Sweat artifact filters for Sandman

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Sweat artifact filters for Sandman

Postby SuperTech67 » Wed Mar 16, 2011 6:12 am

Does anyone know what HFF filter to use to eliminate sweat artifact for sandman? I have done everything in room for pt, ac down to 64, fan blowing directly on him, grounds changed and moved to non hot area.
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Postby lil_miss_sleeptech » Wed Mar 16, 2011 6:57 am

Don't know Sandman settings specifically, but try a LFF of 1.0. (since sweat creates a low-frequency sway)

Also, if you have it available in your lab, try dabbing around the EEG electrodes with anti-perspirant. Or alcohol wipes.

Or just throw a bunch of ice on them :shock: :wink:
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Postby linuxgeek » Wed Mar 16, 2011 9:52 pm

Or collodian. :twisted:
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Filters for "sweat"

Postby nowhere » Sun Apr 03, 2011 11:27 pm

I wouldn't use anything more than a .5LFF...1Hz may alter the appearance of slower activity; I can tell right away when a tech changes filters, even if they don't acknowledge it. Obviously I also score... you really need a good grasp of the concept of filters before changing what's set in your montage; they're set that way for a reason.
Some of that "sweat" may really be respiratory artifact (compare resp. ch. w/sway). I've seen a lot of this go away w/ CPAP; if it's really resp artifact.
You can also flip the pt's pillow over, put a towel under their head to absorb some sweat and dab their head for excess moisture.
Sometimes that darn sweat will just not go away... If I score a study w/a lot of sway "sweat" and it's still readable and, the tech has tried everything possible I deal with it and hopefully, so will the interpreting Dr.
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Postby somnonaut » Mon Apr 04, 2011 12:30 am

Typically these "Filter changes" are non-destructive and only affect the viewable data, not the actual data. Make sure your techs are not changing the acquisition filters of whatever machine you are using, and whether or not they change it, is moot, as the data still has the information, and review of the recording "As recorded" can help ascertain the tech's usage of said filters or settings. All machines on the market who sell to AASM criteria must have a view as recorded feature.
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Postby Rocklandish » Tue Apr 05, 2011 5:59 am

Alright I used to have all kinds of trouble with Sway artifact on the Sandman systems. This is what I came up with.

Take a 4x4 and unfold it. Cover the bottom 2" with a thin layer of paste. Fold it over so that it is 2ply. Create and cut your EEG patches from this. This creates a sponge that draws sweat away from the electrode. Since doing this I rarely have trouble with sway on any system.
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Sweat artifact

Postby nowhere » Tue Apr 05, 2011 8:54 am

Oops, my bad... I forgot about the good old "display as acquired" button.
Yes, that does help. Actually I use that setting when I think something's been changed and doesn't look right for the channel.. and to get an actual picture of how the tech's looking at the study while acquiring if I have any other questions.
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Postby Rattlehead » Tue Aug 07, 2012 11:35 am

If it's a Sandman version that uses the SD32 amp, try using a can of air-duster on the cooling ports for the fan. The cooling fan inside the amp can get clogged with dust, causing some form of thermal issue inside the amp.

I went as far as to run a laptop cooling-device under the amp itself to help maintain airflow.

On the SD32's, there's a certain serial # range that are prone to failure. One was replaced under warranty during the Tyco days, it works fine. The other was not within the replacement range, and has been nothing but problems.
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Postby somnonaut » Wed Aug 08, 2012 3:18 am

Rocklandish wrote:Alright I used to have all kinds of trouble with Sway artifact on the Sandman systems. This is what I came up with.

Take a 4x4 and unfold it. Cover the bottom 2" with a thin layer of paste. Fold it over so that it is 2ply. Create and cut your EEG patches from this. This creates a sponge that draws sweat away from the electrode. Since doing this I rarely have trouble with sway on any system.


Not sure I follow you on this. How do you use the resultant "sponge" and why would it whick moisture, is it Antiphlogistine?
My uncle (a pediatrician) would use this stuff on us for everything.
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