Pulmonary Artery Catheterizationand Interpretation

Evan T. Lukow

IM – Residency Lecture Series

July 7, 2004

Goal: To gain a basic knowledge of Pulmonary Artery Catheterization in the ICU

• Objectives:• The Resident will:

– Understand the basic structure of the Swan-Ganz Catheter.

– Develop a basic knowledge of how to place a PAC.– Understand when and why to place a Swan-Ganz

catheter.– Determine what hemodynamic parameters a Swan-Ganz

catheter can generate (measured and derived).– Apply these parameters to make appropriate diagnoses of

clinical scenarios.

The Swan-Ganz (Pulmonary Artery) Catheter• 110 cm long, outside diameter of

2.3mm (7 Fr).• The tip of the catheter has a 1.5 cc

capacity balloon, that when inflated covers the distal tip of the catheter.

• Ports:– Balloon Inflation – 1.5 cc syringe.– Distal port (at the tip) – to measure

CVP.– Thermistor port (4 cm from distal

port) – to measure CO.– Proximal port (30 cm form distal

port) – to measure PAP and PAWP.

• Additional Features: Temporary pacer leads, fiberoptics for svO2, rapid response thermistor for RVEF, and continous thermodilution CO sensor.

PAC Insertion

• Insertion of a PA catheter is usually via the subclavian (left) or internal jugular (right), but may sometimes be placed in the femoral vein if needed (preference given to the most direct access to the right atrium).

• Once into the RA, the balloon is inflated at the tip to allow for the catheter to follow the flow of blood from the RA, through the tricuspid valve, into the RV, through the pulmonic valve and into the pulmonary artery.

• When properly positioned the catheter’s distal tip lies in the pulmonary artery and the proximal port lies in the RA, thus allowing for the measure of RAP and PAWP, simultaneously.

PAC Insertion

• The catheter's position can be monitored indirectly by the pressure tracing on the monitor and its relationship to specific areas of the heart and vasculature.

• Once in the pulmonary artery and in the wedged position, the classic PAWP waveform will be seen, and all of the hemodynamic parameters can be obtained yielding a profile for interpretation and eventual treatment of a patients particular condition.

Why place a Swan-Ganz?

• Cardiac Intensive Care:– Cardiogenic Shock (LV/RV

infarct, Acute MR)

– Cardiac tamponade

– Constrictive pericarditis

– Guiding inotropic therapies

• Non-Cardiac Intensive Care:– Determining “fluid status”

– Guiding fluid resuscitation

– Characterizing shock states• Hypovolemic (hemorrhage,

dehydration)

• Distributive (sepsis, SIRS, anaphylaxis)

• Cardiogenic (failure, infarct)

• Obstructive (PE, tamponade, PTX)

Note: Always used for diagnosis and evaluation of treatment.

Consequences

• Cautions/Contraindications:– Coagulopathy – use

compressible site such as R internal jugular or femoral

– LBBB – may progress to complete heart block

– Aberrant anatomy – recommend radiographic guidance

– “If you think of it use it”

• Complications:– Vascular:

• Arterial rupture

• PTX

• Nerve injury (Horner’s, brachial plexus, phrenic)

• Air embolism

• Hemorrhage/Infection

– Catheter:• Arrhymias/Heart Block

• Thrombosis/Embolism

• Sepsis/Endocarditis

• PA rupture (0.2%)

• Pulmonary infarction (1.4%) - overwedging

Hemodynamic Parameters Measured By Swan-Ganz

• Central Venous Pressure (CVP)– CVP = RAP = RVEDP

• Pulmonary Artery Pressure (PAP)

• Pulmonary Artery Wedge Pressure (PAWP)– PAWP = LAP = LVEDP

• Cardiac Output (CO)– Via thermoditulion

• Intra-arterial blood pressure (Art. Line)

• Mixed venous Saturation (SVO2)

Hemodynamic Parameters Derived by Swan-Ganz

• Cardiac Index

• Systemic Vascular Resistance (SVR)

• Pulmonary Vascular Resistance (PVR)

• Systemic Oxygen Transport Data (see next slide)

• CI = CO/BSA

• SVR = CI/HR

• PVR = (PAP – PAWP) x 80/CI

Other parameters such as RVEDV, RVEF, R and L SWI, can be determined depending on the type of catheter used and monitors

available.

