Mod1: Monitoring for Cardiac Surgery - Pulmonary artery catheter Flashcards
Pulmonary artery catheter
When was the PA catheter introduced?
Invented in 1970 by Swan, Ganz and colleagues for hemodynamic assessment of patients with acute myocardial infarction
Became routine monitoring for the ICU
Pulmonary artery catheter
Recently, why are providers begining to shy away from using the PA catheter?
They are begining to see that the risks of PAC outweight its benefits
Not only are survival rates the same between those who have it and those who don’t, but studies have also shown that PA catheter-groups suffer more pulmonary complications
Influence on patient outcomes has become controversial as clinical studies fail to show positive outcomes
PULMONARY ARTERY CATHETER
What are the physical characteristics of the PA catheter?
(#lumens, lenght)
5 lumen catheter
110 cm long

PULMONARY ARTERY CATHETER
Which port is used for pulmonary artery pressure monitoring and measuring mixed venous gas?
Distal port

PULMONARY ARTERY CATHETER
Which port is used for CVP monitoring, CO injections
A port located 30 cm from tip (CVP port)

PULMONARY ARTERY CATHETER
Which port is used for RV pacing/Infusion output
Port located 20 cm from tip (RV port)

PULMONARY ARTERY CATHETER
Which port houses wiring to connect the thermistor near the catheter tip to monitor thermodilution for CO once the blood circulates and reaches the pulmonary artery?
Thermistor port

PULMONARY ARTERY CATHETER
Which port is used to inflate the ballon at the tip of the catheter?
Air channel

PULMONARY ARTERY CATHETER - INDICATIONS
What is a major benefit of the PA catheter in assessing cardiac function that is not possible just with clinical s&s?
Provides Quantitative assessment cardiac function that cannot be otherwise be accurately predicted from standard clinical signs and symptoms
Evaluate & guide treatment of hemodynamic alterations
PULMONARY ARTERY CATHETER - INDICATIONS
For which conditions is the use of the PA catheter indicated?
CABG
Recent MI or Unstable Angina
Valvular disease
Presence pulmonary HTN
Combined coronary stenosis & valvular disease
PULMONARY ARTERY CATHETER - INDICATIONS
For which conditions is the PA catheter not usually indicated for?
EF > 50%
Good ventricular wall motion present
Monitoring CVP sufficient
PULMONARY ARTERY CATHETER - INDICATIONS
T/F: For a pt to undergo cardiac surgery, you mus consult with the surgeon before making the decision to forego a PA catheter
True
PULMONARY ARTERY CATHETERIZATION
Why does the insertion of a PA catheter require a large-bore introducer (usually a 9Fr)?
To facilitate PAC insertion
PULMONARY ARTERY CATHETERIZATION
Why does PA catherization require a catheter that has a hemostasis valve?
Because the PA catheter is then inserted through the hemostasis valve
PULMONARY ARTERY CATHETERIZATION
What’s the next step after the catheter is inserted throught the hemostasis valve?
Nonsterile connections are made to monitoring devices
The 5 ports are then handed to a non-sterile assistant who connects all five ports and zeroe the transducers in the following sequence:
- Connect the distal port(yellow) to the pulmonary artery pressure transducer (yellow to yellow)*
- Blue port is connected to CVP (blue to blue)*
- 3 cc syringe connected to red balloon port*
- Flush connected to orange port*
- Level the transducer at the level of the pt’s heart*
- Zero the transducer*

