[Music] [Applause] thank you um good so one of the things that's always struck me about any talks on a sustained of thoracotomy um is often it's kind of a you know there's not very much evidence so a lot of opinions so I'm um certainly going to try and just show you what we've seen in our data mum because that's clearly a way better way to uh you know plan things and and understand what's going on is to actually observe it rather than simply opinions so um there's been a lot of people involved on this side putting the data set together that I'm going to be telling you um about what it means so I just want to acknowledge all the hard work that goes into that um right so the talk is about the sustainative to our economy but actually it's about traumatic uh arrest um and right from the start I want to just Define what I mean by traumatic arrest so the standard definition of traumatic arrest is is a patient who is unconscious totally unresponsive to any kind of stimulus um and you can't feel any central pulses in them so you can't measure any kind of cardiac output whether it be by feeling for a Carotid pulse or trying to measure a blood pressure um the term traumatic Cardiac Arrest which is is often used is probably not completely accurate because you know by definition Cardiac Arrest like a normal medical Cardiac Arrest means the heart is actually stopped like it's gone into VF or or asically or something is actually stopped with intraumatic arrest that doesn't need to necessarily be the case it just means there's actually no cardiac output so all functions that rely on cardiac output stops her brain function everything they might have stopped breathing they might not have pupils that are acting but they might still be a little bit of Science of life but you can't actually measure any cardiac out but and I think that's important and I will come to that later why um traumatic Cardiac Arrest is actually a relatively common cause of cardiac arrest overall clearly the majority you know is medical Cardiac Arrest but traumatic Cardiac Arrest isn't uncommon on our service um London's the ambulance one in 10 patients that we go to are in traumatic arrest when we get there and we're seeing about one patient a day who's in traumatic arrest so our service seeks out those you know the serious injuries in London but that's about our how busy we are about one of these a day um and there's something also that's uh is worthwhile knowing especially if you are listening from an in-hospital kind of um Viewpoint is people the the majority of traumatic arrests um happen pre-hospital so if you looked at everyone and has a traumatic arrest only about 80 75 80 percent is not that clear on the exact percentage but it's about that um happened pre-hospital and these patients often what they don't get into any kind of trauma databases not in England and not in any other European countries not in America not in Australia they're going to police records but they don't go into our tan database and those kind of things so actually it's quite an invisible population of people that die from a medical problem um that we we don't really understand the exact size of it um so that's also just something to bear in mind because you know you might feel like look some of the things I'm talking about are exceptionally rare and and they might be very rare in your hospital but that doesn't mean they they rare in your city or town um so this picture over here is our London ambulance team working on a young man who's been stabbed in the chest and he has a cardiac tamponade and he's in traumatic arrest and he's died and they treat him um with a pre-hospital resuscitative stereochotomy and he does well they get a return of spontaneous circulation it gets to hospital he survives to go home fully neurologically intact and I think the really really interesting thing about this picture for me and this is completely true is if you if you look down at the date at the bottom you'll see it's Christmas Eve in 1993 so that's um you know a good nearly 30 years ago and this patient was actually London's ambulance's first Survivor from a pre-hospital thoracotomy they've been trying it for a couple of years and hadn't had any success and then this was the first one that survived also interesting this is 30 years ago and found a treatment for something that is a hundred percent lethal and uh and it's still nowhere near being a kind of mainstream intervention um and there's very little probably the reason for that is there's very little literature in that to support it out there um a couple of years ago the um European resuscitation Council published a new um guideline for traumatic arrest uh and it's good and they acknowledge that especially in areas like this there isn't much literature to go on so still a lot of expert opinion on elements of it but they make some key points that were really important points to to clarify that the first key point is that the treatment of traumatic arrest is not the same as the treatment of medical arrests so your priorities are not early CPR and early defibrillation the next thing I make is that what the priority is is to treat the cause um so your absolute priority if someone's been injured and the interest is to try and figure out what caused the rest and then to directly treat that and I'm sure all of you know there's um four reversible causes or potentially reversible causes so asphyxia or hypoxia um hypervolemia so bleeding tension pneumothorax and cardiac tamponade and then they go on to mentioning this box in the middle that the treatment for tamponade might well be surgery or thoracotomy and the treatment for exsanguination might also involve thoracotomy and then it's got a little bit on that but this is where the uh the the the literature is starts getting a bit thin so whenever there's not much um evidence behind something then there's clearly lots of controversies and uncertainties so the ones that are still around in in pre-hospital thoracotomy are is it futile um and if it isn't futile then who are the patients that can potentially survive and how do we identify them um is this something that should be done pre-hospital or should the pre-hospital systems rather spend their efforts and money and time trying to get patients that need this rather into a hospital and if we're going to try and get them in hospital then should it be in the emergency department or should this be done in the operating theater and last there's always this question of is this only um an intervention for penetrating trauma or is there any role for this in blood trauma and I'll try and answer all of these uh four key questions and try and answer it with data from our service here laughs so what we've done is um we've looked at 21 years of pre-hospital thoracotomies in London done by London's air ambulance and we've collected all that data the main outcomes we've looked at we've used the utstein template guidelines of how you report Cardiac Arrest pre-hospital Cardiac Arrest um so our main outcomes our primary one is survival to hospital discharge and secondary outcomes are survived the event so um for those that don't know so survive the event means you have an arrest you resuscitate them with a thoracotomy that's successful you get a you know a cardiac output back a blood pressure back and you're able to take that patient to hospital and they maintain their own blood pressure unsupported and you hand over the patient to the hospital uh who has an output but then they later die in the hospital so that that's you know they didn't survive to hospital discharge but they certainly survived the resuscitation attempt um and another secondary outcome is for those who survive to hospital discharge we looked at uh whether they survived neurologically intact or or not um another outcome we did look at it was survival to six months and to two years and what we found was uh there was no difference anyone who survived to hospital discharge also survived to those two time points so we've dropped them off because they're exactly the same so if you survived to hospital discharge from from these injuries then you will invariably make it to two years um and a little um just background on what is the intervention we're doing because there's lots of ways to do uh chest surgery you know there's sternotomies the historicotomies there's left laterals there's clam shells so I think it's important to know what the technique was that we were doing to understand the results so in our sop on London's ambulance the first step I put it as a step notice kind of a