Energy options in gynecologic surgery

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So look at this real-time thermography here of how literally the thermal margins intrinsically plateau at about 100°. And that is determined by the construction of the jaw, having nothing to do with generator output.

Now, take a look here at an animation that would help us. And so here we have your conductive particles close together, conducting electricity. As the plastic starts to heat up, what’s going to happen to these particles? The particles are going to spread apart and, naturally, certain zones of the jaws are going to stop. And when they then cool off, these spirals will come closer together and they’ll start conducting again. So here we have a reconfiguration. You see 100° becomes nonconductive. Now, of course, as they cool, they come closer together again and they’re going to conduct again. So you have this mirror infinite number of microcircuits occurring until finally the current is self-regulated and turns off, based on where the jaw is in impedance of the tissue. Secondly, if you look at a Kelly clamp, a Heaney clamp, or any bipolar electrosurgical device, and you measure the pressure, and you know this intuitively, as surgeons, pressure is greatest at the heel and is least at the tip. We’ve got to change that—that’s the physics of the device. And unless you increase the girth of a device, as you increase the length this becomes even dramatically more problematic. So of all the devices up to this point, you’ve got high pressure at the heel, lower pressure at the tip. So for vessel sealing—think about it—you want high compressive forces—remember, low energy a certain amount of time—the tip of the instrument in certain cases does not get sealed very well in certain devices, because we can’t get the same compressive pressure from the heel to the tip by the physics. So the maximum compression is at the heel of the clamp.

Now take a look at an I-Blade™, I-Beam configuration, that now is part of the ENSEAL device, which to me is one of the most innovative features.

So here you have a blade coming down, but it’s an I-Beam, and since it’s an I-beam, it pulls across, and the pressure is absolutely the same at the tip as it is on the heel and, as a result your seal, is going to be absolutely the same histologically whether you’re looking at the heel, midway in the clamp, or at the tip histologically, and you’re going to get a uniform cut. A very unique discipline here.

And you can see this cut, and you can see, in fact, it is highly predictable, and minimal thermal margins.

And lastly, very interesting. And there’s a background to explain this third feature.

Think about the 2 fundamental principles of electricity that can’t be changed. One is that electricity always seeks to ground, which is the earth. We cannot change this reality. And the other reality you cannot change in electricity is electricity is always going to follow the path of least resistance. You cannot change this.

So think about a conventional bipolar electrosurgical device. Conventional bipolar electrosurgical devices have a positive and negative pull—this is the way they’re set up.

So look at the way the current flows. The current initially is going to flow from positive to negative, but as the tissue heats up and gets drier, the current is going to try to seek other paths to make the connection of the circuit. And it moves the current more laterally, in a progressive fashion, until finally the resistance is so high it can’t go more laterally. But this literally tends to push the current lateral to the jaws to complete the circuit. Electricity seeks the path of least resistance. Now, there is an offset jaw configuration of the electrodes on the ENSEAL device that, in fact, keeps the current within. Because if you look here carefully, you see a positive/negative, but the positive is surrounded by negative poles. So as a result, what this does is this isolates the current to within the material that’s between jaws and keeps it from spreading laterally, as compared to the other portion of the device.

So to recap, I talked to you about electrode configuration, which are the conductive elements in there, the nano spiral technology, that expand and contract and keep the temperature at about 100°. It doesn’t matter how long you’re there, it’s going to stay at that temperature. You have an I-Blade that overcomes all of the intrinsic problems we have in the context of heel versus tip pressures on vascular and hemostatic clamps. And we have an interesting design of the electrodes that tends to keep the current within the jaws rather than making it spread laterally to complete the circuit through the path of least resistance. So that’s not the only device that we use for surgery. And, of course, there are many devices that are complementary. And, for me, the most complementary device because it’s so specifically designed for soft-tissue dissection, we’re talking dissection instrument, is the Harmonic® Ace™ device.


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