medicine, Professor Mark Calloway, who is a consultant radiologist, and so knows all about CT scans and the importance of that in aortic dissection. Mark and Emma have been working together to improve the way the Bristol Emergency Department detects and diagnoses aortic dissections. It's a real pleasure for me to welcome them to our meeting this afternoon to talk about their work. I I think, Emma, are you up first? Emma Redfern and Mark Callaway, ladies and gentlemen. Hello. Thank you very much for having me here. It's a flying visit for Mark and I, but we really want to tell you about the work that we've been doing at UH Bristol and the reasons why we needed to do it. So, for the ED, making the diagnosis of aortic dissection is actually quite difficult. It's a relatively rare condition, so one in 10,000 ED attendances. At my unit, we see 80,000 attendances a year, so that will be a dissection possibly every other month. And what we need to do is to be able to deliver the diagnosis of that 24 hours a day from all my clinicians as quickly as we can and get the patient to surgery. I have a sad story to say. I led the safety for the ED since I was appointed a consultant in 2012, and the first very serious cases I had to deal with over 18 months were three men in their 40s who were misdiagnosed and discharged from the emergency department with a diagnosis of gastritis or gallstones. They all subsequently died in the following days. So we undertook a root cause analysis, which is what we do in all serious safety incidents, and we had a serious incident panel review at Bristol, which involved ED consultants, radiology consultants, and our cardiac surgeons to look at why this had happened. And it revealed a real knowledge gap across all those groups of people. We were relying on traditional teaching that the patient would always have a discrepancy in their pulses, so we would always be able to feel that there wasn't one present on one side. There would be a blood pressure difference, So the blood pressure would be markedly different in each arm, and that the chest X-ray would be abnormal. And that's what our clinicians were basing their decision to do a CT scan on. But there are some subtle differences in the way patients present with chest pain. We see lots and lots of patients with chest pain. We have 200 adult patients per day through my emergency department, and about 30 of them will present with chest pain or collapse or back pain. But in the story, in the history taking, the onset of symptoms with aortic dissection is often like that, very, very quick onset. This pain can be in the chest, it can be in the back, it can move. And the biggest problem for the ED team is that by the time we get to see the patient, they've often settled. And the clinicians cannot understand how you can have a life-threatening diagnosis and yet be sitting there going, actually, my symptoms have settled down now, I feel much better. But at the time, I thought I was going to die, and that's how patients describe this. Something happened so quickly, it was so catastrophic. They call an ambulance when they've never been in an ambulance in their life. They've come to ED and they've never been to ED before. And they're sitting there with no pain. Their baseline tests that we routinely do in A&E for chest pain, so their troponin, their heart trace, their chest x-ray look apparently normal and they are well. We do see patients with symptoms that don't fit. So I've had chest pain and also a weird sensation in my neck. I've heard people describe it as a shiver down my body. It went through my neck, through my back, into my legs. People have described stroke symptoms, transient stroke symptoms, so I was paralysed down one side. We as clinicians are very geared up to dealing with chest pain or stroke and we don't often see the links between the two. The D-dimer, which we do for looking for PE, so pulmonary embolus, is often raised but but it's not specific enough for us to make that call. And frozen ED, a CT of your aorta, is the only way we can make your diagnosis. And you can see there, just in the middle of that aorta, the dissection. As a clinician, if you're lucky, your patient will have a pulse deficit or a systolic blood pressure difference. They may have had chest pain or back pain or abdominal pain plus signs of a stroke transiently. Hearing an aortic murmur, so a valve murmur across the heart in A&E is very difficult. For those of you who've been there, it's noisy and chaotic and hearing those subtle murmur changes are hard. Once you've developed shock and hypotension, the diagnosis becomes much more straightforward because you are then very, very unwell. There are ways that people have looked at risk stratifying patients with aortic dissection. D-dimer is a simple blood test and it is often raised in dissection, but it's also raised infection, it's also raised in pulmonary embolus, so it doesn't give you the diagnosis. The chest x-ray, the myths about chest x-ray which Mark will talk about, is often normal initially, so these patients that present to us are often dissecting a normal caliber aorta, and these, the changes that are seen on x-ray take some hours to develop. There was a relatively good tool published in circulation in 2011 about how emergency departments might risk stratified patients. But at the end of the day it pointed towards if you don't have a better diagnosis you need to end up scanning the patient. So these are the things that we do know about dissection, over a third of cases