pre-step is is to do bilateral thoracostomies so you want to exclude uh tension pneumothorax as a cause for your arrest um and we do that with bilateral forecostomies we try and aim to get them both in the fourth intercostal space and if there's no response to that if there's not an immediate return of uh circulation then we continue on uh to the our economy if it's indicated uh and the first step is to do a clam shell thoracotamy there's a picture this this is our the pictures of our training dummy how we train all the um paramedics and registrars on London's ambulance how to do the procedure um so that's what the the incision through the chest looks like and that doesn't save anybody's life that's just to allow you to get to the business end of it and and uh and treat it but you can see that that gives good access to the heart good lighting you know good exposure you can see the anatomy how it you know would normally look in a in a textbook considering that most people doing this procedure aren't surgeons who who are doing this regularly step two then is to open the pericardium so the heart is inside a Sac it's quite a fibrous Sac it doesn't have any elastic in it so that's why if the sac fills up with blood then um the heart can't beat then we call that cardiac tamponade so the the second step in this procedure once we're in the chest is to open that pericardium we use an inverted t uh shape so that we can take the or deliver the heart out of the pericardium and and evacuate any clot or blood that's in there and therefore allowing the heart to beat freely again step three is there must have been some kind of wound in the heart that was causing the bleeding in the first place so that would now start bleeding and you need to tackle that wound and then and there's a number of methods and I won't go into those methods but we we use the simplest methods possible just to control a heart we're not trying to do fancy definitive repairs so sometimes it's just a stapler or just putting pressure on your finger sometimes it's a vascular clamp or something whatever gets the job done the quickest and then the last step is you know in some cases if you get there quick enough the heart will just automatically start beating again and that's ideal and those people usually do very well in others they've been in a rest for a bit too long and the heart doesn't start to gain uh when you take it out of its sack so then um we need to resuscitate it and how we do that is open massage of the heart two-handed good quality massage at the same time occluding the descending aorta so you're keeping all the blood that you squeeze out the heart within the aortic Arch so that it can come back down those coroneries and oxygenate the heart to try and get it to start beating again and the third element is um to make sure there's enough volume because some people would have arrested from tamponade some will have arrested from exsanguination and clearly the exsanguinated patients they've got an Mt system so you would also need to um fill them up so three important elements to the internal substation is aortic occlusion good quality massage and volume resuscitation so that's our technique um these are the numbers so we saw over that 21-year period we saw about 46 000 critically injured patients of which 600 of them needed a resuscitate of thoracotomy so don't know what your pre-conceived uh ideas are on London's ambulance a lot of people think we're doing this on everyone but actually it's just about one in a hundred people that we see would uh we think need a thoracotomy and if we look at all those star economies to actually the cause for their arrest 105 had a pure cardiac tamponade uh 418 was from Hemorrhage and exsanguination and the 72 had both tamponade and dick sanguination so I'm going to talk first about that overall tampenade group and uh talk about that in detail and then we'll go on to the exsanguination group because they are two completely different disease processes different physiology different everything so I think lumping them together just uh doesn't make any sense and you can't figure out you know what you're meant to do if you're trying to lump it all together so the first question that we really have when we looked at this is if you have tamponade patients of someone with an injury that causes tamponade like how long do you have to actually um save their life like when do they die and this goes on that question of where should the resuscitation be happening is it a pre-hospital thing or in-hospital thing or in theater thing so everyone in this uh violin plot chair is a cardiac as a patient who's got an injury that's caused cardiac tamponade and at the bottom it's got time and this is time in minutes from there well the point of injury is it's the 999 times so the closest we can get to knowing when someone got injured um and you can see uh the the bands or the the um quartiles so that the thick band is 50 of them and that's at 11 minutes so half of people with a tamponade will have a really arrested by 11 minutes okay so they die very quickly after the injury and the second line is the 75 and you can see that's at about 20 minutes so 75 of people who have an injury that causes tamponade will have arrested by 20 minutes now I don't know uh well I I do know that even in the quickest pre-hospital systems uh we're not getting patients into a hospital within 20 minutes I think most of our systems we're looking at 50 to 60 minutes to get into hospital if we really quick on scene um maybe around 40 minutes to get into hospital we certainly know any of the front doors of the hospital by 20 minutes um the next thing to look at um is the survival so that's probably the most important uh slide in the in this deck and this is a different um time along the bottom so this time is not starting at the 999 time this time at the bottom is starting when the patient arrests okay and then we're looking at how long until they get the thoracotomy and what their survival is so what we're seeing here is a few things if we do the thoracotomy at the time they arrest so witness the rest arrest in front of you the survival is more than 50 percent but very quickly it dives off and actually there's no survivors Beyond 15 minutes so if they've arrested and in in arrest for 15 minutes and then you do the Tho economy then you're not going to get any survivors and anything beyond that so what we can see is overall survival if you take any comers even if they had the thoracotomy 35 minutes after arrest our overall survival is over 20 percent um and um the other thing he has I haven't split the blunt and penetrating but they're exactly the same so the overall survival of blunt patients with uh cardiac tamponade is also above 20 and it's the same there's no significant difference between the survival from penetrating and blunt we'll get to that at the end of the talk again but nice to highlight at you um this graph is the same data but I'm showing all the outcomes so the black is patients that died on scene that are pronounced life extinct unseen the medium gray is the ones that survived the event so you've got a good Rusk you got them to hospital with a good cardiac output but they died in hospital and the light gray is those that survive to go home okay and I've changed the time at the bottom into categories rather than continuously um so what we can see is if you do it in under a minute as we said about half of them survived but nearly all of them survive the event so only a very few um are you know die on scene similarly if you do within five minutes but then rapidly tailing off after that and if we actually look at just the first 10 minutes after arrest when most of us know from medical cardiac arrested you know if someone's been in a rest for longer than 10 minutes without any defibrillation or CPR then the the outcomes of dismal so if we look at the first 10 minutes of someone who's had a traumatic arrest actually the average survival is over 40 percent if you get it done in those first 10 minutes and about three quarters of them will make it to hospital with a cardiac output so I'm quite good um I don't know what anyone thought before of the outcomes of um of of resource date of thoracotomy but you know clearly this is an effective intervention for people who have actually are in arrest this uh these pink um ones are the ones with the poor neurological surveillance I've divided the survivors into those with good neurological outcomes stay the light gray and then those are the poor neurological outcome that are the pink color and what