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612551 tn?1450025775

Uses of Pulse Oximeter in Rhythm Monitoring

Most (all?) of you have seen the small clip-on-the-finger over a finger nail used in doctor offices to measure the Oxygen Saturation level in your blood (target 95% or better I believe).  These doctors don't have a pulse display on their units or simply prefer the manual method to measure pulse rate, which both the nurse and doctor do, the doctor of course also listens to my heart with a stethoscope.

It is difficult for me to feel my pulse (a blessing in many respects) and I have for years used a stethoscope to count my pulses, heart rate.  The only indication I have of the blood oxygen saturation is if I am dizzy or breathless more than what I recall as normal.  I have thought that it would be helpful to be able to measure the O2 level at those times and even to run a DIY sleep test (this in general would require a recording meter).

When I saw this type instrument with a combined HR and O2 plus a pulse intensity readout for under $25 delivered I ordered one.

Here's what I learned for my profile and what I have concluded about a number of aspects of my AFib condition on my physical being.  I compared/checked the device HR by counting my HR while using the clip on, good agreement.  I checked my wife who does not have any diagnosed heart conditions and found reaso6 nable readings and a smoother more uniform heart intensity readout than I got for myself with AFib.. as expected.  I take the intensity differences between her and me indicative, not quantitative even though it is provided via a 6 bar readout scale.  

I found my O2 consistently obove 95% even when I was feeling O2 starved, like when standing up quickly.  I also found my HR reasonable and in the 70s when resting and typically around 100 when in light physical activity.  

Now for sleeping, or really maximum rested times.  

I did not get a recording meter for $25, but as I wake up often during the night it is easy for me to clip the device on with minimum physical effort when I wake up.  Some interesting findings (to me) - I am on a normal release Metoprolol (BB) and Calcium CB which is taken at about 10:30 PM, so by 1:30 AM I am still in the fully medicated area of the BB concentration (half life of 4 hours assumed).  

Early in the morning (around 2 AM) I found my fully relaxed in bed HR as low as upper 50s and O2 levels as low as 90%.  Later in the morning (around 5 or 6 AM) I found my HR around 70, suggesting the BB had lost a considerable % of its strength (now in its 2nd half live, about 75% metabolized) and the O2 levels over 95%.  This seems reasonable and in fact during the day my seated and fully resting HR runs in the 70s to 80s.    The lower O2 level of 90%, which is the threshold of trouble as I understand, at 2 AM is a minor concern to me.  This many not be a trouble indicator under the condition of being under BB and CCB near full strength and just in/out of sleep resting state.  I continue to check and see if my results are consistent/repeated.

In any case I find having this testing device affordable and quick way to check my HR, and also get the O2 saturation  -  the value of the heart intensity readout is not clear, but does give me some concern... guess it is the variations I hear with the stethoscope.

35 Responses
187666 tn?1331176945
Sounds interesting. I don't worry much about my O2 except when my asthma flares up. Then I use my peak flow meter to see how my lungs are working. I have a strong pulse so I can check rate any time: either wrist or carotid.

I'm being stupid here but what is "heart intensity?"
612551 tn?1450025775
The device I have has a 7bar element stacked vertically (so to speak) and this stack of bars is triggered by each ventricle beat.  In my case the the number of bars seldom exceeds 4 bars.  Using the device to check my wife numbers more pulses went the full 7 bars... best I can recall at the moment.  I simply check on her finger to see what a healthy heart would register.  The "intensity" display was very regular and strong.  No so in my case.  On the other hand my O2 was as good or better and her resting HR was in the 80s, higher than mine, mine being held down with beta and calcium channel blockers.

My cardiologist has agreed with my request to change my Metoprolol to Atenolol which I learned in another thread has a longer half life (slower release for regular non-SR tablets) and had a lower penetration.  I have read other "good things" about Atenolol.  I'll see if I have more steady HR (it is very easy to check now and I will confirm while still on Metoprolol that my sleepy rest rate changes significantly between 2 AM and 6 AM, given my sleeping problems Im sure I'll be awake.  As noted, last night I saw a HR much lower at 2 AM about 3 hours into the BB dose run down, to the HR at 6 AM 7 hours into the BB dose run down.  Then too, if the change in BB lets me sleep more restfully I may not be waking up at these wee hours times.
995271 tn?1463927859
I have one of those as-well!  very cool to get a better understanding.  Your resting pulse is excellent for having afib.  So is you O2 sat.  the variance you are seeing at night could also be due to your own natural circadian rhythm.  I'm not medicated at all, and I find that my average HR varies throughout the night.  IN the wee hours, respiration slows down greatly which to me would have the greatest affect on o2 sat.

anything > 90 is fine.
995271 tn?1463927859
p.s., O2 sat is a lot more affected by respiration then HR, in my humble opinion.  For instance, when I was on top of pikes peak my heart rate didn't change and I didn't feel short of breath, but I was dizzy at times and that's from low 02 sat.
612551 tn?1450025775
I have in recent years chronic nasal congestion, but almost only when lying down, as in bed time.  While I can breath through my mount, and dry mouth in the night says I'm doing that more than I'd like, it is better to breath through the nose.  

The congestion sometimes causes me to feel like I am suffocating...mental? many be.  This is another condition driving my interest in the O2 sat level.  

I took my 25 mg BB about an hour ago, so I assume my BB level is near maximum and my resting HR (sitting in front of my computer and TV) is about 80.  It will be interesting to see if it drops again into the upper 50s in the early hours, just after waking up form a couple of hours of sleep.

I'll be on Metoprolol for my BB for another 10 days or so.  I plan to use up the pills I have before changing to the new brand I requested.  My cardiologist is likely just humoring me by agreeing to my request to try a different BB.  He had been reluctant in the past saying why change anything you are doing well.. and I say I'd like to do better.  I have read not all BB are equal, they are somehow different, including the half life on concentration in the blood, and in how "selective" they are in not affecting the brain operations.
187666 tn?1331176945
Thanks for the explanation on "intensity." So more bars is higher intensity which is a good thing. Palpitations which feel like a pounding heart seem like a bad thing. I wonder if they register on the meter.

Then lower bars mean the heart isn't beating as effectively as it should.

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