CENTRAL VENOUS MONITORING:
STANDARDS OF NURSING CARE IN CCTC (SONC)

1. Set-Up Hemodynamic Circuit
2. Maintain Accuracy
3. Maintain Closed System
4. Obtain Blood Samples
5. Change Dressings
6. Monitor Site

7. Analyze CVP
8. Document
9. Obtain Chest Xray
10. Obtain Access for Central TPN
11. Remove Central Line

STANDARD OF NURSING CARE

 1.

Set-Up Hemodynamic Circuit

Clinical Nurses in CCTC are responsible for the priming, zeroing, leveling, and maintenance of hemodynamic pressure monitoring circuits and for the assessment and monitoring of hemodynamic pressures and waveforms.

Clinical Nurses may flush hemodynamic monitoring circuits as required to maintain patency.

Use the distal port of a multi-lumen catheter for monitoring pressure, unless the quality of the waveform is better from one of the other lumens.

All central venous lines, including femoral venous lines must be connected to a closed pressure monitoring system at the time of line insertion, and have pressure and waveform monitored.

 1.

Clinical Nurses in CCTC have received additional education in the care of invasive monitoring circuits. Refer to Procedure for Hemodynamic Monitoring Circuits.

Waveform assessment is important to confirm that the line is venous versus arterial. Although CVP monitoring from a femoral venous line may not reflect the right atrial pressure, it can still be used to guide fluid therapy by following the trend.

 2.

Maintain Accuracy

Hemodynamic transducers are zeroed at each initial setup, with the air-fluid interface (stopcock above transducer) leveled to the mid-axillary line.

Transducer levels should be validated at the beginning of each shift, prior to each PWP or CVP measurement, following position changes, and prn to validate hemodynamic pressures.

Document level confirmation in the graphic record. Documentation is required at the start of each shift and q6h, prior to each CVP and PWP measurement, and following transducer repositioning.  PICC lines do not require routine pressure monitoring.

 2.

Zeroing eliminates the effect of atmospheric pressure on measured hemodyamic values.

Leveling eliminates the influence of hydrostatic pressure on the transducer. A transducer that is positioned below the patient's heart will produce falsely elevated pressures and a transducer positioned above the patient's heart will produce falsely low pressures.

PICC lines are not inserted for hemodynamic monitoring and are placed under fluoroscopy.

3.

Maintain Closed System

All stopcocks must have dead-end (non-vented) luer lock caps or luer lock connected infusions. This includes stopcocks located on transducers.

Hemodynamic circuits are changed with each new line and prn.

3.

To prevent accidental entry of air or contaminants. Accidental movement of a stopcock that does not have a dead end luer lock cap can result in hemorrhage/air embolus.

4.

Obtain Blood Samples

Clinical Nurses may draw blood from indwelling venous lines using a stopcock technique.

Clinical Nurses may draw central venous gases to determine Central Venous Oxygen Saturation (ScvO2), from central lines inserted via the subclavian or jugular sites.

Venous blood gases should be obtained at the time of central line insertion (including femoral venous lines), q 1 h during resuscitation or manipulation of vasoactive drugs until normalized, then q 4 h until vasoactive drugs are no longer required.

4.

See Procedure for Blood Withdrawal and Blood Gases Venous. Remember, that when you draw a blood sample from a central line with one or multiple infusions running through it, you must stop all infusions to draw the blood sample(s) to avoid contamination and inaccurate results.

Patients requiring vasoactive drugs are still in shock. Venous gases can be used to identify the adequacy of the cardiac output. Although femoral venous gases may not reflect the right atrial values, they can be used for trending.

5.

Change Dressings
Central line dressings are changed q 2 days (tape and gauze)and prn, when using Tegaderm(TM) transparent dressing change q 7days and prn when occlusivity is disrupted. Document date of change in the graphic record and kardex. Record any redness or abnormal findings in the AI record and report to the physician. See Procedure for Dressings: Arterial and Central Line.

Lines are changed prn for evidence of site infection or sepsis.

5.

Dressings of tape and gauze are change q 2 days and prn in critically ill patients to allow site inspection and to reduce bacterial colonization Skin condition, diaphoresis and site oozing necessitates more frequent dressing changes in critically ill patients.

It is acceptable and prefered LHSC Infection Control practice to use a Tegaderm TM dressing that can be changed q7days as per general hospital policy, as long as occlusivity is maintained.

The Centre for Disease Control does not recommend routine line changes.

6.

Monitor Site

Monitor site q 15 minutes following insertion, then q 1 h. Monitor for bleeding, IV connections and occlusivity of dressing. Monitor distal extremity for color, sensation, swelling and movement q 1 h. Document any finding not within normal limits in AI record.

6.

Bulky dressings can mask bleeding. Pressure dressings will not stop arterial bleeding.

Venous thrombosis or hematoma can compromise circulation to distal limb.

7.

Analyze CVP

Measure right atrial and femoral venous pressures from a waveforms that is printed and analyzed to identify the pressure at end-expiration and the base of the "V" wave.

Waveform analysis is identified on a paper recording for each right atrial pressure measurement. Paper recordings are placed in the clinical record, with the CVP measurement point identified on the printout.

If CVP is measured more frequently than q4h AND the CVP pressure has remained unchanged, CVP printouts may be posted q 4 h. If the CVP value has changed by > 3 mmHg or the waveform has changed from the last measurement, post the waveform in the clinical record.

7.

CVP measurements are obtained from a right atrial waveform. Femoral venous pressures do not reflect the right atrial pressure, but should have a waveform that is similar to a CVP. The pressures from the femoral vein will be different, however, pressure trends from the femoral vein can provide guidance reqarding fluid resuscitation.

The goal for right atrial pressure monitoring is to identify the pressure during end-expiration and end-diastole. Although the pre-C wave best reflects the end-diastolic pressure, it is often difficult to identify, reducing inter-rater reliability. For consistency, we measure the pressure during mid-diastole (during diastasis) because it is easy to find and reflects a pressure that is similar to the pressure at end-diastole.

Posting the waveform in the clinical record allows other members of the team to compare multiple pressure readings with better precision, allowing for more accurate interpretation of trends and signficance.

8.

Document

Identify CVP as per item #7 and document pressure in the graphic record.

Record venous oxygen saturation in the hemodyanmic section of the graphic record.

Assess catheter patency and document in the intravascular line section of the flow sheet at the start of each shift and q 4 h.

Document intravenous infusion in the 24 hour assessment record and sign for all infusions in the MAR, including heparinized flush solution.

Record IV infusion volumes in the fluid balance record.

Record vasoactive drug doses in the graphic record section of the flow sheet.

Document dressing changes in flow sheet. Star and DAR abnormal findings.

8.

As per hospital policy.

9.

Obtain Chest Xray

Obtain chest xray daily (unless otherwise ordered) and following all central venous catheter insertions.

9.

To identify complications including: pneumothorax, hemothorax, hydrothorax, catheter kinking, catheter placement (e.g. right atrial placement of CVP catheters or distal placement of right heart catheter), pulmonary infarction or hemorrhage.

10.

Obtain Access for Central TPN

New lines should be inserted for initiation of central TPN (vs using an existing line). Exceptions may be made by the CCTC Consultant if the risk of line insertion exceeds the risk of infection.

10.

Central TPN supports the growth of infection, particularly fungemias.

11.

Remove Central Line

Clinical Nurses may remove central venous lines in CCTC, with an order from a physician. Document removal in the intravascular device section of the graphic record.

See Procedure for Removal of Central Venous Line.

11.