Medical Monday, the Walking Blood Bank

In class, I always like to discuss how when a casualties blood pressure is lower than 80 mm of mercury systolic (absent radial pulse) and we decide to raise their blood pressure, we only have one option really. That is low titer whole blood. The fudd EMS providers are furiously typing away right now about how you should just achieve two large-bore IVs and push two 1 liter bags of Normal Saline. That’s what they were taught in 1985, so it should still work just as good now. I mean, we still perform heart surgery the EXACT same way we did in the 80s. Medicine never changes, it is settled science. Wait, you mean to tell me that medicine is constantly evolving as we learn new info and that maybe we might need to adapt as we learn better? And here I was still eating “I can’t believe it’s not butter” because my parents’ doctor told them it was healthy. Jeez, I wonder what else they’ve gotten wrong….

Anyway, back to blood. If you check the TCCC guidelines as published on http://deployedmedicine.com you’ll see that the preferred fluid of choice for resuscitation needed due to blood loss is whole blood. Without getting too deep into the sciencey stuff involved, NS (normal Saline) can not transport oxygen or waste products, it can not help with clotting, and won’t even stay in the blood vessels very long. Blood does all of those things and more. It’s pretty cool how much it actually does. That isn’t even including the PH differences between blood (7.35-7.45) and NS (5.5) which can lead to acidosis. Acidosis is part of the lethal triad and we don’t want to have to spend our time trying to stop it once it has started.

What the hell even is low titer whole blood? A blood titer is a measure of antibodies. And the antibodies we are concerned with are those that could attack antigens that are present in other blood types. It’s a fairly normal blood test that you can have performed at your doctor’s office or at any lab facility (like LabCorp). This is important to make sure that the blood we are transfusing does not cause a hemolytic reaction. This is where the antibodies in the transfused blood can react with the antigens in the recipient’s blood and form clot-like clumps which can ultimately lead to death. Blood transfusions are not a lackadaisical task that can be performed by anyone with a pulse. It requires very specific training and equipment to perform properly. That being said, they are not something that is outside of the partisan medics’ wheelhouse with the proper training (preferably training received while the grid is still up). This is something most ER and ICU providers are familiar with. And is another reason why having someone with those skills in your group is extremely important.

Well, where do we even get low titer whole blood from? This isn’t something that you can feasibly store long-term at a retreat. Fresh whole blood only lasts 30 days when refrigerated and 90 days when frozen, not to mention how are you going to heat it back up (hint, the answer is not to throw it in the microwave on a defrost setting). The best way to store whole blood is the same way you store meat. On the hoof. No, I am not recommending cow’s blood. But I am talking about the walking blood bank. The walking blood bank is a concept that stems from the military. Why store massive quantities of whole blood in the various blood types you will need when you can just store transfusion kits and pull the blood as needed. It originated as something done at the MASH level in Vietnam and has now been pushed down to the platoon medic level in the GWOT era. The idea is instead of waiting for the casualty to get to a field hospital to receive blood, do so when appropriate in the tactical field care or tactical evacuation care stage. This has absolutely had a positive effect on preventable combat deaths (around a 44% decrease in combat-related mortality)

This article has already gone on long enough. In part two we will take a look at a simple transfusion kit and discuss how to set up your walking blood bank for success.

Want to learn more? We definitely cover this topic in the Partisan Life Saver course. Come on out to a class, I’d love to have you out.