Measuring blood pressure


  • Specializes in Gerontology, nursing education.

I had something very bizarre happen today at a clinic but I wanted to check with others on AN in case I might be incorrect on this.

A CNA checked my blood pressure. I was wearing a long-sleeved shirt that was a bit tight in the sleeves so I could not easily roll up my sleeves. The CNA said not to bother trying to roll up my sleeves and, instead, she took my BP on the LOWER part of my arm. The reading was way off and she used one of those d*mned automatic cuffs so it inflated very high and actually HURT when she was doing it.

WTH? I've been an RN (first ADN, then BSN) for nearly thirty years. I've done blood pressure checks as a parish nurse. I've been a clinical instructor and taught skills lab. Never, ever, EVER have I seen or taught ANYONE that it's appropriate to check BP on the forearm. Always, always, ALWAYS have used the upper arm and cannot imagine why this CNA would have done this---unless she either had no idea what the heck she was doing or if there's been some changes in acceptable practice of checking BP of which I am unaware.

Is there a new procedure of which I am unaware? A new way that is acceptable for people to check BP? I am thinking not, that this CNA clearly has no clue of what she is doing, but I wanted to check with the folks here on AN to make sure. I am very polite to people and don't believe in going off on a stranger---so I generally don't say anything about mediocre or poor customer service unless there is REALLY a problem. I was also taken aback that I was actually speechless! I mean, yes I would have said something to a student or an orientee who made a similar mistake but I didn't feel like trying to correct this total stranger. I also don't believe in being a PITA patient and telling everyone that I'm an RN, yadda yadda, so as to intimidate someone or make them feel nervous around me.

Good grief---and to make it worse, she asked me how my drive was and when I told her that I got stuck behind some farmers doing harvest, she prattled on and ON about having been in an auto accident with a tractor years ago. Yeah, that story was enough to make my pressure go up, too. Of course her story got me upset. Duh!

So---unless there is something that I don't know and this CNA was doing it right, I am going to call tomorrow to speak with her nursing supervisor. Oh, and she had the guts to say that maybe she should check it again before I left. NO THANK YOU!

Dang---my arm is still a little sore. She really hurt me. :angryfire

Input welcome. Thanks!


1,459 Posts

On the lower rm, you said?Hmm,I just got out of Nursing school ot too long ago and we weren't taught that. Let's see what others have to say.

Specializes in Emergency, Case Management, Informatics. Has 13 years experience.

I've done it maybe 3 times in the 3 years I've been a nurse, but only when I was working in a situation where I didn't have the right equipment available in my workplace (only a regular cuff available and the patient was extremely large).

It can be done, but it's difficult, and definitely not a first choice for BP. Here is a link detailing a study of accuracy between upper arm and forearm BP's. The study showed that forearm BP was on average 4 points systolic and 2.3 points diastolic higher than the upper arm BP. If I had no other option, that deviation is acceptable to me.

Definitely wouldn't do it with an automatic BP cuff, though.

Also, the CNA could have done the BP in your upper arm without rolling up your sleeves. It's not really necessary for a routine check, as long as you have a halfway decent stethoscope.


8 Posts

I am in nursing school now and have been told that this was acceptable. While learning VS, I wanted to practice on my husband (who has very large arms and won't fit my regular sized cuff) and my nursing instructor told me to check it this way and use the radial pulse. I have never done this with an automatic cuff though.

netglow, ASN, RN

4,412 Posts

Nope. If arms are not an option, there's thigh. but that reading will also need adjustment.

nursemike, ASN, RN

1 Article; 2,362 Posts

Specializes in Rodeo Nursing (Neuro). Has 12 years experience.

The aides where I work routinely use automated machines for routine BPs, and will take them in just about any convenient extremity. Sometimes the upper arm is just not practical. Sometimes no part of either arm is. Most of the aides are good about using the same site, each time, so I can at least track trends. I look on these as estimated BPs, but if they're good, that's usually close enough. If a charted 125/80 is actually 130/75, it probably won't alter anything I'll be doing. If it's 165/85, I'll ask them to recheck it manually. If it's 175/90, I'll be checking it myself, manually, as soon as I can track down a manual cuff.

A couple of our machines are new, and the other was recalibrated not long ago. They generally correlate pretty well with a manual reading, with a few exceptions. Before the old one was serviced, I could estimate BP as accurately by visualization while standing in the doorway. It's a lot better, being able to trust your equipment, but I still only trust it so far.


246 Posts

I have never been taught to do this, and I am fresh out of school, but when I was a tech I once saw a charge nurse do it on a very large patient, with an automatic cuff. I am not sure if she knew how to modify the reading or not. Often if nursing support does something like this, I think they may have seen someone else do it, and they just followed along. Perhaps someone who oriented them, someone else in the office that may be experienced and that they look up to professionally, etc. Of course if this is not appropriate practice, they should be educated.

Chaya, ASN, RN

932 Posts

Specializes in Rehab, Med Surg, Home Care. Has 15 years experience.

Have seen some of the home machines used on the forearm. Also, we will not infrequently see a situation where neither arm is ideal for BP,ie; CVA with one-sided weakness and PICC in other arm, or IV directly in AC. Then we get the pressure wherever we can-forearm or leg, what seems to matter most is consistency in using the same site each time so we can tell if the BP remains stable.


110 Posts

Yes you can take a blood pressure like that it is often done on larger patients when you cannot find a larger cuff You just listen at the radial artery instead of the brachial. I was taught that in nursing school. You can take a pressure anywhere you can occlude an artery. (Thigh, forarm, leg, ect) It is just easier to use the brachial.

mamamerlee, LPN

949 Posts

Specializes in home health, dialysis, others. Has 35 years experience.

Wrist/forearm cuffs are very popular in home health and certain other settings. I used one when I worked at a jail, too, for my own safety. I take my own BP at least 2 times/day with a wrist cuff, best readings are when the cuff is near the level of the heart. The key here is consistency.


65 Posts

Specializes in Telemetry/Med-Surg.

We do occasionally use the lower arm for obtaining vital signs, so she was not wrong to do this. Our documentation screen at my hospital even has a selection for lower arm when we put our v/s in the computer. This just goes to show you can learn something nrw everyday.


72 Posts

Specializes in mostly PACU. Has 13 years experience.

Yes you can take the BP in the forearm. It was done all the time in the PACU when we didn't have any extra large cuffs for morbidly obese patients. They also do it in the OR sometimes. It's the same thing as doing a BP on someone's leg with a thigh cuff. The readings may be different for various reasons, and sometimes they are the same.