Pestana’s Surgery Review, Ep. 3 – Trauma

As we begin to look at the vignettes that deal with abdominal trauma, let's remember one more time that trauma could be penetrating or blunt. That on penetrating trauma we typically have to operate to repair the injuries that in blunt trauma we often have to do a lot of diagnostic studies and there is more judgment involved in the management. Let me start by delineating what are the circumstances in abdominal trauma when we have to do a laparotomy, when that is the correct answer. First of all, every gun should wound to the abdomen. The abdomen happens to be just chalk food of structures that shouldn't have holes in them. So every gun should wound to the abdomen. The only correct answer is exploratory laparotomy. That is also the correct answer if we have a stab wound where it's clear that there has been penetration of the abdominal cap. If we have a stab wound where it's all there is a piece of intestine hanging out that all the sun needs to go to the operating room. And finally the third situation where the answer will always be exploratory laparotomy is any abdominal trauma whether penetrating or blunt in which the patient develops an acute abdomen. So we have a situation where it's trauma has occurred in the abdomen and the patient then has abdominal pain, engarding and rebound tenderness. The signs of pertinular rotation, the patient needs an exploratory laparotomy. All right? Well that background let's begin then to look at the specific vignettes. In November 21 and 19 year old gang member is shot in the abdomen with a 38 caliber revolver. The entry wound is in the epigastrum to the left of the midline. The bullet is large and the sauce muscle on the right, he's simultaneously stable, the abdomen is more retent. This is a gonshot wound to the abdomen and the only correct answer is exploratory laparotomy. Now conceivably the question might ask what preparations do we do for that exploratory laparotomy? Now we put an indwelling bladder catheter, we have big bore venous lines for fluid administration. We give it dose of broad spectrum antibiotics but I doubt that those will be the things asked for. I think the choices will be more like should we do CT scan of the abdomen should we do endoscopies or do we do an exploratory lap and the answer is we do an exploratory laparot? Now will they ask you what to do once it on the laparot? Well maybe, I think for the most part you will not but here is one example that I think could be on the exam. Pignette 22. An exploratory laparotomy for the patient described in the previous question, examination shows clean, punched out entrance and exit wounds in the transverse collar. The answer is actually fairly easy. The objective of surgery for conscious wounds of the abdomen is to repair the injuries caused by the bullet. It is not as Western movies might suggest to remove the bullet itself. The bullet is large and the muscles you know the retopartonial area, we do not spend the additional time to dissect the tissues to find it because there is no advantage to the removal of the bullet. Again the objective of the operation is to repair the injuries. I picked the one here with an injury on the colon because for many years I used to be a dog man in surgical circles at every penetrating injury of a colon required a colostum, a diversion with a colostum. And this was true in the war injuries from which this constant derived many years ago. But in the standard civilian kind of injury where the damage to the colon is not as big, a primary repair is in fact possible and it is the prevailing view at the present time. So the answer for the vignette I just read would be we repair, we close those clean, punched out entrance and exit wounds in the transfer scorer. Now I pointed out that every one should wound to the abdomen has to have an extra toilup or anctomy but the question might in fact not tell you this is a one to the abdomen. The question may give you the entrance wound location, the location of the exit wound or where the bullet is lodged by x-rays and let you figure out is that the abdomen? Let's read vignette 23. A 19 year old gang member is shot once with a 38 caliber revolver. The entry wound is in the left mid-clavicle line, two inches below the nipple. The bullet is lodged in the left paraspinal muscles. It is hemodynamically stable but is strong and combative and physical exam is difficult to do. We teach every surgical resident when dealing with a gun should wound to the abdomen, that every gun should wound that is below the nipple line includes the abdomen. This one is there for an abdominal injury. I didn't say and it didn't imply that the chest ends at the nipple line. The chest extends all the way down to the end of the ribcage. The chest and the abdomen are not stacked up like pancakes. They are divided by a dome, the diaphragm. That dome that divides the two then allows for a band of anatomy where there is both chest and abdomen. This gentleman also has a penetrating injury to the chest. He may need a chest tube or something for that reason. But he also has a penetrating gun should wound to the abdomen. So he needs an exploratory laboratory. 24. 42 year old gang is stabbed in the belly by a jealous lover. The wound is lateral to the arm, the lychos on the left. And the momentum can be seen protruding through it. If the momentum is coming out, we know that it is a penetrating injury and therefore an exploratory l upper abdomen is also indicated for this patient. But contrast that to the next one. And the course of a domestic fight, a very edgy old obese woman is attacked with a four inch long switchblade. In addition to several superficial assurations, she was stabbed in the abdomen. She is more dynamically stable and does not have any signs of peritoneal irritation. This is a stab wound and remember the stab wounds to the abdomen give us more leeway in the treatment. There is a little more flexibility here. She is a well-padded lady to begin with or told that she is obese or given the size of the weapon which is not very large and where it all she is completely symptomatic. We have no evidence here of penetration. And so what you would do in this and what the answer would be on the exam is a glove finger in the emergency room is carefully introduced to that wound to see actually to feel if it goes into the peritoneal cavity. Obviously this has to be done very gently. Or else that finger will be the penetrating weapon that gets into the peritoneal cavity. But this digital exploration of the wound in the emergency room determines whether you need further treatment for the concert wound or not. If it is not penetrating, I mean for the stab wound, if it is not penetrating, all we need then is clean it and get those prophylaxis as might be necessary and so on. And exploratory laparotomy will not be needed. Alright, vignette number 26. 31 year old woman smashes her car against the wall. She has multiple injuries including upper and lower extremity fractures, her blood pressure is 75 over 55 for the pulse rate of 110 and a central venous pressure is zero. And we stop here because we already know from our previous review that this lady is bleeding somewhere. Right? She is a trauma victim going into shock with a low central venous pressure. On physical exam she has a tender abdomen with guarding and rebound on all quadrants. We already have identified then an indication for an exploratory laparotomy. And chances are in fact that that's where she is bleeding as well. But because she has a tender abdomen, but guarding and rebound on all quadrants she needs an exploratory laparotomy. The January 27th 31 year old woman smashes her car against the wall. She has multiple injuries including upper and lower extremity fractures. Her blood pressure is 135 over 75 with a pulse rate of 82. This lady is not bleeding. But on physical exam she has a tender abdomen with guarding and rebound on all quadrants and we've already agreed that there's an indication for exploratory laparotomy. And now we come to the ones where we have to do a lot of thinking, being yet number 28. A 26 year old woman has been involved in a car wreck. She has fractures in both upper extremities, facial lacerations and no other obvious injuries. Chestics raise normal. Shortly thereafter she develops hypotension, tachycardia and dropping hematocrit, their CVP is low. Well, let's analyze this. Again, this is a trauma victim who now is going into shock and we're told her CVP is low. So we know