After review/study of the CCNS Orientation manual and attendance at the CCNS orientation and skills laboratory, the learner will be able to:

  1. Collect all necessary equipment/supplies to set-up a single or triple pressure transducer system.
  2. State the correct solution used at for flush bag.
  3. Correctly assemble single or triple pressure transducer system.
  4. Correctly level and zero the transducer.

PURPOSE: To monitor one or more pressure continuously using a single or triple transducer pressure tubing system.

Special Equipment

  • 250cc NSS or Heparin flush solution
    Single or multiple disposable transducer with monitoring kit & in-line syringe
    Pressure monitoring module/cable
    Transducer mount/ IV pole
    Pressure bag with gauge
    ECG monitor with pressure monitoring module


    ACTION                                                  RATIONALE

    1. Assemble equipment. Wash hands. 1. Reduces transmission of microorganisms.
    2. Plug transducer cable into monitor 2. For signal transmission to oscilloscope.
    3. Set scale for pressure being measured. 3. Necessary for visualization of complete waveform and to obtain accurate readings. PAP usually on 40 mm Hg scale, CVP on a 30-mmHg scale, and arterial pressure according to patient’s systolic BP.
    4. Obtain 250cc NSS or 250 U. Heparin/ 250cc NSS for flush bag. 4. Need physician’s order for type f solution & document on medication sheet and I &O’s section.
    5. Label IV bag, tubing and time strip. 5. Validates times and promotes compliance with established standards.
    6. Remove tubing/transducer from package, spike bag, invert and squeeze while pulling on fast flush device to remove air from bag. 6. Prevents accidental entry of air into tubing and patient via microbubbles that may dampen tracings and readings.
    7. Tighten all tubing connections; maintain aseptic technique throughout assembly. 7. Connections will be loose from their sterilization process. Reduce risk of infection.
    8. Open IV roller clamp, squeeze the drip chamber and fill to about 1/3 . 8. Prime drip chamber. Overfilling will prevent nurse from visualizing the flow during flushing.
    9. Flush entire system, including transducer, all stopcocks, and pressure tubing. Replace any vented caps with Leur-lok or "deadend" caps, and tighten securely.

    10. Place flush solution in a pressure bag and pump up pressure to 300 mmHg.

    9. Reduces risk of micro air bubbles, dampened waveforms, & inaccurate readings. Prevent fluid leaks and reduce risk of infection.

    10. Pressure is required to maintain flush device and at 300 mmHg will deliver 3 cc/hr.

    11. Level the transducer:

    a. Position patient @ 0 to 45-degree angle.

    b. Locate phlebostatic axis- level to right atrium, at the fourth intercostal space midaxillary line.

    c. Place the carpenter’s level between the phlebostatic axis and the air-fluid interface of the transducer. Move the transducer up or down on the IV pole until the bubble is centered.

    11. Ensures accuracy of heart pressure readings.

    Serves as a reference point for consistency.

    12. Zero the transducer:

    a. a. Open stopcock located on air-fluid interface to air (remove cap maintaining aseptic technique and close to the patient).

    b. Push and release the zeroing button on monitor or handheld device. Observe the digital reading to fall to a "zero" value display.

    c. Turn stopcock back to open system to patient. Ensure deadend cap reapplied.


    a. So monitor can use atmospheric pressure as a reference for zero.

    b. Zeroing negates the effects of atmospheric pressure so that only pressure values that are measured are the ones within the blood vessel or within the heart.

    c. To resume monitoring the patient.

    13. Connect tubing to patient. (The first cable outlet in the Marquette system is set for arterial monitoring.) If the system is set up prior to connection to patient, re-zero after patient connection. .
    14. Activate the flush valve mechanism and evaluate the square wave test. 14. Inadequate square wave test is an indicator of unreliable readings.


    1. Maintain sterile technique throughout preparation of system.
    2. Check for accurate readings; rebalance and zero as necessary and at least once a shift, at the beginning of the shift.
    3. Be sure that transducer is at level of the patient’s right atrium prior to taking readings.
    4. Check that all connections are secure.
    5. Ascertain that all stopcocks are in proper position.
    6. Free all tubing and cables from potential pressure of kinking points.
    7. Respect electrical safety guidelines for invasive monitoring.
    8. Maintain 300 mm Hg pressure in inflatable pressure bags during pressure monitoring.



    1. Check adequacy of tracing by flushing the system with flush mechanism and looking for the square wave tracing during the flush.
    2. Check for arterial line, central venous, and pulmonary artery pressure curves, adjust scale if needed, trouble shoot if dampened.
    3. Tubing/bag/dressing changes IAW Infection Control Manual:

    a. Flush bag q. 24 hours or with every new site

    b. Pressure tubing down to site q. 72 hours or with every new site

    c. Dressing (use Central Line Protocol) q. 72 hours or when loose





    Air emboli

    Tubing separation

    Equipment malfunction


    This page last updated 07/25/10

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