you can see is as you would expect this is related to how long they've been in arrest so the longer someone's in the rest you you might get a Survivor but there's more likely that they'll have some neurological damage after that one thing I would say though I I know if you um patients that have had poor neurological you know on our scale we use the CPC scale for anyone interested in the research side so the cerebral performance categories and we say poor neurological survival as a CPC score of three or four so we we have a few survivors that are cpcs three or four uh that keep in touch with us and their families keep in touch with us and what's really taught me is that um shouldn't judge you know someone's Quality of Life by your standards these people are on the whole really happy to be alive yeah their lives have been changed drastically but they are happy to be alive they enjoy life they get a lot of pleasure out of being alive and so do their families so you know we show these graphs and you you the instinct is to say well you know maybe we shouldn't do it Beyond 10 minutes because probably we have quite bad brain damage but those people still um would rather be alive than have died what's the survivable window then um so we've seen from the graph that in a very good survival if it's done within 10 minutes but we do have survivors up to 15 minutes after arrest uh but what's really difficult for the paramedics and the um the hems Crews that I work with is when you arrive and you've got to make a decision to do this big procedure you've got to make that decision quick you don't have time to think about it and gather lots of information so you're arriving and all the information being given to you is very uncertain it's chaotic you know there's there's and it's very hard to judge whether you're within that time window you know you know some people are saying it's been just two minutes and and usually when you look back it's been a 15 minutes and that says really hard to know if you're in a survivable window so one of the things we looked at in our data set was whether there's any other ways to um help make this decision now the obvious one that a lot of people will put out and I I support it as well is that you just have a look with a ultrasound and if you see cardiac activity then you you know that you know you're still actually within a survival window and and that's fair enough but um I think most of you um using pre-hospital ultrasound will realize that it can sometimes take you know four or five minutes just to get the thing switched on and probe connected and ready to go and you don't really have that amount of time um you know they might have been in a survivable window and if you spend five minutes doing something then they could be out of it by the end so we looked at the ECG um and there's two reasons for this there's one we slightly slower to respond and on London's a ambulance than the London Ambulance Service you know they're usually a London Ambulance Service um ambulance or response car will get to the patient before we get there on the helicopter um and from medical cardiac arrests we always want to put an AED you know we push to early defibrillations they usually have some kind of monitoring on whether it be an AED or connected up to the um to the Monitor and certainly our dispatchers can speak to these teams um they know that we're on the way and if you can give them some some ask them to do some things that are going to be helpful I'm sure you know they'll appreciate that and so we we've started asking if they can just have the monitor attached so that as the crew arrive they can look at the um the Monitor and see what the ECG rhythm is and the reason for that is is um what we found is at the point of doing the thoracotomy when when people decided to do it we looked at all the rhythms that people were in and um they were basically only two rhythms either they were in because none of them had a central part they were all in traumatic arrests so unconscious with no palpable Central process they all were either in Pea or a systole but we pea is kind of an unhelpful term because it's a bit of an umbrella catch-all term so we broke those peas down into what the actual rhythms were so it could be you know narrow complex Rhythm or could be a narrow complex bradycardia or could be an agonal Rhythm you know just these wide complexes with no proper shape to them or true a systole but there's nothing on the monitor and we looked then at people we broke them down into what Rhythm they presented in and looked at then how long they had been in a restful to see if the ECG Rhythm could tell us anything about how long someone's been in a restaurant so at the bottom is minutes that someone's been in arrest and what we found is if you had a narrow complex tachycardia or a normal speed heart then you're usually only been in arrest for one or two minutes okay so you don't even rest for a very short time if you still at a narrow complex if you are starting to slow down bradycardia then you've been in the rest for about three minutes if you were in a wide complex Rhythm you'd been in a rest for about on average about seven minutes and if you'd already got a flat line then you'd usually be in an arrest for more than 16 minutes about that so what so very close correlation here between the ECG Rhythm and how long you've been in a rest so that's quite helpful in trying to make let you make a decision on how long someone's been in a rest but we wanted to see you know we know that the time you've been in a rest correlates directly with your chances of survival and now we've seen that the ECG Rhythm seems to correlate with the time so the obvious thing then is that the ECG Rhythm should then correlate with your chances of survival so we looked at that next and it does so um those that have a sinus rhythm have a chance of survival of about 60 percent and once they slowing down that drops to about 35 percent and when it's agonal you know in a high 20 and quite a low chance of survival when you're in a systole but not zero so we've had good well we've had survivors who have a flat line with tamponade and again I've added um just to the um to the survivors those with the poor neurological outcome and and the same thing so we knew that that's related to time so so the worst rhythms you know the longer you've been in in arrest for the more chance of having an unfavorable neurological outcome but we did have uh you know patients who in asystally who survived and fully neurologically intact but okay so that's helpful move on now and talk about bleeding because that that's the bigger group actually about a fifth of all of our patients were tamponade and about four-fifths were um were were hemorrhage and go through all the same stuff so how long does it take for someone who's bleeding uh to arrest so again just to recap this time at the bottom is the time from your point of intro 999 times the closest we can accurately like um get to when the injury might have occurred to the point that you go into traumatic arrest and actually it's a little bit longer than the tamponade so the tamponade's arrest quicker this is slightly longer but not by much so half of the patients are in Cardiac Arrest by about 12 or 13 minutes and certainly three quarters of them have arrested by about 23 24 minutes after injury so like yes some do arrest at 60 minutes after injury but you can see that the vast majority are going to arrest during the pre-hospital phase before you can get these people into hospital so again if you really want to have an intervention that's going to be meaningful it's going to need to be applied during that pre-hospital phase of care it's just not possible to get patients into a hospital um that fast um this is the survival okay so and I think I got a compare yeah here's a comparison of the two so an order of magnitude difference in surviving if you've got tamponade versus if you've got exsanguination so two completely different diseases and uh overall this is about less than two percent chance of survival uh out of 400 and plus patients and no survivors Beyond five minutes um and there's a there's a couple of things just to you know note from here the pathophysiology is quite different so tamponade arrest you've got a really you know you've got a relatively healthy heart beating away and there's blood accumulating around it and then the pressure builds up and then uh you know blocks off you know the pressure on the right atrium will uh collapse it and then you have no preload and then the heart stops so