Treating war wounds with fish skin

Steve Jeffery who is a burns surgeon and professor of wound studies at Birmingham City University. Steve spent two weeks in 2020 treating dozens of Armenian combat soldiers who were injured in a war with neighbouring Azerbaijan, and took a special piece of kit with him...

Steve - In my suitcase with me, I brought a number of items. Amongst that was some fish skin, which I knew from previous experience would be particularly handy in a setting where you have probably more patients than you know how to deal with and when there would be some challenging wounds.

Chris - When you say fish skin, do you literally mean the skin of fish?

Steve - Yes, it has been processed a bit, but not a lot, which is the beauty of the fish skin. It's a byproduct of the fishing industry. There's a fish factory in northwest Iceland where they used to throw the fish skin away, and then somebody had a light bulb moment of saying, well what could we do with this? It's descaled and then it is pasteurised and then it's freeze dried. From that moment on, you can keep it at room temperature on the shelf.

Chris - And what do you do with it? How is it used?

Steve - You rehydrate it with water or saline or whatever you've got for about a minute, and then that makes it nice and pliable. Then, you put it onto your wound that you will have debrided. Combat wounds particularly are often very dirty and contaminated with lots of horrible bits and pieces from the battlefield. When you debride a wound, what we mean is that we take away all the dead and the dying tissue and leave a nice healthy bed. Then, we have to put something on as a temporary cover, and the fish skin works very well in that role.

Chris - Do you have to change that rather like a wound dressing or do you put that down in there and then leave it for the duration of the healing?

Steve - It'll start to degrade, the body doesn't like having anything next to it, but also at the same time it encourages blood vessels to grow through it. It's very good at encouraging the growth of granulation tissue as well as being an antimicrobial there. If you think about the life of a fish, the ocean is full of bacteria and they're constantly swimming through bacteria. So there are proteins in the structure of the skin which are innately antimicrobial.

Chris - And a person doesn't become sensitised, like develop an allergy to it, because they're in close contact with it? Could you keep on using this for a person?

Steve - The only people that can't use this are people who are allergic to fish, as you can imagine. But even those people, when you are actually truly allergic to fish, it's actually a protein within the muscle of the fish that you are usually allergic to, not the skin. So the vast majority of people will not develop an allergy to this, so it's used subsequently.

Chris - And what sort of a difference does this make? Have you done head-to-head trials? I know it's very hard to take an equivalent injury and do a direct comparison, but have you got data before and after doing this to show that this really makes a difference?

Steve - Data in combat injuries is hard to get off, so you have to extrapolate. It's been used in burns head to head against allograft, which is where you take skin from a dead human. So it's the same species, but the problem with taking skin from another human is it has to be very highly processed in order to make sure there's zero risk that there's any viruses or prions or anything that we might not yet understand can be transmitted. Now it turns out that fishes, they also get viruses, etc., like all animals do, but we are so distantly related to fish that there's no viruses that affect fish that can also affect humans. So you don't have to do all that mega processing of the skin that you would if you're taking an allograft from another human or the alternative if you're taking another type of xenograft. So xeno means foreign species, from a pig, for example, but then it would also have to be highly processed because there's obviously risk of viral transmission from pigs to humans.

Chris - And just going back to my point which was, have you evidenced this is actually better to do this? Obviously it's one thing to do it, but if you don't know it's better, we don't know we're improving outcomes with this. So what's the evidence this works?

Steve - In the burns world, which is similar, you do a burn excision, so you do an excision and then you will often put allograft on. It's been shown to be as good if not better than cadaveric allograft in that situation. And also, in other wounds, not combat related wounds but say, for example, leg wounds, leg ulcers, etc., it's been shown to be very efficacious and the company that makes it are selling an awful lot of it around the world.