are missed on the initial presentation. The chest pain is very, very sudden and very severe, maximal at the time of onset. It doesn't build up in a crescendo, it is there with 10 out of 10 immediately. It can move, it can radiate, it can go into the back, abdomen or groin. I've had two patients with no chest pain who've only presented with back and groin pain. Syncope, loss of consciousness, is something that we see. I think I've seen it at Bristol in more than 5% of the patients. So after we had our serious incident panel review, we realised that we needed to teach out the historical inaccuracies to our junior doctors. just in the ED but in the medical teams and in the cardiology teams. So we commenced a rolling teaching programme for every single doctor that rotates through the emergency department which has happened since 2012. I personally taught every single doctor that's worked for us. We have 30 change over every year and a few in between times. We teach them all the things that I've just shown you. We tell them about the cases that we missed. We tell them about the missed diagnosis, so this is often attributed to gastritis or gallstones. We teach them about the normal blood tests, so do not be reassured by the fact that your blood tests are normal, your ECG is normal, your chest x-ray is normal. If this crosses your mind because of something the patient has said to you in that history, you have to go and get a CT scan. Every time we do a board round, that's three times a day, 24 hours a day, 365 days a year, we talk about every patient with chest pain and whether they may or may not have an aortic dissection and why. So this teaching is continued throughout the time that these doctors work in my emergency department. So as I said before, we see 200 adult patients a day. In the last few weeks it's been more like 240, so we're very busy. And up to 30 patients a day will be seen with chest pain. And what we needed to do was lower the threshold for asking for a CT scan of your aorta. So in 2011 we did 20 a year, so that's just about two a month. And we increased that to over 200 last year. So we had to lower the threshold and we had to speak to the radiology team about why we needed to do that. If one of the juniors picks up an aortic dissection, I tell them that they've graduated the BRI emergency department because they've learned what I've told them and they've gone and put it into practice and they're always so pleased because they've picked up something that's life-threatening and that patient has been given the best chance of survival. One of my junior doctors, one of the SHOs, picked up two in her last six months. One in the first week she was there, in a patient that was in the queue, so crowding in the ED is very common and she came and said to the consultant, this history does not fit with any of the things that I normally see, heart attack, pulmonary embolus, pneumonia, I'm really worried that this chap's got an aortic dissection. His dad had had aortic surgery for an aortic dissection but he didn't know that, he just thought he'd had a valve replacement and the last day of her job, the night before she left to go and work somewhere else, she picked up another one. And how do I know that we've been successful with our teaching? So it sounds like it's quite vague and a bit woolly to teach everybody. We've had no misdiagnosis of aortic dissection since we put this teaching program in. And we make the diagnosis of aortic dissection about once every two months, but they don't come nicely spaced out. So sometimes we have two in a week and then we don't have any for three months. And I'm just going to re-do this because you won't be able to see it. So I knew we'd change culture at the BRI when a patient was sent to our GP support unit, that's another unit where patients are seen who are referred in by their GPs, and he'd been sent for a chest x-ray by that GP. And the history given was chest pain which radiates to the back, severe enough that he'd drop to his knees, now hypertensive. And the radiologist reported this film and said, the heart size is normal limits and no focal lung lesion is seen. history is consistent with aortic dissection, I'm phoning you to organise a CT scan, which is what happened for that patient. We've done a national campaign, I chair the College Safety Committee, this isn't a problem that is isolated to the Bristol Royal Infirmary, this diagnosis is missed across all the UK EDs and so we have done some safety bulletins, this gets sent out to 12,000 members of our Royal College and we've also done some podcasts which we'll talk about at the end, which have been downloaded over 5,000 times and have been our most successful teaching that we've done to date. I'm just going to hand over to Mark. Thanks, Emma. I'm a clinical radiologist, and the key is in the title. Clinical radiologist means that I'm a clinical doctor still, and often radiology is not seen in that point. Clinical radiologists want to make a difference, and this is an opportunity to make a difference. So what I'm going to do today in the next 45 minutes is talk about and dispel some of the myths that continue to precipitate across the UK and reasons why we don't do the optimum image. The first is everyone will tell you you need to get a chest x-ray. If you think you're not able to do dissection, get a chest x-ray. Why? Actually it's normal in 40%. So you're doing a test, we've got a one in two chance of it being normal. And if it's normal, it's not going to add or take away anything