actually the heart's been stopped in quite a healthy condition uh and then they can't do anything so just stuck in that condition until uh hopefully someone gets there and can release it where's exsanguination the heart has no blood to pump and therefore can't you know there's no coronary flow because all the hot oxygen delivery occurs in diastole it can't produce any kind of blood pressure so this heart is not getting any oxygen and it's beating away as fast as it's ever beaten um and it'll keep going you know somehow uh for 10 minutes or whatever and until it's absolutely wrecked itself and beats its last beat so the physiology of the of those cells and that is is so extremely deranged that um by the time it stopped there's you know almost or if not impossible to um to resuscitate this patient anymore or that heart anymore also I just mentioned you know the technique and that's why I mentioned the technique the technique we're using the primary aim is to treat tamponade so it's not primary aimed at treating exsanguination so you know there's a bit of a bias in that our our um technique is prioritizing releasing a tamponade and not prioritizing treating hemorrhage here is the um the bars of all the outcomes so just recap again we've got black or the people who die on scene um the light the dark gray is the survived events so they make it to hospital but then die and then the library bars are those who survive to hospital discharge and on the left is the cardiac tamponade and on the right is the exsanguinations and you can see across all the outcomes how different they are between these two diseases um and on on the exsanguination side you've got only got survivors in the first five minutes um they are you know about half of patients might survive to hospital if you do the thoracotomy within five minutes of arrest I think that this is people who arrest in front of you you know if you're doing a thoracotomy within a minute of arrests invariably they've arrested in front of you and you're getting a survival of you know two or three percent you know half of them making it to hospital the majority dying and anything beyond five minutes pretty much all of them die on scene it's not possible to even get a Rusk so on the whole I think my take home from this is that the thoracotomy that we do uh you know the procedure I outlined is not an effective treatment for um for those that exsanguinate um I just I'm just kind of quickly skim through the chat and see if there's any questions before I'll move on to the next section um let me see it right okay nothing uh we'll get the questions uh off to it then um right so the next thing that I thought we'd do in our research was actually look at ourselves our survivors and see if there's any lessons on how to improve this going forward so out of 400 plus patients we only had eight survivors from exsanguination and these are the eight tabulated out and what we found was interesting okay so the first thing is that all the survivors had penetrating trauma mixture of stabs and gunshot wounds but um all all penetrating terminal the two percent survival from penetrating trauma versus a naught percent survival from blunt is there's no in in a population of 450 patients there's no difference statistically between those two numbers so it's not to say blunt can't survive though we haven't had a Survivor so the penetratings are the ones that we seem to have managed to um resuscitate The Cider the hemorrhage was all over the place so you know you might say well the people with bleeding in the chest would be the most likely ones to survive because you get in the chest and you can hopefully try and stop that bleeding but actually we had lots of survivors who were hemorrhaging in the abdomen even from you know femoral vessel injuries in the thigh and even um you know one in the neck but these are the really important things every single person who survived had a narrow complex organized Rhythm on the ECG so there were no survivors from asystole and no survivors from a wide agonal kind of rhythm and as we've discussed all of them were basically witnessed Cardiac Arrest who had the thorough economy done almost immediately on arrest other thing is that all of them had aortic occlusion and I said to you in the beginning you know that's a really important part of doing effective resuscitation but when we looked at all the people who died only about two-thirds had a ought to conclusion so that is an important difference when a hundred percent of your survivors had it but only about two-thirds of the non-survivors had it so that's something that maybe we thought might be helpful and because most of them had a beating heart quite a few of them didn't need internal massage some of them did because the heart was beating feebly so the clinicians helped it along with some internal massage but some of them was beating fine and they didn't need to do any internal massage this is the other really important point I think is the amount of volume that was given and it makes complete sense you know they've exsanguinated they have no blood left in their system so you're gonna uh you know this is obviously going to be helpful to fill them up and by in hospital standard you might say that's not much um volume uh but actually if you think about what people carry on them pre-hospital that's everything that the teams have if you're given 3 000 mils of crystalloid that's invariably all of Crystal Lord you carry you see later in the study we were carrying blood or whole blood and they were getting we we either carried two units of whole blood or four units of blood and they were getting all of that as well um so all the survivors had been given all the fluids that the team carried and as far as neurological outcome actually was really really good on the whole if they survived this then they generally had good neurological outcome so I think I'll take home messages on how to go forward with thoracotomy for exsanguination is that aortic occlusion is important and we understand why that is because if you occlude the aorta you immediately improve coronary artery perfusion um and they need a lot of volume and what we've found is we've doubled almost tripled the amount of blood we now carry uh on us and and now so we can give a lot more so now we can give eight or sometimes even 12 units of blood pre-hospital and what we found is just since we've been doing that which has only been for maybe about two years we've already had almost the same number of survivors from thoracotomy from exsanguination so you know it's not it's not like complex but you know refilling and exsanguinating patient with a lot of volume and then they you know they survive so um those are our take-home messages so what's the survivable window again we wanted to see just you know if we could use the ECG as well in the in the exsanguinating patients as well as in the um as I showed in the tamponade patients so again interestingly only two rhythms uh we weren't seeing VF or any VT or any other kind of rhythms we saw them later in the resuscitation so often when you're resuscitating a heart and you've you know you're given some adrenaline and all of that then we might you know we did see that some patients came back by going into VF first and then went back into a rhythm but the rhythm of the arrest was either Pea or asystole um slightly different times for this so a little bit shorter time so the people who were in a narrow complex normal speed Rhythm had usually been in arrest for about a minute similarly the ones that were slowing down and also actually on average been in a rest for about a minute agonal rhythms had been in arrest for about five minutes and asystole um usually someone had been in arrest for more than 10 minutes and then we looked at whether this correlates with outcome and what we saw again was exactly that that the only survivors were if there was an actual narrow complex Rhythm um so just to end the last point I wanted to discuss and then we can go on to questions was this question that always comes up about whether it's just for penetrating trauma or whether it's for um blunt trauma and we took all the data we had on all the variables we looked at every variable we had and saw whether it was related uh on a univariate analysis so just looking at that variable and surviving to go home whether there was any relationship and then we put every variable that was associated with survival into a um a regression model that you can then see because sometimes you know two variables are measuring the same thing as by the same