Accuracy/reliability - Manual BP vs. Automated.

[NYMedic828]

I've had this debate with a couple of people by now.

As an EMT, always had to go manual because I didn't have the monitor at my disposal but now as a medic I find it is more reliable, convenient and practical to use the monitor.

For starters, if I'm alone in the back doing 3 things, I don't feel its a viable use of time to take a manual BP when I can have the machine take care of it for me.

Sometimes, no matter how good you may be auscultating a BP may be impossible or not fully accurate due to what you may think you hear.

Its more convenient no question there. The monitor records a spreadsheet of all my vital signs for me to copy to my report afterwards and all that good stuff. Its less overall equipment I need to pull out. (always have a manual cuff in case though)

In 2012, with a brand new MRX monitor I would think the technology has come pretty far in regards to accuracy.

I very rarely see anyone in a hospital whip out a manual BP cuff, so it must be acceptable to the medical world at large to use a machine.

Thoughts?

 

[Aprz]

We've had discussions on this before.

I think that if you do it by machine only, if the blood pressure is consistent with the rest of your assessment, it's okay.

You could do a manual to verify that the machine is correct, but even if you get two different blood pressures, that doesn't automatically mean the machine is wrong, the manual blood pressure could be wrong (e.g. you hear nothing, you hear the stethoscope tubing bumping and mistaken it to be the systolic or diastolic).

As one of the actual useful Ayn Rand quotes from Atlas Shrugged goes, “Contradictions do not exist. Whenever you think that you are facing a contradiction, check your premises. You will find that one of them is wrong.” We need to troubleshoot both the test itself as well as our assessment. Did I miss something? Is there some preexisting condition that I’m missing? Am I assuming that there is only one new condition?

4 Phrases That Should Never Be Said on an Ambulance

If you want to do it manually only, that's okay too. I wouldn't say that manual is more accurate than by machine; I'd consider it to be a preference, the machine isn't working (e.g. won't turn on), or you don't have a machine.

 

[EpiEMS]

Can't help but wonder if a machine would hold up better in, say, court, or at a hearing.

 

[MedicBender]

I try to grab a manual on scene. If my monitor shows a drastic change en route or my patient presentation changes I reassess and try to grab another manual. On occasion I've got to much to worry about. We only send one truck to a call so sometimes I have to settle for an automated while I do all my other things.

For the most part my LP12 is pretty damn accurate. On occasion it does give me some crazy numbers though.

 

[Aprz]

Is there some sort of precedent from an actual court case that manual is better than by machine? I have my doubts since it seems to be the standard for various disciplines.

 

[Handsome Robb]

Can't help but wonder if a machine would hold up better in, say, court, or at a hearing.

Have you spent much time in the ER or on the floor? Its nearly if not completely 100% automated BPs. I doubt use of an automated BP, especially if it's approved by the FDA and your company, would be the single deciding factor in a court case.

For the most part my LP12 is pretty damn accurate. On occasion it does give me some crazy numbers though.

Per protocol we are supposed to get a manual first and generally do, especially if the FD is on scene. After that it's all automated. We use the MRx but like you said it's generally pretty accurate but occasionally throws out wacko numbers. Generally it's kinked tubing, poor cuff placement/fitting or the pt moving around or using the arm it's taking the pressure on. All easily fixable.

 

[sir.shocksalot]

Can't help but wonder if a machine would hold up better in, say, court, or at a hearing.

Interesting argument. I had never even considered this angle. Personally I believe that the machine is more reliable than a person. That being said, I have noticed that any amount of artifact for the NIBP tends to skew the results wildly, if the patient is moving or the ambulance is bumping down the road you may get an inaccurate reading. With this in mind I think the NIBP is quite safe to use to determine a BP.

I still think one of the funniest things I have heard paramedics say is "Don't use the BP on the monitor, it isn't accurate." All I can think is "I have never once seen an RN or MD/DO take a BP in the hospital with a manual cuff, what do we do as paramedics that dictates that our BP's have to be more "accurate" than that of a physician or a nurse". If it's good enough for a doc to use then it's good enough for me.

 

[Veneficus]

I've had this debate with a couple of people by now.

As an EMT, always had to go manual because I didn't have the monitor at my disposal but now as a medic I find it is more reliable, convenient and practical to use the monitor.

For starters, if I'm alone in the back doing 3 things, I don't feel its a viable use of time to take a manual BP when I can have the machine take care of it for me.

