I want to rant about chest seals. And I want to critically look at them from a practical perspective. There must be a dozen different brands in the US market these days. What I find most interesting, is that when you look at the most recent military casualty data, chest wounds are almost non-existent anymore. Armor has become so effective that wound patterns are effecting other parts of the body. So why does everyone think they should build a better mouse trap, and an even better question is why is everyone focusing on building a better valve?
The Asherman Chest Seal was the first true chest seal with a valve that I am aware of. Very quickly into the GWOT, it became obvious that the glue was not effective in real life circumstances. Then along came hydrogel, with it’s tenacious adherence to bloody skin. But then came more valves…in every size, shape, color and flavor, and it left me asking why. A valve, in order to function properly, requires penetration of the chest wall that will not seal itself. If chest wounds are rarely occurring, then I can only assume that chest wounds large enough to not self seal themselves are even rarer. And lets be honest, most penetrating trauma to the chest, unless it is massive, will self seal with postural changes. Yet this is the only type of injury where a valve may be effective. That is as long as the pressure in the chest is enough to overcome the pressure required to open the valve, and that the valve doesn’t clot shut and that the care provider actually lined the valve up with the hole in the chest, and all the other problems with valves.
I still truly believe that valves on chest seals are a gimmick so it surprises me why so much time, effort and money is spent by companies to come to market with yet another valved chest seal in an already over-saturated market. The measure of a good chest seal should be how many times it can be removed and reapplied and still effectively stick. Generally speaking, hydrogel is hydrogel. After all, in the now relatively rare circumstance of the open chest wound, the treatment should not be to rely on the valve. It essentially gives a false sense of security and the care provider may apply it and then forget about the chest injury and move on. Chest injuries are high maintenance casualties! These casualties must be closely monitored for the development of a tension. If and when that occurs, before any needles are thrust into the chest, the seal should be removed, the tissues in the chest wall compromise realigned with a digit, and even slight pressure applied to the chest, then the seal reapplied. That is effective, non-invasive chest injury maintenance, and might have to be redone multiple times as the tension redevelops. Only when that fails should a needle decompression be conducted. Hence the benefit of a seal that can be removed and reapplied. This bypasses the requirement for the rare perfect conditions that allow a valve to function properly.
But this is just a post on the interweb. Please don’t take my word for and research it yourself with a critical eye.