Trauma Talk Summary: Update Course 2017

So, uh I want to introduce uh Dr. Christian Streck. Uh and uh Chris is uh the the division chief or surgeon-in-chief. Division Chief. Division Chief of Pediatric Surgery at MUSC, Medical University of South Carolina. And uh he has had a fantastic publication on the role of CT scan in blunt abdominal trauma. And we really liked uh his his work and his paper and we uh invited him here uh to really uh give us some information about what we need to know now, how times are changing with uh CT for blunt abdominal trauma. Chris, thanks for for doing this. Sure, thank you and thanks uh for the panel. Um, I feel a little bit Dr. Ponsky set me up here because he let David go first and David presented a really interesting uh case of a hemodynamically unstable patient. And uh I'm going to spend my time talking about the 97% of the patients that we see following blunt trauma that are hemodynamically stable. So it's not quite as glamorous or exciting but these are the patients that typically come into a pediatric trauma center. And I cheated a little bit, I have two cases, but they're from the same vehicle and I wanted to to use them to kind of make the point about who might benefit from a CT and who we can avoid it from. So the first is a six-year-old male, he was a restraint a restrained backseat passenger in a motor vehicle collision. It was reported as a car versus a tree head on at a high speed. Uh he was on the passenger side in the back seat. Uh there was no known loss of consciousness and he presented hemodynamically stable in route. In our center, we have a tiered uh trauma uh activation system. So he was the second highest level. Um on primary survey, he had a patent airway, his respiratory rate was 27. Blood pressure 111 over 81, heart rate 131. On Brozlo, he was about 20 kg and had a GCS of 15. Pertinent physical exam findings, he had some mild midline uh cervical spine tenderness to palpation. And he had a noticeable seat belt contusion, I'll show you a picture of that. Uh his abdomen was fairly soft, a little bit distended, but there were no obvious peritoneal signs. And he had the following uh imaging finding, which is this uh contusion here uh on the abdomen uh consistent with a lap belt uh type of mechanism of injury. The second patient uh was his sister also in the same vehicle. She's uh sorry, I went the wrong direction. She is an 11-year-old female, uh also a restrained back seat passenger in the vehicle. She was found slumped under the front uh driver's seat. There was a reported loss of consciousness. She was hemodynamically stable in route as well. Again a level B activation in the adjacent room. Uh ABC's were pretty unremarkable. She also had some mild midline cervical spine tenderness and she was very distracted. She had several fractured incisors, uh a lip laceration, her midface was stable. And on physical examination, although she was uh very distracted, she seemed to have a normal abdominal exam. She did complain that she had some mild uh abdominal pain. Now, I think I'd like to point out for our audience that that the seat belt side or or the abdominal contusion really should be a red flag for for everyone. So, a lot of surgeons may not see that very often, but it really means that there's a tremendous amount of force that's been generated against the patient uh and so you really need to be vigilant that that child does not have an underlying abdominal injury. Sure. Um and sometimes it's very difficult to assess uh a bowel injury um on CT scan with that. You can assess the abdominal injury, but the bowel injury is difficult to assess. Absolutely. So, I picked these uh two cases because obviously the same mechanism of injury. And I think questions for the panel um really is what is the routine at your center? You know, the goal of a lot of the work we've done is to try to determine what population of patients don't benefit from abdominal CT. So, who who uh do you believe if you will in in getting labs and plain films in the trauma bay, does that depend on activation level? How would you have uh triage this patient? And then ultimately who is responsible at your center for determining what the evaluation is? Is that the ED physician? Is it the surgery resident? Is it the adult trauma surgeon that's at the bedside? Is it the pediatric surgeon? And we've had a lot of discussion about FAST this morning and uh I I share uh a lot of the same biases with the panel and I have some data to share about FAST and our experience, but do any of you use FAST to try to avoid an abdominal CT to try to um find a patient population uh that you feel comfortable not uh scanning. I would like to but I don't. Uh I I don't either. I think the the the problem that we have is that it's not sensitive or specific and, you know, and um yeah. Yeah, I I don't think it ever will be until we get um um IV contrast for it. And you know, once once we have uh one and we actually just got IV contrast for for ultrasound which may make a difference but not not right now. And then how about the the question about labs and plain films? Do you have a routine based on activation level and what is what is your standard routine for for labs and imaging? We certainly have a routine. I can't quote off the top of my head what labs are in each at each level, but labs and X-rays are part of the initial evaluation. So so one of the things that I find interesting is uh we have different tiers of evaluation. The lowest tier is really only evaluated by the ED and we've actually noticed that those patients get more labs. Sure. And sometimes more imaging, which I I don't know if you guys experience the same things in in your institutions that's a great as as well. So, you know, it's interesting cuz I think that we we try to tailor who's going to get