process that their um they're associated with survival so then we can see which ones after adjusting which are the true um measures that are associated with survival and um what we found was only two factors out of all the factors like whether it's a witness to race what the ECG Rhythm was whether they had CPR before whether they got given adrenaline we put everything in only two things came out as being significant one was what caused the arrest was it tamponade or was it exsanguination or was it a mixture of the two so that was very very strongly associated with whether you would survive so adjusted odds ratio of nearly 30 so 30 times more likely to survive if you had tamponade over um exsanguination and the second really important factor was how long you've been in arrest and again really big odds ratios here so nearly 20 times more likely to survive if you had been in arrest for either less than a minute or one to five minutes and then dwindling off very quickly and non-significant after five minutes all other factors we found were were related in some way to one of these two factors so I've shown how like ECG rhythm is related to how long you've been in a rest for and similarly we found you know if you've had external cardiac massage that's usually related to how long you've been in cardiac arrest for for people who've been in arrest for some time before the hems team arrived will usually have been getting some CPR whereas those that are witnessed by the hymns team to arrest and get their thoracotomy immediately usually haven't had external compression so the relationship with external CPR was reversed you're more likely to die if you got external CPR was probably all because it's just related to how long you've been in a restaurant and same with adrenaline the the relationship was the opposite way around you're more likely to die if you had adrenaline I don't think that's a direct effect of adrenaline I think it's just you're more likely to get adrenaline if you've been in a rest for a number of minutes it's not the first thing we usually give for a rest so my summary from all of this is basically traumatic arrest you know it happens very soon after an injury so from tamponade and for examination if people have injuries that can cause those two things they will die usually within 10 to 15 minutes of the injury and this makes it really if we want to make any difference something that we need to intervene in the pre-hospital phase because that really the you know even the fastest responses if we're getting there in five to eight minutes time you know they're really many of them will have already arrested uh um but we certainly we're not in any position to be having these people arriving in the hospital then the sustain of thoracotomy as I've described it is uh and uh I think you'd agree and I'm happy to chat with you about it but it seems to be very effective treatment although time critical it has to be done within you know 10 to 15 minutes but are very effective for people who die from tamponade considering that no treatment is 100 death and we're saying you know we think there are in our 21 years experience is about 40 survival if you do it in 10 minutes but not very effective for exsanguination I think that's fair to say two percent survival probably two percent would survive if we hadn't have done it by chance and there's many ways to um you know to help with this decision making I haven't gone into detail on the decision makers clearly uh you know a decision that needs to be made fast and accurately and there's a lot to be gone into but I think the ECG can be helpful in informing us to make the decision and also telling us about what the likely chance of um Survivor would be so thank you uh very much and let's um I'll open up the chat box I'm happy to take any questions there's quite a few in the Q a lot okay right okay so I'll just start from the top so do we ever defibrillate uh rather than heart massage in the um the fourth step of um of our resuscitation and the answer is for me no um I find that uh you know the as I said most patients aren't in VF um and those that go into VF is usually whilst you're trying to resuscitate them um is usually an irritable myocardium because they're hypoxic so I keep on with good quality massage aortic occlusion and volume resuscitation and although a lot of people will tell you that VF can't automatically um you know come out it does you can you can you can massage them through the VF you get you deliver oxygen to the heart and it will start beating again and get a coordinated rhythm in the majority uh that said though I've certainly have defibrillated some and but usually if if they just won't come out of the VF you know you're doing good quality massage then VF is getting coarser and coarser it goes other way if you've got good quality massage um but sometimes stubbornly just won't go into an organized Rhythm uh and then yes we close the chest down uh pre-hospital and give an external shock and try and get it into a to a rhythm but on the whole I'd say you can massage internal massage through VF um so next question uh yeah because this is a question about um the differences in survival from knife uh penetrating injuries and gunshot injuries um that's a fair question and I suppose you know I trained in South Africa and I think we we're lucky that there's not a lot of gun crime here because because bullets do far more damage and far more complex to um try and save these people and certainly far more of them are unsalvageable so uh yes I think there is a difference but as you saw in our data um from the examinators we have had survivors from gunshot wounds so um but thankfully we don't see them that often um so about treating tamponade and and examination on scene if you don't have the skill set to perform thoracotomy um so it's sometimes quite hard to tell which one you're dealing with because if you've got a penetrating injury to the chest you know it could be could be either obviously if you've got a penetrating injury to the groin or something then the only uh the thing that it could be is exsanguination and certainly early Basics are life-saving in exsanguination and in London uh one of um our hymns Consultants clear park has been training our um our rapid response police force so that the people who go to all the gun crime and that in some you know applying tourniques applying pressure dressings doing it properly um and it's the effect I think has been really uh all of us have noticed it because they get there much quicker than us they get there much quicker than ambulance service because they go straight in they don't have to wait until it's been made safe and um people that would certainly have been dead you know with injuries to you know femoral arches since I've got good tourniques on quickly and um and they do really well so I think if you treat if you can stop bleeding as quick as possible then you avoid even needing any of this um this stuff um next question is uh do we cross clamp the aorta um so we don't we we just teach people to manually compress their aorta with their hand um cross-clamping whether you manually compress an aorta or cross clamp it it has the same effect but cross clamping comes with a lot more risks if you don't know how to do it you can do a lot of damage the other thing with a cross clamp is if you forget it on you create a lethal ischemic injury you can't have the aorta occluded for you know much more than 30 to 40 minutes and that would be easy to do with a clamp on you know you put it on pre-hospital you lose track of the time you're taking them to hospital and next thing you know no one wants to take it off pre-hospital because you're worried that they might arrest again and then it's been on too long and then they just can't survive with manually compressing it gets a bit tiring so whoever's doing it will usually start doing a bad job after about 10 minutes and that kind of allows some blood flow through so there's kind of like almost a safety valve there um Airway management yeah so it gets done second um or um you know whoever's on scene does the best they can with whatever skill set they've got so if they can tube you know the patients in arrested only drugs and they can do that or quite happy to just put an agile in so probably the majority get an agile or if people don't know you know if you've got a really junior team and they're not happy that just um bag and mask um you know you've got to there's no point if the oxygen is not going to go anywhere then it is you know coins you've got to get that