this is a lady bleeding somewhere. But the question now is where. So let's review from head to toe where this bleeding could be. We already made a point twice into previous vignettes and we'll make it again. That she cannot be bleeding into the head as the explanation for her going into shock. There isn't enough room in the head to accommodate the liter and a half of life. But she'll be bleeding into the neck she could but it would not go unnoticed. The physical deformity would be obvious. She would look like a toad. There would be this gigantic distortion of an neck if we had that much blood in there. Would she have a liter and a half of blood in the pericardial sac? No. Way before she had that much, she would have developed pericardial tamponad and then her central venous pressure would have been high rather than low. What about a plural cavity? Oh yes. The plural space is big enough to accommodate the liter and a half of blood. But it wouldn't hide from a chest x-ray. And we were told here in the vignette that her chest x-ray was normal. And therefore there cannot be a liter and a half of blood that we don't see on an x-ray of a chest. The arms are too small to accommodate that much blood in a way that would be hidden. And so that leaves three places. The abdomen, a pelvic fracture or femur fracture and the latter would typically have to be comminuted perhaps by that. The lower leg I might add is slightly arms not big enough to hide that much volume of blood. So essentially we're left with a fine. That giving a trauma victim that we suspect is internally bleeding. But the bleeding isn't obvious. The three places where that blood could be accumulating are the abdominal cavity, a pelvic fracture or femur fracture. Now the last two are always looked for in that initial quick assessment of a trauma patient. And that very rapid head-to-toe physical exam that is done in a trauma victim. One of the things we always do is squeeze the pelvis, looking for the pain and the signs of the pelvic is broken. And we look for femur fracture precisely because we know that could be the place for blood to be hiding. If a vignette doesn't say that she has a pelvic fracture, if a vignette doesn't say that she has femur fractures, then obviously the blood is gone. So the only place left is the abdomen. And yet an abdominal surgeon would not do a laparotomy without prior confirmation that yes that's where the blood is. So the next step on this patient is to verify that there is intra-dominal bleeding. Now how do we do that? Let me give you a little historical perspective because there are now at least three different tests we can do and we need to put them in perspective. For many many many years, the reliable way to make this diagnosis was to do a diagnostic parotoninial lavage. An invasive little procedure, or we made a little caught in the abdominal wall, needed a little local anesthetic there. And introduced into the parotoninial cavity, a catheter through which we infuse the liter of fluid, typically saline, slosh around the patient a little bit and then retrieve the fluid in a siphon-like manner to look at it. Of course if the fluid was bloody, it meant there was blood there, the fluid was clear, it meant there wasn't. And we even developed fine or criteria, doing red cell count to determine the small amount of bleeding versus the large amount of bleeding and so on. The parotoninial lavage, even though as I said, was a very useful thing for use for many years. Had a couple of shortcomings. One you see it was an invasive procedure. We had to put a little caught in the belly of the volume, put a catheter in. But it also had a shortcoming that it only gave a yes or no, yes there is a blood, another is no blood. It didn't say where was a blood coming from. And it didn't allow us to speculate, is this bleeding in consequential, is this a kind of bleeding that will go away if we just wait or is this an organ that is smashed that we have to intervene. So it used to be that we operated every patient that had a positive diagnosis to parotoninial lavage, only to find many who had a trivial injury for which actually no repair was needed. And then we got a far better diagnostic tool, the CT scan. The CT scan of the abdomen is an excellent way to detect the presence of blood. Not only that, it also shows us the injury from which the blood is coming. So we can see the lacerated spleen. We can see the laceration in the liver. We can get an idea how bad that the injury is. Is it going to require surgical repair? Is it likely to stop bleeding on the zone? And I might add, obviously the CT scan is a non-invasive test. But the CT scan has a little problem. At the present time, in most settings in the US away, a patient who is in the emergency room who needs a CT scan has to leave the emergency room to go to the X-ray department to get a CT scan. Now that's fine in most circumstances. But if a patient is literally hovering between life and death, if a patient is in shock, not responding to associated efforts, literally crashing as we say. That patient cannot leave the environment of the emergency room where all the associated efforts can be made to take a trip to go to another area of a hospital to get a CT scan. So it has always been given as the precondition for a use in the CT scan in Blondtabdominal trauma that the patient must be hemodynamically stable. Let me as an aside point out that this may be changing in the future. The same way that 50 years ago, all emergency rooms in the country began to get their own X-ray machines. After one, you had a patient in the emergency department with a broken bone, they didn't have to go to the X-ray for that particular X-ray. There is now a situation where CT scanners are beginning to be placed right in the emergency department. So someday in the future, we may not have this limitation anymore. But at the present time, that is a requirement. But there is yet a third way to make this diagnosis. CT scan has also given us small, portable sonogram machines that the patients can have done in the emergency room. This is not a sonogram to be done in the X-ray department. It doesn't require a trip away from the ER. These are little sonogram machines that are used by the trauma team. They have been trained to use them and they can in a non-invasive way. They are by the same yes or no answer that we used to get from the peritoneal of us. Any many, many institutions in the country, this sonogram that can be done in the ER has already displays render obsolete the diagnostic peritoneal of us. So let me recapitulate that. As we go back to this vignette, where we have a lady who's sustained trauma, she's going into shock or CVP is low and we have no evidence or blood anywhere else and we are left with a gas that it has to be an abdomen. If you read this vignette again now, you would find more detail in it. it. Not examination question. The examination question would have to make it clear to you whether the patient is chemodynamically unstable, needing resuscitated efforts to continue, in which case your answer will be either diagnostic peritoneal of ash or sonogram dung in the year, or it may make it obvious to you that as soon as intravenous fluids were giving, as soon as the ringer's lactate was used in resuscitation, the blood pressure came up, it's being stable, the patient is doing fine in which case, you know, then the way to make the diagnosis is the diagnosis is the city scan. And I might add, if that city scan shows it's trivial injury, and by then this chemodynamically stable condition remains stable, the patient may in fact never need an operation. All right, let's look at other variations on this theme. In January 29th, a 27-year-old intoxicated man smashes his car against a tree, he's stender over the left lower chest wall, chest x-rays shows fractures of the eighth, ninth, and tenth ribs on the left, he has a blood pressure of 85 over 68, and a pulse rate of 128. Again, a trauma victim with a low blood pressure of fast pulse rate were not told that he's got big, distended veins, so he must be bleeding somewhere. And we have here, in fact, an indication of specifically where. Let me give me backtrack for a second to set up a stage that gives us a clue here. When we did the exploratory laparotomy for patients that had sustained long trauma, had a positive peritoneal avas, where in shock, etc. We always found that the most common injury was a ruptured spleen. Actually, now that we're doing city scans on patients of long-term