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LSUHSC Shreveport
Radiology Department
Proc 13.17
Operating Guidelines for the Medrad Stellant D Injector
Purpose: In order to minimize extravasations and maintain imaging quality the
following guidelines and instructions shall be used.
Guidelines:
1. Use a 20 gauge or larger IV catheter over needle (a 22 gauge may be used
with slower flow rates).
2. The preferred location for venipuncture is the medially located antecubital
vein.
3. Have at least ½ inch of the catheter positioned in a good vein with rapid
backflow.
4. Use a 60-96 inch coiled low pressure tube securely attached to the
catheter. The coiled tubing reduces motion effect during table
incrementation.
5. Instruct the patient to communicate immediately any pain or change in
feeling during the injection.
6. If possible, instruct the patient to put his or her arm vertically above the
shoulder with the palm of the hand on the ace of the gantry during
injection. This allows for uninterrupted passage of injected contrast
through the axillary and subclavian veins at the thoracic outlet.
7. A small volume test injection of contrast or saline may be utilized to
confirm venous assess. A trained professional should remain by the
patient during the initial stages of the injection palpating the venous access
site to ensure proper placement of the I.V. catheter. If focal pain, swelling
or signs of extravasation are noted, the injection should be stopped
immediately.
8. Central lines and hep-locks should only be used in accordance with
hospital policy guidelines.
9. Adhere to all instructions, warnings, and cautions listed for the specific
products being used.
Injector Operation
DISPLAY CONTROL PANEL
1. INJECTION PHASES: First phase can be Test Inject, Contrast, or
Saline. Test Inject parameters are programmable in the SETUP
SCREEN. Six phases are available for programming. If more phases are
required, press the triangle below the first phase, and Select Contrast A,
Flush B, Hold, or Pause.
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LSUHSC Shreveport
Radiology Department
Proc 13.17
2. Flow Rate – 0.1 to 10 ml/sec, Volume – 1 to 20 ml, Pressure Limit – 50
to 325 PSI- Press SET to program.
3. DELAY- programmable to 1 to 99 seconds. Press SET to program.
Emits 5 beeps when delay is complete: Scan Delay, Inject Delay, No
Delay
4. Programmed Volume and Total Duration is displayed on the screen.
5. Syringe icons indicate volume remaining in the syringes. A=Contrast
- green, B+Saline-blue.
6. Press PROTOCOL LOCK on screen.
7. PROTOCOL LOCK must be ON to ARM from the injector head.
SYRINGE INSTALLATION AND LOADING
1. Place the injector head in an upright position with the pistons fully
retracted.
2. Syringes are sterile and for single use only. Patient injury can result
from leaks or ruptures during an injection. Use only MEDRAD
disposable products, or use catheters and connectors with pressure
ratings that are compatible with this system. Inspect syringe packaging
for expiration date and package integrity. Install syringes by inserting
quickly and firmly in one motion. Installing the syringe slowly can result
in an error message. Piston will automatically advance to the front of the
syringe.
SETUP:
1. Using sterile technique, attach the sterile loading device and load the
syringes by pressing AUTOLOAD and FILL A and/or FILL B within 10
seconds. The syringe will load the volume programmed at the Main
Screen.
2. Increase or decrease the volume by pressing the +/- key.
3. Manually load the syringe by pressing MOVE PISTON to activate the
forward and reverse load strips.
4. Expel any air from the syringes using the manual knobs or load strips.
5. Attach LPT with PRIME TUBE attached to the patient end of the tubing.
6. Select PRIME to fill the LPT with contrast or saline – configurable in the
SETUP SCREEN or use manual knobs or load strips.
7. Patient injury can result from high contrast temperature. Do not use the
syringe heat maintainer if the fault indicator light is on.
8. It is recommended that contrast be stored in a heater at 35° C before
loading it in a syringe. Once contrast is loaded, snap the heat maintainer
over the syringe to maintain contrast temperature.
9. Inspect the syringe, tubing, and FluiDots, confirming that all air is
expelled, remove PRIME TUBE, turn injector head down, and connect
LPT to patient ensuring an air-free connection.
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LSUHSC Shreveport
Radiology Department
Proc 13.17
10. FluitDots: View looking through the syringe jacket at a light source.
Empty syringe – dots appear as narrow elipses
Full syringe – dots appear larger and almost round.
11. Air embolism can cause death or serious injury to the patient.
Patient injury could result from high flow-rate venous injections.
