[Product Review] Pulse Oximeter CMS 50E

[jdireton]

Pulse Oximeter CMS-50E
I've used this oximiter for about a month now.  I give it four stars for being basically outstanding but with some issues.  The data is easy to read and the O2 lows correspond, to the second, to apnea events for me.  I was really surprised how low O2 sats get when you have multiple events in quick succesion.  Very good data for those of us who are data focused.

Compared to the CMS 50D+, the rechargeable batteries alone make this one worth the extra $20 (IMHO).  The time stamp is also a very good feature the 50D+ doesn't have.

Compared to the CMS 50H, the only thing the 50E doesn't have is perfusion index.  Not worth the extra $20 (IMHO).

Compared to the CMS 50F, you'll have to decide if the watch type base unit and external sensor is worth the extra $50.  Note:  The CMS 50I wrist base/sensor should be on the market soon.  Looks smaller!

Pros:
1. Small, relatively light weight.  It's only fallen off my finger a couple times during the night.  Everyone has different fingers, so your experience will likely vary.

2. Screen is easy to read.  When is record mode, it turn off in about ten seconds so it doesn't disturb you during the night.

3. The software is good and the .Spo2 files can be downloaded directly into Sleepyhead.  Note:  If you go to the directory where the .Spo2 files are stored you should also have .csv (comma separated variable) files that can be imported to MS Excel or your favorite statistical program.  These have the raw data at a one point per second recording rate.

4. Rechargeable battery.  The battery charges via the USB cable and supplied AC adapter.  I've never tried pushing it past two nights.  Just plug it in in the morning and it's ready to go.

5. Time can be set but must be set each night when you start the RECORD function.  The setting does not stay, you have to redo it every night.

Cons:
1. The USB cord that came with it is not a standard Micro USB cord.  I've tried the oximeter with three other standard Micro USB cords I have and I've tried the suppled cord with other USB devices I have and it doesn't work.  Maybe that's why the USB connector end is so large.  There is some kind of USB/Serial electronics in it?  Don't know.

2.  The alarm is LOUD!  If I set it so I know if it comes off my finger it wakes me up, wakes my wife up, wakes the cats up.  No volume adjust that I know of.

3. The documentation is a bad translation.  I think most people can figure it out with little trouble.  Once you understand the unit, you'll never need the instructions again.


"SpO2" and "SpO2 Review" software
- Paula has already posted an excellent review of the software in the CMS-50D+ review thread.
- Please see the Wiki article "Importing CMS 50D Plus oximeter data into Sleephead."  I think we can thank Paula for this as well.

[b360155]

Pulse Oximeter CMS-50E
Compared to the CMS 50D+, the rechargeable batteries alone make this one worth the extra $20 (IMHO). The time stamp is also a very good feature the 50D+ doesn't have.

- Please see the Wiki article "Importing CMS 50D Plus oximeter data into Sleephead." I think we can thank Paula for this as well.

Yeah, saw this model after I purchased my CMS-50D+. I think the 2 are pretty much the same except for the rechargeable battery feature, the time stamp feature and a carrying case. But carrying case is no big deal to me and time stamp feature doesn't sound like anything special if you have to re-set it every night. So, the main thing like you say seems to be the rechargeable battery. Is the battery removable at all or is built in? I've been using some Radio Shack rechargeables that I already had for my CMS-50D+ and recharge after every 2 nights use.

And I think Paula will give credit where credit is due and will tell you as she's done before that pssnn was the author of the well-written Wiki article.

[PaulaO2]

Yes, pssnn wrote the Sleepyhead article. Much better job than I could ever do!

Great review.

As my issues with the meter I have increase, I may be investing more money into another one. Not sure if it will be this one, though.

[jdireton]

I checked the unit and I don't see any way to disassemble it to access the rechargeable battery. So when the rechargeable cell dies, the unit will be worthless. Likely another con compared to the 50D+.

The case and neck lanyard were put in the trash right after I opened the box, again, not a reason to buy this model.

That said, it does charge from my computer USB port, so it is way convenient vs. having to remove rechargeable cells, put them in a charger, and put them back in when complete. When I read it out, I just leave it connected and it is ready to go that night.