trauma, and we identify the ones that are bleeding minimally and do not require an intervention, we find that more commonly, in fact, the liver is the source of intra-dominal bleeding. But if you look only at the sub-sertifications that have intra-dominal bleeding and are bleeding substantially are going into shock, ruptured spleen is the most common reason. Well, here is the question that already points in that direction. Left lower ribs that are fractured, the patient that is going into shock. If you had to match this one in an extended matching set, this is a ruptured spleen. Well, let's pull through this one a little further. In the number three, begins the same way. 27 year old intoxicated man, as matches his car against the tree, his tender of the left lower chest wall, chest x-rays shows fractures of the eight, ninth and tenth ribs on the left. He has a blood pressure of 85 over 68 and a pulse rate of 128, which do not respond satisfactorily to fluid and blood administration. That's already telling you this is not a good candidate to go get a city scan done. So the only options here that are not diagnostic peritoneal labas or the sonogram done in the year. Where we keep reading, he has a positive peritoneal of us and that exploratory laparotomy ruptured spleen is found. So now the question is what do we do next? Let me reassure you first of all that they will not ask you in the US, Emily, how do you do a spleenctomy? Remember this is an examination for fourth year medical students, not for fourth year surgical residents. But you will be expected to know what will the surgeons attempt to do or prefer to do under the circumstances and the answer here is they will do everything possible to repair rather than remove the spleen. And at one time until not too long ago we almost behaved as if the spleen were disposable and we took them out whenever they had been damaged by trauma. There is now recognition that the spleen is important for immunological function particularly in children. This may not be so critical in the adult but particularly in children. But at any rate the answer now if you are asked you have found that exploratory laparotomy ruptured spleen, what would be the preferred thing to do? It would be to repair rather than remove the spleen. However if the question tells you we couldn't repair it, it had to be removed and incidentally that would happen in two circumstances. One might be it is shattered beyond any physical possibility to put it together again. And the second possibility it would be could actually be a salvageable spleen but the patient has so many other critical life threatening injuries. At the time that it would take to repair the spleen simply cannot be devoted to that purpose because there is so much more that needs to be done in the lab living and in that case a quick splenectomy may be the answer. If you put it to that position, a splenectomy had to be done. Then you were expected to know that the patient now has to be immunized against those encapsulated bacteria that could lead to culminating sepsis in the future. That means the patient will need administration of pneumovax for pneumococcus. But also nowadays we immunize them for amorphilose influenza and for meningococcus. All right. Now we're going to move on to other features of management of abdominal trauma. And your number 31. A multiple trauma patient is receiving massive blood transfusions as the surgeons are attempting to repair many intrapdominal injuries. It is then noted that blood is oozing from all dissected raw surfaces as well as from his IV line sites. His score temperature is normal. So we are told this is a patient who's developed the coagulopathy in the middle of the is already prolonged operation where a lot of blood has been given. This is in fact pretty predictable. When a patient gets more than 10 or 12 units of blood, a coagulopathy is going to ensure. Now it would be ideal from a purely scientific viewpoint to find out exactly what's wrong with the coagulage and do a bunch of laboratory studies to determining exactly what is at the patient need. But under the circumstances described here, there isn't time to do that. The patient is already oozing. We're told that his core temperature is normal, but if we keep that belly open much longer, it may no longer be. And so we essentially have to use a shotgun approach. And these patients are given fresh frozen plasma and platelet pipes. So this empiric approach is justified under the circumstances. Now the next thing you add has the same beginning, but it has a little additional thing. During the course of an upper auto-before-multiple trauma, the patient develops a significant coagulopathy. A core temperature below 34 degrees centigrade and refractory acidosis. The problem is no longer confined to coagulation. There is now also hypothermia and subsequent that there is acidosis. This operation needs to be stopped immediately. Now this patient will be given the platelet packs and the fresh frozen plasma, but also packing will be done for all the areas that are bleeding and the abdominal wall put together in a temporary function with towel clips or maybe with a plastic draped that is staple to it. Because if that abdomen continues to be open, the hypothermia will kill the patient. The patient then needs to be rewarned and once he has been rewarned and the coagulopathy has been treated, we will then continue that operation that had to be interrupted at this time. All right, let's look at another situation we see in big, long-standing, complicated, difficult operations for multiple abdominal trauma. Incidentally, this couple of next vignettes that we're going to review, these are things that happen in the kind of patient that up until not too long ago would have died on the operating table. Surgeons who practice trauma surgery 10 or 20 years ago never saw the kind of vignette we're going to read now, but now that we're getting better all the time with anesthetics, support, with blood transfusions, etc. These patients are sure of even to develop new entities. Here is one. An exploratory laparato for multiple intra-dominal injuries has lasted three and a half hours. During which time multiple blood transfusions have been given, and several liters of rings like they have been infused. When the surgeons are ready to close the abdomen, they find that the abdominal wall edges cannot be pulled together without undue tension. Both the belly wall and abdominal contents seem to be swollen. This new entity, which we now call the abdominal compartment, syndrome is essential at the price that has been paid for survival. It has required enormous amount of blood and fluids to maintain the patient alive. A lot of that fluid has ended up into the tissues, and now we literally cannot close the belly wall. Actually, we could. We could if we pulled and did it. But that would not be a good idea. If we did that, the patient would be unable to breathe. The patient would not be perfused, the kidneys are properly, and we're going to renal failure. So what we have to do in this situation is we have to close the abdomen in a temporary way that doesn't approximate the edges of the tissue. Obviously, we cannot leave the abdomen open either. That would lead to hypothermia and the abdominal contents would get contaminated. So what we do here is we do a temporary closure. We take a piece of plastic or a mesh of some kind, which we typically staple all around the abdominal opening. So now the contents are protected. The patient isn't going to develop hypothermia. The belly isn't going to be contaminated, but those abdominal edges didn't have to be pulled together. And then later, a week later, whenever we can do it, we should be able then to either pull together the edges of abdominal wall or if by then everything is kind of, you know, healing the way it is, we sometimes put skin grafts on top of the mesh that had been placed originally and then at an even later date, prepare the ventral hernia that has been produced. Now, sometimes this abdominal compartment syndrome isn't obvious at the time of closure. Let me read the next one yet. In the first post-operative day, a trauma patient develops a very tense and distended abdomen and the retention sutures are cutting through the abdominal wall. He also develops hypoxia and greener fate. Well, the abdominal compartment syndrome wasn't obvious when the operation was ended. The edges were able to be approximated, but now, for a few hours of fast, the swelling