Third degree burns

Picture of third degree burns

Third degree burns

Third degree burns (known in the UK as deep thickness burns), are the deepest types of burn

What is a third degree burn?

A third degree burn is a burn of the full thickness of your skin (the epidermis and the entire dermis). They often look pale, charred or leathery

How do people get third degree burns?

Typically third degree burns are caused by flame injuries, such as when clothing catches fire or a person falls into a hot area (such as a barbecue). Less common causes include chemical burns, electrocution injury, or even lightning injuries. Any other cause of burns can also result in a third degree burn if the exposure is long and hot enough – for example if you touch a hot stove

Do third degree burns hurt?

Although a third degree burn is the deepest type of burn, it is also usually the least painful. Because a third degree burn affects the full thickness of your skin, all the nerve endings to the skin have been destroyed and so the burn is often completely painless. A burn is rarely purely third degree, though, and the edges may blend from third, to second, to first degree, until finally unburned skin is met. These more superficial burn areas may well be painful

Are third degree burns dangerous?

Generally, whilst small third degree burns may be of little consequence, some can be dangerous depending on the size of the burn. The size of the burn is worked out as a percentage of the ‘total body surface area’. As a rough guide, your palm and fingers are about 1% of your body surface area. In adults the head is about 9%, arms 9% each, legs 18%, back 18% and chest/abdomen 18%. The reason for being concerned about the size of the burn is that the higher the percentage of burn, the more serious it may be. Intravenous fluids are often needed for burns larger than 10% in children and 15% in adults. 

Additionally, as the skin has been damaged in a third degree burn, bacteria can now enter into the skin and bloodstream – this can cause redness, swelling and infection of the burn, or septicaemia and life-threatening illness (known as toxic shock syndrome)

How are third degree burns treated?

As described earlier, larger third degree burns are given intravenous fluids (usually over 10% surface area burns in children or 15% in adults). Fluids may also be given to patients with other injuries sustained at the time of the burn, airway injuries, etc. A catheter may also be required so that urine production can be monitored, which informs the clinician of how well hydrated the patient is. 

Third degree burns are often treated firstly with cleaning and dressings. These dressings may be simple non-stick dressings or ones which contain silver to fight bacteria, agents to promote healing etc. Whilst a third degree burn will eventually heal, it usually does so with scarring – for this reason many burns specialists will opt to remove the burn and perform a skin graft to speed healing and try to prevent problematic scarring and wound problems. Additionally the presence of large deep burns cause the patient to become very sick due to their immunological responses, giving more reason to remove a burn early and try to reduce the immunological drive

What are the long-term issues of a third degree burn?

Scarring – third degree burns will generally heal with scarring. Additionally, any surgery that is needed will leave scars. 

Scar contracture – if a third degree burn heals on its own and forms scars across a joint, then as the scar matures it may contract (shrink). This may lead to an inability to fully move the joint, and so surgery may be needed to release the scar. Even if skin grafts are used to reduce this happening, these can also shrink and so need further surgery in the future. 

Slow healing – third degree burns can take many weeks to heal on their own, and so burns specialists may use a skin graft to help healing. Occasionally a burn can heal up but with a thin, unstable scar – this can easily break down again and again, so surgery may be needed to try to get the area to heal fully.

Disfigurement – third degree burns, whether operated on or not, can leave scars that are very noticeable to you or to others. This is especially so when the burns are to the face. Whilst scarring can be improved by surgery or other means, there is unfortunately no way to completely remove them. The recent advances made in face transplant surgery may, however, provide hope for those with the most severe types of facial burn injuries.

Skin colour changes – a third degree burn will often leave an area of pigment change in the skin. This is usually in the form of a paler patch of skin, which can be permanent (hypopigmentation), or darker skin (hyperpigmentation)

The list of consequences is not exhaustive, and you should discuss possible burn complications and treatment with a specialist. The information provided is as a guide only and you should discuss matters fully with your specialist regarding any burns or treatment required

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