from the at all. But what are the abnormalities? Are they barn door? If you find the abnormalities are you reassured that you've got the dissection? Well widening of the medial spinal, subtle. Abnormal cardiac contour, very subtle. So you're going to be normal with subtle or very subtle findings. Don't do it. Ah, ah, but I asked the registrar, why do we do a chest x-ray? Well we need to do a chest x-ray because we need to exclude any other pathology. Really, so we're going to not do it, we're going to do a chest x-ray preventing us getting a CT scan of the thoracic cavity which contains the heart and aorta, which is the best way of imaging the chest, because we might think we find something else in the chest than the chest x-ray. What other pathology are we going to find on the chest x-ray that is going to prevent us doing a CT scan? Absolutely none. So don't do it. Chest x-ray takes time, it takes about two seconds to do the chest x-ray, but you've You've got to move the patient from the emergency department to the radiology department, to in front of the radiology things, get it done, get the patient booked in, do the chest x-ray, come back, make sure it's fine, send them back to the ED department. About an hour, if you're looking, it'll do good for a two-second organization. This is a chest x-ray of someone with a dissection. I would defy anyone to tell me it's not normal. A normal chest x-ray. So why is it important? Well, it's important because the mortality in this disease is associated with time to make the diagnosis. And the immediate mortality is as high as 1% per hour. Now, I can't give you a statistic of another disease which has a time-related mortality associated with it. So actually, by doing the chest X-ray, you are increasing risk. You are putting a risk in there. That hour has cost you 1%. One person will die because you've made that decision. And how good is CT? Well, it's very good. It's 100% sensitive. There is nothing better than a CT scan for making a diagnosis. So you're going to delay by an hour rather than make the definitive diagnosis. I can't believe this message is not out there. But my colleagues tell me, well, there's a lot of considerations about CT scan. There's the radiation dose. There's the contrast dose. There's do we need to do ECT gating? Well, actually, we haven't got ECG gating on RCT. No, do the scan. Some people say you need to do a plane scan. You probably don't. Cover the whole area, and actually work with your radiologist, because it will pick it up. This is a plane scan, and you can see just on the side, there's slightly brighter, and that's the acute thrombus. So plane scans can pick it up. But actually, if you look at these two scans, you can see the one on the right shows the line, and it's relatively easy to see. Work with your radiologist, because how you do the scan and how you look at the scan is really important to make sure you get the maximum details, but you don't, and ideally, if you've got an ECG-gated scan, it's gonna be really important and you'll see it, but it doesn't mean that the other scans aren't worth it. This is non-ECG-gated. There is a beautiful demonstration of a dissection. Let me just take those other myths through and share them with you. So what about the contrast? Well, contrast reaction is disputed cause some effect on the kidneys in terms of renal failure in about 1 in 20,000 people in the future. No one in the ED department will have a diagnosis that is dependent on your scan that will die in the next hour and that sort of risk. Radiation dose. 1 in 10,000 cancers caused by a CT scan. Yes, but you're looking at a life threatening diagnosis. These These risks are insignificant compared to the risk of not doing the scan. So do the scan, and do the scan quickly, and do it is your first line. Now what is interesting for me, and I'm sorry the colours haven't projected well here, is the contrast of how things are accepted and not accepted. About the same time as there was a real increase in awareness of aortic dissection in the UK, One of the ways of diagnosing a thrombus on the lungs or a pulmonary embolism, the clot that will kill you after your long flight back from Australia, was also picked up and turned over to CT. Now, the number of people who die of massive pulmonary embolism is relatively small. And the number of people with a suspicious diagnosis is very high. And as a medical fraternity, we seem to have adopted CTPA with no challenge and no question, whilst there seems to be huge barriers and resistance to CTA, which looks for aortic dissection. And these are the figures that really reflect what Emma's just said. In 2010, we were doing 23, 23 CTPAs a week, and we were doing 0.3 CTAs for aortic dissection. So massive discrepancy. But no one had said, actually, CTPA is relatively insensitive at picking up CTPA, And why do you want to do another test? And yes, we've increased the number of CTAs we've done to 200. But that only equates to 4.5 scans a week. We do 30,000 CT scans a year in the infirmary. And we're talking about 4.5 CT scans a week, against the 27 scans that we do for pulmonary embolic disease. There is a discrepancy. And there is a failure for us as a radiological community to understand the urgency and get the message across. Avoid the chest x-ray. Do the CT. It doesn't matter what CT you do it. There is no risk that will prevent you doing CT that would equate with you making the diagnosis in an early format of aortic dissection. And work with your radiologist to make sure