is there. The patient is not making a urine, cannot breathe. The patient needs to go back to the operating room. We have to open that abdomen, give it room, and again, use a temporary closure with a plastic sheet or with the mesh. All right. Now we're going to move on to pelvic fractures. Let me summarize the saline points first. Pelvic fractures may give us a side-to-belidian responsible for shock. Or, pelvic fractures may give us injuries of nearby organs. And those are the two items that we need to identify in the questions. That's we've been yet on the 35. In a rollover car accident, a 42-year-old woman is thrown out of a car and subsequently the car lands on her and crosses her. At evaluation in the ER, it is determined that she has a pelvic fracture. Remember I mentioned before, in that quick initial survey of a trauma patient will always look for pelvic fracture. She arrived high-potensive, but responded promptly to fluid administration. City scan shows no intra-dominal bleeding and a pelvic hematoma. All right. So the two features that could be parod of the issues raised by pelvic fractures she doesn't have the problem of bleeding. And that's fortunate because I would have been a difficult one to handle. We've been told now that the fluids have been given and she's now stable. We're told there is a pelvic hematoma. Well, let me dispose of that one very quickly for you. We leave it alone. The best policy for pelvic hematomas that are not expanding and apparently causing no problem is not to bother them anyway. We were to pick the answer in the questions as let's operate and open that hematoma it would be a prescription for disaster. So the only issue I left here with is when ever there is a pelvic fracture, nearby viscera may be injured at the same time. On patients of either gender, the rectum and the uniblator are at risk and they need to be evaluated. In women we also need to evaluate the vagina but not the urethra because the urethra is very small and the female typically in the ranger in the male on the other hand will also have to evaluate the urethra. So the answer is on this and here, revolve around the need to do a proctoscopic exam to do in this case a pelvic exam and perhaps to put dye into the urinary bladder or put a catheter into the bladder and see there is blood in there first because we need to rule out rectal injuries, vaginal injuries and bladder injuries in this lady. If it had been a male it would have been urethra injuries. I'm not going to spend time on that now because just coming next we have in fact the urological injuries. Let me move to the next one. It's now been yet 36 in a roll over car accident. A 42 year old woman is strong out of her car and subsequently the car lands on her and crushes her. At evaluation in the ER it is determined by physical exam that she has a pelvic fracture. She arrived hypotensive and did not respond to fluid resuscitation. Hemodynamic parameters have continued to deteriorate. Sonogram don't at the ER shows no intraptominal bleeding. Well she's not bleeding in the abdomen, she's bleeding somewhere, she's got that pelvic fracture, that's what she's bleeding. Unfortunately we don't have a good answer for management. I have no trouble identifying for you the source of bleeding here. But what do we do to stop that bleeding? It's not easy. Here's another example of where in spite of our gigantic egos and our conviction that we can fix all the problems by operating here we can't. If we operate this lady the operative side will not be where the bleeding is, the bleeding is deep into the pelvis. They will not be little vessels that we can clamp. It's coming from the plexus of veins in front of it. You know pelvic bones, we don't do well when we operate for pelvic bleeding so we prefer not to do it. Our telegraphic approach could work if the bleeding were to be from arteries. They could be embolized but often it is from veins. Probably the only answer that I would suggest you might find on the exam that a lot of people would say that would be the thing to do is to do external fixation of the pelvis. You know pins to be driven into the bones on either side of the fractures and then connected to one of those skeletons of metal outside the patient that create the framework that prevents those fragments from moving. Because in that way at the least we don't have additional bleeding caused by moving fragments of bone and bone. All right. Well let's move on as I indicated a minute ago to urological injuries. Now for purposes of the exam the hallmark of urological injury will be a trauma patient who has blood in the ear. Now that blood in the urine could be coming from the kidneys, to be coming from the bladder and in the case of a male it could be coming from the uetra. I pointed out already that the female uetra by virtue of its very small size is sort of protected from that kind of injury. The first hint as to where is the source of the bleeding will be from the additional injuries the patient has. So if we're giving a trauma victim blood in the urine and if it is blunt trauma they are broken ribs but no fracture pelvis. We should be thinking of the kidney as a source. For a given blunt trauma blood in the urine and the pelvic fracture. We should be thinking of a bladder on either gender or additionally the uetra in the male. And if it is a penetrating injury then again the location of the entry wound we'd either suggest the kidneys or suggest the bladder. Well let's begin reading the answer. The young male is shot, point blank and the lower abdomen. in just above the pubes. He has blood in the urine and no evidence of rectal injury. Well, if the entry wound on this Gonshot wound is right above the pubes and there is now blood in the urine, that's obviously not coming from the kidneys, that's coming from the bladder, that's what's right above the pubes. And incidentally, the answer for this young man will be an explorer, Doriela Barotum. Remember, we pointed not too long ago, that Vringon should wound to the abdomen, needs an explorer, Doriela Barotum. This one does too. The N-38, a woman is shot in the flank. And when a folic athlete was inserted in the ER, the urine was found to be grossly bloody. One of the entrance wounds is in the flank and she now has blood in the urine. The kidneys, the obvious source. And I might point out at this time, most penetrating injuries of the kidney that lead to hematuria, like this one, particularly Gonshot wounds end up with surgery to repair. So again, the answer for both of these vignettes will be the appropriate operation to repair the injuries that lead to the blood in the urine in the first place. Now let's talk about blood trauma though, because that will, as usual, give us more challenges. The N-39. A 22-year-old male involved in a high-speed automobile collision as multiple injuries, including a pelvic fracture. On physical exam, there is blood at the meagres. So here we have the trauma victim with a pelvic fracture and blood in the urine. We know the source is either bladder or an amel, bladder or ulythra. In this particular case, we already can see the blood at the meagres. So what we do next is absolutely clear-cut. We do a retrograde ulythrogram. We do not, let me emphasize this, we do not put a folic catheter. Because he already has evidence of potentially ulythral injury, if he has a ulythral injury and we put a folic catheter, we may make that injury worse than it was. So we first inject radiopeid dye. That's a retrograde ulythrogram and get pitched. Now you may be giving a question on the exam where the injury to ulythra is absolutely clear-cut. I want to read you a couple more that give you the entire constellation of findings. The end number 40. A 19-year-old male is involved in a severe automobile accident. Among many other injuries, he has a pelvic fracture. He has a blood admiators, scrotal hematoma, the sensation that he wants to urinate but cannot. Crectal exam shows a high-riding prostate. If you were given this one in a multiple match-in-set and you were asked, "What do you think is the injury?" The injury is ulythral, in fact, is posterior ulythra. Because you have all those other findings of the sensation of wanting to urinate, the inability to do it. Directly some cannot find the prostate because it's now gone up. But really, in terms of the management, before you read all the other details, the instant you read that this young man with a pelvic fracture have blood admiators. You already knew. The story to do is