Pacemakers and welding

"Ignoramus6829" wrote

Any problems

Or the wearer hits the deck.

Steve

Good description.

The leads to the heart likely will act as an antenna...picking up the welder's RF emissions and feeding them to the digital circuitry to affect the internal processor.

I really suspect that during testing a pacemaker is NOT subjected to this intensity of RF emissions...a cell phone or a microwave likely...a welder not likely.

If I had a pacemaker, I would not be welding.

TMT

I don't know if welding with the pacemaker is good or not, any way.... I know of an old old guy who has a pacemaker and puts his spare arm across his chest as a "shield" when he MIG welds - obviously this may be against what the Dr recommends and may not be safe.......

I've some experience in the testing of electronic devices for EMI compliance. There are different standards for different classes of device - ie kids toy v's electric wheelchair v's pacemaker. For devices needing a degree of immunity from EMI the tests involve pointing an antenna at the device and irradiating it with different levels and frequencies of RF radiation. How this level of RF compares with that emitted by a TIG I don't know. I'd be more worried about the high magnetic fields around a spotwelder.

Similar precautions apply to working on car engines and possibly other activities generating electromagnetic fields. I have always been interested in the effect of amateur radio on pacemakers. The research I did, some with help of pacemaker company representatives, was rather inconclusive. Personally I would avoid a ham shack in operation having seen RF sparks on metal objects otherwise not connected to anything, light bulbs connected to a piece of wire lit up by a KW with a key down, neighbours' lamps turned on and off and many other amusing phenomena.

The message I think is that you *can* have problems while arc welding, be it a St. Jude, Medtronics or any of the others. One problem not mentioned is re-programming the pacemaker which may enter the back up mode and not revert when the EM field is gone. Some may not notice it, some may become symptomatic.

A similar situation arises during surgery when the surgeon uses electro-cautery to stop bleeding. The usual procedure in this region is to convert the pacemaker pre-operatively to a fixed output that cannot be inhibited and crank up the voltage. The pacemaker is checked and reprogrammed carefully back to the original settings after the surgery. This is clearly not an option while welding :-)

Oh, and I would not expect a discussion with your MD to provide any more information than what is in the article. Unless he works in a major centre and does nothing but pacemakers. Even then I have my doubts...

Its not anything to do with a St Jude device or not. Modern devices have all the sensing done at the tip of the "bipolar" leads. Instead of an antenna 12 inches long it will be 1/2 long. Bipolar leads are made by all implant companies, Medtronics, Guidant, Biotronik etc etc. Sometimes a older style monopolar lead may be used as they are usually thinner ( they only incorporate one wire as opposed to 2 in bipolar). John

Does anyone have any insight into the relative impact differences between a rc welding (MIG or stick, possibly others) and plasma arc welding, like TIG ? I know that at some level, they are both an arc, but one is MUCH more of a nasty high-current crackling electrical arc than the other. TIG seems t o be a very minimal electrical arc compared to MIG.

Also, could a weldor (one who welds, as opposed to the welder, which is the machine that the weldor uses) wear some kind of a EMI shield, like a farad ay cage shirt, for example? Like this:

Do a little research on the rec.crafts.metalworking newsgroup . One of the regulars there did a lot of research when he got - I forget if it was a pacemaker or defib device - and he posted his results there .

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Snag