Download RTC PA CATHETER

Swan Gantz Catherter
and the Meaning of its
Readings
Justin Chandler
Surgical Critical Care Fellow
The Pulmonary Artery Catheter and
Its History
The Pulmonary Artery Catheter and
Its History

Cardiac catheterization dates back to Claude
Bernard


used it on animal models
Clinical application begins with Werner
Forssmann in the 1930s

inserted a catheter into his own forearm, guided it
fluoroscopically into his right atrium, and took an Xray picture of it
The Pulmonary Artery Catheter and
Its History

The pulmonary artery catheter
introducted in 1972



Frequently referred to as a SwanGanz catheter, in honor of its
inventors Jeremy Swan and
William Ganz, from Cedars-Sinai
Medical Center
The “sail” or balloon tip was a
modification of the simple portex
tubing method developed by
Ronald Bradley
Ganz added the thermistor
Indications

Diagnostic indications:

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Shock states
Differentiation of high vs low
pressure pulmonary edema
Primary pulmonary
hypertension
Valvular disease
Intracardiac shunts
Cardiac tamponade
Pulmonary embolus
Monitoring and management
of complicated acute
myocardial infarction




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Assessing hemodynamic
response to therapies
Management of multiorgan
failure
Severe burns
Hemodynamic instability after
cardiac surgery
Assessment of response to
treatment in patients with
primary pulmonary
hypertension
Therapeutic indications:

Aspiration of air emboli
Placement

Place an introducer



Hand ports off to RN, inspect and have RN flush
catheter

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R IJ > L SC > R SC > L IJ
Femoral is an option
if CCO, leave tip in the holder to calibrate
Place swandom on catheter
Insert about 15cm and the inflate balloon
Slowly and steadily advance catheter watching the
waveforms
NB When wedged, not the volume required
Placement
Typical Cather Insertion Landmarks
Anatomic Structure
Distance
Right atrium
20 to 25 cm
Right ventricle
30 to 35 cm
Pulmonary artery
40 to 45 cm
Pulmonary capillary wedge
45 to 55 cm
Conformation
Zones of West
Insertion tips



Turn CVP off!
Once in the RV  advance to PA quickly to
avoid coiling, ventricular arrhythmia.
Difficulty getting into PA
Valsava
 Calciun iv
 HOB up

Basics to Remember

Hemodynamic variables should not be
interpreted in isolation
Integration of variables with the clinical situation
increases the accuracy of assessment
 Trends are generally more useful than isolated
variables at a single point in time

What does a PAC tell us?

Direct measurements




CVP
PA (systolic and
diasotolic)
PAOP (wedge)
SvO2 (mixed)

Calculated data


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
Stroke volume (SV/SVI)
Cardiac output (CO/CI)
Vascular resistance (SVR,PVR)
Oxygen delivery
Extended calculations



CCO
Stroke work
End diastolic volume, EF
Variables of Hemodynamics
Variable
Assessment
Stroke volume/index
Pump performance
Cardiac output/index
Blood flow
CVP/RAP
R heart filling pressure
PAOP/Wedge
L heart filling pressure
SvO2
Tissue oxygenation
Normal Values
Variable
Value
Stroke volume (SVI)
50-100 mL/beat (25-45)
Cardiac output (CI)
4-8 L/min(2.5-4.0)
CVP/RAP
2-6 mmHg
PAOP/Wedge
8-12 mmHg
SvO2
0.60 – 0.75
Additional Values
Variable
Value
SVR (SVRI)
900-1300 (1900-2400)dynes
sec/cm5
PVR
40-150 dynes sec/cm5
MAP
70-110 mmHg
Equations to Remember

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CO = SV x HR or SV = CO / HR
SV = EDV – ESV or EDV x EF
C = ΔV/ΔP
SVR = (MAP – CVP) x 80 / CO
LSW = (MAP – LVEDP) x SV x 0.0136
To convert to index: divide by BSA
BSA = [Ht + Wt-60]/100 (in cm & kg)
Cardiac Output