a retrograde ulythrogram. The end number 41, same thing. A 19-year-old male is involved in a motorcycle accident. He has blood admiators and a scrotal hematoma. Again, blood admiators is already sufficient. You also have a scrotal hematoma. You have a ulythral injury. In this particular case, if you need, it continues to say retrograde ulythrogram shows an anterior ulythral injury. There's a minor detail here that I don't think the last you. But urologists frequently prefer to defer the repair of a posterior ulythral injury, while on the other hand, they typically do an immediate repair of an anterior ulythral injury. All right. Let's move on. The end number 42. A 22-year-old male, involving a high-speed on a real collision as multiple injuries, including a pelvic fracture. At the initial physical exam, no blood is seen admiators. In search of a folic catheter, he's attempted, but resistance is met. If you're given this vignette, the answering immediately would be removed that folic catheter. Do not continue to attempt to put it in, because chances are the reason is not going in is because there is, in fact, a ulythral injury, even though it was an advertised by blood admiators. And so you need to do a retrograde ulythral ram. Now, being in number 43, 22-year-old male, involving a high-speed on a real collision as multiple injuries, including a pelvic fracture. I think we're making the association now, I hope, that a pelvic fracture is a potential cause for bladder or ulythral injuries. A folic catheter is easily inserted. And it shows that there is gross hematuria. Well, we're now past the ulythral. There is a pelvic fracture and there is gross hematuria and it wassing coming from the ulythral, and it's coming from the bladder. In fact, the other version of this vignette might have been a lady, rather than a man. If it is a lady, then it has a blonde trauma, the pelvic fracture, end the blood in the urine, we know that in the female, the ulythral is not the likely side, the likely side is a bladder. Well, in either of these two, if we now have reason to believe this blood is coming from the bladder, the thing to do then is a retrograde cis-togram. We now inject the dye through the folic catheter, feel the bladder with dye and take pictures, but we don't stop there. We then empty the bladder and take pictures again. Let me repeat that. When we're looking for bladder injury, in that patient had the blonde trauma and the pelvic fracture. If the injury were to be at the dome of the bladder, when we feel the bladder with dye, the dye will extravase, we'll see it in the picture. But more often than not, the injuries to the bladder in this blonde trauma, pelvic fracture situation, are at the base, near the trigo, and there the extravassation of dye may be posterior extraperitoneal behind the bladder. And therefore, the dye that has extravassated is actually not seen because it is occluded, because it is interfear with the dye that's in the bladder itself. So that's why that second picture is needed. The bladder is emptied and the next race taken again to identify that kind of a bleak. All right, we're in number 44. The patient involved in a high-speed automobile collision as multiple injuries, including rape fractures and abdominal conditions, but no pelvic fracture. In search of a folic after the shows that there is gross hematuria and pretocrate cystogram is normal. In fact, we already knew even before we were told that the retrograde cystogram was normal, but the source of the bleeding here was likely to be from the kidneys, right? This was a blonde injury that rather than producing a pelvic fracture produced rib fractures and abdominal contusion. This is higher up. And the thing to do here is a CT scan. Most blonde trauma to the kidney that results in hematuria does not require surgical repair. The judgment as to whether it will require a nod can be done by the experts and they base that in part on the CT scan findings. I don't think you'll be asked to make that determination, but you should know that when we find hematuria in a blonde trauma patient who rather than having a pelvic fracture has higher up injuries like pre-practures that what we do next is a CT scan looking for the renal injuries that we expect the patient will have. I mean, in 45 percent the situation that in fact quite rare, it would almost qualify astrivia as a bizarre thing that should not be on the exam. But I mean, I pointed out to you earlier that if a clinical situation provides a good example of anatomy or physiology and so on, been reflected on a clinical setting, it's a reasonable thing to be on your side. Let me read it. The patient involved in a high-speed automobile collision as multiple injuries, including rip fractures and abdominal conditions. In session of a folic catheter, shows that there is hematuria and retrograde cystogram is normal. City scan shows renal injuries that do not require surgery, which remember is the majority of them. Six weeks later, the patients develop, it develops acute shortness of breath and the flank gruey. What has happened? Well, there's a sort of a situation that we see in several places in the body. Whatever we have, a big artery and a big vein that go together, renal artery and renal vein, being a good example. And there is an injury to those vessels that is not defined further and not treated at the time. It is possible eventually to develop an arteriovenous fistula. Well, here we have the patient hand, greenery or known to us. There was an injury to the pericle, to the artery and the vein. Nothing happened at the time, but shortly thereafter, AV fistula forms. As you know, that can overload the circulation very quickly, can lead to heart failure. And then, of course, a bruey is hard. So this is how we can reconstruct this one. If we do an arteriogram, it would show the AV connection and then it would have to be repaired. You know, another version of this kind of thing might be the blonde trowem at the renal injury, nothing needed to be done at the time. And then we're told a few months later, the patient becomes hyperattensive. In which case, of course, the mechanisms would be, there is this schemia of a part of a kidney, there is stenosis of a renal artery of one of the renal vessels. All right. The next two vignettes have to do with what do we do? That the trauma patient doesn't immediately show hematuria, but does so as a later date. Vignia number 46. A 35-year-old male is about to be discharged from the hospital, where he was under observation for multiple blonde trowem sustained in a car wreck. It is then discovered that he has microscopic hematuria. Vignia number 47, a four-year-old falls off his tricycle in the ensuing evaluation is found to have microscopic hematuria. Both were told microscopic hematuria, both subsequent to trauma. We might think, well, they're both in consequential things. Well, actually, it's in consequential in the adult. It is not in consequential in the child. So these two vignettes, the one that says the 35-year-old was in the hospital for a few days, as he's ready to leave, we realize there's micro hematuria, but he had big trauma that justifies the fact that he now has a trace of blood in the urine. We leave it alone. Nothing is needed for that patient. But on the other hand, in the pediatric age group, and particularly, if the magnitude of the trauma doesn't justify having hematuria, you know, this little kid fell off his tricycle. That's not big trauma. That hematuria may in fact be the first sign that alerts us to the fact that the child has a congenital anomaly over the urine extract. And so, whereas the first of these two doesn't need anything done, the little kid needs a urologic adevaluation. I'm going to leave it at that now. In subsequent vignettes, we will have a whole chapter devoted to urology, and we will talk about what is a urologic adevaluation at that time. All right, vignette number 48, a 14-year-old boy slides down a banister, not realizing that there is a big knob at the end of it. His mash is a scrotum and comes to the ER, with a scrotal hematoma, the size of a grapefruit. And probably I should add, I should have written into this vignette, he's urinating okay, and there is no blood in the urine. So you don't have to be thinking about a urology. All you have is a scrotal hematoma from direct blonde trauma to the scrotal contents. This could have been a kid that was kicked in the growing street fight. Now a big scrotal hematoma, the fact that it's a big hematoma