that that CT is interpreted and turned around and reported quickly. And that's where we've got to go next. So how did we do that? Well, we've maintained continuous awareness. We speak to our registrars. We say, you have to support the ED. They come down. We don't miss people. We tell the story of the 43-year-old man who had a cardiac arrest at home because we've missed the diagnosis. We talk at registrar induction. We get very positive feedback from the ED. Not only do they tell their registrars that they're doing a good job, they'll come around and say to the radiologist, thank you. You saved someone's life. And as a clinical radiologist, that's a major thing for us to hear. And actually we've got two very active cardiac radiologists as well who specifically look at how we move and train this and really work to dispel the myth that actually we should be blocking any form of imaging. We should be opening the door and we should be encouraging CT scan done in the appropriate positions as fast as possible. So not only is it education for the radiologist, it's education for all. We've tried to do that, we've worked with the Royal College of Emergency Medicine, we combined and the Royal College of Radiologists put together a podcast specifically tailored at CT scanning, that's the second one here, it's the first podcast that the RCR put together, we're very proud of what it's done. It's a really huge piece of work which involves ED physicians, radiologists, but much more importantly relatives and patients. It's such a powerful piece of work that I want to start by trying to get the information out there, dispel the myths and get this message through to all radiological departments in the UK. Thank you very much for your attention. applause applause Excellent. Mark, Emma, thank you very much for that very powerful presentation. I think what you've spoken to us about and the thing that you obviously get as a team in Bristol is the first of our two major concerns as a patient association which is addressing the diagnosis in the emergency department and as a patient association we want to say to the Royal College of Emergency Medicine and to the Royal College of Radiologists let's get get this practice replicated around emergency departments in the country. I heard a terrifying story the other week about a trust, I won't say which one, where management decided that in order to meet the four hour emergency department waiting target, CT scanning would happen after admission, which is completely counter to the approach that you guys have implemented and are just doing. So I think we need the support of both of our colleges to actually get these messages out there and we as a patient's association would like to support you in doing that and make that our ask to your professional bodies. Thank you. I think we've got time for one or two questions before Mark and Emma have to run away and leave us. Is that alright? Hello, thank you. Are the GPs allowed to refer patients for a CT scan if a patient has come up with the symptoms of the surgery? Yes, yes. So the GPSU was picked up by the radios that came round. Actually we work very closely with our GP support unit where people come in. They have the same accessibility to scans, we have the same principles around what we do. What we are trying to do is so different to what I've just heard actually, because targets are one thing, but actually, if you have a patient-directed, safe culture, then your targets will fit into place, because you're doing the right thing at the right time. And so actually, we won't, we will take, if someone thinks they've got an aortic dissection, we will scan you from anywhere. Because I believe that, well, I'm not going to name my GP surgery, but I've been told that they are not allowed to record. Some GPs aren't. Some GPs aren't. GPs around Bristol are. Why is that? And should that not be across the board? We educate the GPs as well, so we've been out to teach the GPs because we've had a few patients who have had this episode of pain, the first port of call has been their GP. So we've taught lots and lots of different groups of clinicians, so GPs, the medical team, the cardiologists, because we will all see patients that present because it presents with such a common symptom. And so the patient will be sent to the GP support unit, which is the sort of way that they will get seen, but they will have the same access to the test as the ED do. I think if the patient, if they seriously thought the patient had a dissection, they would send the patient down to the ED anyway, because we would need to put them in resus to manage their blood pressure and things like that. We have a lot of work to do with GPs as well. Yeah. Okay, we know that. Thank you. One more question for Mark and Emma. Anybody got anything, a burning question? Good afternoon, forgive me, you may not wish to answer this, but as clinicians, do you find there's a little resistance on budgetary constraints? Because I was diagnosed after a wait of nearly four days, and they said CT scans are expensive. No, none where I work. That cost has never been mentioned in terms of increase in resource. It was all about needing to understand why the resistance was there, but it was never a cost issue. And never should be. And a CT scan may be expensive, but a four-day stay in hospital waiting for a CT scan is far more expensive for lots of different reasons. I wish you well in your endeavours. I wish we had your people down in the south of England. Thank you. applause you