II. Pulmonary Artery Pressure Monitoring Flashcards
The PA catheter is also known as a:
Swan-Ganz catheter
The Swan PA catheter is used as a ____ procedure to assess critically ill patients
Diagnostic
The PA catheter is most commonly inserted through the ____ vein.
Right internal jugular
The PA catheter is ultimately placed into the ____ in order to estimate____.
- Pulmonary artery
- Left ventricular, preload and functions
Capabilities of the PA catheter include:
- Measures right heart filling pressures
- Estimates left heart preload and function
- Estimates cardiac output (themodilution)
- Evaluates, heart valves, shunts and pulmonary vascular resistance
Pulmonary catheter, wedge pressure (PCWP) is correlated with ____.
Left ventricular End diastolic pressure (LVEDP)
LVEDP gives an estimation of ____.
LV preload & function
not always a direct indicator, but a reasonable estimation
4 Major indications for pulmonary arterial catheters:
- Cardiac disease.
- Pulmonary disease.
- Complex fluid management/hemodynamic instability
- Specific surgeries.
What are a few specific surgeries that are indications for PAC?
- Aortic cross clamping.
- Hepatic or heart transplantation.
- CABG
Absolute contraindications for PAC:
- Right atrial or right ventricular mass.
- Tricuspid or pulmonary stenosis.
- Mechanical tricuspid, pulmonary valve prosthesis
Relative contraindications for PAC:
- Recently placed pacemaker or defibrillator wires (w/i 6 weeks)
- Left bundle branch block (risk of complete AV block)
- Severe coagulopathy.
- Significant thrombocytopenia.
- Infection at cannulation site.
What is the most common complication of PAC insertion?
Arrhythmia
Induced right bundle branch block can cause:
Complete AV block if left bundle branch block is present
What may the PA catheter become entangled with?
Chordae Tendineae
A heparin coated catheter may be used to decrease risk of thrombosis. How long is this effective for?
Up to 72 hours
What two factors can precipitate pulmonary infarction pertaining to a PA catheter?
- Distal placement.
- Prolonged balloon inflation.
What is the mortality rate associated with pulmonary artery rupture?
41 to 70%
What are the risk factors associated with pulmonary artery rupture?
- Hypothermia.
- Old age.
- Cardio pulmonary bypass
- Pulmonary hypertension.
- Female.
- Anticoagulation.
The standard pulmonary artery catheter is what size and length?
7.5 Fr
110 cm
What is the maximum balloon volume for a PAC?
1.5cc
what is the incident of pulmonary artery rupture when placing PACs?
0.03-1.5%
What is the most common number of ports on a PA catheter?
Five
What portion of the PA catheter allows us to transduce the pressures (PA & Wedge) as the catheter is floated through the heart?
Distal lumen hub (yellow)
What portion of the PAC contains temperature wires designed to measure the temperature of PA blood?
Thermistor Connector
How far is the thermistor located from the distal end of the catheter?
Approximately 4 cm
The volume infusion port (white) is located how far from the distal tip of the catheter? Where is it situated within the heart?
- 19cm
- RV
The proximal injectate port (blue) is located how far from the distal tip of the catheter? Where is it located within the heart?
- Approximately 30 cm
- Right atrium
Which PAC port is used to estimate the CVP?
Proximal injectate port (blue) situated in the right atrium
Thin black dashes are equal to ____ cm
10
One thick, black dash is equal to ____ cm
50 cm
What are the colors for arterial, pulmonary artery, and CVP lines on the transducer?
- Arterial is red
- Pulmonary artery is yellow
- CVP is blue
all three must be flushed, zero, and labeled prior to insert
T/F: fill the balloon before entering the right ventricle.
True
T/F: always deflate the balloon before withdrawing the catheter.
True
Over what time Should the balloon be inflated?
Slowly over three seconds
T/F: If PCWP wave form is noted, continue inflating the balloon.
FALSE, adjust the catheter position
T/F: the balloon should never remain inflated once placed correctly in the pulmonary artery.
True
For what reason is the PA catheter inflated intermittently once placed in the pulmonary artery?
To check the PCWP
Steps in order to insert the pulmonary arterial catheter:
- Maintain Sterility.
- Flush all ports before insertion. (Distal to Proximal)
- Test the balloon and integrity (attach the PA and CVP pressure cables and zero)
- Connect the distal port to the transducer (this allows visualization of waveforms)
- Advance the PAC through the introducer sheath (previously placed) and into the IJV.
- At 20 cm, the distal tip should enter the right atrium, and a central Venus tracing is seen.
- The balloon is inflated with 1.5 mL of air (once in RA at 20cm; here pressure is usually less than 5 mmHg).
- The catheter is advanced to about 30 cm, a sudden increase in the systolic pressure (~25 mmHg) indicates a right ventricular location.