imaging cuz we are very sensitive to CT scanning and radiation and everything that goes along with that. The flip side is that I think that in some ways we've gone almost some some almost too far because it's sort of like with the non-operative management, right? You still need to be able to recognize when somebody needs to go to the operating room and you see people hanging on by their fingernails to try like going to the OR is a failure or getting a CT scan is a failure. It can't be seen as a failure. It just need you just need to know which patient it's appropriate in. But we do labs and and we we base our scanning you know, if you have a patient that you can examine and their belly is soft and benign and we we do use the LFTs based on that old study from chop uh and I can never remember which one the AST is supposed to do, which one the ALT is supposed to be if either one's over 200, we scan them. I'm going to clarify that. I know I know you are, I know you are. I did see a head so I'm sort of giving you you a little bit foreshadowing here. Yeah. But uh you know, I I do think that you can still treat the patient clinically, but we do have routines. Okay. So, um a little bit more information about the two patients. So uh we uh rely um a lot on labs and imaging to try to assess some of these hemodynamically stable patients that have a a seemingly reliable physical exam. So the brother with the seat belt contusion hematocrite was 37, white count 21, AST was 49, his lipase was normal. We didn't order a base deficit or lactate and he had a normal chest x-ray. In contrast, the sister uh had an elevated AST, her AST was 222 and she had some small pulmonary contusions on her chest x-ray. So, uh this really gets to the heart of the matter. Who who needs an abdominal CT? We kind of spoke about FAST and I'll give some data on that. And looking at the first patient, is there time or a benefit to imaging a hemodynamically stable patient with abdominal tenderness and a seat belt contusion? Uh looking at the second patient is there any benefit to getting the screening labs to see if this is a patient potentially who could avoid a a CT of the abdomen all together? And then this is not one of the cases I presented, but what about the patient who comes in intubated that has a serious mechanism like a MVC or ATV uh collision, but has a normal physical exam uh on uh on your on your uh evaluation. So, what do you guys think on these two patients or the three examples? Who of these patients would you get an abdominal CT on? I agree with we 100% on the seat belt sign. I have. Abdominal tenderness and a seat belt sign. I would be very, very concerned about that. Yeah. And I'll tell you, you know, the the seat belt sign that you showed is a is a really bad seat belt sign because it's not in the right place. Yeah. Well that's right. That's the key. Yeah, as that's always the question because we sometimes will watch a seat belt sign. If it's over the anterior superior iliac spine in the right place, may just be a you know and you can follow the patient. Because first of all CT scan's not going to be super sensitive for picking up the injuries, although our radiologists I think are pretty good at it, they'll see the focal ilias or something. But I I I I really think that if it's in the wrong place then you're Can you go back to the image and just point out in you know That that image while you're going to find it It's a great image by the way. is why That's what all my kids seat belt sign would look like because every time I look back, they got the lap belt where head is up here and here is the umbilicus, so this is um closer to the costal margin here. Yeah. And you want your seat belt sign over over the bony pelvis. That's what that's the way it's designed. That's why we have booster seats. Sure. Absolutely. Would anybody have gone straight to the OR based on a seat belt contusion alone? No. Okay. So, I'm going to give a little Oh, patients are stable though. Both patients are stable. Right. And as I said, 97% of the patients in our our study that I'm going to mention were normal intensive. So, uh hopefully this will project, but uh this patient, if I can get the pointer to work, there's some uh free fluid that's intermediate density uh along the liver here. This is the posterior wall of the stomach. There's uh fluid in the lesser sac. Maybe a couple dots and free air in the next cut. The duodenum seems to have a hematoma here. Uh and there's some paracolic uh fluid in this gutter as well. This is just another cut of the same uh image showing the same findings. Our radiologist uh interpretation of this, other than what I've mentioned is that this patient in their opinion likely had a posterior gastric uh wall injury. Uh I didn't con agree with this, but certainly uh the findings were uh highly suggestive of uh a uh hollow viscous um injury. Uh and then the second uh patient, uh we did scan based on her elevated AST and um she had a normal abdominal CT. Well, I feel better because I would have scanned both patients. Yeah, what I was going to say. I'm glad you scanned both patients. Okay. All right, so I'm going to present and uh try to keep it to five or six minutes um some of the data that we've put together to help uh drive decision making about abdominal CT. Um, one of the things that's been most successful is we have a group uh the pediatric surgery research collaborative. Several of the uh moderators here um have uh contributed uh faculty members to this uh group. We have 14 institutions uh that have participated uh in the data collection. And uh mostly just want to thank all of them. Obviously, um this is an important topic. Uh there's a lot of pressure I think uh now um in the the trauma uh world uh to get um abdominal CT and this is despite a low incidence of