Ambulatory Blood Pressure Monitor Support

Ambulatory blood pressure monitor ABPM50

Product Related Documents

Ambulatory blood pressure monitoring: Caution

Prolonged non-invasive blood pressure measurements in Auto mode may be associated with purport, ischemia and neuropathy in the limb wearing the cuff. When monitoring a patient, examine the extremities of the limb frequently for normal color, warmth and sensitivity. If any abnormality is observed, stop the blood pressure measurements.

  • You must not perform NIBP measurements on patients with sickle-cell disease or under any condition which the skin is damaged or expected to be damaged.
  • For a thrombasthenia patient, it is important to determine whether measurement of the blood pressure shall be done automatically. The determination should be based on clinical evaluation.
  • Do not apply the cuff to a limb that has an intravenous infusion or catheter in place. This could cause tissue damage around the catheter when infusion is slowed or blocked during cuff inflation.

Frequently Asked Questions

How to setup ABPM50 for continuous monitoring? ABPM50 must be properly initialized prior to doing ambulatory monitoring. Follow the steps outlined below.

  • Initialization
    • Set the measurement intervals, awake time and asleep time period. Awake time is the time when the subject gets up in the morning and asleep time is the time when the subject goes to bed at night. Awake interval is the measurement interval in minutes when the subject is awake; Asleep interval is the measurement interval while the subject is asleep.
    • From SYSTEM MENU >> SYSTEM TIME, set system time to current time.
  • Monitoring
    • From SYSTEM MENU, select ABPM.
    • Set "ABPM ON-OFF" to ON. Select YES to delete the ABPM data when starting a new measurement, otherwise select NO.
    • The ABPM will start to take measurement at the end of each interval.
    • To stop the measurement, press and hold the OK button.

Is there any ABPM data in my device? From SYSTEM MENU >> ABPM >> ABPM Data, you should be able to scroll through all the ABPM measurements. Note that these measurements are not the same as those taken manually.

How to download the data to the computer? After initializing the system and create a patient, follow the steps below to archive the measurements from ABPM.

  • Plug ABPM50 into an USB port on your computer using the provided USB cable.
  • Turn on the ABPM50.
  • Start the software.
  • Click the Download icon and follow instructions.

Where can I find the data on the computer? After saving the data to the computer, go to File >> Open Data and the dialog box (top diagram) would appear. By default, the data would be stored in [ABPM] folder. Select this folder, the dialog box (bottom diagram) shows all the data saved. Select the one you wanted and click "Okay". A window would appear displaying the data.

Open data

The above dialog box shows the patient name, patient ID, start time and file name. If the patient has not been setup, "nostring" would appear in the patient name field. The file name is based on the data timestamp.

By default, the files are stored in a sub-folder "Program Files\ABPM50\Data\ABPM50". If you are using WXP computer, the folder would be "c:\Program Files\ABPM50\Data\ABPM50"; For later versions of Windows (Vista, 7 and 8), the actual location would be "C:\Users\UserName\AppData\Local\VirtualStore\Program Files\ABPM50\Data\ABPM50." For the sake of security and ease of maintenance, Windows prevents software from writing into the "c:\Program Files" folder directly; Windows creates a Virtual Store for saving the data and different users using the computer can have their own virtual stores.

In Windows Explorer, one can go directly from "c:\Program Files\ABPM50\Data\ABPM50" to the corresponding virtual store by selecting the "Compatibility Files" button on the top.

How to assign patient info to a file? Select and open the file. Then go to Edit(tab) >> Patient Data and enter the patient related information. This would assign a patient ID and name to the selected file. The name and ID would show up in the "Open Data" screen next to the file name.

abpm50 patient data

How to reinstall software? You would need to remove the program first prior to installing a new one. Follow the following steps.

  • Uninstall the ABPM50 program from "Add & Remove Program," which can be found in control panel. As an alternative, go to Start >> All Programs >> ABPM50 Monitor >> Uninstall ABPM50 Monitor to remove the program.
  • Connect the device to the computer via the USB port.
  • Right click on Computer, select Manager >> Device Manager.
  • Look for CD Class example (under Other devices) or STM32 Virtual COM port Device (under Ports). If found, double click on the entry and select Driver tab and Uninstall.
  • Run ABPM50_Setup. A version of the program can be found in the download section above.

How to install the driver in Windows 8? Windows 8 would prevent the driver from being installed as it is not digitally signed. To get around this issue, disable the driver signature enforcement before installing the software. To disable this feature:

  • From Charms bar, select Settings >> "Change PC settings" >> "General" >> "Restart now" in "Advanced startup section" >> "Troubleshoot" >> "Advanced options" >> "Startup Settings" >> "Restart". The computer would restart.
  • During startup, select the "Disable driver signature enforcement" option.

