This is the result of a conversation my partner and I were having the other day at work. Squid, as he is known, is a very intelligent and well-spoken individual. He's considerably younger than I am (I am older enough than he is that I could be his father, and sometimes I feel like I'm being a parent with him, but that's a story for another day :-), and he is a U.S. Navy veteran. When he is not working with me on an ALS ambulance he is a husband and father, and he serves as a Naval Reserve Hospital Corpsman. I'm proud to be associated with this young man, and I am very happy that he and I work together, as I believe our skills complement each other.
Well, one of his skill sets, thanks to the Department of Defense, is a strong background in unconventional medicine and tactical/battlefield medical care. We have some rather interesting conversations about applications of care, mostly when it has to do with controlling bleeding in an adverse. The combat medical provider works off of a slightly different set of priorities than those of us in the civilian arena. Where those of us in civilan EMS operate with the basics being A - B - C (for Airway, Breathing, and Circulation), many military-trained providers use the acronym MARCH, which stands for Massive Hemorrhaging, Airway, Respiration, Circulation, and Hypothermia. Makes sense to me - with massive trauma and any sort of higher-level medical facility possibly hours or days away (sometimes), getting bleeding from a gunshot wound under control before assessing the victim's ability to protect his own airway has more priority as someone shot could bleed out in the time it takes to secure their airway. On the other hand, depending on the severity of the wound, what if it takes a while to get the bleeding controlled and the victim has a compromised airway? The brain can only last 4-6 minutes without oxygen, and while I realize bleeding can happen fast, so can brain damage from anoxia. So what should you really do first? I suppose it depends on the victim's condition and their initial presentation. I guess where he and I differ on this and some of the other topics we talk about is that he sometimes will go "by the book" and perhaps not consider the patient's condition upon presentation. I could be wrong about that, but I think that happens.
Another thing we've talked about (and this is the motivation for this post) is the issue of IV fluids in the field. His point of view is that actually running fluids on a trauma victim or a combat casualty is something that should be done at an absolute minimum. The reasoning he uses is good to a point: he points to the breakdown of clotting factor when volume expanders are introduced into the body ("two large-bore IV's run wide open with Normal Saline"). I actually agree with his premise, but only to a point, as I said. There are other factors to consider. First of all, you can't look at a casualty or a trauma victim in a vacuum; with combat casualties as well as with someone who is a victim of a fall, an MVC, or some other sort of traumatic insult, you have to consider the environment, whether or not the person is able to maintain their own level of homeostasis without any external support (the issue of Hemodynamic Status comes to mind here), and in the case of some of the folks we see, whether or not there was a medical cause for their injuries, i.e., "did the stroke cause the accident or did the accident cause the stroke?" I'm inclined to think, however, that in a combat environment medical conditions would be minimized as most combat soldiers are in excellent physical condition to start with. It's just us old folks that have the other things going on.
One of the things we discussed recently was isotonic solutions, the two most widely used being Normal Saline and Lactated Ringers solution. One problem with LR is that it is incompatible with blood products, mostly due to the Calcium content. Normal Saline is not; it is used to facilitate introduction of blood products all the time. I asked him if military medical units used Plasma-Lyte - he didn't know what it was. Basically, Plasma-Lyte is a saline-based solution that has a higher level of Potassium Chloride than Lactated Ringer's solution, and PL also does not contain Calcium Chloride - LR does. I suspect this is what makes PL compatible with blood products, and I guess it would make sense that having a Calcium compound would cause problems with the intake of blood products. I don't know enough about the chemistry involved, but my inclination is to think it has to do with clotting factor. Does Calcium Chloride interrupt or enhance the blood chemistry somehow? I don't know, but I would like to find out.
When I took my PALS refresher last week we had 3 nurses from the PACU of the hospital I was taking the class at in the class. They were talking about PL and it got my attention so I asked them about it, how it worked, and what benefit there was in using it. They summarized it pretty well explaining its benefits as I outlined them above. I've done a little bit of research on what it is and does; lots of good information out there. I'm continuing to read about it as I think there is more that I can look at. I'll talk about this more as I learn more.