heartbeating and pumping blood around and then you know you can work on attaching oxygen to the blood which part of that water can be cross-camped so we do the descending aort usually don't have much Choice it's just the part that's in front of you um the important thing is the aorta is under the lung so you slide your hand posteriorly along the ribs till you hit the um spine and you just pull all the soft structures lying on the spine down onto the spine on the aorta will be in amongst that and you'll include it um so how long can you safely include their order so my advice to our teams is is you know you you'll include their order until you get a Rask so you do good quality uh cardiac massage analytics until the heart starts beating on its own and then my advice is to not really keep it on for longer than 10 minutes after that because that 10 minutes once it's beating on its own will be enough to have good coronary perfusion and try and get the heart into a better State when you let go certainly distal bleeding might start increasing a bit of mine not maybe there's some clotting and that's occurred but it might but the heart's not going to immediately stop it'll take time then to get in a bad place and you can probably keep up by now because now you have IV access you'll be giving volume so um I'm really not keen for the um aortic occlusion to stay on much longer than 10 minutes and we've had a lot of chats about whether you know our dispatcher needs to you know maybe give a little you know check in to say you know they know what time their Auto conclusion's gone on and then give you a little reminder at 10 minutes to see whether you've you know starting to think about getting it off again um so as far as guidelines um yeah so we're going to write all of this up obviously but one of the big points with it is um is it I think it will change the guidelines on selecting patients for this procedure um I think quite clearly you can see um probably the biggest group of patients is actually the patients who don't need it so I think what's quite clear is if someone can only have exsanguination as a cause so the stab isn't to the chest or epigastrian it must you know stab into another part of the body either abdomen or thighs or if they've arrested then it can only really be exsanguination if they're in asystole or a you know unorganized wide complex Rhythm then we don't have survivors from that so that's a big group that was actually hundreds of patients in our group um that's probably an unnecessary um thoracotomy clearly if the Stab Wound though is in the chest and it could be tamponade then we have had good survivors from wide complex rhythms and a60 so then you would still go for it because maybe it's a tamponade and then if you see that it's not a tamponade then you just stop and you uh purely then um the other thing I suppose we might change the guideline is just pushing and it certainly has on our services pushing people to just do the procedure quicker when it's indicated um because we've had a lot of near-misses where we've had a witness to rest but it's in the back of an ambulance and or something like that and it's taken some time to you know find a place to stop and take the patient out the ambulance and then find the kids and then start and you know that six or seven minutes that it takes to do that is the difference between a good neurological survival and a and a someone who dies so I think people seeing those graphs and seeing how fast the chance of survival starts dropping after the rest has made everyone really aware that you do really have to get in there within minutes um to to have the most effect um something about you know suturing um and avoiding coronary so yeah we use you know we teach people a horizontal mattress features but on the whole pre-hospital um with teaching people just to staple with a uh with a surgical stapler um or if it's not a ventricle then just to use a a clamp um so if it's a Atrium or atrial appendage just clamp it off or if it's a vessel you know a side biting clamp because you could just put it on and then the bleeding sorted quick and easy and it can be sutured in the in the hospital uh who performs the procedure in our Center so pre-hospital we have a range of different Specialties uh most people are anesthesia or emergency physicians but we get all sorts we've had orthopedic surgeons we've heard you know everything so and everyone who comes on our services taught how to do it and uh and uh undertakes it uh in the hospital we're lucky um you know we have a trauma surgeons 24 7 and invariably um if we have someone coming into the hospital like this even in the Ely there'll be a trauma surgeon there so in the hospital uh I think very often done by trauma surgeons certainly the successful pre-hospital ones then they you know land up in theater and be finished off by a trauma surgeon yeah um so there's a question how about improving decision making and the survivable window yeah it can be difficult to distinguish between tamponade and exsanguination so I didn't present it but our data basically is um if you've got a stab wound to the chest or the epigastrium um there's a 40 chance that you've got a tamponade and a 60 chance on average that it's a exsanguination for all our cardiac arrest so if it's in the chest or uh epigastrian and that's the split now clearly 40 of the tamponade and Tamanna has such a good chance of survival you would almost always if they're within that you know 10 to 15 minutes and give them the benefit of the doubt uh penetrating injuries outside of the Chester epigastrum there's there's no um uh we had one uh temp not from a gunshot wound to the abdomen uh so there's really very unlikely to be a Terminus it's almost always an exsanguination so I think then you can be quite clear that it's an exsanguination if it's not chest to a pedestrian how many patients in our data set were pediatric uh I think a few and it's something we're going to look at separately but um the range or the youngest in that data set is two years old and the oldest is like 99 so there's a big range in that data set um High Prof board they say here's a question um what is our experience of children uh in both scenarios so yeah so I suppose we've we've answered and we do want to dive into that a bit more um I mean the majority of the children in this data set are going to be that 14 to 16 year olds that you know that there's a lot of that age group I think the majority of people with uh that penetrating trauma in this group is you know 14 to 25 age groups so I think it will be interesting for us to look at that um so you have a question about how does you know how do more Junior doctors get opportunities to practice the skill and um how do you avoid getting into trouble so two good questions there so I think avoiding getting into trouble is you need to do if you're going to do this procedure needs to be within a system that supports this um and I don't think your results will be very good doing it outside of a system that supports it because there's a lot of stuff that needs to happen to even make it possible um you know from training and education to carrying the right equipment to do it properly to to getting sent to the right cases and getting there in the right kind of time and to being able to deliver them to a hospital that knows what uh to expect and knows how to take these patients on I mean now in our system we're putting a lot well not a lot but we we put these patients off and on to ECMO uh and then gets you know survivors from that because they do have really really uh you know injured Hearts the myocardium's been injured and I can't cope for the first few days after this um so so they need that extra support so you do need to be in a system and how do you get opportunities to practice well even people who do it you know even the you know the guys who do them and have a survivors often the first time they've done it in real life so the only way is through moulage and training um so we on on our air ambulance service all the new paramedics and doctors they they come and uh either they spend some time either with me or one of the other consultants and we go through the whole procedure in depth we got as you saw some pictures we got some dummies that we can show them all we've got some videos we can show them you can practice some of the technical skills so using the clamps and suturing and using the clips um so you've got to do all that stuff I think really important to be able to mentally rehearse and that's um why I've told you the procedure in