- entry into the pulmonary artery occurs at about 40 to 45 cm, and a sudden increase in diastolic pressure (~10mmHg) is noted (systolic remains ~25 mmHg). This increase in diastolic pressure occurs due to closure of pulmonary valve
- At about 45 to 50 cm a pulmonary capillary wedge pressure weight form is seen.
- Deflate the balloon to see the pulmonary artery tracing (waveform) re-appear.
At what depth should the distal tip enter the right atrium, creating a central venous tracing?
20cm
At what depth is the distal tip located within the right ventricle, coinciding with an increase in systolic pressure?
30cm
Entry into the pulmonary artery occurs at what depth on the PAC, coinciding with an increase in diastolic pressure?
40-45cm
At what depth should a pulmonary capillary, wedge pressure (PCWP) waveform be seen?
40-45cm
CVP pressures in the right atrium
0-6 mmHg
PCWP is normally ____ mmHg
4-12 mmHg
The final resting place of the pulmonary arterial catheter is where?
- Wedged into smaller pulmonary capillary of the pulmonary artery.
- annotate this depth.
- Deflate balloon.
- Pull back three or 4 cm (leave here in PA)
- When we want to check PCWP, re-inflate, balloon again, and advance to previously annotated depth.
- never leave balloon inflated, this will cause pulmonary infarction!
PCWP is an indirect measurement of ____.
Left Atrial Pressure
the whole point of using the PAC
What can the side port on the introducer sheath be used for?
Rapid infusion of fluids
Wedged waveform appearance:
- lack of waveform, more linear in appearance
PAC must be inserted into what West zone?
3
What can be done if the PC will not float into the right ventricle?
- This is possibly due to tricuspid regurgitation.
- Fill the balloon with 1.5 mL of normal saline and reposition the patient left side down.
What should we do if the PAC will not float into the pulmonary artery?
- This is usually due to a coiled PAC in the right ventricle or possibly pulmonary hypertension
- Withdraw the PAC and advance again, slowly and continuously, reposition the patient left side and head up.
What should we do if the PAC entered the coronary sinus?
- This may happen with a dilated coronary sinus (hi CVP, tricuspid, regurgitation, cardiac anomalies)
- To confirm, location is coronary sinus, check the SVO2 (levels are low, 20 mmHg, due to high O2 extraction ratio, 55-65%); fluoroscopy can also be used to confirm location.
- Withdraw PAC tip and try to advance again; reposition the patient right side up when crossing the tricuspid valve.
What should we do if complete heart block is persistent?
- Remove the PAC.
- Emergency transvenous pacing.
Why is West zone three the preferred placement of a PAC?
- Pa>Pc>PA
- There is a continuous column of blood flow to this region of the lungs
- there is less of an effect of respirations on arterial weight form in this zone compared to one and two.
How to confirm west zone three placement of PAC:
- chest x-ray: below level of left atrium
- PCWP < PADP by 1-5 mmHg
- PCWP alters PEEP < 50% on increase in PEEP
- PCWP increases by <50% of changes in alveolar pressure
- O2 saturation in wedged position is greater than un wedged position (pulling back of oxygenated blood)
Left lateral decubitus position increases blood flow to west zone ____
2
Left lateral to cubitus position increases ____ pressure
Intra-thoracic
PCWP = PAOP = PAWP
Pulmonary capillary wedge pressure = pulmonary artery occlusion pressure = pulmonary artery wedge pressure
Calculated information from a PAC includes:
- CO
- CI
- SV
- SVR
- PVR
Directly measured information from a PAC:
- CVP
- PAP
- PCWP = PAOP = PAWP
Inferred information gathered from a PCWP (via PAC):
- LAP
- LVEDP & LVEDV
Other capabilities of a PAC (gathered info):
- Blood temp
- PvO2
- SvO2
- AV Venous Pacing
SvO2 normal value
60-75%
Cardiac output, normal value
4-8 L/min
Cardiac index normal value:
2.5 - 4 L/min/m^2
Stroke volume normal range
50-100 mL
Stroke index normal value
25-45 mL/m^2
SVR normal value
900 - 1300 dyn/sec cm^-5
PVR normal value
100 - 300 dyn/sec cm^-5
Name of the method used to calculate, cardiac output
Thermodilution
Cardiac index formula
CI = CO/BSA
Stroke volume formula
SV = CO/HR
Stroke volume index formula
SVI= CI/HR
SVR formula
SVR = 80(MAP-RAP)/CO
Systemic, vascular resistance index formula
SVRI = 80(MAP-RAP)/CI
Pulmonary vascular resistance, formula
PVR = 80(PAP-PCWP)/CO
Pulmonary vascular resistance index formula
PVRI = 80(PAP-PCWP)/CO
Normal systolic pulmonary arterial pressure
20-30 mmHg
Normal mean pulmonary arterial pressure
10-20 mmHg
Normal diastolic pulmonary arterial pressure
5-15 mmHg
Mild systolic pulmonary hypertension
Systolic 35-40 mmHg
Mild mean pulmonary hypertension
> 25 mmHg
Moderate systolic pulmonary hypertension
50-70 mmHg
Severe systolic pulmonary hypertension
> 70 mmHg
Pulmonary hypertension may indicate:
- Left heart disease
- Atrial or ventricular failure
- Valvular disease (e.g., Mitral stenosis, regurgitation)
- Lung disease (COPD, sleep apnea, interstitial lung disease, scleroderma)
- Congenital heart disease with intracardiac shunts
- acute pulmonary embolism
PCWP ~ LAP ~ LVEDP ~ LVEDV
PEEP, Mitral Stenosis, and Mitral Regurgitation will cause the PCWP to ____ the preload of the left side of heart.
