Anyone ever seen a LP12 do this before?

[fiznat]

Printed really thick lines. This was just for this patient. The previous patient and the next printed normally.

[Dustdevil]

Looks like 60 cycle to me.

[FireMedic65]

^^^ what he said

[EMS49393]

Exactly. I haven't seen that in years.

[fiznat]

Interesting. I remember hearing about 60 cycle interference in medic school, but not much about what kinds of situations causes it and how it can be avoided. This was a patient laying down on the living room floor with not too many other lights/equipment on, not sure what could have caused this. Anyone have more information about this phenomenon?

[Dustdevil]

Wow... you guys really haven't seen it before? I know it's a lot less common on the current generation of monitors than it used to be, but I still got it often on the LP12. If you're not seeing it, you must be hauling all your patients out to the ambulance before putting them on the monitor, because it's very common inside the house.

It's not actually a thick line. It is a baseline that is spiking about a millimetre sixty times per second, creating the appearance of a broad, thick line. Looking closely, you can see the individual spikes and count them. Finding the source is through the process of elimination. Turning off lights and unplugging appliances until it goes away. Sometimes you never figure it out. But it is always related to AC current, and can even happen in your ambulance if you're using the inverter.

[HERBIE1]

I haven't seen this since the LP 5's. Classic picture is alot more defined but I agree it's 60cycle interference. A good way to confirm this is to change the leads and see if a better picture emerges. If the problem occurred and then resolved on it's own, you need to ask what changed in the environment. A new piece of equipment was turned on, the telemetry radio, the inverter kicked in, etc.

If not, then I would suggest there could be an internal problem with the LP12 itself.

I would take that monitor out of service and have it checked out ASAP before it malfunctions in a critical situation.

\\Another thought- verify the leads are OK- no breaks in the wires, good contact with the electrodes, etc

Edited September 29, 2009 by HERBIE1

[AnthonyM83]

Well, picture won't load, but I have seen the thick lines you're describing.

I've only once had someone recognize it as 60-second interference, though.

It was mentioned in our EKG part of course, but never explained. Had to look it up.

[fiznat]

Well, picture won't load, but I have seen the thick lines you're describing.

I've only once had someone recognize it as 60-second interference, though.

It was mentioned in our EKG part of course, but never explained. Had to look it up.

Hit refresh a few times. The image embedding on this forum software is a little screwy, but usually I can see it after a refresh or two. If not, here is a direct link: http://www.fiznat.com/photos/ECG/thickasystole.jpg

Wow... you guys really haven't seen it before? I know it's a lot less common on the current generation of monitors than it used to be, but I still got it often on the LP12. If you're not seeing it, you must be hauling all your patients out to the ambulance before putting them on the monitor, because it's very common inside the house.

Heh now that you mention it I don't routinely put patients on the monitor inside the house unless there is an obvious clinical reason to do so. I find it causes more problems than it solves with wires getting tangled etc etc. I'm more of a "lets get going and I'll do things on the way" kind of medic I suppose. Maybe if I were otherwise I would see this more...? hm.

Edited September 30, 2009 by fiznat

[1EMT-P]

I have to agree with Dustdevil, it appears to be 60 cycle interference.... 60 cycle interference was common back in the day when we used LP 5's.