 Welcome back to emergency medicine video series. This is burn part 2. Remember the burn patient from the fire? What complications do we worry about in him? In this video, we'll talk about the major complications of thermal burn. The complications of thermal burn include fluid loss, airy complications, edema and chemical exposure. We'll go through them one by one. First, fluid loss. At the cellular level, burn causes a big inflammatory response, causing capillaries to become leaky. This fluid then leaks into the interstitial space. Due to the leaking, it can cause two problems. One, because of the fluid loss, it can cause hypotension. Second, because of the leaking, it can cause a lot of edema in the surrounding tissues. Let's talk about the volume loss first. Since the patient has often lost a lot of intravascular volume, burn patients need a lot of fluid. How much fluid is a lot? We estimate this by using a specific formula. The formula we use is called the Parkland formula. This formula estimates how much fluid we should be giving patients. Specifically, it is used to estimate the amount of fluid given to patients who had more than a second degree burn. So it is second, third or fourth. The formula goes as follows. In the first 24 hours from a burn, the patient needs a total of four cc per kilogram times their weight in kilogram times percentage of the total body service area that's burnt. This number you get will have a unit in cc of fluid, usually ringer's lactate. So note that the weight is in kilogram, not pounds, and the percentage burn is the amount of burn that includes second degree, third and fourth. Not first. Out of this amount that you get, the first half should be given eight hours post burn, not post when they show up in the hospital, and the rest of it, so the last half should be given 16 hours after that eight hours is done. So in the first 24 hours, the whole thing should be given. Let's try this out. So remember the patient that we had has a calculated percentage area burn of 36 percent. That includes second and third degrees, so partial thickness and full thickness. He was set, say, burned four hours ago, and we estimate his weight at around 70 kilogram. So how do we use the Parkland formula? Here's the four cc times his weight times his percentage burn. You're put in the calculator. It ended being something like, so it ended being about 10 liters. So remember he was burned four hours ago, so we're kind of behind by four hours. So the first half of this 10 liters, there are four or five liters, we need to give it in the next four hours. And it being about a bit more than a liter per hour. And then the next five liters will be given the next 16 once the first five liters is given. So you can see there's quite a bit of volume that's given to these patients. And we often try to estimate it using the Parkland formula. It doesn't work every time because most patients sometimes even need more, but this is a great place to start. So the next problem, remember that we have leaky capillaries is not just that their volume loss is now the edema has now gone into the insistential space. The problem is the most pronounced as we give more fluids because more fluids will then leak into the space even more, causing more problem for us. The most worrisome place that we worry about edema is of course at the airway. This is the part that we worry about the most in the emergency department. If you look at a cross section of an airway, once a thermal burn sets in, it can cause any structure inside this box to swell, making your intubation very difficult the longer you wait because the more swollen they'll become. Therefore, intubation in a burn patient needs to happen early. That is even before the swelling has set in. And it needs to be done in anybody that you are suspicious of a thermal burn to the airway. Well, how do you tell who has a thermal burn to the airway? You do this by inspection and for listening. So in a patient with a potential thermal burn, you might be able to see sut in the mouth or sputum. You might be able to see singed nasal hair. You want to listen to voice changes such as hoarseness or particular stride. And if a patient has a visible burn on their face, it's very likely that their airway is going to have a burn as well because they inhale the vapors and the steam. Those are the people that you want to intubate early, even though they may look fine now. Remember, a patient might look like they're fine. The edema will happen quickly, particularly because we're very aggressive with fluid replacement. If you don't intubate now, the swelling will make the intubation impossible. A second problem with edema happens in conjunction with full thickness or third degree burn. In those burns, the skin is charred and loses its elasticity. That is called an eschar. If you have edema in the subcutaneous tissue underneath the eschar, the skin cannot stretch anymore. That will cause pressure buildup underneath the skin. In the chest, it will cause difficulty with ventilation because now the chest wall is extremely rigid. It simply will not rise. In the extremities, this eschar and edema will cause compartment syndrome leading to distal ischemia. How do we fix eschar? We do this by doing an escharotomy. Basically cutting the skin down to its full thickness to release the skin, therefore it can stretch. It is done in various parts of the body. You can see one being done on the leg here, and you can see one done here on the chest to make the chest wall more compliant while the patient is on the ventilator. What about specific chemicals from Fireburn? We worry about two specific chemicals from Smoke and Fire, carbon monoxide and cyanide. Carbon monoxide will bind to hemoglobin much better than oxygen. It will cause various neurological deficits, cardiac ischemia and ultimately lead to death by cardiovascular collapse. The treatment of carbon monoxide poisoning is chasing it by oxygen. It can be administered just in regular air, and the half-life of carbon monoxide clearance about four hours in room air. In 100% oxygen, the half-life of clearing is an hour. And patients who are undergoing hyperbaric oxygen treatment, that is oxygen that's being pressurized at higher than atmospheric pressure, the half-life of clearing carbon monoxide from the body is about 20 minutes. The second chemical that we worry about is cyanide. It strangulates the mitochondria, causes lactic acidosis. We won't talk about it here, but there are specific antidotes for cyanide. In the summary, we discussed the complication of burn, mainly fluid loss, airway issues, edema, and the two chemicals associated with fire. In part three, we'll put it all together in managing our burn patient. Thank you for watching.