Pulmonary Artery Catheters

(PA catheters)

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• Medical condition associated with heart failure or cardiogenic shock
• Post-operative monitoring for management of hemodynamics after cardiac surgery
• [Medications or IV fluids might be administered intravenously through the proximal port, a right ventricular pacemaker port, or a port through the introducer.]
• Continuous thermodilution measurement of cardiac output.
• Monitoring core body temperature [ancillary parameter associated with thermistor port].

• Understanding of procedure
• History of heart failure, COPD, head injury, cerebral bleeding risk
• Allergies to iodine, tape, Latex^®, ointments

• Informed consent (principle of autonomy)
• These are contraindications for positioning the patient in Trendelenburg position.
• Guide for selection of supplies to prevent allergic reaction

Steps

1. Wash hands.

2. Prepare pressurized and heparinized flush solution. (See procedure under Hemodynamic Principles).

3. Flush pressurized closed transducer tubing with luer-lok connections and ports.

4. Don sterile gloves, protective gown, and mask.

5. Assist with skin preparation.

6. Position patient in Trendelenburg position.

7. Assist physician or advanced practice  nurse with flushing PA catheter ports with sterile solution.

8. Connect the pressure line(s) to the distal and proximal ports.  Connect monitoring equipment and set scales and alarms for each parameter.

9. Level the transducers with the patient's phlebostatic axis and "zero" the transducers. (See Hemodynamic Principles.)

[Physician will apply topical anesthetic to insertion site, then use a needle and syringe with negative pressure to access the subclavian or internal jugular vein.  Next the physician will insert a guidewire through the needle, remove the needle, then insert a dilator and introducer “over” the guidewire.  Last, the physician will remove the dilator and the guidewire.  Then the pulmonary catheter will be inserted through the introducer catheter. A sterile sheath will be placed around the PA catheter and connected to the introducer catheter.]

10. The patient will be instructed to take a deep breath and hold it prior to the insertion procedure.

11. After the PA catheter has been inserted a few inches, inflate the balloon port.

12. Monitor cardiac  monitor and hemodynamic waveform of distal port during catheter insertion.

13. As the distal port "floats" through the right ventricle, make a recording of the waveform and record the systolic and diastolic pressures.

14. When the inflated balloon finally occludes a pulmonary artery, record PAOP reading and deflate the balloon passively.

15. Observe waveform and perform a dynamic response test (square wave test).

16. Record PA systolic, diastolic, and mean pressures.

17. Apply transparent occlusive dressing over insertion site.

Rationales

1. Prevention of nosocomial infections.

2. 1-2 units heparin/mL reduces risk of catheter occlusion through thrombosis.

3. Removal of ALL air bubbles promotes better waveforms and reduces danger of air embolism.

4. Arterial line insertion is a sterile procedure

5. Reduce normoflora microbes at insertion site.

6. Inflates internal jugular vein making it an easier target during catheter insertion. Decreases risk of air embolism.  (See contraindications above.)

7. Reduces risk of air embolism during insertion.  During this time, the nurse and the physician will test the balloon port, the thermistor port, and connect the pressure l

8. Connecting pressure lines allows the physician to monitor pressure waveforms and readings as the PA catheter is advanced through the cardiac chambers.

9. Phlebostatic axis approximates the level of the right atrium for establishing pressures in the circulatory system which enhances accuracy of readings.

[Sterile technique is used during the insertion procedure.  The physician and nurse should be wearing sterile gowns and masks.  The physician or whoever is performing the insertion must wear sterile gloves while working with the catheter.  The patient will be draped with a sterile field by the physician.  During insertion, it is the responsibility of the nurse to monitor the patient’s tolerance of the procedure and assess for any complications like dyspnea (possibly due to pulmonary embolism, pneumothorax) or tachycardia (due to stress, hypovolemia) or dysrhythmias (catheter placement).]

