Manual BPs (question about sphygmometer)

[Para-Medic]

Hi all,

I always wondered on why sometimes the needle on the sphygmometer will move before and/or after hearing the beat? The reason I ask is because sometimes (not always) I will see the needle move and later hear the beat. Well, curious on whether I got it right or not I test it again in the hospital with their machines. I notice sometimes the monitor will show the B/P to be basically where the needle would be moving and not exactly to where I heard the beat. I know their B/P might of changed a bit, but sometimes the machine will say I was about 5-10 off (pretty much where the needle started moving). Still though, I wonder if the needle would be sensing something earlier than we would in auscultating. I know the rule on not using the needles movement as a guide just the auscultation, but wouldn't it be something to be taking into consideration. Obviously, I'm not any medical expert on this and don't know much. Still, I'm just curious on what it could mean. If anyone has any input on this please post. THANKS

[AZCEP]

The needle starts jumping when the cuff pressure is at, or below, the arterial pressure. You won't hear the pulse until the cuff is well below the arterial pressure. Use the needle bounce to give you an idea of when you should listen a bit closer. The pulse should start pounding in your ears relatively quickly after the needle moves.

[Ridryder 911]

Never trust the needle on the dial "jumping" as a sign of a BP. The arterial pulsation can give a false reading. The cut off value when you hear the korotkoff sound ..Most EMT's are not aware of the 4 sounds of a blood pressure. Pump the cuff usually 20 points above the last hearing of the pulsation.

Palpations of blood pressure is not an accurate finding,but commonly used for systolic finding.

Nothing irritates me more than someone that reports a BP in odd numbers, using a manual cuff ! :twisted:

Be safe,

R/R 911

[Michael]

Rid's reply sent me to this informative description: http://en.wikipedia.org/wiki/Korotkoff_sounds

[Nate]

I thought the machines use the pulsations they feel (needle tick) to get their version of the BP?

I trust my own ears over any machine any day, however I can't tell you the last time I saw someone out side of EMS (flight or ground) or the ER use a manual BP cuff.

[Para-Medic]

I thought the machines use the pulsations they feel (needle tick) to get their version of the BP?

I trust my own ears over any machine any day, however I can't tell you the last time I saw someone out side of EMS (flight or ground) or the ER use a manual BP cuff.

That's exactly what I was always thinking. I mean, of course a person would trust what they heard when taking a B/P rather than letting a machine do it and not being able to verify if it's right. So, with that in mind, why would doctors and nurses allow the machine to do this and allow these readings to determine what meds/interventions to take? Seeing as how the machine use pulsations to get a B/P and a manual B/P (which is suppose to be more accurate) involved auscultation.

The main reason I ask this is because I remember I was dropping off a patient (c.c. was she couldn't stop vomiting) and when we got to the ER they had to take their vitals (using the machine of course). So I thought ok I got stable vitals the whole way here so it should be fine. Suddenly their machine reads 90/56 and they were going to start a line on her. I thought, that can't be right. So I repositioned her arm placed the cuff firmly on and tada 110/88. Took it again and got the same thing. So basically, I'm just questioning the reliability of these machines.

[Dustdevil]

If you are a competent medical professional, and there is some question as to the reliability of your auscultated BP, you know it. You KNOW you aren't positive about what you heard. You don't have that luxury with a machine. So even if your auscultated BP is questionable, you still get vastly more information from it than you do from a machine.

Screw those machines. Save the money and put it in my benefits package instead.

[Ridryder 911]

Dust you would hate most ER's now.. In our 20 bed (acute side), we only have 4 manual B/P cuffs & they are located on the crash cart. I spec the equipment for the rooms, each room has a electronic B/P , with (continuous 15 lead, if you want) EKG, SpO2 & side stream EtC02 as well.... of course you can't forget telephone, cable t.v. as well.. LOL I finally have most of the new nurses understand, if you have a questionable BP to get a manual. OF course there are dopplers on each cart as well. So far at least >90% of the time they are within the ranges, when tested against manual.

For as costs. you can add BP to LP 12 or other monitors for small nominal fee...not enough that would change budget concerns for benefits, but I do understand your statement. But, on those critical care transports with q 5-15 min v.s., 3 IV's infusing, plus blood, and ventilator ... it makes it nice.... you can print out, in the end.. I routine spot check... as I encourage students to do the same. Like in the unit, you should periodically routinely auscultate a B/P, unless they have an art line in...

Like I said it is like any other diagnostic equipment. you need to have multiple sources and use clinical judgment...

Be safe,

R/R 911

[Para-Medic]

Just had an idea. What about if these machines had some sort of output that allowed you to hear it when the machine is taking the B/P. As the machine starts to lower the air pressure you would have a visual on the numbers (most already do). Anyways, as the machine starts to deflate the cuff you could listen for the proper sounds. This way you could have some security on what you heard. When the machine gets the reading you could compare what you got to what the machine got. If there is any suspicion you could continue to take a manual B/P.

One other thing I notice is when the machine takes a low B/P or high B/P none of the nurses or doctors bother to take one manually. They automatically start to take give meds for something that could of been an error. : S

[Burnzonemt]

The other week we transported a pt. who I would guess to have weighed at least 400lbs. Needless to say our lifepak12 cuff didn't fit on his arm. So I dug out the LARGE adult (read thigh) cuff and went for a manual bp. Sounded like I heard a sys of 130. The other emt also took it. Neither he nor I told the other what we got until after we were both done. He came up with140/90. Sounds good to me, so we get him to the hospital and they use their machine only on the forearm. They obtained a pressure of 168. I thought WTF, I'll put that in my bag of tricks and try it the next time the cuff doesn't fit. On the ride back to the station I took my bp on the machine first on the forearm then on the upper part of the arm. The difference was almost 40 points. I got rid of that idea real fast. I still insist on having at least the first reading done manually. I prefer manual done all the way, but sometimes I don't have a choice when another EMT techs the call. I will admit to using the machine once in a while when I'm filling out paperwork or maybe feeling lazy. It scares me tho if my partner, or any emt for that matter cannot get a manual reading on any pt.

Just my 2 cents.