Overestimate
Aortic and Pulmonic, and diastolic dysfunction, will ____ LVEDP (LV preload).
Underestimate
Typical left atrial pressure (a-waves) value when measured by PCWP:
4.0-16 mmHg
Typical mean pressure when measured by PCWP:
2.0-12 mmHg
A wave on a PCWP waveform represents:
- Left atrial contraction
- represents an increased left atrial pressure during left atrial contraction
- Usually correlates with the PR interval on the ECG
The C-wave on the PCWP waveform represents:
- closure of the mitral valve
- Not always apparent
The V wave on the PCWP waveform represents:
- ## Left atrial chamber filling
Causes of cannon A waves on a PAC:
- AV dissociation
- Mitral stenosis
atria is trying to pump against closed, mitral valve, resulting in high-pressure
Large V waves indicate:
- Mitral regurgitation
- Myocardial ischemia
- left ventricular diastolic noncompliance 
Describe the process of thermal dilution in order to derive cardiac output
- A cold solution is injected through the proximal port
- The thermometer then measures the temperature change that occurs downstream
- measures the temperature in the pulmonary artery as that cold fluid travels through the heart and gets re-warmed (thermodilution)
- A waveform is created
- The area under the curve correlates to cardiac output
Various types of PAC include:
- Continuous cardiac output measurement.
- Mixed Venus oxygen saturation measurement. (SvO2)
- Cardiac pacing.
- Right ventricular ejection fraction measurement
Which PAC measurement represents the final balance between oxygen supply and demand?
PvO2
When collecting a sample of PvO2, which port is it taken from?
- Distal Port
contains mixed venous drainage from SVC, IVC and heart
Mixed Venus oxygen tension normal value
40 mmHg
What is SvO2 a measurement of?
- Oxygenation saturation from mixed Venus blood in the pulmonary artery
- uses a probe like pulse Ox (not a blood sample)
Which monitoring metric measures the end result of oxygen consumption and delivery?
SvO2
Normal SvO2 value
65-75%
SvO2 varies directly with ____, ____, and ____.
SaO2, Hg, CO
SvO2 varies inversely with ____.
VO2
(Oxygen consumption)
T/F: both CVP & PAC kits can be used for RV pacing.
True
When using a PAC on cardio pulmonary bypass, always:
Withdrawal 3 to 5 cm when going on bypass
What is a common issue when using a pulmonary arterial catheter on cardio pulmonary bypass?
- distal catheter migration may occur due to:
1. Reduction in size of right ventricle.
2. Extra catheter length in the right ventricle.
3. Surgical handling of the heart.
4. Lung deflation.
If PAC becomes dislodged during cardiopulmonary bypass, what should be done
Remove the PAC, do not attempt to refloat it
Why aren’t PACs used more often?
- Expensive.
- In increased risk.
- Difficult to interpret to make clinical judgments.
- Should be used as one of many tools to help guide the care of critically ill patients.
- There is no evidence from large controlled studies to date that preoperative PA catheterization improves outcome regarding hemodynamic optimization; in fact, some studies have suggested that patients actually do worse.
- More non-invasive technology is becoming common.
Swan Ganz catheter picture
Pulmonary Artery Catheter Picture
Catheter Distance & Pressure Picture
Average Adult Distances for PAC placement Picture
Normal Cardiac Metric Values
Pulmonary & Cardiac Formulas
Consequences of Abnormal PCWP Picture
PCWP OVERestimates LVEDP Table Picture
PCWP UNDERestimates LVEDP Table Picture
PCWP waveform picture
C
Respiratory Influences of PAP & PCWP Picture
Cannon A Waves PAC Picture
Large V Waves PAC Picture
Overinflated balloon picture
overwedged catheter picture
Hemodynamic scenarios picture
Hemodynamic Scenarios 2 Picture