10. Increased intra-thoracic pressure reduces the risk of air embolism during exchanges of dilator and catheter over guidewire.

11. Inflation of the balloon port in the right atrium allows the catheter to "float" through the right ventricle into the pulmonary artery without irritating the ventricular wall.

12. Waveforms guide the insertion process as the tip of the catheter proceeds through the different  chambers.  Ventricular ectopy can occur as the distal port travels through the right ventricle.

13. Provides diagnostic information about right ventricular function.

14. Deflation of the balloon prevents pulmonary infarction.  Passive deflation means unlocking the balloon port and removing the syringe.  Aspiration of the balloon port can rupture the balloon and increase the risk for air embolism.

15. Determines location of the catheter and degree of waveform dampness.

16. Provides diagnostic data about left ventricular functioning.

17. Sterile procedure; occlusive dressing prevents blood stream infections.

(CVP)

(See PA Waveforms.)

(See PAOP Waveforms.)

Steps

1. Position patient supine with head-of-bed 0 – 60^o elevation.
2. Check level of transducer with phlebostatic axis.
3. During first assessment of shift, zero transducer to air.
4. Assess waveform for dampness.
5. Maintain tight luer lok connections and nonvented caps on stopcocks of pressure tubings.
6. Record PA systolic, PA diastolic, and PA mean pressures [35/14 (21)  35 is the systolic, 14 is the diastolic, and 21 is the mean pressure for this reading.]
7. Open the PA catheter balloon port.  Use the safety syringe that comes with the catheter kit.  While watching the waveform on the monitor, inject air into the balloon port until the waveform changes to PAOP.
8. Record PAOP reading.
9. Release the safety syringe and allow it to deflate passively.  If necessary, remove the syringe from the balloon port leaving the balloon port open to air.
10. Check the waveform to insure that it has changed back to the pulmonary artery waveform.

Rationales

1. Lateral positioning may result in variable pressure readings.  Supine promotes consistency of conditions.  Head-of-bed elevation has not been shown to alter pressure recordings significantly.
2. Insures accuracy of readings.
3. Insures representation of patient's BP on monitor.
4. Dampness may distort systolic and diastolic readings.
5. Prevents risk of air embolism.
6. PA pressures (systolic, diastolic, mean)
7. The catheter kit's safety syringe only allows the nurse to draw up 1.5 ml of air.  By injecting air into the balloon port until waveform changes to PAOP, the nurse will use the minimum amount of air to inflate the balloon.  This reduces the risk of hyperinflation of the balloon port resulting in balloon rupture or rupture of the pulmonary artery.
8. PAOP pressure value is a mean reading for the left ventricular pressure.  It also reflects the left ventricular end diastolic pressure.
9. Leaving the balloon inflated produces an obstruction of the pulmonary artery which will result in pulmonary infarction–similar danger to a pulmonary embolism.  Passively deflating the balloon prevents rupture of the balloon–aspirating from the balloon port will likely result in a balloon rupture making the balloon port no longer useful.  Limit balloon inflation to only 8-10 seconds when obtaining PAOP readings.
10. Verification that balloon has deflated.

• Central Venous Pressure:                                2 – 5 mm Hg   (3 – 8 cc H₂O)

• Right Ventricular Pressure (systolic):         15 – 30 mm Hg

• Right Ventricular Pressure (end diastolic):      < 6 mm Hg

• Pulmonary Artery Systolic Pressure:          20 – 30 mm Hg

• Pulmonary Artery Diastolic Pressure:           5 – 10 mm Hg

• Pulmonary Artery Mean Pressure:               10 – 15 mm Hg

• Pulmonary Artery Occlusion Pressure:         5 – 12 mm Hg

Problem

Intervention

1. Continuously Wedged Waveform

1. Assess the waveform.  Verify that it appears to be PAOP (wedged).

2. Remove PA balloon port safety syringe and make sure that balloon port is open to air (unlocked). 

3. Assist the patient in changing positions.

4. Ask patient to cough.

5. Never flush a wedged catheter. It may result in rupture of the pulmonary artery.

6. Notify critical care advanced practice nurse or physican STAT.  [Advanced practice nurse might loosen retaining screw for PA catheter and pull it back until PA waveform appears.] (Some medical centers allow the critical care nurse to perform this intervention.)

