Review of PC based recording Pulse-Oximeter
I've had my CMS-P for about a week now. If you are looking for a low cost recording oximeter, this might appeal to you.
I got it on a "buy-it-now" eBay auction for $99 including free EMS shipping from vendor "medonline888". EMS shipping is quite fast - I had it in four working days. Of course, the CMS-P is available elsewhere for $99 + shipping, but I've never had any problems with buying from China via eBay so I went for it.
The storage container is kind of interesting. It's in a metal can with a window on top. The software CD is actually in the can also - it's one of the mini CD's.
Finger sensor:
The finger sensor unit has no fancy display or readout like the higher priced CMS models. This seems appropriate to me since I really can't watch a readout while I'm sleeping anyway. It's powered by the USB port from your PC, so no batteries are needed.
There were no instructions on how to use the sensor itself, so I just stuck it on my finger
I did find it helpful to secure the probe and the cord to your finger with some type of medical bandage tape to reduce the chances of it being pulled off in your sleep.
The finger sensor feels well made. The USB cable is about 10 feet long and has strain reliefs built into both the sensor and USB plug ends. It feels comfortable when you place it on your finger. The pivot point is floating, so it will adjust to thicker fingers to allow a relatively uniform pressure across the entire padded area that contacts your finger. I have experienced some soreness in the area right behind my fingernail after wearing the sensor for an entire night. I can't quite figure out why this is happening. If anyone has an explanation or suggestion, I'd welcome your input.
UPDATE: I may have been placing my finger to far into the sensor - the LED's should apparently be centered over the nail bed.
The Software:
The software that gets installed on your PC consists of two programs: SpO2 Manager and SpO2 Review.
SpO2 Manager is the real time display and recording program. The program is able to display real time data for 4 patients simultaneously - presumably by connecting 4 sensors to the PC at once. Patient windows can be drug around and rearranged if needed. Double clicking on the active window (or any window) will blow it up to fill the entire window alone. This is probably the first thing you will do if you only have one sensor connected. Window displays can also be selected via icons at the bottom of the screen. The SpO2 manager screen shows a running trend graph of both pulse rate and SpO2 saturation levels. That graph takes up a little over half the screen. The window period of this trend graph can be set to 1min, 10min, 30min, or 60 minutes.
Below the running trend graph is a real time display of your pulse in a classic medical oscilloscope format (very cool).
Along the right side of the screen is a numeric readout of your pulse rate in BPM and your SpO2 percentage. In the bottom right corner is some eye candy consisting of a little heart beating and a pulsing bar graph.
The bottom of the screen has several other control buttons (in addition to the patient window selection icons already mentioned). The "i" control button is for entering patient information in the currently selected window (if active). There is a language selection pull-down, and also a printer button - for report generation, that will be described below.
Alarm levels can be set by right clicking in the units area on the left or right hand side of the running trend graph area. These are visual alarms only - no sound options that I could find.
Recording data:
Recording of data begins as soon as SpO2 manager starts. For this reason, I prefer to have the sensor attached and secured to my finger before I start the program. The preferred method for storing data when your session is over is to unplug the USB cable. When unplugging the sensor, the program will prompt you to enter the patient information once more if you forgot to enter it earlier. It will then auto-generate a file name (changeable) and will save three data files. The binary data file has an .spo extension. This is the file that can be loaded into SpO2 Review which will be described next. Also saved are two .csv files that can be loaded into MS excel for plotting. One of the .csv files contains the data for the trend graph, the other file (which tends to be huge) is the pulse trace data. An 8.5 hour session generated an .spo file that was only 150kb in size. Here is a screenshot of SpO2 manager running on my computer.
Reviewing data and generating reports:
SpO2 Review is the program that is used to quickly view the data and to generate reports. The data from previous sessions is stored in the .spo files as described above. SpO2 review can also directly download data from some of the higher priced recording oximeters (such as the CMS-50E and CMS-60), but in this case, it is just used to open data files created by SpO2 manager. After the file is loaded, the trend graph is displayed. At this point you can select the time window and can also scroll or page through the data.
The most useful part of SpO2 Review is the report generation options that appear when you click on the printer icon. The reports can also be previewed before printing. Here examples of the four types of reports. (These are .pdf files)
OxiMetry Report
Summary Report
Full Study Report
Strip Chart Report
I find the OxiMetry report the most useful (it's the first link listed above).
The Summary report is similar to the OxiMetry report, except with a few things deleted to make room for doctor comments, etc.
The Full Study report shows the entire trend graph in a stretched-out format (may be multiple pages in length)
The Strip Chart report allows you to print a zoomed in area of the chart.
That about covers my experiences with the CMS-P so far. I did encounter a problem trying to run the programs on my old W2K laptop with only 128mb of ram. Both programs would crash with a stack overflow error when run. I'm not sure if it was a W2K problem, a lack memory problem, or what. I have loaded the software onto two other WinXP desktops, in addition to my Vista laptop and all ran the software fine. All of those machines had 2gb of memory.
For a review of the CMS-50E, you might want to refer to this thread:
viewtopic/t28525/Report-on-CMS50E-Pulse-Oximeter.html
The same software is used on both the CMS-50E and the CMS-P. (and various other CMS oximeters that have recording capability)