Systemic Oxygen Transport DataDerived by Swan-Ganz

• Mixed Venous Oxygen Saturation (SvO2): 65-75%

– A measure of the oxygen sat. in blood obtained form the pulmonary arterial circulation and is used to determine the amount of oxygen used in the peripheral microcirculation.

• Oxygen Delivery (DO2): 520-570 mL/min.m2

– A measure of the rate of oxygen transport in the blood, a product of CO and arterial oxygen concentration.

• Oxygen Uptake (VO2): 110-160 ml/min.m2

– The rate of oxygen uptake in the systemic microcirculation, the product of CO and difference oxygen content in arterial and mixed venous blood.

• Oxygen Extraction Ratio (O2ER): 20-30%

– The fractional uptake of oxygen from the systemic microcirculation, equivalent to the ratio between Oxygen delivery and uptake.

Hemodynamic Profilesin Heart Failure

• Right Heart Failure– High RAP

– Low CI

– High PVR

– Normal VO2

• Left Heart Failure– High PAWP

– Low CI

– High SVR

– Normal VO2

Note: Heart Failure has appropriate oxygen uptake

(VO2) as opposed to clinical shock states.

Hemodynamic Profilesin Shock

Hypovolemic Cardiogenic Distributive(vasogenic)

Obstructive

Hemorrhage,

Dehydration

Heart Failure,

Infarct

Sepsis, SIRS,

Anaphylaxis,

Adrenal dys.

PE, PTX,

Cardiac Tamponade

Low CVP

Low PAWP

Low CO

High SVR

High CVP

High PAWP

Low CO

High SVR

High CO

Low SVR

Low PAWP

CT – RAP = PAWP = RVEDP

PE – High RAP, High PAP

ALL shock states are characterized by inadequate tissue oxygenation and a low

oxygen uptake (VO2)

Practical Cases

Case 1:

• 75 yo female with lung CA, s/p R pneumonectomy has acute desaturation and requires reintubation. Temp 100.4, resp. 36, BP 120/75, HR 120. Rales on L, no BS on R, cardiac normal. CXR – diffuse infiltrates on L.

• PAC Data: The most likely diagnosis is:

– RAP 10 (2-6) A. PE

– PAP 45/28 (25/12) B. AMI

– PAWP 10 (8-12) C. ARDS

– CI 3.8 (2.5-4) D. Fluid Overload

– SVR 1700 (2000)

Case 1:

• PAC Data: The most likely diagnosis is:

– RAP 10 (2-6) A. PE

– PAP 45/28 (25/12) B. AMI

– PAWP 10 (8-12) C. ARDS

– CI 3.8 (2.5-4) D. Fluid Overload

– SVR 1700 (2000)

• This patient has increased right sided pressures and normal left sided pressures, and with correlation to clinical presentation, suggests acute lung pathology (ARDS) as the cause of her respiratory distress.

Case 2:

• 57 yo smoker is admitted to hospital with CP, N + V, JVD is noted, extremities are cool to touch, T - 98.6, BP - 80/60, HR – 112, R - 24, lungs are clear, heart – RRR without murmur, ECG – ST elevation in inferior leads.

• PAC Data: The most likely diagnosis is:

– RAP 15 (2-6) A. Inf. MI with PE

– PAP 30/10 (25/12) B. Inf. MI with RV infarct

– PAWP 8 (8-12) C. Inf. MI with ^ fluid vol.

– CI 2.1 (2.5-4) D. Inf. MI with LV Failure

– SVR 2200 (2000) E. Inf. MI with MR

Case 2:

• PAC Data: The most likely diagnosis is:

– RAP 15 (2-6) A. Inf. MI with PE

– PAP 30/10 (25/12) B. Inf. MI with RV infarct

– PAWP 8 (8-12) C. Inf. MI with ^ fluid vol.

– CI 2.1 (2.5-4) D. Inf. MI with LV Failure

– SVR 2200 (2000) E. Inf. MI with MR

• This pt. has ECG changes consistent with an acute Inferior wall MI, and PAC pressures (decreased CI, and RAP > PAWP) consistent with RV failure, which occurs in 25% of Inferior wall MI’s.

Case 3:

• 67 yo with COPD intubated for respiratory failure and sepsis, after CVP, pt. became hypoxic, acidotic, tachycardic, BP fell from 130/80 to 70/45.