Major determinate of oxygenation delivery to
tissue
Abnormalities are viewed in the context of
SV/SI and SvO2
Remember: a normal CO/CI may be associated
with a low SV/SI in the presence of tachycardia
Factors Affecting CO

Physiologic
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Dysrhythmias
Septal defects
Tricuspid regurg
Respirations

Technical
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Bolusing technique
Themistor malfunction
Factors not affecting
CO:

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Iced vs room temp
NSS vs D5
Pt elevation (<45o)
5 cc vs 10 cc
CO Measurement

Typically done with thermodilution method
A cold solution of fixed volume is injected and a
thermsitor measures the change in temperature
 The area under the curve is integrated to calculate
the CO
 The waveform should be examined to determine if
the technique was good


If the accuracy is in doubt, the Fick method may
be used
CO Waveforms
Fick Method

CO = VO2 / [CaO2 – CvO2] * 10

SaO2 and SvO2 often substituted


CO = VO2 / [SaO2 – SvO2] * Hgb * 1.34* 10
VO2 is not usually measured
Can use 3.5 mL/kg or 125 mL/m2
 If metabolic rate is abnormal, the calculation may be
incorrect

Stroke volume

If low
Inadequate volume (hypovolemia)
 Impaired ventricular contraction
(ischemia/infarction)
 Increased SVR (drugs)
 Valve dysfunction (MVR)


If high

Low vascular resistance (sepsis, drugs)
CVP

Reflects R heart diastolic function and volume
status


60-70% of blood volume is in venous system
Abnormalities are viewed in the context of
SV/SI
If high (>6) implies right ventricular dysfunction,
especially if SV is low
 If low (< 2) implies hypovolemia especially if SV is
low
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CVP
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High
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Hypervolemia
RV failure
Tricupid stenois/regurg
Cardiac tamponade
Cardiac pericarditis
Pulm HTN
Chronic LV failure

Low

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Hypovolemia
Venodiliation
PAOP

Reflects left ventricular end
diastolic volume

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Assumes a static column
of blood from ventricle to
catheter during diastole and
consistent compliance
Abnormalities are viewed in
the context of SV/SI


If high (>18) implies left
ventricular dysfunction,
especially if SV is low
If low (< 8) implies
hypovolemia especially if SV is
low
PAOP
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High
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Hypervolemia
LV failure
Cardiac tamponade
Cardiac pericarditis
Mitral stenosis/regurg
Atrial myxoma
Pulmonary diseases
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Low

Hypovolemia

Aortic regurg
Elevated LVEDP
(>25mmHg) with
decreased compliance

PAOP

Conditions in Which PAD Does Not Equal
PAOP (1 – 4 mm Hg)
Increased PVR
 Pulmonary hypertension
 Cor pulmonale
 Pulmonary embolus
 Eisenmenger’s syndrome

Filling Pressures

If low, but other parameters are normal may
only require observation
If CO/CI are also low, treatment may be warranted
 If SvO2 and/or SV/SI are also low treatment is
needed
 Pulmonary congestion also warrants treatment

SvO2


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Reflects the balance between oxygen delivery
and utilization
The larger the abnormality, the greater the risk
of hypoxemia
Remember: a normal or high SvO2 may
represent a threat to tissue oxygenation
SvO2

A low SvO2 usually warrants investigation

Evaluate:

SV/SI

May require treatment, even if CVP/PAOP are normal
Hb/Hct
 SaO2 (>90%)
 Reasons for oxygen consumption to be elevated

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Abnormally high SvO2 may be indicative of a
septal defect
Continuous Cardiac Output

Newer generation catheter
Uses continuous cardiac output measurements
without need for bolusing
 Allows for right heart “volumetric” data

RVEDV, RVEF, and RVSV
 RVSW and RVSWI

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Also provides continuous SvO2 measurements
Additional Reference Numbers
(R)EDV (SV/EF)
100-160 ml
(R)EDVI
60-100 ml/m2
ESV (EDV-SV)
50-100 ml
ESVI
30-60 ml/m2 (*)
LVSWI
45-75 gm-m/m2/beat
RVSWI
5-10 gm-m/m2/beat
Waveform Analysis

