Hello,
I'm sorry but I wasn't suggesting that it was up to a technologist to make the final decision on the use of equipment in Electrosurgery. Though I think we should be more supportive in finding answers about electrical safety so the Trust can come to a more informed decision.
I've had time to think about this and I'm interested to hear what other people make of some ideas knocking around in my head.
Firstly the idea of two current paths crossing, yes there would be increased power at this point, but it would only be at most the sum of the two output powers. i.e. if one surgeon was using 100W and the other 120W the maximum this could be at any point would be 220W. I've assumed that reflections would be negligible. As Richard Ling has already mentioned best practice is to keep the return paths as short as possible so to reduce tissue heating. So restricting the output powers used would seem a more practical solution.
But then I started wandering whether it was due to the interaction of the two current paths! As we all know during electrosurgery large amounts of current surges though the patient body without causing shock due to its high frequency nature. But if to two high frequency signals are mixed and there is a small difference between the frequencies, a lower beat frequency is produced. This would give rise to the potential of a macro shock! I can see that having the correct phase in a system designed with two outputs is vital, as there is only one return plate. What I am very interested to hear from other people is whether they believe that two current paths from two floating generators would interact, because I'm not convinced. And surely with this practice being widespread throughout the country there should have been patients electrocuted as a result by now.
I think the issue brought up be Double D of burning on the edge of a plate is interesting, though the same would be true with single diathermy use. As there have been no known cases I would expect that there probably isn't a problem.
I'm eager to hear other people's thoughts,
Adrian.