PULMONARY ARTERY CATHETERIZATION
T/F: It is recommended that the PA catheter be zeroed prior to floating the Swan
True
PULMONARY ARTERY CATHETERIZATION
When the PA catheter is inserted through the subclavian or internal jugular vein, what position should the pt be in?
Flat or Reverse trendelenburg
PULMONARY ARTERY CATHETERIZATION
Eventhough you want to verify placement according to the waveform on the screen, what other information could you use for confirmation?
The numbers on the screen
PULMONARY ARTERY CATHETERIZATION
Why is continuous pressure monitoring during PAC insertion required?
To determine location of the catheter tip
PULMONARY ARTERY CATHETERIZATION
Why is the PA catheter initially inserted through the hemostasis valve to the 20 cm mark?
Because the 20 cm mark places the tip of the catheter at the RA
PULMONARY ARTERY CATHETERIZATION
What’s the next step once the the 20 cm mark is at the hub of the introducer?
Inflate the balloon when the 20 cm mark is at the hub of the introducer
Advance the catheter in a smooth foward fashion while watching the monitor for changes in the waveform
PULMONARY ARTERY CATHETERIZATION
While advancing the PA catheter, what level corresponds to the Right ventricle?
30-35 cm
PULMONARY ARTERY CATHETERIZATION
While advancing the PA catheter, what level corresponds to the Pulmonary artery?
40-45 cm
PULMONARY ARTERY CATHETERIZATION
The catheter is advanced until what pressure is obtained? At what level is this anticipated to occur?
Advance the PAC until the PCWP is obtained
Usually around 45-55 cm at the hub
PULMONARY ARTERY CATHETERIZATION
T/F: The catheter should always move smoothly and should not be advanced against any resistance
True
PULMONARY ARTERY CATHETERIZATION
While advancing PA catheter, what should be use to guide positioning?
A. Change in waveform
B. Change in values on the monitor
A. Change in waveform
B. Change in values on the monitor

PULMONARY ARTERY CATHETERIZATION
T/F: Catheter depths can be used to verify catheter position
False
Depths are only used as a guide.
Must always follow waveform morphology to verify catheter position

PULMONARY ARTERY CATHETERIZATION
T/F: Catheter site affects catheter depth
True
There are variations in depth depending on catheter site
PULMONARY ARTERY CATHETERIZATION
How much should be added to normal depth when the catheter is inserted in the left IJ?
An additional 5-10 cm
PULMONARY ARTERY CATHETERIZATION
How much should be added to normal depth when the catheter is inserted from femoral vein?
15 cm additional
PULMONARY ARTERY CATHETERIZATION
How much should be added to normal depth when the catheter is inserted from antecubital veins?
30-35 cm
PULMONARY ARTERY CATHETERIZATION
What are the 4 main different pressure tracing displayed by the PA catheter as it is being floated?
RA pressure
RV pressure
PAP
Pulmonary artery occlusive (“wedge”) pressure

PULMONARY ARTERY CATHETERIZATION
What does the waveform looks like at 20 cm?
At 20 cm the waveform resembles the CVP, and
Displays a, c & v waves

PULMONARY ARTERY CATHETERIZATION
What are the normal values of the RA pressure?
0-8 mmHg
CVP: 1-6mmHg* (from slide 72)

PULMONARY ARTERY CATHETERIZATION
What are normal RV pressures?
How do they compare to RA pressures?
15-30/0-8 mmHg
RV pressure show a higher systolic pressure than seen in the RA, but end-diastolic pressures are equal

PULMONARY ARTERY CATHETERIZATION
What are normal PA pressures?
How do they compare to RV pressures?
15-30/11-12 mmHg
PA pressures show a diastolic step up compare to RV pressures

PULMONARY ARTERY CATHETERIZATION
What are normal values for Pulmonary artery occlusive (“wedge”) pressure?
5-12 mmHg
6-12mmHg* (slide 72)
PULMONARY ARTERY CATHETERIZATION
How does Pulmonary artery occlusive (“wedge”) pressure compare to CVP?
PAOP have the same morphology as CVP pressures
But the a, c & v waves appear much later in the cardiac cycle relative to the EKG

PULMONARY ARTERY CATHETERIZATION
On the chest x-ray used to verify PA catheter placement, where should the tip of the catheter be located?
The tip of the catheter should be within 2 cm of the cardiac silhouette on the anterior posterior chest film

HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
Which hemodynamic values can be measured by the PA catheter?
CVP - CO - PAP - PCWP
Mixed venous oxygen saturations ( SVO2)
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
Where is the Central Venous Pressure (CVP) recorded?
From proximal port in the SVC at the junction or RA
CVP = RAP
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
CVP = RVEDP under which condition?
No obstruction exist between atrium & ventricle
For example: No Tricupsid stenosis
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
What technique is used to calculate Cardiac output?
The thermodilution technique
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
When Pulmonary Artery Pressure (PAP) are measured at the tip/distal port, how is the balloon?
Balloon is deflated
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
Which hemodynamic parameter do PA pressures reflect?
RV function
PVR
LA filling pressures
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
When the Pulmonary Capillary Wedge Pressure (PCWP) is measured at the tip/distal port, how is the balloon?
Balloon is inflated
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
Under which condition are PAD = PCWP = LAP = LVEDP?
Indirectly & when no obstruction exists between atrium and ventricle (ie. mitral stenosis/Pulmonary HTN)
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
Why should we look at the numbers from the PA catheter as changes in pressure but not changes in volume?
Changes in compliances of the heart may change pressures whithin the heart, but not necessarily the volumes in the heart
This is how you may have a pt with high wedge pressures and normal cardiac compliance and function, and they are categorized as hypervolemic and not in heart failure
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
What is assessed via Mixed venous oxygen saturations (SVO2) measurement?
Indirect assessment of total body O2 supply and demand
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
What are the Determinants of SvO2?
O2 delivery/supply
O2 extraction/demand
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
What are the normal SvO2 values?
Normal SVO2 is 60-80%
With a normal oxygen tension of 35-40 mmHg
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
Changes in which factors could cause a decreased in SVO2?
↓O2 delivery (anemia/↓CO) or ↑O2 consumption
HEMODYNAMIC PARAMETERS MEASURED BY THE PAC
Where should accurate sampling of SVO2 blood be done?
From the PA port of the PA catheter
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Cardiac Index (CI) = ?
Normal values?
CI = CO/BSA
Normal CI: 2.4 - 4.0L/min/m2
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Stroke Volume Index (SVI) = ?
Normal values?
SVI = CI/HR
Normal SVI: 40 - 70mL/beat/m2
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Systemic Vascular Resistance (SVR) =?
What does Systemic Vascular Resistance (SVR) reflect?
SVR = 80 x (MAP – CVP) /CO
Reflects impendence of the systemic vascular tree
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Normal values for Systemic Vascular Resistance Index (SVRI)?
Normal SVRI: 1600-2400 dynes-sec-m2/cm5
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Pulmonary Vascular Resistance (PVR) = ?
What does PVR reflect?
PVR = 80 x (PAP – PCWP)/CO
Reflects impendence of pulmonary circuit
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Normal values for the Pulmonary Vascular Resistance Index (PVRI)?
Normal PVRI: 200-400 dynes-sec-m2/cm5
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Left Ventricular Stroke Index (LVSI) = ?
LVSI = (MAP – PCWP) x SVI x 0.136
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Normal values for Left Ventricular Stroke Work Index (LVSWI)?
Normal LVSWI: 40-60 g.m/m2
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Right Ventricular Stroke Index (RVSI) = ?
RVSI = (PAP – CVP) X SVI x 0.136
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Normal values for Right Ventricular Stroke Work Index (RVSWI)?
Normal RVSWI: 4-8 g.m/m2