such a step wise way because I teach it in those steps so people can think about what they would do and we've really tried to make our indications clear um so that you know decision making can be swift but I think you really have to learn these procedures before you actually you know the first time you do one you need to be able to actually deliver it and and have a Survivor no one gets a lot of opportunities to do these um do you think there'll be any tools or strategies for decision making um in the future so yes and that's where I was going to you know guidelines and that I don't think there's really time to be using AI or any of that kind of decision support but we are thinking about whether we you know we can involve our dispatches getting some information before we arrive to help such as getting the ECG on so as you arrive you can see a rhythm and make a decision from that um so yeah just starting to and and it's much easier now with data to start you know rather than opinion start digging down into who are the group that can survive and then identifying them uh he has something on access so as I said really important to give big volumes so we're not talking you know one unit of blood if you if you're going for it you need to really go for the need a lot of volume um as I showed you know four units in the past probably wasn't enough and probably one of the reasons why we had such poor survival and now that we carry more we're getting a lot more survivors so you do need IV access to do that and you're not going to be able to do it through an i o so do we go Central or in the right atrium so ideally we would like a you know a large more peripheral cannula like an antecubital fossa and sometimes these cases when they arrest um they do actually have decent you know veins for the the first teams that get there are able to actually get good bore lines in our second option often when we get there as the hems team we would start first up with the thoracotomy so the the ambulance cruising that would then would task them immediately we're trying to get IV access um we do carry Central lines as well so that would be our second uh go if we absolutely can't get peripheral IV access then we would go Central which we tend to go for subclavian but most of these patients are penetrating and you know if if the you know they need just whoever is much more comfortable within internal jugular that's fine you know same thing do what you think you can get in fastest and right atrium we teach it and we do do it from time to time but it's really only when you can't get any other kind access but if you're in the chest and you know you've got the heart right in front of you and no one can get any access you you can't be waiting in a minute it needs to happen so if if it's not in within two or three minutes that there's some decent access then yeah and then most of us would put it in the right atrial appendage uh Andy Dunn hi Andy um periods patients unconscious but gasping and bradycarding so that's kind of on our system we've said you know that is pre-terminal and that's exactly when you should be going in so that is traumatic arrest if they unresponsive to any kind of painful stimulus and you can't feel a central pulse they're in a rest don't wait for them to be asystolic and certainly if they slowing down if they're starting to Brady they're going to be asystolic in a few minutes after that so that's your window you really want to um get in there then uh Vivek will yeah so this is about why is it effective and uh is it because of uh coronary perfusion and certainly uh so on the tamponade side it's about releasing the tamponade and if the heart's not beating certainly coronary perfusion will get it going again on the exsanguination side I think exactly that the whole procedure should be aimed about restoring coronary perfusion because the reason they arrest and and you would have seen from those graphs is they go from a tachycardia to a bradycardia to agonal to a systole and that is the response to hypoxia of The myocardium as there's you know it starts let me see it in children all the time their hearts starts slowing down and then as the cyanatrial node and that gets hypoxic you start getting these wide complexes and then it eventually stops so the whole idea is to reverse that and to restore coronary perfusion and that's why I think they all to conclusion is actually really important as well as the volume any indication for thorough Academy of blunt trauma yeah so it didn't probably in our blunt traumas we saw about five percent of the blunt chest traumas had a had a cardiac tamponade so in the penetrating traumas I said 40 of penetrating chest traumas had a had a tamponade so very high chance of having tamponade but in the blood traumas only five percent so 95 it was exsanguination but those five percent of blood trauma patients who had a tamponade had as good a chance of having a good outcome as the penetrating ones so I think that we can't do thoracotomies on 95 of blood traumas who are exsanguinators just for that five percent that might be a tamponade but I think if you either clinically or with ultrasound you know if you out sound you diagnose a tamponade I certainly think you should give blood traumas a chance to have a good chance of a good survival and if the blunt mechanism is one that you really think is highly likely you know like they've been hit in the chest with a cricket ball and there's you can feel the fractured ribs over the heart and or something like that then I think you need to make a clinical decision either with ultrasound or clinically but if you think there's a good chance that this is a tamponade you do get tamponites in blood trauma and I don't think we should um not allow them uh the chance of a effective intervention um KOA management we've talked about complications so so not really the survivors um I suppose yes we do have complications but um they don't tend to get bad wound infections you know we're doing this in unsterile the chest walls very vascular and they tend to heal up really well if they survive um uh the probably the most common complication is it can be a lot of pain from these um incisions uh the the clamshell incision and some of them you know do have some more chronic pain if there's been injuries from either the incision or the stab to the intercostal nerves and that so that's usually probably the most common one is still not that common but see most of the people I see who survive clam shells they're quite you know they don't have any pain in their wound and their wounds heals up nicely um okay we've gone through the aortic occlusion so txa um you know txa is not you know it's not going to really add much benefit to someone who's in arrest um but if you get a good risk uh you know then on the way to hospital I would give them it um because they'll be bleeding from the wound incision and so that can be helpful then uh I wouldn't let it delay getting on with the thoracotomy in any way um obviously in our data set it's skewed because on the whole only the survivors got the txa so yes in the in the an hour when we looked at the univariate analysis txa was associated with survival but that's I think because the only people that were given it were the ones that had at least a rosk um um so he has a question about if you uni if you're doing the HH HTT um principles uh should you do CPR in traumatic arrest while you're waiting for him so yes you you should um I think you know you do yeah so I would do CPR whilst you're waiting for hems but I wouldn't let the CPR get in the way of the interventions to try and reverse the causes so uh do your needle decompressions or if you're allowed to do thorough costumes do them make sure you're giving you know volume resuscitating make sure you've controlled any Hemorrhage so do everything you can um but you know you can do the CPR as well and then certainly I suppose the biggest thing is when a team arrives that can do your thoracotomy you wouldn't delay doing the thorough economy because this CPR going that should just stop then so that the actual um intervention that's going to have a make a difference can be done right um neurological secretly of cardiac arrest well yes if you've been in a rest for too long as we showed the you know the poor neurological outcome and then death is directly related to how long you've been in cardiac arrest for um so he has a question about if you have a good Rusk and the patients start waking up uh what are the considerations for RSI drugs so it does happen but on the whole I find um they