doesn't really mean very much diagnostically, because as you know, the tissues in the scrotum are so lagged, we don't have big, fascial barriers there to contain bleeding. It's very easy to develop a big hematoma. The question is, is the testicle fracture or not? We can answer that with a sonogram. So the answer for the question is, is it needs a sonogram? If it's testicle is fracture in two pieces, needs to be repaired, if not, it can be left alone. And the last of urological injuries is one that sometimes when we talk about it, people think it's kind of a funny humorous thing. But obviously it's not to the person to whom it happens. And yet it's one where we need a high level of suspicion. I think this will be clear as I go into the minute. The end of the 49. A 41 year old male presends to the reporting that he slipped in the shower and injured his penis. Exam reveals a large penile shaft hematoma with normal appearing glands. This is more than what it appears to be. A big hematoma in the middle of the penis with the normal glands and one sign, normal shaft on the other. This in fact is a fracture of the tunical budgina, a fracture of a corporecavernosa. I guess what is also called a fracture of the penis. It didn't happen the way the patient said. These things happen typically during intercourse, typically highly imaginative, very acrobatic, woman on top, and there is trauma to the penis that breaks the penis. But the patient is too embarrassed to give all the details on how it happened. So the cover story is part of a presentation. The toilet lid fell on him or something. That kind of thing. But people who deal with this kind of situation in the year have to be able to read beyond the cover story and recognize that this in fact is an injured, that probably occurred when the penis was erect and is actually a fracture. And it needs to be repaired. And it's in fact a urological emergency. So it's important to recognize it because prolonged surgical repair is indicated. All right, we move now to the extremities. As far as penetrating trauma to the extremities is concerned, the main issue is whether major vascular structures are involved or not. So the questions that we might find on the exam of gonshot wounds or stab wounds to the arms or to the legs, that's what we're going to have to see. Are big vessels damaged or not? Well, let's begin reading minutes. We need number one. The 25 year old man is shot with a 22 caliber revolver. The entrance wound is in the anterior lateral aspect of his thigh and the bullet is seen by X-rays to be embedded in the muscles, posterior lateral to the femur. Let me read again the landmarks here. Entrance wound anterior and lateral in the thigh, the bullet posterior and lateral to the femur. We know from our knowledge of anatomy that the femural heart and the femural vein don't travel in the lateral aspect of the thigh. They are in the anterior medial. So anatomy alone tells you you cannot have a major vascular injury in this case. This man doesn't need arterograms. This man doesn't need exploratory surgery. This man needs a wound to be clean. Needs whatever appropriate tetanus profilaxis might be required. And this will depend on how recently he was immunized. But he's had an injury that requires that we think about tetanus profilaxis. And that's it. And as I pointed out earlier, I proposed the abdominal wounds. We can leave that bullet there. Bullets have to be removed only if they are near a vital structure and what a fracture is going to do further damage. So when a bullet is next to the spinal cord or next to the arch of aorta, things like that, we remove those bullets. But this one can be left there. Now, there is a pitpein number two. 25-year-old man is shot with 22 caliber revolver. The entrance wound is the anterior medial. It's in the anterior medial aspect with upper thigh. And the exit wound is in the postural lateral aspect of the thigh. He has normal pulses in the leg. No hematoma on the entrance side. Extrace sure the femur to be intact. You say, well, it sounds like it's fine. He doesn't have a hematoma. The pulses are OK. And I told me here, tell you. because the trajectory of this bullet is near the federal archery and vein because the entrance wound is in the anterior medial aspect of the upper thigh. And in fact at one time until not too long ago, every injury like this one would have gone to the operating room for an exploratory operation. Atendency nowadays in the manager to trauma has been to be a lot more conservative than it was a case 10 or 20 years ago. And so this patient today would probably get only an anterium ram but he's going to need that anterium ram. We cannot simply assume from the fact that he's got pulses that he doesn't have an injury to his vessel. He could have an injury that is not obvious. But the decision could be even easier. That's great being in number three. 25 year old man is shot with a 22 back caliber revolver. The entrance wound is in the anterior medial aspect of his upper thigh. The exit wound is in the posterior lateral aspect of the thigh. He has a large expanding hematoma in the upper inner thigh, the wound is in thigh. That large expanding hematoma can only be coming from those big major vessels that we know from our knowledge of anatomy are in the trajectory of the path of the bullet. So this gentleman needs surgical exploration. We're going to operate, we're going to gain proximal and distal control and then repair the vessels that are injured. Incidentally we don't need an archaeogram ahead of time. Anterogram ahead of time is needed only when it would dictate what specific surgical approach we use. Remember we pointed out the base of an egg as an example of that. And here the approach would be the same. Okay. Number four. A young man is shot through the arm with a 38 caliber revolver. The path of the bullet goes right across the extremity from medial to lateral sides. He has a large hematoma in the inner aspect of the arm, no distal pulses, radial nerve policy and a shot of humors were giving in fact a whole bunch of injuries, all of which are going to need some attention. But the question here, the important issue of this one will be which of these injuries are we going to repair first. I don't mean today to more next week. I mean which one gets done first and which one follows and which one follows. My purely biological viewpoint, the greatest urgency is posed by the vascular injury. The longer that extremities without blood supply, the more problems we're going to have. But from a practical viewpoint, a vascular repair is a very fine piece of technical work, one with magnifying, you know, operating microscope with a very fine suture. And once it is done, it should not be destructed in any way. Put them together a shattered bone on the other hand requires more violent maneuvers, a shattered bone to be put together, to be screwed in place, to put plates to be placed. There is gross motion that is required. So if we were to do the vascular repair first and do the bone repair, the bone repair might destroy the vascular repair. So by necessity, we have to do the bone repair first. Once we have a stable extremity, there isn't going to be moving anymore, we do the vascular repair. The last thing is an air repair. In fact, an air repair could even be deferred for another. Fine. But there is a little extra detail. And this is a topic we are going to cover repeatedly in the rest of the surgical review. The forearm and the lower leg are the two locations in the body, most likely to be the side of a compartment syndrome. A compartment syndrome is potentially a very devastating injury that may kill the muscles on that area of the body and result in permanent disability. We're always as surgeons on the lookout for the compartment syndrome. One of the things we know can produce a compartment syndrome is prolonged ischemia, eventually followed by reperfusion. Once the reperfusion gets to the damaged tissues that were ischemic a long time, swelling, well ensue, and if it isn't a closed, facial compartment situation like we find in the forearm of the lower leg, the compartment syndrome could develop. In this case, the delay that was imposed by the necessity to begin with a bone repair to then make it advisable that one's a vascular repair is done that then fasciotomies be also adding fasciotomies should be the last part of his operation. Alright, in your number five, in a hunting accident a young man is shot in the leg with a high power big game