 Hello and welcome to emergency medicine video series. You're working in the emergency department, paramedics called and they're now bringing in a patient who is rescued from a building fire. How do you prepare for a patient like that? What is the approach to burn management in the emergency department? In this series, we'll focus on thermal burn from hot liquids or fire. In part one, we will discuss how to diagnose the severity and extent of burn. We first need to know how deep the burn is. To do that, we need to know what normal skin is composed of. Normal skin is composed of a few layers. The top part is the epidermis. Underneath that is the dermis. And underneath that is subcutaneous tissue. Under that would be bone, muscle, tendons and so on. Burn is traditionally classified based on the depth of the skin that's involved. It's classified into first degree, second degree and third degree burn. This is the older classification. The newer classification separates the burn into superficial, partial thickness and full thickness. They're actually quite similar and we'll go through them one by one. But you can see that first degree burn really is superficial burn, second degree burn is partial thickness burn, and third degree burn is full thickness burn. Let's go through them. First degree burn or superficial burn. This is when only the epidermis is affected. So just right on top of here. A common example is a sunburn. Most of us have had that. The skin is red and painful. It heals and there might be some peeling of the skin. Usually heals in a few days and there is no scarring. In second degree burn or partial thickness burn occurs when the epidermis is affected and also some part of the dermis is affected. Because of the different depth of the dermis that's being affected, it is further divided into superficial partial thickness and deep partial thickness. A superficial partial thickness burn involves again the epidermis and now the superficial part of the dermis. So just the top bit in here and including the epidermis as well. They often produce thin watery blisters as you can see in the picture here. The skin is pink and is very tender. These kind of burn will heal in weeks and usually heal without scarring. Deep partial thickness burn involves the epidermis again and now a much deeper part of the dermis. So much deeper in here. And clinically they form thick wall blisters and the skin can be red or white based on how much capillaries they destroy during the burn. These burn will heal in a month or so but can cause scarring and contraction of the skin. Third degree or full thickness burn. It involves the epidermis and now the full thickness of the dermis. The skin has a leathery and white appearance. The nerves are burned and therefore there is decreased sensation. Third degree burn or full thickness burn will not heal by itself. Fourth degree burn involves the whole skin layer just like a third degree and now the underlying fascia, muscle or bone. This as you can expect can cause major disability. After deciding on the depth, the extent of the burn is described as a percentage of the total body service area. The most often used measurement is called the rule of nines. It is used to calculate the area involved in partial thickness or full thickness burn. So second and third degree. We don't try to calculate superficial or first degree burn. In this rule, 9% of the body service area is awarded to the whole face and head. 9% is given to each arm that includes the front and back, 18% to the anterior trunk, 18% to the posterior trunk, 18% for each leg again that includes the front and back and 1% to the genitalia. It gives you a rough estimate of the percentage of the body service area that's burned. This is a useful and commonly used rule to estimate burn area. If the burn areas are scattered, we can use the patient's palm area as 1%. So this will be about 1% and we use this to estimate the percentage burn. There is an inverse relationship between age and burn size survival. The older the patient, the less likely they will survive in the same amount of body service area burn. Also, the deeper the burn, the worse the prognosis. Let's see if we can calculate the area of burn in this patient. Let's say the burn involves his anterior chest and abdomen, the whole left arm, top and bottom, front and back and his whole head and neck, anterior and posterior. How much body service area is being involved? So anterior trunk as we said is 18, the whole left arm is 9 and front and back of the head is 9%. So the total area of burn in this patient is 36%. So in summary, review the classification of burn severity and extent from first or ship official to second degree or partial thickness to third degree or full thickness burn. We talk about how to estimate the area. In part two, we will discuss the complications of burn. Thank you for watching.