• PAC Data: The most likely diagnosis is:

– RAP 26 (2-6) A. Cardiac Tamponade

– PAP 55/28 (25/12) B. Tension PTX

– PAWP 24 (8-12) C. Air embolism

– CI 1.8 (2.5-4) D. LV failure

– SVR 3000 (2000) E. Myocardial wall rupture

– SvO2 55% (65-75%)

Case 3:

• PAC Data: The most likely diagnosis is:

– RAP 26 (2-6) A. Cardiac Tamponade

– PAP 55/28 (25/12) B. Tension PTX

– PAWP 24 (8-12) C. Air embolism

– CI 1.8 (2.5-4) D. LV failure

– SVR 3000 (2000) E. Myocardial wall rupture

– SvO2 55% (65-75%)

• Along with clinical evidence of a PTX, this patients PAC pressure correlate with a tension PTX due to a global increase in both Right and Left sided heart pressures, a generalized hypoxemia, and decreased CO.

Case 4:

• 55 yo with COPD who was ventilated becomes anxious 15 minutes after weaning, T-98.6, BP – 160/100, HR – 130, R – 36, Sat – 87% at FiO2 40%, Chest- diffuse wheezing, Heart – without murmur, ABG – 7.36, 30, 51.

• PAC Data: The most likely diagnosis is:

– RAP 14 (2-6) A. Anxiety

– PAP 45/27 (25/12) B. Bronchospasm

– PAWP 23 (8-12) C. LV dysfunction

D. RV dysfunction

Case 4:

• 55 yo with COPD who was ventilated becomes anxious 15 minutes after weaning, T-98.6, BP – 160/100, HR – 130, R – 36, Sat – 87% at FiO2 40%, Chest- diffuse wheezing, Heart – without murmur, ABG – 7.36, 30, 51.

• PAC Data: The most likely diagnosis is:– RAP 14 (2-6) A. Anxiety – PAP 45/27 (25/12) B. Bronchospasm– PAWP 23 (8-12) C. LV dysfunction

D. RV dysfunction

• The increased left sided pressures in this patient suggests left sided failure, patient was reintubated and PAC values corrected somewhat, with some residual LVF evidence.

Case 5:

• 55 yo with CAD and RA with a total hip has CP, SOB, and hypotension on POD #3, T-100.3, BP – 90/60, HR – 125, R – 32, Chest- bilateral wheezing, Heart – without murmur, CXR – infiltrates and atelectasis on R base, ECG – diffuse ST/T changes.

• PAC Data: The most likely diagnosis is:

– RAP 22 (2-6) A. PE

– PAP 55/32 (25/12) B. ARDS

– PAWP 10 (8-12) C. MI

– CI 2.2 (2.5-4) D. Right-sided endocarditis

– SVR 2600 (2000)

Case 5:

• PAC Data: The most likely diagnosis is:

– RAP 22 (2-6) A. PE

– PAP 55/32 (25/12) B. ARDS

– PAWP 10 (8-12) C. MI

– CI 2.2 (2.5-4) D. Right-sided endocarditis

– SVR 2600 (2000)

• This patient has clinical evidence of a PE, elevated right-sided pressures, normal left-sided pressures (PAP>PAWP) and a reduced CO all indicative of PE.

Case 6:

• 41 yo with sinusitis, spontaneous PTX, 3-day admission, 9 day course of antibiotics, develops CP, worse with sitting, T-101.3, BP – 110/85, HR – 120, R – 32, Sat – 88%, Lungs – clear, Heart – without murmur, ECG – low-voltage, CXR – WNL.

• PAC Data: The most likely diagnosis is:– RAP 22 (2-6) A. Tension PTX– PAP 40/22 (25/12) B. Cardiac tamponade– PAWP 22 (8-12) C. LV failure– CI 2.1 (2.5-4) D. PE– SVR 3000 (2000)

Case 6:

• PAC Data: The most likely diagnosis is:– RAP 22 (2-6) A. Tension PTX– PAP 40/22 (25/12) B. Cardiac tamponade– PAWP 22 (8-12) C. LV failure– CI 2.1 (2.5-4) D. PE– SVR 3000 (2000)

• This patient most likely has cardiac tamponade due to an increase in right-sided filling pressure, decreased CO, along with clinical evidence of pericardial inflammation. Along with PAC data, an echo would be indicated to evaluate the size of the pericardial effusion for possible drainage.

References

• ICU Book Second Edition, Paul L. Marino – Chapter 10 (1998)

• Critical Care Procedures, XXXXX – Chapter 3 (1995)

• PACs in the ICU, Jonathan D. Truwit – Journal of Critical Illness, Feb, 2003.

• Principles of Critical Care, J. Hall (1992)