Fluid Pressure And Pressure Limiting; Response To Occlusions; Volume And Flow Rate Protection; Syringe Installation Features - Bayer HealthCare Medrad MRXperion Operating Manual

Operation Manual

4.3.7 Fluid Pressure and Pressure Limiting

The fluid pressure is measured by the system during the execution of a phase and ensures the protocol Pressure Limit is not
exceeded. Fluid pressure is dependent on the following:
Flow rate
Q
Fluid viscosity
Q
Fluid temperatures
Q
Attached syringes and connector tube
Q
Catheter type/size
Q
Pressure Limiting occurs when the measured fluid pressure exceeds the protocol Pressure Limit setting. If this occurs, the
system informs the operator of the condition and initiates Flow Rate Reduction for the Fluid Delivery phase to reduce the
fluid pressure.
4.3.7.1 Flow Rate Reduction
A slower flow rate is automatically initiated by the system to prevent the fluid pressure from exceeding the Pressure Limit.
The system will deliver the phase volume at this reduced flow rate. The fluid delivery phase will exceed the programmed
duration when Flow Rate Reduction occurs.

4.3.8 Response to Occlusions

When injecting into an occlusion, a stall condition or high pressure disarm results. A stall condition occurs when the actual
flow rate is less than 10% of the defined rate. If a stall or high pressure disarm occurs, check the fluid path for blockage and
inspect the syringes and connector tube for damage or kinks. If no issue is found, consider increasing the catheter size,
removing administration sets, or decreasing the flow rate.
If an occlusion occurs during KVO, the system will detect the condition after 4 or less KVO boluses fail to be delivered. (The
occlusion will be detected after 1 minute or less if the KVO interval is set to 15 seconds or after 5 minutes or less if the KVO
interval is set to 75 seconds.) Refer to

4.3.9 Volume and Flow Rate Protection

The system provides the following protection against over and under volume or flow rate conditions:
Warnings on the Safety Screen to remind the operator to check the protocol prior to the system being armed.
Q
On-screen indications of insufficient volume when the total programmed volume is greater than the amount of
Q
fluid in the syringe.
Injection monitoring to detect over flow rate or over volume conditions due to system faults. If either of these
Q
conditions is detected, the injection is stopped.

4.4 Syringe Installation Features


CAUTION
Mechanical Hazard - Minor or moderate patient and/or worker injury may result.
Ensure the syringe is properly snapped into the front of the injector head before injecting.
Q
Improper engagement or rotating syringe may cause the syringe to leak, become damaged, or to disengage from the injector head
Q
during the injection.
The system is designed with four features that decrease the time and steps to install and remove syringes to the injector
head. (For more information about configuration of these features, see
1.
Non-rotational orientation: When installing a syringe onto the injector head, alignment is unnecessary. Push the
65mL syringe into opening A and the 115mL syringe into opening B.
"Section 15.4 - Fluid Delivery Setup" for information about setting KVO intervals.
"Section 15.4 - Fluid Delivery Setup".)
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