Changes in pressure waveforms are due to:
Blood entering or leaving a chamber
 Changes in wall tension (contraction/relaxation)


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Are always preceded by electrical stimulation
Waveforms are also affected by changes in
intrathoracic pressure (present as rhythmic
changes)
The Waves
The Waves - CVP/RA
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The a wave occurs with atrial contraction

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The c wave occurs with closure of the tricuspid valve

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It occurs at the end of the QRS (RST junction)
The v wave occurs with filling of the atria with the tricupid valve closed

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It occurs after the P wave in the PR-interval
Occurs after the T wave
The mean of the a wave is the CVP
The Waves - RV
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Has a sharp, rapid upstroke and a rapid down stroke
Falls to near zero
The Waves - PA
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Characteristics
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Rapid up stroke and
down stroke
Dicrotic notch (closure of
pulmonic valve)
Smooth runoff
End systolic wave occurs
after the T wave
End diastolic occurs
after the QRS
The Waves - PAOP
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Characteristics
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May contain 3 waves

a atrial contraction
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c closure of mitral valve
(often absent)
v filling of atria with mitral
valve closed
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Found after the QRS
Found well after the T
Mean PAOP

Average the a wave
a Wave Differential
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Large
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Tricuspid or mitral regurg
Decreased ventricular
compliance
Loss of A-V synchrony
Junctional rhythms
Tachycardia (>130)
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Absent
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A-fib
Junctional rhythms
Paced rhythms
Ventricular rhythms
v Wave Differential
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Large
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Tricuspid or mitral regurg
Noncompliant atrium
Ventricular
ischemia/failure
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Absent
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V-fib
Asystole
PEA
Diagnosis by Waveform

Mitral insuffiency
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Prominent v wave
Proximity of v and a
waves
Returns to a more normal
configuration after
afterload reduction
Diagnosis by Waveform
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VSD
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Presents with increased
SvO2
Note the delay in the v
wave
May respond to afterload
reducers
Diagnosis by Waveform

Cardiac Tamponade


As with constrictive
pericarditis, there is
equalization of diastolic
pressures
Note the loss of the y
descent in cardiac
tamponade
Diagnosis by Waveform
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Constrictive pericarditis


Note the equalization of
the diastolic pressures
Unlike tamponade, there
is an exaggeration of the y
descent due to a more
rigid pericardium
Points to remember

Intrathoracic pressure during inhalation and
exhalation cause pressures in the heart to vary

Therefore all pressures should be measured at endexpiration when intrathoracic pressure is closest to
zero
Points to Remember

Limitations in hemodynamic monitoring

Ventricular filling pressures do not always accurately reflect ventricular
filling volume

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The PAOP is normally slightly (1-5 mm Hg) less than the PAD pressure

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The pressure-volume relationship depends upon ventricular compliance
If compliance changes, the pressure-volume relationship changes
This relationship stills exists with pulm hypertension due to LV failure
However, with an ↑ PVR or tachycardia (>125 bpm) this relationship may
breakdown and the PAD becomes significantly higher than the PAOP
The PAOP may not equal LVEDP when
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there is high alveolar pressures
when the catheter tip is above the left atrium
severe hypovolemia
tachycardia (130 bpm)
in mitral stenosis.
Points to remember

Calculated variables (e.g. SVR, PVR & SV/SI)
are limited in value due to assumptions made in
their calculations
Complications

Air embolism
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Arrhythmias

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S&S: hypoxemia, cyanosis, hypotension/syncope, “machinery
murmur”, elevated CVP, arrest
Tx: place in left lateral trendelenburg, FiO2 of 100%, attempt
aspiration of air, CPR
Prevention: keep balloon inflated, minimize insertion time
Tx: removal of catheter, ACLS
Heart blocks