intraabdominal injury, uh less than 12% of the patients have an injury on CT. There's associated costs of course we worry about radiation induced malignancy. Um in contrast um 90% of these patients that are pediatric patients come into a non-pediatric center. And uh standard at most adult trauma centers or non-trauma centers is the pan CT. There's actually a lot of literature out there uh on adult patients that suggests pan CT is safer, there are fewer missed injuries, it's more cost effective. So this is essentially what we're up against as uh pediatric uh providers is uh that the um the the pressure is is in the uh kind of the other direction. There are a lot of studies in the past that have tried to identify some combination of mechanism, history and physical exam findings, labs that might um allow you to identify a population where you don't need to scan the patient. And that was really the goal of our study was to come up with a prediction model uh that was very uh impactful. In 2012, um David mentioned the Pecarn group. They put together a perspective study and um their primary outcome variable were patients with an intraabdominal injury that required an acute intervention. So they wanted to find or identify early patients that needed urgent surgery, that might benefit from angio, that needed a transfusion. They had a criterion of admission for 48 hours for IV fluids to me that's not really an acute intervention, but it is a type of intervention. And they only used history and physical exam findings. This is a bit challenging uh as the providers doing this. There's a lot of subjectivity to just using history and physical exam. We actually uh validated their model and what we found that was that it was actually very, very sensitive for injuries requiring acute intervention, but it missed a lot of clinically relevant injuries. Mostly solid organ injuries like liver and spleen injuries which we felt were important because it it it affects how we manage the patient even if we're not rushing straight to the operating room. So our goal was to come up with a prediction model. Uh we also limited our model to patients that were within six hours of injury that had not had a CT scan prior to transfer. These were patients that didn't have a focal injury to the head. They these were truly blunt abdominal trauma patients. And we did a lot of uh fancy statistics. You can look at uh the paper if you're interested that's in uh Journal of American College of Surgery this year. Uh but we came up with a prediction model. These truly were patients that you would say had a severe mechanism of injury. almost half for motor vehicle collisions at greater than 30 miles an hour, pedestrian or bicycle versus automobile, ATV accidents. And what we found was very consistent with uh prior studies, only about 12% of the patients had an intraabdominal injury and fewer than 3% even when we selected for for more uh likely injured patients had an injury requiring acute intervention. And most impressively, I think was this that the range between the 14 centers of CT scan ordering range from 4% of the population to 96%. Um, so that shows you I think that there's a a great opportunity for improvement in how we decide who needs to scan. Um, these five variables, this is really the take home point I think are um the variables that came out in the prediction model, AST greater than 200, an abnormal uh physical exam, an abnormal chest X-ray in the bay, a patient complaining of abdominal pain or an elevated amaly or lipase. This identified a population that um had a uh 0.6% risk of an intraabdominal injury and a 0% risk of an injury requiring acute intervention. So at least a third of the patients that we're seeing potentially more uh don't need a CT scan even when we select for a more injured population. So negative predictive value was 100% for the injury requiring intervention and 99.4% for all injuries. So does that mean if you had all five of those were negative Correct. as but if you had one of those five, you're not in that group. You're not in the very low risk population. So and I'll show you kind of a breakdown of that. That's an excellent point uh Dr. Holcom. So this is looking at the patients by number of abnormal variables whether they had an injury like a solid organ injury most commonly or an injury requiring intervention most commonly hollow viscous. And as you went up in the number of variables that were abnormal, this is this was the risk of uh an injury or an injury requiring intervention based on the number of positive um uh abnormal variables and those are the confidence uh intervals that were associated with that. So if you had zero of those you there was no patient who had an injury. Do I That required intervention. That required intervention. That's right. And there are only five that had an injury at all. They were mostly uh more minor solid organ injuries. So um to make it a little more clinically practical, we reordered the five variables in the order of information that you obtain as the physician. So the patient complaining of abdominal pain, if it's no or you can't assess based on being intubated or sedated. Uh the next was the physical exam of the abdomen, chest x-ray, AST and abnormal enzymes. You still have the same 34% of the population. But uh if you wanted to look at a group that you might be able to observe uh or uh send home with um careful instructions, uh what we found uh was a low risk uh group um that uh made up 55% of the population with a less than 5% risk of any injury uh and a less than 0.3% risk of an injury requiring acute intervention. One of the uh things that has been criticized about this type of model is people don't feel like they can wait for labs to come back. And I think this would suggest uh that you certainly can wait uh even if it takes