[PaulaO2]

I have the 50D plus. I hang the lanyard on a nail and during the day, clip the device to it. I lose small things like that all the time.

[TorontoCPAPguy]

Imagine that. This was the first thread I read upon joining and it is way out in left field.
Firstly, the CMS50E is not intended for all-night recording without some means of holding it onto your finger unless you are catatonic..... I highly recommend a small piece of blue painters' masking tape and it has worked for me for years, as has my CMS50E. I have TWO of them and they are different, believe it or not!
The first one uses a software version below 1.00 and the second one that is above 1.00. The first one uses a proprietary USB cable and the second one any standard USB cable with a micro end on it. They now have a new one out that also has Bluetooth if you have a laptop with Bluetooth! There are utilites around to match the output to your CPAP software as well.

As to the battery in the unit.... my units are two plus years old and still running strong. I would not expect to get much more than two or three years on the battery but this one looks like it is lithium and is going to last a lot longer. Nontheless, should you need to replace it, the case simple "cracks" apart like much electronics on the market using a very thing wedge or your fingernails..... or you can do what I did and drop it on the floor and have it pop apart.

As to accuracy; regretably I have had a number of opportunities to compare it to hospital based units and it is just about dead accurate. I suffer from a plethora of maladies after a bout of acute pneumonia (as acute as you can get) in summer 2009 that had me on full intubated-type life support in lala land for three weeks where they wanted to pull the plug. My lungs are now under 70% capacity so SpO2 was an essential number for me to have in my combat with sleep apnea. We discovered that even with the CPAP/APAP machine, my SpO2 would plummet at times into the 70's.... the usual story and runaround with the eggheaded MD's checking for allergies and stuff and I just went out and bought an oxygen concentrator and started infusing 3-4L/M of oxygen into the airline, increasing the O2 % from 21% to about 35% and presto! my O2 problem was gone. Afterwards, I got an Rx for O2 from the respirologist.

I still had issues with SpO2 when I was not on O2. Too severe for just lung damage due to the pneumonia, etc. And then I was diagnosed with Atrial Fibrillation. Battle stations! again. My left atrium was enlarged and so I was not a candidate for catheter PVI ablation surgery (day surgery sorta).... in December they started my on a new drug called TIKOSYN and I have been pretty much in NSR ever since.

Now the point of all this..... OSA is related and a causitive for Atrial Fibrillation, diabetes and a host of other things. You want to keep your gear washed down and disinfected where possible. I have FOUR full face masks and FOUR hoses and I rotate through them so I only have to wash and disinfect about once a month or so. I wipe everything down daily with a green wipe. ALL ODOURLESS as it is a proven fact that any strange odours at sleepy time will cause your brain to work overtime (fight or flight) and help ruin your sleep.

The object of the game, of course, is not just to get your AHI to 0.0 every night (mine is) but to get your REM sleep maximized. If your SpO2 is dropping regardless of AHI - I guarantee you are not getting your full share of REM or L4 sleep as the CO content of your blood is high and is waking you up although you may not know it. Hence the critical importance of a good all-night recording, rechargeable pulse oximeter with a graph and software. That pulse oximeter will also show if your ticker is pumping out a regular supply of blood. If the pulse part of the graph is erratic, see your doctor immediately as it is indicative of Atrial Fibrillation or worse (and that is dangerous). Your body is not getting a full load of oxygenated blood pumped around and even if you are showing as having OSA and have 'cured' it.... you are still not going to get a good night of sleep due to higher concentrations of CO in your blood, inverseley proportional to your SpO2.

Your investment in that pulse oximeter is not just a luxury or a toy as your family or friends may jab at you, but it is CRITICAL empirical data which is essential to your health.

I am not a doctor and cannot recommend that you take my advice or follow my course of action, but I have titrated my own pressures almost since day 1 to great effect and would recommend nothing but an APAP machine and a FULL face mask. Forget about taping, headgear, having your teeth screwed together or whatever. Get a FFM like the Respironics Quattro Pro and get it as large as you can without bothering your eyeballs so that it does not touch your nose and is spread out over your face for greatest stability. If you are bothered by being suffocated should the APAP shut down try shutting it down yourself and see what happens. See that swivel at the entrance to the mask? If you are really panicky you should know that it breaks away with not too much pressure and you have a great supply of room air. In fact, if I have to go to the washroom at night, that is exactly what I do rather than removing the mask and having to readjust it on putting it back on.