Patient injury could result from inadvertent aspiration.
Extravasation can cause injury to the patient. Acknowledge that air
inspection has occurred by pressing CHECK FOR AIR. If CHECK FOR
AIR is not pressed at the injector head, the system will request
confirmation that all air was expelled as part of the arming procedure.
INJECTION PROCEDURE
1. Press ARM on the injector head or the Main Screen.
2. Ensure there is sufficient volume to complete the protocol, insufficient
volume is indicated with a message at the Display Console or flashing
indication at the injector head.
3. Press ARM twice at the injector head to proceed with the remaining
volume.
4. Armed Indication Lights – Contrast =green, Saline=blue, will flash when
the injector is armed or on hold and will be solid when injecting.
5. Initiate the injection at the patient side.
6. Injection View – configurable at the Set-Up screen. Volume Remaining
decrements and Delivered Volume increments.
7. Phase – as the phase is activated, it is highlighted, elapsed time and
current
8. Phase is in status window.
9. Pressure Graph – displays the syringe pressure developed during an
injection.
10. ABORT: Press any button on the head or display except
START/HOLD. Pressing START/HOLD during an injection will hold
an injection up to 20 minutes.
11. Injection Complete – summary of parameters selected and delivered are
shown. Elapsed time will continue until
OK is pressed.
12. Syringe Removal – twist syringe counterclockwise with tubing connected
and discard following local guidelines. The piston will automatically
retract.
STORE/RECALL/DELETE
1. STORE- enter desired parameters, press STORE. Title the protocol
using keypad, press ENTER. 32 protocols can be stored in memory.
2. RECALL – press RECALL, press protocol title, press OK.
3. DELETE- press RECALL, press protocol title, press DELETE.
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LSUHSC Shreveport
Radiology Department
Proc 13.17
DISPLAY CONSOLE KEYS
1. SETUP – identifies configurable items and displays values.
2. HELP – information on system operation and service.
3. RESET- replaces all programmed phases, with factory default settings.
SYSTEM MALFUNCTION MESSAGES
If a system malfunction appears:
a. Immediately remove power and disconnect the patient from the
system.
b. If a fault message cannot be corrected, and/or the system is not
Operating properly, DO NOT USE the system. Call MEDRAD
Service.
c. Routine inspections and maintenance will ensure continued
performance and reduce equipment malfunction. MEDRAD, Inc.
recommends complete calibration and performance check annually.
CLEANUP
1. SHOCK HAZARD. Disconnect the system from line power when
cleaning.
2. Do not immerse any part of the injector or allow liquid to enter the
enclosure.
3. Wipe the system with a soft cloth, warm water and a mild disinfectant.
For all body-fluid spills, follow institutional decontamination procedures.
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LSUHSC Shreveport
Radiology Department
Proc 13.17
STELLANT PRESSURE MONITOR HELFUL HINTS – 203473 Rev. A.
CONDITION# DESCRIPTION POSSIBLE CAUSES POSSIBLE ACTIONS
Condition #1 The graph is the typical
shape, but the pressure
is higher than normal.
The pressure required to push
the contrast media through
the disposable system is
higher than normal, which
means there is a greater
restriction to fluid flow.
Check to insure the syringe
heater is functioning
normally. As long as the
“Possible Causes” listed are
of no concern, then no
action is necessary.
Greater restriction can be
caused by any of the
following:
* Higher viscosity of the
contrast media
(more grams of
iodine/higher
concentration, or lower
temperature of
of the contrast media/not
heated.
* A smaller gauge catheter is
being used.
* An additional disposable is
in the fluid
path causing a greater
restriction to the
flow of fluid (extension
tube, stopcock,
check valve, IV extension
set).
* Defective syringe (under
lubricated).
Condition #2 The graph is the typical
shape, but the pressure
is lower than normal
The pressure required to push
the contrast through the
disposable system is lower
than normal, meaning there is
As long as the “Possible
Causes” listed are of no
concern, then no action is
necessary.
less restriction to fluid flow.
Lower restrictions can be
caused by any of the
following:
* A lower visocity contrast
media (less
grams of iodine/lower
concentration,
or higher temperature of
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LSUHSC Shreveport
Radiology Department
Proc 13.17
contrast
media/heated).
* A larger gauge catheter is
being used.
* Fewer disposables in the
fluid path (lack
of extension tube, stopcock,
checkvalve,
IV extension set).
