Re: A dangerous thing?

To: tesla-at-pupman-dot-com
Subject: Re: A dangerous thing?
From: Mark Finnis <mefinnis-at-medicine.adelaide.edu.au> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Fri, 14 May 1999 22:14:45 -0600
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme
At 20:52 13/05/99 -0600, Terry Fritz wrote:

>	I don't mean to be morbid in our usually upbeat group but once in a while
>we need to stop and remember.  Ours is a VERY dangerous hobby!  Below are
>the brief accounts of the three people (that I am aware of) who have been
>killed...

... SNIP ...

>It should be noted that the last two of these incidents may have gone
>unnoticed if it were not for the Internet.  The possibility of there being
>others that we don't know about is very high.

Yes, I too was killed once, but I didn't tell anyone ;-)

But seriously, Terry is quite right.  Many coilers are not in groups and
unless the incident is non-fatal (such as the recent episode of Cabbott's
finger) it is more likely *not* to be reported.

There is just no gain in the fancy "stage stunts".  You can have plenty of
fun with HV without exposing yourself to obvious risk.  I see plenty death,
misery and sorry in my work ........ I don't want to hear about it on the
weekend when I'm relaxing !

The comments about RF not inducing VT/VF and death are **relatively**
correct.  The propensity to induce VF depends upon:

1.  the current passing through the heart (skin resistance and current
path), both of which vary (determined in part by Volts)

2.  frequency, viz.

Current to induce VF
  ^
  |                                                           *
  |                                                     *
  |                                               *
  |                                           *
  |                                       *
  |                                   *
  |  *                            *
  |    *                     *
  |        *            *
  |_______*_________________________________>  increasing F

	.... and YES, the nadir *is* at 50-60 Hz

3.  duration to a variable extent.

4.  The individuals predisposition to cardiac arrhythmia.  A significant
proportion of the population have an anomalous pathway between atria and
ventricles and are at **far greater** risk of induced arrhythmia.  Problem
is, you don't know until you get it !!
___________________________

Now, you don't need to be Einstein to work out from the above, one man's
cute HV demo is another man's demise.

Remember the safety FAQ document <http://www.pupman-dot-com/safety.htm> for
those few who haven't read this it should be considered mandatory.

Now, IF you are still going to perform the highly dangerous, remember to
NEVER work alone and to have your "mates" well trained in CPR.  But then as
we heard from Terry's post, this doesn't always guarantee a good outcome.

cheers

mark

..... from the "Halls of Endless Sorrow"



___________________________________________________________

Mark Finnis			Hm:  61 8 82895205
Staff Specialist			Wk:  61 8 82224000
Intensive Care Unit			Fax:  61 8 82236340
Royal Adelaide Hospital		Mbl:  041 23242268
www.health.adelaide.edu.au/icu
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