Am I missing something here?

Specialties Emergency

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two recent incidents make me question some stuff.

1. a friend who is a new grad being oriented into the icu of a cardiac center seems to be given bad information. she uses a 5 electrode system, and believes the the brown electrode is a ground, and can be put anywhere on the chest. i explained that the brown electrode is more likely a v lead, and can be placed in a number of positions, the most common being v1-v6. i explained a couple of reasons one might want to choose where to monitor. she seems a little skeptical, as she is being precepted by one of the more experienced nurses there, and what i explained to her seemed pretty basic.

i have seen this in the icu, where most of the nurses i worked with, put the brown electrode in a random spot, and only monitored the inferior heart through lead ii.

2. had a pt last night who's primary complaint was respiratory- no chest pain, but multiple risk factors. ekg showed depression in leads v5-6. so- i set the monitor up to monitor lead v6 as the primary lead. figured i might want to know if any treatment i gave resolved the ischemia. also figured if there was going to be any elevation, that might be a good place catch it. while i wasn't watching, somebody mpved my brown electrode to the middle of the chest-somewhere between and below v1-v2. (right at shift change i got a positive troponin)

am i missing something here? this can't be all that complicated, as i am not all that well educated or experienced. it seems rare that i encounter other nurses who know this stuff. why is that?

any thoughts?

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The brown lead goes where ever the equipment manual suggests. You can get crazy and rig stuff however. I have seen all kinds of colors go all kinds of places and remember doing modified nine leads with a three lead system of the old LP10's. I like your thinking; however, the problem being most of your "rhythm strip" monitoring is done in a non diagnostic mode where accurate information is nearly impossible to gather. You are truly monitoring a rhythm strip that is good for picking up blatantly obvious changes such as ventricular fibrillation.

The best thing to do is obtain a XII lead as a XII lead machine looks at the leads with diagnostic quality. However, some monitors allow you to change the filter settings to obtain a diagnostic quality strip.

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Specializes in med/surg and Tele.

Being a monitor tech and working the floor myself. I was trained to put the V-lead in the middle of the chest or by the sternum. I have never heard of putting the V-lead in any other place besides that. Not that i am saying that it is not possible but for a 5 lead its just something that I have never heard of before. If I am wrong then someone is more then welcome to correct me on this, but the proper placement of the V-lead should be in the middle of the chest preferably between the nipples.

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Being a monitor tech and working the floor myself. I was trained to put the V-lead in the middle of the chest or by the sternum. I have never heard of putting the V-lead in any other place besides that. Not that i am saying that it is not possible but for a 5 lead its just something that I have never heard of before. If I am wrong then someone is more then welcome to correct me on this, but the proper placement of the V-lead should be in the middle of the chest preferably between the nipples.

And from Gilarn The brown lead goes where ever the equipment manual suggests

This is what I am looking for. Is there any documentation anywhere suggesting the brown electrode goes in the middle of the chest, if so why? This is such a widespread practice, I figure it must come from somewhere. The other electrodes are all put in a specific spot for a particular reason. For example, the red allows a view of the inferior heart. If you aren't going to monitor the anterior or lateral heart, is there any particular reason to put brown on the chest at all? Why is it referred to as "the v lead"? In any other context we specify which v lead we are talking about.

Regarding accuracy of monitoring in monitor mode: I don't know how to go into diagnostic mode, neither does anybody I work with. I am not sure these particular monitors are configured in a way to allow it, though I am pretty sure they are capable. Even in monitor mode, you can see st segment depression vs elevation. I have watched re-perfusion on a monitor.

BTW- I frequently leave the monitor in the default of only monitoring lead II. It is convenient, and I am so used to seeing lead II that it is easy for me to pick up abnormalities. On one occasion, I had what looked very much like V-tach on my monitor. If I knew then what I know now, I would have just checked a couple of V-leads 1 and 6, and seen it was a bundle branch (rate dependent). Sure a 12 lead is best, but it takes a lot more time to get the machine and set it up than to hit a button on the monitor, and then switch one electrode.

I am not putting myself out as an expert. I fiind myself periodically being in a teaching position, and would like to guide people toward best practices. This one is so ingrained, I would like to know where it comes from before I tell people that what they have learned is wrong.

An article I found interesting:

http://ccn.aacnjournals.org/cgi/reprint/23/6/71.pdf

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Specializes in Cardiac Telemetry, ED.

I've only worked with the EASI system, in which the brown electrode goes at the bottom of the sternum. The green electrode is the ground and can go anywhere. But from what I do know of the basic five lead system, it sounds like you're on the right track.

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The changes you saw in V5-6 could of been recipocal changes. Did the pt end up having a posterior MI. That would explain the elevated troponin. If you do your own EKG's in the ER you can take V4 and put it on the right side of the chest where V3 would normally be if on the left side. Then take V5 and V6 and put them on the pt's back. V5 midclavicular and V6 inbetween 5 and the spine. When you print out the EKG V4,5,6 will be the posterior leads. Hope that helps

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Specializes in ED, CTSurg, IVTeam, Oncology.

Before the advent of 12 lead systems (with enough wires to wrap a Christmas Tree, LOL...) there were only four wires, the three limb leads and ONE movable V lead. The three bipolar (or negative to positive) limb leads stayed put, while the 12 lead EKG was done by moving the suction cup bulb V (or unipolar) lead from one horizontal point to another, running the ekg strip for a few beats, then stopping it again so that the V lead could be moved to the next recording point. In practical application the V lead is only theoretically considered unipolar; it is actually electrically bipolar, using the aggregate of the limb leads as its negative pole. Years ago, it was routine for a physician to also ask for a "V4R - V6R" to be included (to rule out RV infarct). This was easily accomplished as one simply had to move the single V lead to the other side of the chest and continue the recording for three additional leads.

Historically this "extra" lead is referred to as MCL1 (Modified Chest Lead, Marriott's Chest Lead, and Modified Central Lead) and is usually left in the same location as a normal V1. However, if you're looking for something in particular, then putting it into the spot that would be most sensitive to what you're looking for in certain clinical situations would also be appropriate.

Otherwise, the advantage of routinely placing that lead into where V1 sits (and this is why most recommendations show it there) are:

1. You can immediately distinguish between left ventricular ectopy (where QRS is mostly positive, and also has a greater propensity to give you R on T phenomenon..ie Ventricular Fibrillation) and right ventricular ectopy (where QRS is mostly negative) in most cases.

2. You can tell right bundle branch from left bundle branch.

3. P waves are more easily seen in right sided monitoring leads.

4. Most importantly monitoring in MCL1 gives you the information you need for the differential diagnosis between ventricular tachycardia and aberration.

The disadvantages of MCL1 is that it fails to recognize shifts of axis and the polarity of the p wave is not as informative as it is in lead II, (sinus p wave in MCL1 when it is diphasic is usually +-, and the ectopic or retrograde p wave is -+)

Source: http://rmccrory.tripod.com/intromcl1.html

So while placement into V1 is standard practice, placing it elsewhere to specifically look for something in particular is also clinically correct.
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