REVIEW: Contec CMS-60D Handheld Oximeter

DreamDiver wrote:I just bought the Contec CMS-60D from Southeastern Medical Supply, Inc.


I ordered it on Tuesday and received it on Thursday with free shipping! While the order said it would come via US mail, it came via UPS. An auto email alert sent by SE Medical and a corresponding UPS email told me it was shipping and when it would arrive. Ironically this is probably faster, cheaper and more reliable than US mail would have been. Works for me.

It came with free shipping for $249.95. Included with the purchase were these items:

• 1 oximeter unit
• 1 Adult finger sensor
• 1 USB Cord with standard USB to mini-USB plugs
• 1 Mini-CD with a windows software installer
• 2 AA Batteries
• 1 User Manual

Oximeter Unit:
The unit itself measures 4 3/8 inches tall by 2 3/8 inches wide by 1 inch at its thickest. It actually has a dark gray front and back rather than a white front and gray back as shown in the ad.

The blue keypad has six keys on it: a power button, a menu button, and four arrow buttons. The left arrow button also has an alarm mute icon on it. I like that the unit takes 2 AA batteries. You can use rechargeable batteries of your own too. There is an LED on the top left of the box when it is facing you in 'right-reading' position that I have yet to see actually light up. There is a translucent silicone flap on the bottom left side of the box where the mini-usb plug fits. The battery cover is a little looser than I would prefer, but okay. Overall the box feels substantial without being too heavy. It's bigger than an ipod, but will still fit in a shirt or pants pocket for daytime use. It is unobtrusive under your spouse's pillow for use during sleep.


Visual Display:

The visual display has a resolution of 160 pixels by 96 pixels and is 1 1/2 inches across by 1 1/8 inch tall with a temporary scratch plastic protector on it. That works out to about 1.87 inches on the diagonal. The display on the advertisement is obviously a mockup image and not an actual photo because, pixel-per-inch the display is 10% larger in the advertisement than the display on the machine I got. That aside, the it is a clean OLED display with three brightness settings. The brightest setting is visible in full daylight. The medium brightness is good for indoors and may help preserve battery life. The lowest setting is just bright enough not to be obnoxious when you're half asleep in a pitch-dark room. The display is surrounded on all sides by a silvered area with the word "CONTEC" bordering the lower edge of the display.


Finger Sensor:
The adult finger sensor looks pretty much as displayed. The one I got has a yellow compression fitting around the end that plugs into the box. The gray cord leading to the finger sensor is just over 5 feet 1 1/2 inches long. The sensor is a light beige/gray with black neoprene cradle material inside on either side of the clip. The clip of the finger sensor has an expansion spring for larger fingers. It will easily stay on all night without applying too much pressure. I had it on one finger for about 6 1/2 hours last night. While it didn't leave a mark, the spot where the sensor touched by skin felt burned by the infrared LED that accompanies the red LED inside the sensor. If there is any perspiration at all on your fingers, you may notice an electric prickling sensation on the wire side of the sensor. My fingers weren't sweaty, but they were just a little clammy. This sensor cannot be worn on wet fingers - this will void the warranty. I can remember a similar sensation at the sleep lab, but cannot remember clearly if the burning felt that intense. As I write this, that spot on my finger is still sensitive. I wonder if this is a problem with all finger sensors or just with this particular product.


USB Cord:
The USB cord is black and 5 feet long with a standard mini-usb male plug that goes into the unit.

User Manual:
This is likely the same identical manual talked about by Arizona-Willie in his review of the CMS-50E
The manual could definitely do with a rewrite. No mention is made of the software.

Navigating the Visual Display:
There are four main display panels. The first display is the default, showing in large numbers your specific 02 and pulse, as well as the plethysmograph 'heart beat' graph that adds a sort of professional touch. All the most important data is visible.

The second display panel is accessed by hitting the 'up' arrow and is titled 'Mode 1'. This is a display showing whatever has been recorded and is still in memory. It shows a navigable graph almost 2 minutes wide with SPO2 in yellow and heart rate in red on a black field. Right and left arrows allow you to navigate between sections.

If you hit the menu key next, you'll go into the third panel entitled 'Mode 2'. In this mode, a tiny blue arrow at the top of the graph can be used to navigate each second of the graph for exact spO2 and pulse rate readings at a specific time using the right and left arrows. Hit the menu key again to get back to Mode 1, or the up arrow to go back to default display.

The fourth panel - the menu - is very simple. You can control the Alarms through a submenu, whether you hear a beep for every single pulse, brightness, recording and upload. The only submenu is for the alarms: SP02 Hi and Low Alarms, Pulse Rate Hi and Low Alarms, plus a master Alarm On/Off setting.