an hour to get your AST or your lipase. These are patients that um if stable and have a reliable exam that you can kind of park in the uh pediatric emergency department and wait uh for your labs to come back before you make a decision on abdominal CT and we have certainly sent patients for a head CT sometimes without getting an abdominal CT. So, the challenge from that are two, one is that you occupy the emergency room bay for an hour while you wait for labs and we've done a lot of work to try to minimize the amount of time that patients spend in the trauma bay. Um and then the second is if you send them for a head CT and then the labs come back positive, you have to send them back to the CT scan. True. Our scanner is is immediately next to the ER and we typically move them out of the trauma bay to a like a standard ER room uh to avoid time that up. Um in my opinion, saving the radiation and the cost of the CT is probably worth, you know, an hour of time, uh but I think as was mentioned earlier, it depends on your local resources. Your comfort level, how busy your ED is and But I think sorry to keep jumping in, but the other issue that always comes up is the radiation exposure issue. And I think that um sometimes that's more emotional than it is fact. Sure. You know, we don't know what the risk of malignancy is and. We're going to have that discussion because we have an entire talk about that coming up next. Um, so we'll we'll defer that because I want to go Chris go on and I I want to apologize to the virtual audience because they are lighting up with questions and I and we have not had time to get to them. Sure. I want to not discourage anyone. Please keep putting them because Chris will answer these, David will answer these. Mike, if it's a radiologic, we will answer these questions. I I want to do what we call rapid fire here, not much discussion, just a quick answer. Question is from uh and this is coming from Khaleej Sharif. He says in a patient that has a seat belt injury, they believe you should get oral contrast, it's the only way to rule out a perforation. That's the first question. Quick answer. I would say I I disagree. I agree um that it can be difficult to identify patients with small bowel or colonic injuries. I don't think oral contrast adds to that. Um I I think our CT scans have gotten so good with the multi slice scanners that typically there's evidence uh it may not be free air but there are subtle findings that would make you uh concerned for uh small bowel or other hollow viscous injury. Okay. Uh there's also time I think uh the data has shown that there there's time to uh do serial abdominal exams on patients. Yeah. And uh even if uh it's not clear on the CT, you may uh determine the patient needs further uh evaluation based on on serial exams. Mike, anything to add to that or is that pretty much cover it? I would agree with that. Okay. The thing is though also that a bowel injury although it's an injury is not a life-threatening problem. Correct. Yeah. Okay. And so even if you're unsure on like that scan he showed, if you're unsure if there's an injury, observing them for six hours or 12 hours and reassessing them. There's nothing wrong with that. You don't want to observe them for five days, but observing them for a few hours is a good way to be sure if you will that they need an operation. I real quick. No am I wrong to say this statement. A missed bowel injury a missed bowel injury if caught within 24 hours usually does no increase morbidity. Is that a false statement? There there is a study um through Apsa a few years ago that supports that. Of course, uh I think the flip side of that is we don't want to have delays uh in diagnosis for missed injuries. I think in 2017 particularly in the patient that I showed uh laparoscopy is extremely helpful. Um if there's a moderate even just a moderate amount of free fluid in a male and no um uh hard signs of uh small bowel perforation. Um I I certainly would consider laparoscopy in those patients. I think uh this is a different era than you know, 20 years ago where patients went for DPL or immediately for a a big lapartomy. We're pretty good at laparoscopy now and it's very rare in my opinion that you would miss something doing a laparoscopic exploration. Okay. And then there's uh questions that they're answering for each other. So, I I appreciate you guys all answering each other's questions. Lipase or amalese uh I think the question was asked a while back about if you don't have um if we don't have lipase is amalese good enough? Yep. So, in our study, when we designed it, we um allowed for either. And when it says abnormal pancreatic enzyme, it could be amalese or lipase. In our institution they only do lipases. Most of the places, I shouldn't say most. It was pretty evenly distributed between getting an amalese or lipase. A few institutions got both. There is huge variability in the lab evaluation of these patients and I think that was one of the most impressive findings is that we are all all over the board and how we use labs and which labs we choose to to use to evaluate. Great. All right, sorry to interrupt. Yeah. Um I I just have two slides left and then there's if there's time we could have more discussion, but basically in conclusion, we came up with a prediction model. Uh I think it's um highly practical. Um currently we're validating this. The Pecarn and the nice thing about the Pecarn data set is it's publicly available. We just submitted an abstract that was accepted to East and uh our um negative predictive value of this model in their data set uh for all injuries was um very significant. So, I think uh this uh going forward the challenge will be to get people to implement this and to see if this is better than current uh practice. So that is our goal moving forward.