Oximeter Reviews

[kasiahbug]

I'm looking at purchasing a new Oximeter for my son. 
We use a Vibe O2 during the day to show drops and things but looking at the oximeter cms50f and oximeter cms50i, etc for night use. I want to be able to import into sleepyhead - 
I've looked over the board but most info is old, so I want to make sure I make the best decision now - 
Any feedback on the best monitor to use? (Or any I have not mentioned?)

(He has a C-pap but waiting on BiPAP now). 

[Crimson Nape]

The preferred oximeter is the CMS-50 series, models D+, F, and I.  The D+ is an all-in-one unit that is harder to keep attached during sleep.  The "F" and "I" models are a wrist worn device with a detachable finger probe.  

The differences between the "F" and "I" are:

1. The "F" is FDA approved in the U.S. (as if that really matters), the "I" has to be ordered from off shore suppliers.
   
2. The "F" model only records one session, the "I" allows up to 15 sessions to be stored. The actual number is dependent on the size of each session.
   
3. The "F" reports the SpO₂ and pulse, the "I" records the same plus the Perfusion Index.
   

The pricing is progressive through the models.  With that said, the "I" model can be the same price as the "F" due to the different purchasing location.

One last thought; There are comparable models that have the bluetooth option (a "W" is added to the model letter).  This feature doesn't offer any benefit for its intended use.  This is more for a Doctor's office to capture data in real time.

I hope this provides you some insight.

- Red

[ardenum]

Oximeter Oxy310U is what I have its got multiply save slots and you can set it up to save only drops in %O2 and it saves when it happened, its got its own software to readout the data.

[kasiahbug]

The preferred oximeter is the CMS-50 series, models D+, F, and I.  The D+ is an all-in-one unit that is harder to keep attached during sleep.  The "F" and "I" models are a wrist worn device with a detachable finger probe.  

The differences between the "F" and "I" are:

1. The "F" is FDA approved in the U.S. (as if that really matters), the "I" has to be ordered from off shore suppliers.
   
2. The "F" model only records one session, the "I" allows up to 15 sessions to be stored. The actual number is dependent on the size of each session.
   
3. The "F" reports the SpO₂ and pulse, the "I" records the same plus the Perfusion Index.
   

The pricing is progressive through the models.  With that said, the "I" model can be the same price as the "F" due to the different purchasing location.

One last thought; There are comparable models that have the bluetooth option (a "W" is added to the model letter).  This feature doesn't offer any benefit for its intended use.  This is more for a Doctor's office to capture data in real time.

I hope this provides you some insight.

- Red

Thank you, this is VERY helpful. 

Actually I was looking at bluetooth since my son will be wearing it and I can monitor elsewhere in the house if needed???

[Crimson Nape]

Bluetooth's specification limits the connection to around 30 feet (9.1 meters) between the device and the receiver.

The software that accompanies the CMS-50, SpO2 Assistant, is used for real-time monitoring, analysis and data download. SleepyHead can perform a direct import from the device as well. Please be aware that a bug has crept into the latest version of SleepyHead that messes with the import time and duration. The current work-around is to import the ".spo2" file downloaded using SpO2 Assistant. The SH version coming down the pipeline will have this bug addressed, but is a few months (fingers crossed) away.

[ShaunBlake]

The preferred oximeter is the CMS-50 series, models D+, F, and I.  The D+ is an all-in-one unit that is harder to keep attached during sleep.  The "F" and "I" models are a wrist worn device with a detachable finger probe.  

...
I hope this provides you some insight.

- Red

Thank you, this is VERY helpful. 
Actually I was looking at bluetooth since my son will be wearing it and I can monitor elsewhere in the house if needed??? 

kasiahbug, that is understandable; however I expect that over time you will not find instant observation of O² sat to be important. Additionally, Bluetooth is expensive in electricity (heavy drain on batteries) as well as implemented circuitry.  Most folks — even those who experience very low saturation — find that checking the recordings after a sleep period is sufficient.

My suggestion is to focus on other criteria for your selection; if the ideal device happens to include Bluetooth, okay.

I have a CMS 550F, which serves nicely and I've found its recordings are the same as more expensive and horribly expensive devices.  Pretty good for about eighty bucks!

However, the promised 72 hours of stored data has been elusive.  At one time I was able to record three overnight sessions and download them to my computer.  Another time I was able to download two sessions.  Now I find that, regardless of how long/short the sleep period, only the most recent is available for download.  (I attribute this shifting sand to the Contec Medical devices being cheap Chinese junk.)