Condition #3 The graph and injection
start out normal, but
level off to a less than
expected peak pressure.
An inappropriate pressure
limit may be selected. If a
lower pressure is selected
than what is required to
deliver the flow rate, the
injection will start out
normally for the first few
seconds. However, as soon
as the pressure limit value is
achieved, the flow rate will
automatically decrease to
Check to see if the Pressure
Graph is approaching the
dotted horizontal line
(pressure limit setting). If it
is, the injector is pressure
limiting and causing this
condition. See Pressure
Limiting” in the Operation
Manual for a thorough
discussion of causes and
resolution.
keep the system from
exceeding the selected
pressure limit.
Note: Medrad makes no claims about the information on the Pressure Monitor Graph
other than it is a graphic representation of the force required to move the syringe plunger,
which closely approximates the pressure developed in the syringe.
CONDITION# DESCRIPTION POSSIBLE CAUSES POSSIBLE ACTIONS
Condition #4 At the start of the
injection, the
Pressure Garph
signal
immediately
rises straight up
and hits the
pressure limit
setting (dotted
horizontal line).
The fluid path may be
occluded (after reaching a
“High Pressure Disarm”.
Stellant will automatically
terminate the injection).
Total occlusions may be
caused by one of the
following:
* A closed stopcock
* An IV extension set with
Consider putting the
injector on hold and
investigating. There is a
high probability that no
contrast media is being
injected into the patient.
the clamp
closed off
* A defective disposable
(fluid will not
flow through it).
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LSUHSC Shreveport
Radiology Department
Proc 13.17
Condiiton #5 The injection is
proceeding
perfectly normal,
but during the
injection, with no
programmed
decrease in flow
rate, the Pressure
Graph sharply
drops to baseline,
but no error
messages appear
on the screen.
Note: If a
multilevel
injection is
programmed,
and the flow rate
is programmed
to decrease, then
the pressurewill
also drop at that
time.
Condition #6 The pressure
buildup to the
expected peak is
taking longer
than typical
,
even thought he
injector is
injecting
normally.
If the injector is still armed
and injecting at a constant
flow rate, but the Pressure
Graph drops sharply to
baseline: Stop the injector
immediately and
investigate. The pressure in
the syringe has sharply
dropped and through the
piston is moving forward
and should be developing
pressure. Possible causes:
* The Low Pressure
Connector
Tubing, extension set, or
catheter
has burst or disconnected
from the
fluid path (fluid is
running on the floor).
* The syringe may have
failed. Fluid is being
forced around the syringe
plunger instead of
out the end of the syringe
(fluid is running on
the floor).
Due to operator error, the
syringe may contain a large
amount of air (example:
half air, half fluid). It is
easier to compress air, than
to push fluid through a CT
disposable system, so the
injector is initially
developing less pressure as
it compresses the air.
If the injector is still
injecting (arm light solid
and manual knob on the
back of the head turning),
consider aborting the
injection. There is a high
probability that fluid is
running on the floor.
Stop the injector
immediately and
investigate.
Check the fluid path for
air.
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LSUHSC Shreveport
Radiology Department
Proc 13.17
Condition #7 When the
injection starts,
almost no
pressure buildup
is witnessed,
when a buildup
was expected.
Due to operator error, there
may be no fluid in the
syringe (you could be
injecting air). The injector
will experience almost no
resistance to moving the
syringe plunger forward
with an empty syringe.
Stop the injector
immediately and
investigate.
Check the fluid path for
air.
Note: Very slow injections
through large disposable
sets will require and display
very little pressure. This is
normal. What is being
described above is a
condition where a buildup
of pressure was expected,
and none was witnessed.
OR: You may have two
syringes on the injector,
only performing a single
syringe injection, and the
LPCT may be connected to
the wrong syringe.
Condition #8 At the end of a
normal injection,
the pressure
graph does not
immediately
drop to zero.
Stellant is designed to inject
all of the contrast in the
syringe to help minimize
contrast waste. Sometimes
in the process of doing this,
the piston pushes against
No action. This is normal
operation.
the front of the syringe as it
squeezes out the last drops
of fluid. This in turn
generates pressure, which is
displayed by the Pressure
Graph. This pressure
reading should drop to
baseline after about 50
seconds.
NOTE: Medrad makes no claims about the Pressure Monitor Graph other than it is a
graphic representation of the force required to move the syringe plunger, which closely
approximates the pressure developed in the syringe.
Written: 1/19/2007
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