AHI=0.0 is a good start and you will only get there if you can keep the pressure going down your windpipe and not out your mouth. I tried pillows, nose masks and hybrids. The problem is always having air escape from your mouth. FFM? No issues.

I am about to order a couple of the CMS 50E's with Bluetooth to cut down on cable clutter; you will know I like them when you see my older CMS0E's come up for sale. As far as I am concerned the CMS50E is gold.

I have TWO s9 Autoset II's I like them so much (replaced S8 Autoset II's) and I have one S8 Escape which is intended for camping or travel and nothing more (I would not even use an Escape for that to be honest.... an APAP machine works much better.... like the S9 or any other Autoset). Whatever you use.... that pulse oximeter is probably more important data than anything else and the CMS50E is just fine for the task at hand.

Hope this helps clear the fog a bit. Not an expert but have taken much time to educate myself on sleep apnea and on aFib as they will ruin your life for sure and did so for me.

I am also supplementing with vitamins and essential nutrients but that's a story for another day. Get your GP to check your Magnesium, Potassium, etc. I also supplement Taurine, CoEnzyme Q10 Ubiquinol and a host of other things like B series vitamins and time release Vitamin C. Stopped for two weeks to see if it made a difference. It does. Big time. D-Ribose keeps my heart calm and helps me sleep I think. Am feeling great excepting the aches and pains of aging at 60 (please don't tell me it is going to get worse!)

Wishing everyone a great night of sleep and a great day of sunshine tomorrow!

TorontoCPAPguy
Richmond Hill, Ontario
and all over the USA when it gets cold up here.

[TorontoCPAPguy]

Just ordered a Contec CMS50EW from one of the supplier links on this forum! It will replace one of my CMS50E units that use a USB cable to cut down on cable clutter. They also had fingertip rubber cups if you want to wear it all night without using a piece of masking tape. The unit was $120 shipped from most suppliers (I checked my regular supplier as well) and the fingertip cup was $70 shipped (tape is cheaper).

I will start a thread here to report once I have tried it a few nights and have a chance to compare its accuracy to a standard, etc.

[b360155]

Thanks for the excellent write-ups TorontoCPAPguy! Which number supplier on the list are you using? I didn't see the fingertip cup but was just curious what this thing looked like for $70??? Welcome to Apnea Board!

[TorontoCPAPguy]

Thanks for the excellent write-ups TorontoCPAPguy! Which number supplier on the list are you using? I didn't see the fingertip cup but was just curious what this thing looked like for $70??? Welcome to Apnea Board!

Don't see them on the list ... perhaps an advertiser? The outfit is called Amperor Direct and I have never dealt with them before; but they take PayPal and PayPal has been a great mediator for me in past years with online deals that have gone astray.

Anyway, I will surely report back and let everyone know how the new CMS50EW works with Bluetooth. Now I need to find the software again that interfaces the CMS50E's data into ResScan software so it shows up as the SpO2 data.

One thing I have noted about the CMS50 line is that it is very sensitive to movement; both the readings and the graphical representation of one's pulse go all wonky if you move about. Not enough to make a huge difference in SpO2 and pulse rate, but it is not the unit I would choose if I was a jogger, for instance.
Otherwise, not only was I impressed.... the nurses at the hospital where I have spent far too much time as of late were also quite impressed... especially when they did rounds during the night squeeking and clanging along with their pole mounted unit from room to room.

BTW, I shared a room with the kid that was shot during a bungled robbery attempt in Newmarket, Ontario in December while I was having TIKOSYN administered and titrated for my aFib. The kid took a bullet in the gut and had a colostomy as a result. Not a fun roomate to have, especially at mealtime.

[Surly]

Now I need to find the software again that interfaces the CMS50E's data into ResScan software so it shows up as the SpO2 data.

Is this software publicly available?