Hope that helps. Please keep us posted!

[PaulaO2]

In terms of the reviews, not much if anything has changed with the oximeters reviewed. They don't change all that much and if they do, they get another letter after the name.

[Fats Drywaller]

However, the promised 72 hours of stored data has been elusive.  At one time I was able to record three overnight sessions and download them to my computer.  Another time I was able to download two sessions.  Now I find that, regardless of how long/short the sleep period, only the most recent is available for download.  (I attribute this shifting sand to the Contec Medical devices being cheap Chinese junk.)

An interesting observation, thanks.  (I'll probably be shopping for one of those devices eventually.)  Your assumption about cheap Chinese junk is probably true, and more specifically, most likely the firmware wasn't written carefully to conserve the flash RAM by doing wear leveling.

Wikipedia: Wear leveling: types

The problem is that a write cycle doesn't happen only once per sleep session; it happens whenever the program needs to write to the nonvolatile memory, and that's entirely up to whether the programmer took care to minimize those writes.

As for why one session's worth of data remains available for much longer, a guess is based on this from the wikipedia page: "EEPROM and flash memory media have individually erasable segments, each of which can be put through a limited number of erase cycles before becoming unreliable. This is usually around 3,000/5,000 cycles but many flash devices have one block with a specially extended life of 100,000+ cycles that can be used by the Flash memory controller to track wear and movement of data across segments." So maybe the programmers knew that would be a problem, and used a two-tier flash-RAM configuration with one session's worth of data kept in a more durable chip? I dunno.

[kasiahbug]

Bluetooth's specification limits the connection to around 30 feet (9.1 meters) between the device and the receiver.

The software that accompanies the CMS-50, SpO2 Assistant, is used for real-time monitoring, analysis and data download.  SleepyHead can perform a direct import from the device as well.  Please be aware that a bug has crept into the latest version of SleepyHead that messes with the import time and duration.  The current work-around is to import the ".spo2" file downloaded using SpO2 Assistant.  The SH version coming down the pipeline will have this bug addressed, but is a few months (fingers crossed) away.

Thank you  - 
I am right above his room, so could read it from there I'm sure - and if it works ok, the school nurse would like to keep tabs at school. 
We are using the O2 Vibe but noticed the pulse is way off, saying his HR was 50 and it was actually 120, so not just a little and therefore not sure if O2 is accurate or not. I plan to take two wrist devices during the day one weekend and really do a trial run. He's on oxygen during most of the day so it's imperative we have accuracy.

---

The preferred oximeter is the CMS-50 series, models D+, F, and I.  The D+ is an all-in-one unit that is harder to keep attached during sleep.  The "F" and "I" models are a wrist worn device with a detachable finger probe.  

...
I hope this provides you some insight.

- Red

Thank you, this is VERY helpful. 
Actually I was looking at bluetooth since my son will be wearing it and I can monitor elsewhere in the house if needed??? 

kasiahbug, that is understandable; however I expect that over time you will not find instant observation of O² sat to be important. Additionally, Bluetooth is expensive in electricity (heavy drain on batteries) as well as implemented circuitry.  Most folks — even those who experience very low saturation — find that checking the recordings after a sleep period is sufficient.

My suggestion is to focus on other criteria for your selection; if the ideal device happens to include Bluetooth, okay.

I have a CMS 550F, which serves nicely and I've found its recordings are the same as more expensive and horribly expensive devices.  Pretty good for about eighty bucks!

However, the promised 72 hours of stored data has been elusive.  At one time I was able to record three overnight sessions and download them to my computer.  Another time I was able to download two sessions.  Now I find that, regardless of how long/short the sleep period, only the most recent is available for download.  (I attribute this shifting sand to the Contec Medical devices being cheap Chinese junk.)

Hope that helps. Please keep us posted!

I found a CMS 550i for $65 on Aliexpress, I think I will start with that one and also look into the CMS 550F since I was expecting to pay close to $200 or more. 

[Crimson Nape]

I'm trying to provide you with information on things that can happen ahead of your CMS-50 implementation so you won't be surprised or concerned.  Rapid movement or bumping of the finger sensor will produce artifacts (outliers).  I believe that the sample rate is every six seconds.  The last statement is provided in case the topic comes up at a cocktail party.
- Red