don't wake up to being wide awake um they start you know getting pupils you become reactive um they start biting a bit on their tube they start fighting the vents later a bit and and these are you know good signs that this patient's going to do well they don't tend to like open their eyes and that but um um I would simply give some ketamine because that's a good analgesic considering you've cut their whole chest open and a semiodynamically pretty stable drug and if they're fighting the Venture you might uh want to paralyze them with some rock uranium if you've already got uh you know the airway um you've got an eating tube in and they're on a ventilator so that that's probably what I would do um do we only do a sustain of Star Academy on patients with blood trauma where we suspect tamponade I think going forward yes um but in the past no um so I think that's something that we've learned from this data is blunt traumas you need to have a focused reason for doing the procedure so if you see a tamponade in a blunt trauma then I think it's indicated similarly if someone is exsanguinating um and they arrest in front of you um maybe in the future just uh you know a slightly different procedure but a simply a left lateral just to get aortic occlusion on and not doing the whole process of opening up the you know if you if it is if you're sure that it's examination so say from a groin wound or something then uh you know we could use aortic occlusion either you know by by surgically or you know we also use ribowa so there's two ways we can include there also but I think in these very early cases you know 10 15 minutes or 20 minutes after injury is a different population that then what's just come out in the robot trial and it it seems like in those cases to avoid a full Cardiac Arrest that's non-survivable um aortic occlusion probably does have a role just to give you the time to get the volume in and get on top of the volume problem and then to release it um so survivors of penetrating thigh wounds what was the rationale for thoracotomy um yeah the rationale is they've exsanguinated their an arrest um and they got no cardiac output so it's to occlude their aorta to improve coronary perfusion um and to sometimes assist you know with with internal massage to until the heart recovers and is able to beat on its own again so there's a question about um where they would be helpful for ground ambulance Crews to have the equipment needed for the procedure ready for when a hems crew arrive um probably not and I didn't show you the data but actually um on average over 600 thorough economies that we did a time from arrival to the time starting the thorough Academy was about a minute okay and that sounds like very quick but actually if you can't you know 60 seconds out it's it's a long time when this is all happening but um I think that's you know hard to really improve on but considering you've got to make the decision of that so our equipment setup is very simple equipment there's not much in it um so I don't think there's any delay from an equipment side I think things like you know applying an ECG Monitor and having that already so as the team come you know and telling you know there's patients being unconscious don't have any probable pulses how long you think they've been in a restaurant and having you know that kind of stuff that information having a nice and clear given straight away you know we can't listen to a long Handover of like four minutes of everything that's happened it's just targeted information what we need to hear to make that decision quickly that would probably cut down the time to doing the procedure more than um having the equipment ready a question on bleeding mammary arteries after rust yes they do bleed starts squirting usually uh only the proximal ones usually one of them or so again for me that's a really good sign that they're probably going to survive um you're not going to bleed to death from a mammary artery in the 10 or 15 minutes it takes to get you to hospital but the natural reaction of anyone you don't need to be a surgeon is if you see something spraying blood you push on it and that will stop the bleeding so you don't need to do anything fancy we do carry little mosquito clamps and could suture it off but actually on the whole you can just press on it and it will stop bleeding and the surgeons in the hospital can sort that out um Packing Tips for transporting to an MTC um or someone who's had a thoracotomy um yeah so probably need a bit more time to say are some tips and tricks so on our service down here we often load them backwards feet first into the ambulance so that uh the left side of the chest is still available if you want to put aortic occlusion back on um because otherwise you know you're having to lean over the patient too but on the whole hopefully by the time you're transporting you know they've got uh their own cardio carports or their hearts beating again and all you're really worried about is just making sure there's enough volume to go around so it doesn't arrest again how often have I seen pericardiocentesis used as a temporizing procedure um never um it doesn't work and I think I'm lucky working in the system I've done that um people understand that you it almost always is a clot inside the pericardium um and is not going to be able to aspirate the clot out that said in hospital we've certainly had trauma patients that are on Intensive Care Unit and develop effusions that aren't blood um that you know we unsure if they causing compromise you know given there's lots going on often and those you know I think is fair enough to to pericardial synthesis but if it's if it's an acute injury that's bleeding um what you don't want to do is waste a few minutes doing a procedure that's not going to work because um you really want to be doing the procedure that's going to work as you can see that there's not much time to be doing anything else you've only got a few minutes to and it takes a few minutes to do the procedure so uh I think it can be harmful if it gets in the way of doing what's needed and last question um is there a role of Star Academy and aortic occlusion for patients with suspected intra-abdominal Hemorrhage to reduce bleeding below Okay so my views on this and I probably won't can't go into the physiology indeed but I I think there's a role I mean we know there's a role in trauma surges as a very common procedure in damage control surgery to occlude the aorta um but we do it in patients that are imminently about to arrest okay so this is the patient is starting to Brady or they've you know lost their output you can't imagine the output they are going to fully arrest in the next few minutes and we do the aortic occlusion not so much to stop bleeding distal to it but to generate the coronary perfusion to keep that heart going so it doesn't stop because as I quite clearly showed you if the heart stops and it goes a systolic you're not going to get that patient back so by occluding the aorta for other reasons uh you know that really is effective at um restoring some coronary perfusion um you know secondary uh thing that it does is it might reduce the bleeding below um but anyone who's done any vascular surgery will know that having a clamp on doesn't reduce distal bleeding by much anyway so so yes there is a role for aortic occlusion in abdominal Hemorrhage but it's primarily as a cardiac resuscitation intervention great I think that's okay um thank you all for listening for so long thanks thanks for sharing soon um it was really interesting even though I know nothing about it [Music] um and if you like this webinar our next one is on the 12th of July and it's the realistic challenges of military trauma simulation presented by surgeon with Helen Cardinal S C S Swain um I have no idea what that's going to be about I assume some kind of surgery um if you want your certificates and you're not a member please scan the QR code there it was made and created by the lovely Anna if you can't scan the QR code because you're only fun um just email us at admin and we'll send you across the link to fill in your form but these webinars won't be possible without our great sponsors and one of our sponsors is 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have a good night everybody um be safe and if you're in the rain like I am up here uh make sure you work a goal uh but I will leave you with a little tidbit did you know that the speed of a computer mouse is measured in Mickey's okay that's my educational input have a good night everyone thanks so much [Music]