Typically RBBB occurs, so avoid PACs in LBBB
Tx: transvenous/transcutaneous pacers, PACs with pacer
Complications

Knotting

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Prevention: minimize insertion time, avoid pushing agaist
resistance, verify RA to RV transition
Tx: check CXR, attempt to unknot
Pulmonary artery rupture

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S&S: hypoxemia, hemoptysis, circ collapse
Prevention: withdraw PAC if spontaneously wedges or
wedges with < 1.25 cc of air
Tx: stop anti-coagulation, affected side down, selective
bronchial intubation, PEEP, surgical repair (CPB or ECMO)
Complications

Pulmonary infarction
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Prevention

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Avoid distal positioning of catheter
Check CXR
Monitor PA EDP instead of PAOP
Pull back if spontaneous wedge occurs
Limit air in cuff (pull back if < 1.25 cc)
Tx



CXR
Check cath position, deflate and withdraw
Observe
Complications

Infection

Prevention!
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Aseptic technique
Dead-end caps
Sterile sleeve (swandom)
Minimize entry into system
Avoid glucose containing fluid
Avoid over changing of tubing, etc (72-96 hr)
Remove catheter ASAP
Thrombus

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Prevention – continuous flush +/- heparin
Tx – lytic agent ; remove catheter
Emerging Technology

Devices exist that use arterial pressure waveform to
continuously measure cardiac output


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Variations of the arterial pressure are proportional to stroke
volume
Several studies demonstrate that SVV has a high sensitivity
and specificity in determining if a patient will respond
(increasing SV) when given volume (“preload
responsiveness”)
Limitations


Only used in mechanically ventilated pts
Wildly inaccurate when arrhythmias are present
Emerging Technology

Impedance Cardiography (ICG)

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Converts changes in thoracic
impedance to changes in volume
over time
ICG offers noninvasive, continuous,
beat-by-beat measurements of:

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Stroke Volume/Index (SV/SVI)
Cardiac Output/Index (CO/CI)
Systemic Vascular Resistance/Index
(SVR/SVRI)
Velocity Index (VI)
Thoracic Fluid Content (TFC)
Systolic Time Ratio (STR)
Left Ventricular Ejection Time (LVET)
Pre-Ejection Period (PEP)
Left Cardiac Work/Index
(LCW/LCWI)
Heart Rate
In a Nutshell

Right heart failure


Hypotension

Left heart failure


Low CI, high PVR

High PAOP, low CI, high
SVR



High PAOP, low CI,
CVP ≈ POAP


Low CVP, PAOP, CI
High SVR
Cardiogenic

Tamponade

Hypovolemia
High CVP,PAOP, SVR
Low CI
Sepsis


Low CVP, PAOP, SVR
High CI
References

Pulmonary Artery Catheter Education Project
 http://www.pacep.org

Chatterjee, The Swan-Ganz Catheters: Past, Present, and Future: A Viewpoint.
Circulation 2009;119;147-152

Edwards Scientific
 http://ht.edwards.com/presentationvideos/powerpoint/strokevolumevariation/s
trokevolumevariation.pdf
Question #1

Which one of the following statements is
most correct?
A) A CVP <2 mmHg usually reflects
hypovolemia if the SVI is>45 mL/beat/M2
B) A CVP >6 mmHg usually reflects RV failure
if the SVI is <25 mL/beat/M2
C) A PAOP >18 mmHg usually reflects LV
failure if the SVI is >45 mL/beat/M2
D) A PAOP <8 mmHg usually reflects
hypovolemia if the SVI is >25 mL/beat/M2
Answer #1

Which one of the following statements is
most correct?
A) A CVP <2 mmHg usually reflects
hypovolemia if the SVI is>45 mL/beat/M2
B) A CVP >6 mmHg usually reflects RV failure
if the SVI is <25 mL/beat/M2
C) A PAOP >18 mmHg usually reflects LV
failure if the SVI is >45 mL/beat/M2
D) A PAOP <8 mmHg usually reflects
hypovolemia if the SVI is >25 mL/beat/M2
Question #2