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Normal RV Ejection fraction:
46-50%
DERIVED/CALCULATED PAC HEMODYNAMIC PARAMETERS
Normal RV End-diastolic volume (RVEDV):
80-150 mL/m2
BENEFITS OF THE PULMONARY ARTERY CATHETER
T/F: From a treatment decision standpoint, information gathered from PAC data can beneficially change therapy
True
BENEFITS OF THE PULMONARY ARTERY CATHETER
How could information gathered from a PA catheter prior to surgery be used?
Lead to cancellation or modification of surgical procedure or anesthetic management
Thereby preventing morbidity and mortality
BENEFITS OF THE PULMONARY ARTERY CATHETER
What does the PA catheter allow to monitor perioperatively?
Provides invasive hemodynamic monitoring during surgery
Assess volume status/guide perioperative fluid management
BENEFITS OF THE PULMONARY ARTERY CATHETER
Which changes in PA catheter values are indicative of RV dysfunction?
↑CVP
↓ CVP to mean PA gradient, no change in PCWP
↓CO
BENEFITS OF THE PULMONARY ARTERY CATHETER
Which changes in PA catheter values are indicative of LV dysfunction?
↑ PAP, ↑ CVP, ↑PCWP
↓BP, ↓CO
BENEFITS OF THE PULMONARY ARTERY CATHETER
Which changes in PA catheter values are indicative of pulmonary HTN?
PA diastolic pressure > PCWP
BENEFITS OF THE PULMONARY ARTERY CATHETER
How can the PA catheter be used to assess valvular disease?
By measuring pressure gradients across the valves
BENEFITS OF THE PULMONARY ARTERY CATHETER
Which pressure gradient changes noted on PA catheter may indicate Tricuspid stenosis
CVP-RVEDP gradient
BENEFITS OF THE PULMONARY ARTERY CATHETER
Which pressure gradient changes noted on PA catheter may indicate Pulmonic stenosis?
RV systolic-PA systolic pressure gradient
BENEFITS OF THE PULMONARY ARTERY CATHETER
Mitral valve disease may be assessed from which PA catheter value?
PCWP
BENEFITS OF THE PULMONARY ARTERY CATHETER
Which changes in PA catheter values are indicative of Mitral valve insufficiency?
↑pulmonary venous pressure = abnormal V wave
BENEFITS OF THE PULMONARY ARTERY CATHETER
Which changes in PA catheter values are indicative of Mitral valve Stenosis?
Not routinely done in OR
BENEFITS OF THE PULMONARY ARTERY CATHETER
Although EKG remains cornerstone for diagnosing ischemia, it is not always sensitive. Which type of ischemia could be diagnozed early via PA catheter?
Subendocardial ischemia
BENEFITS OF THE PULMONARY ARTERY CATHETER
How does Subendocardial ischemia presents on PA catheter monitoring?
Associated with ↓ventricular compliance
↑ PA pressures or ↑PCWP
BENEFITS OF THE PULMONARY ARTERY CATHETER
How does ischemia of papillary muscle presents on PA catheter monitoring?
Pathologic V waves may occur
COMPLICATIONS OF THE PULMONARY ARTERY CATHETER
Which complications may occur with PA catheter placement?
Arrhythmias
Complete heart block (Transcutaneous pacing may be needed)
Thromboembolism
Pulmonary infarction (continued wedging)
Cardiac perforation
PA rupture (has a 45% mortality rate)
Intracardiac knotting
Endocarditis
Balloon rupture
Tricuspid/pulmonary valve injury
COMPLICATIONS OF THE PULMONARY ARTERY CATHETER
Because of its high mortality rate (45%) which risks factors of PA rupture should you be aware of?
Advanced age
Female
Primary HTN
Overinflation of the balloon (you should never need more than 1.5cc)
Distal tip being too far deep into the PA
COMPLICATIONS OF THE PULMONARY ARTERY CATHETER
When inflating PA catheter balloon, you realize than you need a lot less than 1.5cc of air to wedge. What would you conclude and what would do?
The catheter may be too far in
Deflate the balloon
Pull the catheter out
COMPLICATIONS OF THE PULMONARY ARTERY CATHETER
Which PA catheter complications are associated with the vascular access?
Hematoma
Air embolism
Thrombosis
Catheter shearing (embolization)
Pneumo/hemothorax
Vagal nerve or brachial plexus injury
Thoracic duct injury
COMPLICATIONS OF THE PULMONARY ARTERY CATHETER
Which PA catheter insertion site is associated with Vagal nerve or brachial plexus injury?
IJ approach
COMPLICATIONS OF THE PULMONARY ARTERY CATHETER
Which PA catheter insertion site is associated with Thoracic duct injury ?
Left IJ approach