hunting rifle. He has an entrance wound in the upper outer thigh that is one cm in diameter and an exit wound in the posterior medial aspect of the thigh that is eight cm in diameter, the femur is shattered. This little vignette introduces us to a little quick review of wound ballistics. The damage done to human tissue by a bullet going through is directly proportional to the mass of the bullet, so the bigger the bullet the more damage. But it's also directly proportional to the square of a velocity, not to the velocity, but to the square of a velocity, so that as bullets travel faster, the damage they inflict on the tissues multiplies tremendously. We frequent a classify firearms into two groups, law velocity and high velocity. The gonciot wounds that we see from weapons at fire at less than 1500 feet per second are typically referred to as law velocity injuries. And they are essentially the injuries limited to the path of the bullet. But on the other hand, weapons at fire at 3000 feet per second or more, those are high velocity injuries. And those have so much energy that is then dispersed into the tissues, they create an enormous cone of destruction. It is a cone like this vignette points out. The entry one isn't really that big, but the exit wound is gigantic. There's a perhaps little generalization here, but sufficient for our purposes. Most civilian weapons are law velocity. So the injuries we see with people shooting each other over the weekend or even the injuries we see when the police is involved. Those weapons are law velocity weapons. On the other hand, military rifles, AK47, M16, or the kind of hunting rifles needed to kill an elephant or a rhino, not the hunting that you need for deer. But the kind of weapons needed for big game hunting are also high velocity weapons. Those produce horrible destruction. So in this particular vignette, tall that he was a high-powered big game hunting rifle. This young man is going to need at the very least, very wide, the breedment, actually probably more likely on amputation. Okay. Vignette number six. A six-year-old girl has a hand forearm and lower part of the arm, caught in the ringers of an old fast-shin washing machine. The entire upper extremity looks bruised and battered. All the pulses are normal and the bones are not broken. This is a crushing injury. You know, this could have been a girl falls under a boss and the wheels of a boss run over her leg or something like that, a crushing injury. There are two concerns. One is a myoglobinemia, myoglobinuria issue. All that muscle that has been crushed is going to free up myoglobin, first into the blood, then from the blood into the kidneys and this could lead to green of hay. So part of a management of his little lady is monitoring of hemoglobinemia, monitoring for hemoglobinuria and if present a lot of intravenous fluids, osmotic diuretic, like manitol, alkaline station of a urine to protect against this. I might add the same way that my loving comes out, potassium comes out of crush. muscle cells as well. It might not be a bad idea also in this little girl to monitor levels of serum potassium. But the other issue on related to what is dumped into the blood is the damage that was done by those muscles may then lead to those muscles swelling. This is a forearm where those facial compartments that don't allow the swelling to occur. This is again a situation that could lead to the compartments syndrome. So a fasciotomy may again be part of a management needed here. All right, we're going to now change topic and move on to the issue of burns. Most of the vignettes related to burns will have to do with pheromol burns heat, but there are a couple of vignettes here dealing with the other types of burns, chemical and electrical. So let's go into those first. I mean, introduce the first of the vignettes here which has to do with a chemical burn. The same way that I introduced this topic to the medical students at the school where I have worked for many years. When I lecture to our medical students on chemical burns, a way I describe for them the essence of a chemical burn, is a chemical burn is the gift that keeps on giving. And by that, that being as long as the chemical agent is still there, the burn will continue to happen. And therefore, the most important item in the treatment of a chemical burn is that massive irrigation we do to eliminate the chemical agent from the patient. And the sooner we do it, the better. Let me add one or two more things. The chemical burns, as you know, could be acid or alkaline. The alkaline burns up into be wears and acid, but the management is similar about it. The acid that is most frequently available to people to be injured with is a battery acid in the car. And the alkaline substance is more easily available. And there are those drain on cloggers that are found under the sink, the liquid plumber, the drain, those are very strong corrosive alkaline. So the vignette will typically say that either the battery from the acid from the battery car or from the alkaline from the sink, you know, other ones that produce injury. Before I go into the vignette, though, let me do one more little thing. As you go into one of these questions, please, please, resist the temptation to play chemist as a way to solve the problem. The patient was burned with an acid should not then be bathed in an alkaline or vice versa. There's only one exception to that and will come to it soon enough. Let's go vignette number seven. You get a phone call from a frantic mother, a seven year old girl spilled drain all over her arms and legs. You can hear the girls screaming in pain in the background. When I got the temptation, my B to look for an answer there that says, tell the lady to rush that little girl to the emergency room. She has an emergency situation, but wait a minute. By the time she gets into the car and drives to the emergency room and gets there all that time, the gift that keeps on giving keeps on giving. And so the answer is not that. The answer is you tell the lady over the phone, man, get rid of the clothes the girl has. Take her to the shower, open the shower and have her under the running water for a half an hour and then bring her to the emergency room. Remember this sooner, the better. You might remember by the way at this time, those shower heads out in the corridor outside of the chemistry lab in your high school. The general wonder who's ever going to take a shower out here in the hallway? Well, nobody does. Those things are there. Sorry, if somebody gets doused with the chemical, they can be immediately irrigated. All right, let's look at the exception now. Being a number eight, a depressed teenage girl who happens to be your next door neighbor, attempts to commit suicide by drinking liquid blunder. We think a few minutes of doing it. She's frantically asking for help and you're called to administer first day. Well, now unfortunately, we cannot tell this young lady to go open your mouth under the running water and be there for half an hour. You cannot do the massive irrigation to the esophagus that we can do elsewhere. Here, we will have by necessity to play chemist, but we do it in a very gentle way. In this case, it is alkaline that she drank. Either diluted vinegar, orange juice, lemon juice, something like that would be appropriate for her to swallow. If we had been told that acid was responsible for the injury, then milk or egg whites or anti acid, again, very gentle neutralization. All right, the next kind of special type of burn is the electrical burn. And I'm confining my remarks here to the high voltage electrical burns to the big power lines, not the outlet by the wall. And the same way that I describe to my students, you know, the chemical burn by the essence of what's wrong with it. The essence in the case of electrical burn high voltage is that there is far more tissue destruction than appears to be when you look at the patient. In fact, there are physical reasons for that. Different tissues of different resistance to the flow of electricity. The bone happens to be very resistant to the flow of electricity. So the electricity goes through a bone hits the bone to very high temperature. The muscle next to the bone is cooked to a crisp, but the tissues that are closer to the surface are not. And those are the ones you can see when you examine the patient. The number nine while trying to hook up illegally to cable TV, an unfortunate man comes in contact with a high tension electrical power line. He