2. Catheter Lodged in Right Ventricle

1. Assess the waveform.  Verify that it appears to be characteristic of a right ventricle.
2. Assess the cardiac monitor.  PA catheter in the right ventricle often results in PVC's or ventricular tachycardia.
3. Inflate the balloon port with 1.5 ml of air using the safety syringe.  Doing so might "float" the catheter back into the pulmonary artery.
4. If waveform does not change to PA, then assist patient to change positions while balloon is inflated.  If waveform does not change, notify advanced practice nurse of physician STAT.  [Advanced practice nurse might advance the catheter or withdraw the catheter completely.]  (Some medical centers will allow the critical care nurses to withdraw the catheter until a right atrial (CVP) waveform appears.  Then the physician can decide whether to keep PA catheter in the patient and refloat it back into the pulmonary artery or discontinue the catheter.)  Leaving the PA catheter in the right ventricle can result in life-threatening ventricular dysrhythmias.

3. Rupture of Pulmonary Artery (overinflation of balloon)  Patient displays signs of hemoptysis or bloody aspirate during suctioning.

1. Notify physician STAT.  This is an emergency due to perforation of a pulmonary artery.
2. Maintain patency of airway.
3. Prepare to send blood specimens for CBC,coagulation studies and crossmatch.
4. Obtain a STAT portable chest x-ray.
5. Prevention is imperative!  Inflate balloon port only to the extent necessary to achieve wedge pressure.  Always use the safety syringe that comes with the PA catheter–it only allows a maximum of 1.5 ml of air to be injected.  Always assess waveform to insure that PA waveform is showing.  Limit balloon inflation to only 8-10 seconds when obtaining PAOP readings.  After PAOP reading, expel air from safety syringe and connect it to balloon port–this prevent accidental inflation and also loss of the safety syringe.

4. Potential for sepsis.

Guidelines for the Prevention of Intravascular Catheter-Related Infections

1. Hand Hygiene:  Thorough handwashing prior to insertion or handling of central venous catheters will reduce risk of nosocomial infections.

2. Maximal Barrier Protection:  The insertion of a central venous catheter should be done under sterile (surgical asepsis) conditions.  The clinician inserting the catheter should wear mask, cap, sterile gloves, and sterile gown.  The patient should be draped in a sterile field around the insertion site.  Assistants (e.g., nurses) should wear masks, protective gowns, and gloves while in the area–if the nurse will be working with the sterile equipment or supplies, the nurse should wear sterile gown, mask, cap, and sterile gloves too.

3. Chlorhexidine Skin Antisepsis:  Chlorhexidine has been shown to reduce more skin normal flora than povidone-iodine or alcohol as a skin disinfectant prep prior to insertion of a central venous line.

4. Optimal Catheter-Site Selection:  Rates of catheter-related bloodstream infections are lowest among catheters inserted into subclavian vein compared to internal jugular vein.  Femoral vein insertions should be avoided if possible due to the high rates of bloodstream infections associated with the inguinal area.

5. Daily Medical Review of Necessity of Catheter:  The medical physician should review daily the need for a central venous catheter with the goal of early removal as soon as the patient no longer needs the catheter.  The longer a catheter is retained, the higher the probability of bloodstream infection.  The nurse can bring this to the physician's attention during rounds as to whether any critical interventions like TPN or hemodynamic monitoring is occurring that needs a central venous catheter.

6. Replacement of Catheter:  Recent evidence suggests that the rate of infections are not significantly different when catheters are replaced every 72 hours or less. 