Recording data:

1. Press the 'Menu' button.
2. Navigate to 'Record'.
3. Touch the right or left arrow until it says 'Yes'.
4. You'll see a dialog: "You will recover the Memory! Are you Sure?"
   It should say "This will delete all stored data! Are you sure?"
5. Left or right arrow to 'Yes'.
6. Navigate down to 'Hour' and 'Minute'
7. Input the correct time in military hours and minutes.
8. You'll use the right and left arrows to change the numbers to the correct time.
9. When you press Menu again, it takes about 5 seconds for the recording to begin.
   The recording will turn off the display to save energy after about 35 seconds with a quick
   splash screen that says 'Recording...' Pressing any of the arrow keys or the menu brings
   the 'Recording...' splash screen back for 2 seconds as a reminder.
10. You can bring back the default screen and access to the other screens by touching the 'Power' button again.
11. To stop recording, navigate again to 'Record' and turn it off.

Navigating the Software:
The installer CD installs two programs: "SPO2" and "SPO2 Review". After they're installed each program will ask you the first time what language you want to use. You have a choice of German, English or Chinese.
To watch your data live on your computer, use SPO2.

1. Turn on and start using the oximeter.
2. Turn on SPO2 on your computer.
3. Connect the USB cord from your unit to the computer.
4. It may take a moment for the data to show on your monitor, but it should show in quadrant 1.
5. You can print out a trend graph that will be black with yellow and red lines - pretty impractical.

To review data recorded previously on your unit, use SP02 Review without being hooked up to the unit.

1. First turn on SPO2 Review on your computer
2. Second, click the 'magnifying glass' icon. If the unit is not connected, it will give you an alert and ask for a file to load.
3. By default, you'll be in the folder where data is saved. Just open the file you're interested in and the data will display.

To upload data from the unit:

1. Turn on the oximeter.
2. Turn on SPO2 Review on your computer.
3. Connect the usb cable from the unit to the computer.
4. On the computer, press the "magnifying glass" icon.
5. Fill out the personal information on the computer and click okay.
6. The computer will tell you it's waiting.
7. On the unit, navigate to 'Upload' and 'Yes'.
8. It will take a while to upload the data, depending on the amount of data there is to upload.
9. From here you can either, print, change analysis parameters or close the session.

To print reports, click the 'Printer' icon and decide on the type of report you want. Print it out.

EDIT 08/31/2008

Drivers:
There there are three proprietary drivers installed by the software:
C:\WINDOWS\system32\DRIVERS\silabenm.sys,
C:\WINDOWS\system32\DRIVERS\silabser.sys,
C:\WINDOWS\system32\WdfConinstaller01005.dll
for something called Silicon Labs CP210x USB to UART Bridge (COM7)

The way it's set up, I doubt it would interfere with other USB installs on WinXP.

Accuracy Comparison to the SPO 7500:
Accuracy specs compared with another popular machine:

Code: Select all

									CMS-60D			SPO 7500
SPO2:
Measurement Range:			35% - 99%	   40% - 99%
Resolution:					 1%				 1%
Accuracy: 					  +- 2%*			+/- 2%

Heart (Pulse) Rate:
Measurement Range: 		  30 - 250 BPM	40 - 250 bpm
Resolution:					 1 BPM			 1BPM
Accuracy:						+- 2%			 +/- 3%

*in range 70% - 100%

So the accuracy is about the same as one of the more popular oximeters on this board. I was not able to find out what type of accuracy the SPO 7500 has at lower SpO2 levels.

Battery Duration:
I have not changed the batteries yet, but have so far used it for well over 24 hours. I'll report back on how long they last.
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Pros:

• Uses standard and rechargeable AA batteries.
• Finger Sensor is detachable. You can buy a new one if it breaks or if you need a child sized sensor or ear lobe sensor.
• This is an inexpensive alternative to much higher-cost oximeters that does a lot for the amount of money you pay.
• Data is saved in non-destructive flash memory, so if you pull the batteries out while the machine is off, you won't lose data.
• The data is relatively easy to upload and read.
• There is no glossy printed boxing or packaging. To me this is a plus - the product speaks for
  itself, and the absence of expensive retail glossy packaging is less wasteful.

Cons: EDITED 8/30/2008
Keep in mind that most of these are about small things, not necessarily about the machine itself.

