What are the units conversion values for a Millar Mikro-tip Pressure Catheter when used with a ADInstruments Bridge Amplifier?

The sensitivity specification for a Millar Mikro-tip Pressure Catheter is 5 µV/V/mmHg. When using a Mikro-tip Pressure Catheter with an ADInstruments Bridge Amplifier the AEC-10D Catheter Interface Cable will be required.  This cable configures the Bridge Amplifier to excite the catheter with 5 Volts of excitation voltage, and sets the output of the catheter to be 25 µV/mmHg.  Some possible Units Conversion values for this equipment configuration are listed below (but it is always suggested to use a manometer to calibrate the catheter):

  • 7.50 mV -> 300 mmHg
  • 5.0 mV -> 200 mmHg

  • 2.50 mV -> 100 mmHg

  • 1.25 mV -> 50 mmHg

  • 625 µV -> 25 mmHg

  • 250 µV -> 10 mmHg

Note: the catheter will need to be pre-soaked and warmed prior to use as outlined in the catheter owner's guide.  Additionally, any offset present in a catheter's output will need to be removed prior to each use via the zeroing function in LabChart's Bridge Amp settings dialog.