Bundle of Practices Related to Nursing Care:

1. All-Inclusive Catheter Cart or Kits:  Having a cart or kit that has all necessary equipment for procedures reduces the risk of contamination of equipment when additional items are added to a sterile field.

2. Hand Hygiene:  For all nursing procedures involving a central venous catheter (changing tubing, adding second infusion line, changing TPN solutions, IV administration of medication) the nursing care should begin with thorough hand washing with soap and running water to reduce the risk of nosocomial infections from other sources.

3. Site Care:  Maintain a well adhesive transparent dressing over central venous catheters.  Cath cares should involve scrubs of site with chlorhexidine during dressing changes.  Transparent dressings only need to be changed every 7 days.  Gauze dressings should be changed every 48 hours.  Anytime a dressing is damp, soiled, or coming loose, then it should be changed with a full skin prep prior to application of a new dressing.

4. Line Access:  The less frequently a central line is accessed from one of its ports (hubs), the higher the risk of a bloodstream infection.  Therefore, do not access a central venous catheter except for essential procedures requiring the central line.

5. Scrub the Hub:  When a hub on a central venous catheter infusion line is accessed, evidence does not support chlorhexidine over 70% isopropyl alcohol.  However, the duration of scrubbing the access hub influences the risk.  Performing a twisting scrubbing motion for 30 seconds with a disinfectant significantly reduces bloodstream infections.

6. Replacement of IV Administration Sets (Tubing):  Replacement of central line tubing every 72 hours is not associated with lower infection rates compared to 96 hours.  Replacement of tubing should be done with strict asepsis.  Special infusions like lipids or TPN may require more frequent tubing changes because the fluid medium is a greater risk for infection.

7. Appropriate Staffing and Nursing Workloads:  Evidence has indicated that the higher the nursing workloads or the more inadequate the staffing, the less time that is available for safe management of central venous catheters.

1. Wash hands.
2. Don nonsterile gloves, face shield, and protective gown.
3. Turn off monitor alarms for PA and CVP parameters.
4. Remove occlusive dressing.
5. Attach 3 ml syringe to proximal port.  Turn stopcock off to transducer and aspirate 3 ml blood.
6. Apply direct pressure 1-2 fingerwidths proximal to insertion site.
7. Remove arterial catheter covering site with a sterile 4×4 gauze.
8. Apply direct pressure over insertion site and 1-2 fingerwidths proximal to insertion site for 10 minutes.
9. Assess insertion site for bleeding or hematoma while applying pressure.
10. Assess distal circulation while applying pressure.
11. Apply a pressure dressing to the insertion site after hemostasis has occurred.

1. Reduce nosocomial infection risk.
2. Protect oneself from possible spurting blood during procedure.
3. Reduce anxiety provoking stimuli to patient.
4. Hold arterial line and catheter in one hand to insure that catheter does not become prematurely dislodged.
5. Aspiration of blood reduces the risk of thromboembolism from end of catheter.
6. The arterial catheter actually penetrates the artery proximal to the insertion site in the skin.
7. Sterile gauze reduces the risk of infection.
8. Arteries require more prolonged compression in order to facilitate hemostasis due to the greater arterial pressures.
9. Minimizes risk for bleeding.
10. Monitors circulation to the extremity due to the risk of thromboembolism.
11. Reduces risk for hemorrhage.

Pulmonary artery catheters are used to collect cardiac output assessments through thermodilution technique.  A PA catheter is required in order to collect this data.

Several hemodynamic parameters are determined by calculations  based on data generated from PA catheters.  Cardiac index (CI), Systemic Vascular Resistance (SVR), Pulmonary Vascular Resistance (PVR), and Stroke Volume (SV) are some of the fundamental parameters used in managing hemodynamic properties.

SvO₂ monitoring provides information about continuous venous oxygen saturation, a parameter reflecting the balance between oxygen supply and demand in the systemic circulation.