What Are 3a and 3b Degree Burns?

[nomadreid]

TL;DR

Are third degree burns also subclassified into 3a and 3b burns?

I have come across a discussion of a therapy that is listed in a (translated) Russian text as being good for "3a and 3b degree burns", without the text explaining what the difference is between these two subclassifications of third degree burns, and I do not find that distinction in (English) online sites discussing the degrees (one to four) of burns. Is there such a subclassification in the West, or is this a Russian thing?

 

[Rive]

This is only about 2/a and 2/b, but still might be helpful.

 

[nomadreid]

Thanks very much, Rive. That tells me that there is such a subclassification, and the explanation of the distinction for second degree is easy enough to carry on through for the third degree.

 

[Rive]

Well, I'm not sure. Based on the previously linked paper I could identify the 2/a as 'superficial' and 2/b as 'deep' partial thickness (2nd degree), so it is a variation of terminology: but there seems to be no such subclassification for third grade burns - or I could not find it either.
So at the end it is just likely that the subclass can be applied, but not sure.

 

[nomadreid]

Hm, good observation: it is possible that the author himself decided to extend the standard classification of 3rd degree via analogy to second degree, making it effectively a coined term.

 

[Tom.G]

When this thread was first posted I did a short online search that indicated, at least in the US, that 3rd degree burns can be classified as necrosis of the skin layer OR, more severly, as necrosis of the underlying tissue. Could this be what /a /b refer to?

Sorry, don,t remember the link.

EDIT:
Ahh, browser history to the rescue!
https://www.medicinenet.com/script/main/art.asp?articlekey=2557

 

[nomadreid]

Thanks, Tom.G. Even without the link that there was the distinction, your information was helpful; I do not myself need to write a paper on it, just to understand someone else's. Nonetheless, a good source is always nice, so I clicked on the link you included, and I presume the distinction you mentioned appears as the part that I underline in the following quote from that source: "Burn, third degree: A burn in which the damage has progressed to the point of skin death. The skin is white and without sensation. In extreme cases damage may extend beyond the skin and into underlying tissue. In these cases the skin may be blackened or burned away. Unless skin grafts are feasible, loss of the affected limb, permanent disfigurement, and even death are likely in such severe cases."