Trials Are Underway
Dr. Glatter: In terms of adoption of such a device, it certainly has to go through rigorous testing and maybe some trials. Hannah, where are you at with vetting this in terms of any type of trial? Has it been compared head to head with standard tourniquets?
Ms. Herbst: Yes, we’re currently doing large amounts of field testing. We’re doing testing on emergency vehicles and in the surgical setting with different customers. In addition, we’re running pilot studies at different universities and with different organizations, including the military, to make sure that this device is effective. We’re evaluating cognitive offloading of people. We’re hoping to start that study later this year. We’re excited to be doing this in a variety of settings.
We’re also testing the quality of it in different environmental conditions and under different atmospheric pressure. We’re doing everything we can to ensure the device is safe and effective. We’re excited to scale and fill our preorders and be able to develop this and deliver it to many people.
Dr. Glatter: I was wondering if you could describe the actual device. There’s a brain part of it and then, obviously, the strap aspect of it. I was curious about contamination and reusability issues.
Ms. Herbst: That’s a great question. One of the limitations of conventional tourniquets on the market is that they are single use, and often, it requires two tourniquets to stop a bleed, both of which have to be disposed of.
With AutoTQ, we have a reusable component and a disposable component. I actually have one here that I can show you. We have a cover on it that says: Stop bleed, slide up and power on. You just pull this cover off and then you have a few simple commands. You have powering the device on. I’ll just click this button: Tighten strap above bleeding, then press inflate. It delivers audible instructions telling you exactly how to use the device. Then, you tighten it above your bleed on the limb, and you press the inflate button. Then it administers air into the cuff and stops the patient’s bleed.
Tourniquet Conversion and Limb Salvage
Dr. Glatter: In terms of ischemia time, how can a device like this make it easier for us to know when to let the tourniquet down and allow some blood flow? Certainly, limb salvage is important, and we don’t want to have necrosis and so forth.
Dr. Antevy: That’s a great question. The limb salvage rate when tourniquets have been used is 85%. When used correctly, you can really improve the outcomes for many patients.
On the flip side of that, there’s something called tourniquet conversion. That’s exactly what you mentioned. It’s making sure that the tourniquet doesn’t stay on for too long of a time. If you can imagine a patient going to an outlying hospital where there’s no trauma center, and then that patient then has to be moved a couple hours to the trauma center, could you potentially have a tourniquet on for too long that then ends up causing the patient a bad outcome? The answer is yes.
I just had someone on my webinar recently describing the appropriate conversion techniques of tourniquets. You don’t find too much of that in the literature, but you really have to ensure that as you’re taking the tourniquet down, the bleeding is actually stopped. It’s not really recommended to take a tourniquet down if the patient was just acutely bleeding.
However, imagine a situation where a tourniquet was put on incorrectly. Let’s say a patient got nervous and they just put it on a patient who didn’t really need it. You really have to understand how to evaluate that wound to be sure that, as you’re taking the tourniquet down slowly, the patient doesn’t rebleed again.
There are two sides of the question, Rob. One is making sure it’s not on inappropriately. The second one is making sure it’s not on for too long, which ends up causing ischemia to that limb.
Dr. Glatter: Hannah, does your device collect data on the number of hours or minutes that the tourniquet has been up and then automatically deflate it in some sense to allow for that improvement in limb salvage?
Ms. Herbst: That’s a great question, and I really appreciate your answer as well, Dr Antevy. Ischemia time is a very important and critical component of tourniquet use. This is something, when we were designing AutoTQ, that we took into high consideration.
We found, when we evaluated AutoTQ vs a CAT tourniquet in a mannequin model, that AutoTQ can achieve cessation of hemorrhage at around 400 mm Hg of mercury, whereas CAT requires 700-800 mm Hg. Already our ischemia time is slightly extended just based on existing literature with pneumatic tourniquets because it can stop the bleed at a lower pressure, which causes less complications with the patient’s limb.
There are different features that we build out for different customers, so depending on what people want, it is possible to deflate the tourniquet. However, typically, you’re at the hospital within 30 minutes. It’s quick to get them there, and then the physician can treat and take that tourniquet down in a supervised and controlled setting.
Dr. Glatter: In terms of patients with obesity, do you have adjustable straps that will accommodate for that aspect?
Ms. Herbst: Yes, we have different cuff sizes to accommodate different limbs.