has an entrance burn wound in the upper outer thigh and an exit burn lower on the same side. And this is in fact what you see in a big electrical burn two little holes where the electricity went in, where it came out. But believe me between those two, everything deep inside is cooked to a crisp. So the patient will need very extensive surgical debris, potentially amputations from all the dead tissue. But we have a number of other issues. All of that dead muscle is going to free up myoglobin. So we got to deal now with myoglobinemia, myoglobinuria issue as we did with the cross-in-in-jumps. Those need to be monitored for any present, lots of fluid, osmotic, diuretics, alkalination of the urinary, but there is more. When that jolt of electricity goes through the body, every muscle in the body contracts and contracts strongly. We often see posterior dislocation of the shoulder. We often see compressions of retiebral bodies from those muscle contracts. We have to look for those. As a more long-term sequela, cataracts can develop and also a demilinization, you know, problem later. Number 10, we're now beginning to deal with burns in the more traditional sense. Burns from fires, burns from hot stuff. A man is rescued by firemen from a burning building. On admission, it is noted that he has burns around the mouth and nose. And the inside of his mouth and throat look like the inside of a chimney. There's a something that is well known to firemen and to people who deal with burns. But if the setting where the burn occurs is flame burns rather than hot liquids. And it's a confined environment, a building, a car, a plane, not the backyard, okay? It's a confined environment. The first thing to think about is respiratory burn. Smoking it, which is actually a chemical burn of the upper respiratory tree. Now, in this case, we have an added hint of burns around the mouth. The inside of the mouth looks like inside of a chimney. So we know the issue here is respiratory burn. Now, what are we going to do about it? The way to confirm the diagnosis that the respiratory burn has been sustained is fiber. optic, wrong-cost, we look and we see the damage that was done. But the way we decide how to handle the patient is actually given by blood gases because the only therapy that is effective for the respiratory burn is the respiratory support that may be needed if respiratory function is compromised. You see at one time we used to think that the patient with respiratory burn benefited from steroid therapy or from antibiotics. It was even at one time the thought they all needed trick you to me right away. None of these has been proven to be a benefit. They may need an airway but if they do it can be put the regular way. And on the other hand what they really need is respiratory support if and when the respiratory function deteriorates. And so if the question were to be phrased how do you confirm the diagnosis your answer would be fiber optic, wrong-cost could be. But if the question were to be framed how do you judge the need for therapy or how do you monitor the patient the answer would be blood gases. And let me add that in addition to the blood gases there's another thing you want to monitor. The patient was in a confined environment breathing smoke. May very well also be breathing carbon monoxide. So monitoring for carboxy hymn of loving is always part of the management. So let me repeat then the management for the patient with the respiratory burn. The patient who sustained burns in a close environment from flamed lots of smoke. We monitor blood gases, we monitor carboxy hymn of loving and we respond to the need either for respiratory support. In the case of carboxy hymn of loving the therapy is 100% oxygen to breathe because that shortens the lifetime of the carboxy hymn of loving. All right, number 11 brings us to another issue related to burns. The patient has suffered fair degree burns to both of his arms when he's shared caught on fire while lightening the backyard barbecue. The burn areas are dry, white, leatherly and aesthetic and circumferential all around arms and forearms. The issue here is not the respiratory burn even though these were flame burns and it's shared caught on fire because this guy was out in the backyard. The smoke dissipates. This is not the confined space where smoke concentrates. The issue is a different one and the keyword that alerted you to it is the word circumferential. Let me explain. Underneath a third degree burn, there is always a lot of fluid that escapes from a circulatory space and it's trapped as a demon under the wound. A third degree burn I might have had the skin that has been char becomes a thick, leatherly, unyieldy scar that doesn't have the flexibility and the pliability of normal skin. Well if a patient simply has a square patch of third degree burn in the middle of his back, all the swelling underneath that can easily push the scar up and nothing happens. But if you have a circumferential burn all around that extremity, the skin all around has now been converted to the unyieldy, no longer pliable, no longer flexible skin that is now an scar. And underneath that there is a lot of fluid accumulating. So now you have a demon and no place to expand and that's going to cut off the circulation to the extremity. So the answer you're looking for in this vignette are the ones that are centred upon monitoring of a circulation in that extremity. Monitoring pulses, monitoring capillary feeling, perhaps a little more elegant and more technical way Doppler studies of a flow, but those are the answers you're looking for. Any fit says on the vignette that the pulses have disappeared, that the capillary feeling is gone, that the Doppler signal says there is no flow, then we do scar autones. That means we cut the scar in two lines and two places on the extremity to enable that extremity to swell. And in fact this is dramatic. We can do these things at the bedside, we don't need anesthetic for it, the skin is already anesthetized, full thickness skin has no innervation anymore. And we don't even need sterile conditions because that's already heavily contaminated dead skin. This is done at the bedside and within minutes the block returns to the hand and improves tremendously. If you have a vignette where the circumferential burn is in the trunk, the issue then will be the inability to expand the chest and breathe. The patient will again need the scar autones, now they'll be done like the breastplate. We make four cuts all around to free up and allow the chest to expand. So that's again the key meaning of that word circumferential when you find it in the context of a very question. All right now the year number 12 please pay attention to it. This is one with a tremendous probability of being on the next time. Let me tell you why. When this exam was designed an honest effort was made to make the exam socially relevant, to make it touch upon issues of prevention, issues of medicine interfaces with things other than purely the treatment of a particular disease entity. But it's difficult to write. Good examination questions that emphasize social issues and behavioral patterns and things like that. But here is a good example of where it can be done. The year number 12, a toddler is brought to the ER with burns and both of his bottles. The airs are moist, have blisters and are squeezedly painful to touch. The story is that the kid accidentally pulled a pot of boiling water over himself. That's not what happened. The least important part of his question is the description of the moist blisters painful to touch, which by the way, identifies second degree burn. The least important thing here is your choice of his simple self-adviance and to cover those burns. The big important thing is that this is in fact child abuse. All the personnel of emergency rooms are alert to the presentations that indicate child abuse. Burns on both bottles. That's not the pattern. If the kid had truly gone to the stove and pulled a pot of boiling water, he would have been drenched from head to toe. This is a child that was held by arms and legs and deep into boiling water. Yes, it can happen. Another example of this might have been the glove pattern burn affecting a hand or the sock pattern affecting the foot. The hand was immersed in boiling water. The foot was immersed in boiling water. So the real important issue of this question is the identification that this is in fact a case of child abuse and the necessary referral to the proper authorities.