Identify the condition most consistent with
the following hemodynamic profile:
SvO2 ... 0.50 ... PAOP ... 21 mmHg
CI ... 2.2 L/min/M2 ...CVP/RA ... 4 mmHg
SVI ... 23 ml/beat M2 ... HR ... 98
A) Hypovolemia
B) Hypervolemia
C) LV dysfunction/failure
D) Bilateral ventricular failure
Answer #2

Identify the condition most consistent with
the following hemodynamic profile:
SvO2 ... 0.50 ... PAOP ... 21 mmHg
CI ... 2.2 L/min/M2 ...CVP/RA ... 4 mmHg
SVI ... 23 ml/beat M2 ... HR ... 98
A) Hypovolemia
B) Hypervolemia
C) LV dysfunction/failure
D) Bilateral ventricular failure
Question #3

Identify the condition most consistent with
the following hemodynamic profile: SvO2 ...
0.47 ... PAOP ... 4 mm Hg
CI ... 2.0 L/min/M2 ... CVP/RA ... 2 mm
Hg
SVI ... 19 ml/beat/M2 ... HR ... 111
A) Hypovolemia
B) Hypervolemia
C) LV dysfunction/failure
D) Bilateral ventricular failure
Answer #3

Identify the condition most consistent with
the following hemodynamic profile: SvO2 ...
0.47 ... PAOP ... 4 mm Hg
CI ... 2.0 L/min/M2 ... CVP/RA ... 2 mm
Hg
SVI ... 19 ml/beat/M2 ... HR ... 111
A) Hypovolemia
B) Hypervolemia
C) LV dysfunction/failure
D) Bilateral ventricular failure
Question #4

Which of the combined set of hemodynamic values is of
greatest concern?
A) CO = 6.9 L/min; CI = 3.8 L/min/M2 SV = 63 mL/beat;
SVI = 34 mL/beat/M2 BP = 102/52 mm Hg SvO2 = 0.83

B) CO = 4.3 L/min; CI = 2.5 L/min/M2 SV = 43 mL/beat;
SVI = 25 mL/beat/M2 BP = 94/62 mm Hg SvO2 = 0.64

C) CO = 6.3 L/min; CI = 3.7 L/min/M2 SV = 64 mL/beat;
SVI = 37 mL/beat/M2 BP = 90/56 mm Hg SvO2 = 0.75

D) CO = 3.8 L/min; CI =2.3 L/min/M2 SV = 73 mL/beat; SVI
= 43 mL/beat/M2 BP = 100/58 mm Hg SvO2 = 0.72
Answer #4

Which of the combined set of hemodynamic values is of
greatest concern?
A) CO = 6.9 L/min; CI = 3.8 L/min/M2 SV = 63 mL/beat;
SVI = 34 mL/beat/M2 BP = 102/52 mm Hg SvO2 = 0.83

B) CO = 4.3 L/min; CI = 2.5 L/min/M2 SV = 43 mL/beat;
SVI = 25 mL/beat/M2 BP = 94/62 mm Hg SvO2 = 0.64

C) CO = 6.3 L/min; CI = 3.7 L/min/M2 SV = 64 mL/beat;
SVI = 37 mL/beat/M2 BP = 90/56 mm Hg SvO2 = 0.75

D) CO = 3.8 L/min; CI =2.3 L/min/M2 SV = 73 mL/beat; SVI
= 43 mL/beat/M2 BP = 100/58 mm Hg SvO2 = 0.72
Question #5

Immediate treatment of pulmonary artery
rupture may include all of the following
except:
A) Discontinuation of anticoagulation
B) Placing patient in lateral position with
unaffected side down.
C) Selective bronchial intubation
D) PEEP
Answer #5


Immediate treatment of pulmonary artery
rupture may include all of the following
except:
A) Discontinuation of anticoagulation
B) Placing patient in lateral position with
unaffected side down.
C) Selective bronchial intubation
D) PEEP
E) Hire a lawyer