Is the driver installed properly? If the installed software cannot find the ABPM50, the device driver may not be installed properly. To check for this possibility, plug in the ABPM50 in the computer USB port and make sure that it is turned on. Right click on "Computer" and select "Manage" > "Device Manager". If "STM32 Virtual COM port Device (COMx)" appears (see diagram below) , the device driver is installed properly; if "CD Class example" appears (see diagram below), Windows finds the device but not the driver; if no extra entry is found, Windows cannot find the device.

device manager - driver ok device manager - device ok

How to reinstall the device driver? Follow the following steps.

  • Download a new driver and save it to your hard disk.
  • Run the exe file and extract the folder "abpm50" to a temporary location. The folder contains two INF files, one is for 32-bit Windows and the other is for 64-bit Windows.
  • In device manager, double click "CD Class example".
  • Click the Driver tab, click Update Driver and follow the instructions.
  • When Windows asks for the driver location, set it to the folder "abpm50" in the temporary location.
  • Continue until the installation finishes.
  • Restart the PC.

Depending on your computer configuration, Windows may interfere with the installation because "file could not be verified because it does not have an associated catalog signed via Authenticode(tm)." If so, you would need to disable the Windows driver signature enforcement before installing the driver.

To disable the driver signature enforcement, when booting the computer and before starting Windows, press F8 key to enter the Advance Boot Options Menu and select disable driver signature enforcement.

How to check the USB connection? Try a different USB cable and/or USB port. Get another USB device to verify that the USB cable and USB port work.

Everthing checks out, but there is still no connection? Software conflict is the most common cause and the most difficult one to solve. The programs running on your PC are interfering with each other in accessing the COM port. One fix is to remove the offending program; however this works only if you know this is the problem and the trick is to find the offending programs. I am not aware of any easy way to determine the conflict. There are a few things you can do to look for hints.

  • Communication error messages (e.g. "Read COM failed") when running a program. This program is a partner involved in the conflict.
  • Error messages during system or program startup. The program generating the error message is another potential candidate.
  • Install the software on another PC (preferably a clean PC without installed programs that uses the USB port).

On a computer we used for testing various devices, we finally reinstalled Windows to solve the problem.

Possible fixes for resolving software conflicts are:

  • Uninstall the offending program.
  • Reinstall Windows
  • Multi-boot: By installing multiple operating systems on the same computer, you can built a "clean" one and run the software on this copy. The drawback is you would require extra disk space and at least two disk partitions, one for each copy.
  • Virtual machine: See Windows 8 Client Hyper-V, Microsoft Windows virtual PC, Oracle VM VirtualBox, VMware virtual machine and Windows XP virtual machine. Each virtual machine would run within its own environment and would eliminate any interference. When building a virtual machine, do not copy from one that contains the conflicting software.

The application does not use a lot of resources. Any old computer running WXP would work. If you encounter any software conflict, just re-install Windows to get a clean machine.

You should try to install the software on another computer first to verify the problem before trying multi-boot or virtual machine. These two approaches, though not difficult, require some expertise in installing Windows. There are many other advantages in running multiple instances of Windows on one computer, which has saved us many times in the past.

Which cuff should I used? The width of the cuff should be either 40% of the limb circumference (50% for neonates) or 2/3 of the upper arm length. The inflatable part of the cuff should be long enough to encircle 50-80%of the limb. The wrong size of cuff can cause erroneous readings. If the cuff size is in question, then use a larger cuff.

Make sure that the cuff edge falls within the range of mark <->. If it does not, use a larger or smaller cuff that fits better.

PatientLimb PerimeterCuff Width
Neonate6-11 cm4.8 cm
Infant10-19 cm8 cm
Child18-26 cm10.6 cm
Adult125-35 cm14 cm
Adult233 - 47 cm17 cm
Thigh46-66 cm21 cm

Will the insurance pay for the use of ABPM? This depends on the insurance. The most likely answer is yes for some medical conditions. Medicare has approved the use of ABPM under certain medical situations.

CPT code 93784 thru 93790 may be used for billing purposes, including:

ABPM CPT procedure codes
Ambulatory blood pressure monitoring; including recording, scanning analysis, interpretation and report.93784
Recording only93786
Scanning analysis with report93788
Physician review with interpretation and report93790
ABPM related IDC-9 codes
Elevated blood pressure reading without diagnosis of hypertension (The only ICD-9 code covered by Medicare)796.2
Essential hypertension401
Essential hypertension - Unspecified (Resistant)401.9
Hypertensive heart disease402
Hypertensive renal disease403
Nocturnal angina413.0
Ill-defined descriptions and complications of heart disease429
Orthostatic hypotension458
Hypotension, unspecified458.9
Hypertension complicating pregnancy, childbirth, and the puerperium642
Transient hypertension of pregnancy642.2
Mild or unspecified pre-eclampsia642.4
Unspecified hypertension complicating pregnancy642.9
Maternal hypotension syndrome669.2
Syncope and collapse780.2
Other Hypertension (Episodic, Labile, Postural)997.91

Further Readings