• Software could definitely use improvement.
• No internal clock. You have to set the time each time you start recording.
• No carrying case.
• No belt clip.
• No long-term video display protective sheets.
• No rechargeable NiMH AA Batteries, charging cradle with included usb/wall adapter.
• The unit does not turn off if no finger is sensed in the finger sensor after 5 or 10 minutes. If the alarms are off, and the unit is just displaying and not recording, this might have been nice.
• No software user manual!!! Granted, the software is easy to install and doesn't take long to figure out on your own, but unless you have a knack for how peripherals might work with computers, a user could get seriously frustrated.
• Ineffective user manual - it makes reference to a non-existent packing list and is written in poorly translated English.
• It might have been nice if there were also fewer plastic bags and maybe paper wrapping instead.
• Either the unit or the sensor emits some sort of radio or television wavelength static on some frequencies, one second long every other second. I found this out by listening on my mp3 player and hearing transmission chatter when the machine is on. It's not loud, but it is annoying.

Overall:
What more can you ask for? It has a live readout for Specific O2 and Pulse rate. Since the technology uses plethysmography as a way to measure these, it makes me wonder whether they couldn't have given a reasonable estimate of blood pressure as well. Sooner or later, someone will figure it out. The most important capability is being able to print out reports from data captured and viewed with the review software. The OLED screen is clear, in color and sharp. I prefer this system to the all-on-the-finger type because of the componentry. If the sensor breaks, you don't have to buy a whole new unit. I can use easily-obtained AA batteries. This unit likely uses the same basic hardware and firmware as the CMS-50E and several other Contec oximeters.

I've got a lot to learn about reading these before I can make too much sense of them. What I wonder about is the burning sensation from the finger sensor and whether this is something that shouldn't be happening.

Example Reports in pdf format:
Full Report
Oximetry Report
Strip Chart Report
Summary Report

Software Manuals I found on another site:
Installation Manual
SPO2 Review Manual

Four Screen Views of the Software


Four-Station View - SPO2


Single Station View - SPO2


SPO2 Review - Example Data


SPO2 Review - Upload Example

I hope this helps somebody.

SleepyNoMore wrote:

DreamDiver wrote: Cons:...

• ...
• No rechargeable NiMH AA Batteries, charging cradle with included usb/wall adapter.
• ...

... don't they have one that comes with an electrical plug in???...

SleepyNoMore wrote:Absoutley, yes it would be easier I agree but I just hate having to buy batteries period... It really should come with a rechargable cradle and an electrical plug in (both)

billbolton wrote:The CMS 60D does come with an internal rechargable battery which can be charged by plugging it into any USB port!

Cheers,

Bill

DreamDiver wrote:I've been looking around for information about the finger sensor. It would be nice to have an idea of of what's actually in there. I get the impression there are at least these three types of emission and three detector arrays:

1. red laser - probably like an an optical mouse - to sense whether a finger is present and also as a visual cue for the wearer that the unit is functioning and relaying information to and from the finger sensor.
2. infra-red laser - probably responsible for measuring SPO2.
3. electrical resistance - probably for the pulse plethysmography. You can feel it tingling on the side of the sensor that doesn't flash red light.

Is that correct?

feeling_better wrote: Where you just guessing about the third item? I do not think there is any resistance sensor, at least not for getting that waveform. Here is the proof: Just lift the finger from the receiver (the non led side) surface a mm or so. The wave is still there and it measuring accurately! Also you can put the clip upside down, with the wire on the palm side. Even with the sensor on the nail, it works almost as well.

DreamDiver wrote:... I didn't get burned the second night. I'm wondering if there is an initial "burn-in" period where the sensor is more powerful than it should be. However, I didn't leave it on any finger more than a few hours this time, so I'm still not sure. It makes me wonder about the useful life of the sensor...

feeling_better wrote:

DreamDiver wrote:... I didn't get burned the second night. I'm wondering if there is an initial "burn-in" period where the sensor is more powerful than it should be. However, I didn't leave it on any finger more than a few hours this time, so I'm still not sure. It makes me wonder about the useful life of the sensor...

DreamDiver, I did not experience any of that burning sensation; of course it is possible that my skin might be less sensitive. By any chance did you have the led on the skin side and the receiver on the nail side? The reason I ask this is that, the instrument appears to function just as well this way, and normally with the led on the nail side, the nail may be diffusing the beam quite a bit.

DreamDiver wrote:I've been looking around for information about the finger sensor. It would be nice to have an idea of of what's actually in there. I get the impression there are at least these three types of emission and three detector arrays:

1. red laser - probably like an an optical mouse - to sense whether a finger is present and also as a visual cue for the wearer that the unit is functioning and relaying information to and from the finger sensor.
2. infra-red laser - probably responsible for measuring SPO2.
   ...