Power Injector instructions

 

Detailed information for the power injector is available in the operator’s manual kept under the touch screen console.  An educational video is also in the library.  These should be reviewed prior to independent use of the power injector.  The following list of instructions is a summary.

 

  1. While the subject is having the IV placed get 30 cc of saline and a 20cc vial of Magnevist (Gd-DPTA).  These are usually available in the patient care area.  Injector syringes are kept in the 4T hardware room.

 

  1. The power switch for the injector is located on back right-hand side of the power supply box, beneath the console. The green light on the front of the power supply will illuminate.

 

  1. Following this the console should be turned on by using the button on the right side of the screen.  This should turn blue once power is on.   Touching the screen or the power injector head controls may result in an error message, if done prior to the injection mode screen being displayed.  Simple turn of the power and start again.

 

  1. Once the system is ready, the injection mode may be selected by pressing the ‘injection mode key’ at the bottom of the console touch screen.  This will give several options.  Select the single phase injection with saline flush.  ‘A’ is for the contrast injection, and ‘B’ is the slain flush.  (It is likely that this setting will already be on the screen, because the injector always uses the last injection mode as its default).

 

  1. The administration rates can be changed by touching the ‘flow’ button for ‘A’ and ‘B’, and dialing in the appropriate volume using the slide bar near the bottom of the screen.  Generally we administer contrast and saline at 2cc/s. 

 

  1. The pressure at which the injector will stop administering contrast or saline, can be changed using the ‘PSI’ button on the console touch screen.  I generally keep this < 100 PSI.  Pressures above this may be due to some type of obstruction impeding the flow; likely a clamp being left on, but may also be due to a poorly placed IV catheter.

 

  1. Once the appropriate volumes are set on the console touch screen, the power injector head should be placed in the ‘zero’ position.  This is done by holding down the silver buttons found at the end of each syringe holder well.  While the silver button is depressed the ‘syringe size indicators’ should read 60cc.  While holding down the button, advance the powerhead ram to the ‘zero’ position by simultaneously pressing the forward and accelerator buttons. The ram will stop when zeroed.  The ram can then be returned to the filled position using the accelerator and reverse button. (When this zeroing is not done, the volumes in the syringes and those displayed on the console may differ significantly).

 

  1. After you know the subject has a working IV, the syringes can be filled.  I generally wait until the IV is in place to avoid wasting the contrast and equipment should placement not occur.   Remove the syringes from there sterile packaging carefully, so as to avoid contamination.  Remove the needle cap, fill the syringe with approximately 10cc of air.  Remove the vial cap, avoiding contact with the rubber stopper of the vial.  Holding the syringe with the needle upright, gently push the needle through the stopper so that only the thin distal position of the needle is in the stopper.  Pushing the thicker portion of the needle into the stopper will result in leaking around the needle.

 

  1. Gently expel 5cc of air into the vial, and then pull back on the syringe plunger.  Repeat until all the contrast is removed from the vial and you have 30 cc of saline in the syringe.

 

  1. Repeat the previous steps with contrast.  It is unlikely that you will need more than 20 cc of contrast for a subject. 

 

  1. Make sure that any large bubbles are expelled from the syringe.  (Tiny bubbles are likely of no consequence and it is difficult to expel them all).

 

  1. Attach the contrast syringe (the one with 21cc) to the IV tubing with the blue reflux valve.  This valve keeps saline from refluxing into the contrast syringe during injection.

 

  1. Attach the saline syringe to the other side of the IV tubing. 

 

  1. Inject until contrast is just beyond the intersection.  Then inject contrast until a few drops of fluid drips from the distal end of the tubing.  This ensures that all air has been expelled from the system.

 

  1. Carefully insert the contrast syringe into the ‘A’ injection well and saline in the ‘B’ injection well on the power injector head.  The rams should then be forwarded until they just contact the plunder of the syringe.  (Depressing the forward button without simultaneously depressing the accelerator buttons allows for fine tuning).

 

  1. Once the syringes are placed, double check that all air has been expelled from the system.  The ‘air check’ button (the one with the eye) on the power head is then pressed.  Two blue lights on the top of the injector head should illuminate.  The injector is ready.

 

  1. When the patient has been placed in the magnet, attach the distal end of the injector tubing to the patient’s IV tubing.  Remove all clamps from the patient IV tubing.  Check for flow in the tubing be injecting a few cc’s of saline manually, using the ‘B’ syringe forward button.

 

  1. Returning to the console room, there should be green start button noted on the touch screen.  If not the ‘air check’ key on the power head has not been pressed.

 

  1. Once the high resolution image is completed, the injection can be started by pressing the green start button on the touch screen or the injector powerhead (unlikely), or the button on the remote controller. 

 

  1. The pressure of the injection, time, and volume remaining will be displayed during the injection. 

 

  1. Should there be any concerns, the injection should be aborted immediately by pressing the stop button on the touch screen or the injector powerhead.

 

  1. Upon completion of the scan, reverse the rams and remove the syringes.  The syringe may be thrown in the trash; needles should be thrown in a sharps container.

 

  1. Turn off the touch screen and the power supply.

 

  1. In the event of medical emergency remove the patient from the magnet room, get the nurse, call 911, and follow basic cardiac life support procedures until help arrives.