When monitoring invasive blood pressure, routinely inspect the catheter and/or pressure line for
leaks after zeroing, and always follow the pressure transducer/catheter manufacturer's use
Zeroing the Pressure Transducer
The transducer must be zeroed prior to the MRI examination after the transducer is in its
final setup position. Moving the transducer after zeroing may cause a measurement offset to
occur. Otherwise, inaccurate patient pressure readings may result.
To avoid inaccurate pressure readings, the monitor requires a valid zero. Zero the transducer in
accordance with your hospital policy (at least once per day). You must perform a zero:
To zero a pressure transducer
Refer to the appropriate procedure according to the patient type and application:
P1 and P2 Waveforms and VS Boxes
Invasive blood pressure measurements (P1 and P2) are displayed as waveforms (trace E and trace
F, respectively) in the VS trace area of the screen and as numeric information in the P1 and P2 VS
boxes. Other data, including P1‐ and P2‐related alarm information, are also provided in these
areas of the screen, as detailed below.
8‐16 Monitoring Invasive Blood Pressure
when you use a new transducer or tubing,
every time you reconnect the transducer cable to the monitor, or
if you think the monitor's pressure readings are not correct.
Adult / Pediatric—see page 8‐7.
Neonate—see page 8‐12.
Expression MR400 Instructions for Use