[BARC-List] CB sign on Divinity Ave, Cambridge (Harvard U)

[wm0g at comcast.net]

The EKG unit should probably be plugged into an isolation transformer in order 
to alleviate that situation. Most medical electronic equipment that is patient 
connected MUST be isolated from the patient per UL-544. 

Jack - WM0G


> Any number of ways. EKG signals are millivolts. If the 3 lead monitor is like 
> powered, there could be ground loops (possibly through stray capacitances). If 
> battery powered, it could be acting as an antenna.
> Older versions could have fairly low or non-linear input impedances which 
could 
> cause artifacts.
> 
> -John
> 
> Derek Scuteri wrote:
> 
> > Regarding interference with EKG machines,
> >
> > Patient with a 3 lead heart monitor on, now doctor orders EKG, placed EKG 
> leads
> > on, patient fairly still, notice "artifact" on the scope, try to 
troubleshoot 
> to get clean
> > non-wavy display prior to printing, not being successful, fellow workmate 
says
> > the 3 lead heart monitor sometimes causes interference, the 3 lead monitor 
is
> > temporarily disconnected, to my amazement "artifact" is gone.  How could a
> > 3 lead heart monitor, which I though passively senses/receives signals from
> > the body (neurologically speaking lets say action potentials ) cause 
> inteference?
> >
> > Derek Scuteri
> > Emergency Department Technician, EMT-B
> >
> 
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