Sometimes, no matter how good you may be auscultating a BP may be impossible or not fully accurate due to what you may think you hear.

Its more convenient no question there. The monitor records a spreadsheet of all my vital signs for me to copy to my report afterwards and all that good stuff. Its less overall equipment I need to pull out. (always have a manual cuff in case though)

In 2012, with a brand new MRX monitor I would think the technology has come pretty far in regards to accuracy.

I very rarely see anyone in a hospital whip out a manual BP cuff, so it must be acceptable to the medical world at large to use a machine.

Thoughts?

Sounds good to me.

Not a bad idea to have a manual available though in case you get a reading you don't expect.

That allows you to basically field check the machine.

The machines are very accurate now-a-days, but if there is an accuracy question it is likely to be at a low BP, not a normal or elevated one. Which if permissive hypotension or any treatment that is BP sensitive is your plan, the manual cuff may come in handy.

Edit:

I still think one of the funniest things I have heard paramedics say is "Don't use the BP on the monitor, it isn't accurate." All I can think is "I have never once seen an RN or MD/DO take a BP in the hospital with a manual cuff, what do we do as paramedics that dictates that our BP's have to be more "accurate" than that of a physician or a nurse". If it's good enough for a doc to use then it's good enough for me.

Actually we do if there is a wild reading or the bp is too low for the NIBP prior to invasive monitoring.

 

[thegreypilgrim]

Generally I agree that the NIBP is a better option due to convenience and accuracy is probably better than manual sphygmomanometers since they're rarely calibrated or maintained properly.

The only problem with them in my experience is their accuracy tends to drop off once the patient becomes hypotensive. But then again, the only automated BP I've ever had to deal with is the one on the Zoll M Series - perhaps the most poorly constructed monitor of all time. Now I have an LP12, but unfortunately we don't have automatic cuffs for them.

I've never worked with the MRx so I can't really say one way or another.

 

[EpiEMS]

I should've been clearer in my last post - I would think that an "infallible" machine's reading would hold up better in court than a manual pressure. It does seem to be the standard within hospitals. Granted, I almost always take a manual pressure first (except when I'm with one medic who just moves straight to the auto cuff), but that's largely because it's protocol for us.

 

[RustyShackleford]

I think it depends on your personal machine and how it functions. I always found the LP-15 was pretty on par with manual readings, now I have to use a Zoll and its less than reliable.

 

[SwampLifeEMT]

I Agree

Being in the back of a box helping a patient can and is a very stressful position. I feel the same as most people I do not want to be doing manual BPs Unless I have to. Trying to stay still enough and quiet enough to take a manual BP is a handfull in its self. When your partner is a crazy driver and whips the box like its a fraking 240 at a drift competition adds to the reason why the LifePak is such a better way to take BPs and vitals in general.

 

[OSMedic]

I will always take a manual BP initially to get a baseline for my patient. If I have a long transport time I will use my LP12 BP after the initial manual BP. That way I know if the automated one is giving me some crazy number.

 

[the_negro_puppy]

We use Lifepak 12s here and pretty much always use automated BPs. I take a manual if I have reason to doubt the automated reading

 

[usalsfyre]

I will always take a manual BP initially to get a baseline for my patient. If I have a long transport time I will use my LP12 BP after the initial manual BP. That way I know if the automated one is giving me some crazy number.

How can you be sure the automated BP is the wrong one?

 

[NYMedic828]

How can you be sure the automated BP is the wrong one?

Thats what I always figured.

You technically can't.

My feeling here is, as long as everything is done proper, the machine has less room for error than a human.


Also, one big issue with the machines is an improper cuff size. You really can't just make a huge cuff fit a little arm or vice-versa.

 

[Aprz]

Using the correct cuff size is just as important when taking a manual blood pressure too.

 

[Akulahawk]

My usual MO is/was to take a manual BP (or have someone I trust take one) when I got on scene and as time permits, switch to auto - if available. If the two are in the same ballpark, I will continue using the auto BP for trending info. If they're not, I'll trust my own ears and stick with manual BP. I can get the BP faster than the auto machines can... unless the machine is getting it's data from an a-line...

Now all that being said, I prefer to give that task to someone/something else so that I can get on to doing other things, but I'm not above doing it myself.

 

[usalsfyre]

Am I the only one who has seen denial be a huge issue with manual B/Ps?

 

[EpiEMS]

Am I the only one who has seen denial be a huge issue with manual B/Ps?

Denial? As in "Oh, I got ###/##, that can't be right."?