1. Pulmonary artery catheter for cardiac pressure monitoring
and its role in anesthetic practice
Dr. Shalini Saini
University College of Medical Sciences & GTB
Hospital, Delhi
4. Pulmonary artery catheter
• Standard : 7-9 Fr circumference
• 110cm length at 10cm intervals
• Four internal lumen-
1. Distal-pulmonary artery
pressure monitoring
2. Proximal-30cm for CVP
monitoring
3. It leads to balloon near the tip
4. It houses wires for a
temperature thermistor
5. Uses of pulmonary artery catheter
• Assessment of volume status in patients undergoing major
surgeries
• Cardiac output measurement by thermodilution technique
• Various hemodynamic parameters-pulmonary artery
pressure, pulmonary capillary wedge presssure,CVP,systemic
vascular resistance, pulmonary vascular resistance.
• Respiratory or oxygen transport measurement-mixed venous
oximetry.
6. Insertion
Sites of insertion
• Right internal jugular vein (preferred)
• Left internal jugular vein (2nd choice)
• Subclavian vein (disadvantages)
• External jugular vein ( superficial location but tortous)
• Antecubital vein
• Femoral vein
*After successful venous cannulation, there might be difficulty in
advancement of the catheter due to abnormal venous anatomy.
- most common: persistence of left superior vena cava.
7. RA RV PA
IJV-right 20cm 30cm 45cm
left 25cm 35cm 50cm
Antecubital –rt 50cm 65cm 80cm
-lt 55cm 70cm 85cm
Femoral v 40cm 50cm 65cm
Subclavian v 10cm 25cm 40cm
Distances to right atrium, right ventricle and pulmonary artery
8. Pressure Average (mm Hg) Range (mm Hg)
Right Atrium
a wave 6 2-7
v wave 5 2-7
Mean 3 1-5
Right Ventricle
Peak systolic 25 15-30
End-diastolic 6 1-7
Pulmonary Artery
Peak systolic 25 15-30
End-diastolic 9 4-12
Mean 15 9-19
Pulmonary Artery Wedge
Mean 9 4-12
Left Atrium
Mean 8 2-12
Left Ventricle
Peak systolic 130 90-140
End-diastolic 8 5-12
Normal Cardiovascular Pressures
9. Wave form recorded during passage of pulmonary artery catheter
• Right atrial pressure resembles central venous pressure waveform
• Right ventricular pressure shows higher systolic pressure
• Pulmonary artery pressure shows diastolic step up
• Pulmonary artery wedge pressure similar morphology as right atrial pressure but a,c
v waves appear later
10. Temporal relationships between systemic arterial
pressure,pulmonary artery pressure, central venous pressure and
pulmonary artery wedge pressure
-PAP upstroke precedes radial artery pressure upstroke
-Wedge pressure a wave follows ECG R wave
11. Three-zone model of pulmonary vasculature
-described by West and
colleague
-tip of PAC should lie in
zone3
-supine position favours
zone3 condition
13. Indications
1. Patients undergoing cardiac surgery with
• Poor left ventricular compliance(ejection fration <0.4, LVEDP>18mm hg)
• Left wall motion abnormality
• Recent MI (<6 Months)
• Left main coronary lesion
• Valvular lesion
• Presence of pulmonary artery hypertension
14. 2. Major procedures involving large fluid shifts or blood loss
in patients with-
• Cardiogenic or septic shock or with multiple organ failure
• Hemodynamic instability requiring ionotropes or intra-aortic
balloon counterpulsation
• Hepatic transplantation
• Massive ascites requiring major surgery
• Surgery of aorta requiring cross-clamping
• Large abdomino-perineal resection etc.
15. 3. Intensive care unit
• To measure pulmonary artery and pulmonary capillary wedge
pressure
• To measure cardiac output by thermodilution
• To obtain intracavitary electrocardiogram
• To perform atrial or ventricular pacing
• To allow infusion of drugs
• To perform angiography
• To detect venous air embolism
4. Continous mixed venous oximetry
- To assess the adequacy of perfusion
16. Recommendations for perioperative use of PACs
(AHA 2007 guidelines)
• Class 2b-(level of evidence:B)
Use of PAC is reasonable in patients at risk for major hemodynamic
disturbances easily detected by PAC. However, decision must be based
on three parameters-
a. disease
b. surgical procedure
c. practice setting (Experience & interpretation)
• Class 3-(level of evidence:A)
Routine use of PAC perioperatively, especially low risk of hemodynamic
disturbances, is not recommended.
17. Pulmonary Artery Catheterisation and outcome
controversies
• PAC use in 5735 patients in first 24 hrs intensive care associated with
increased mortality, hospital stay and cost.(Connors etal,1997)
• Three trials including 3468 patients showed no effect on mortality but
higher incidence of adverse effects(Harvey etal,2005; The ESCAPE
Trial,2005; Sandham etal,2003)
• A review of 53312 patients from National Trauma Data Bank showed
-No mortality benefit in patients treated with PAC
-Injury scale greater: mortality decreased(Friese etal,2006)
• In mixed medical and surgical population,APACHE scores
<25 -increased mortality
>31 -significant benefit (Chittock etal,2004)
18. • A group of experienced cardiac anesthesiologists and surgeons
blinded to information from pulmonary artery catheterisation
during CABG surgery were unaware of 65% of severe
hemodynamic abnormalities.(Waller and Kaplan)
• ICU physicians were unable to accurately predict hemodynamic
data on clinical grounds and 60% made at least one change
in therapy and 33% changed their diagnosis based on PAC
data.(Iberti and Fisher)
19. Contraindications (Kaplan)
Absolute contraindications
• Tricuspid or pulmonary stenosis
• Right atrial or ventricular mass
• Tetralogy of Fallot
Relative contraindications
• Severe arrhythmias
• Coagulopathy
• Newly inserted pacemaker wires
20. Complications
1. Catheterisation
a. Arrythmia-primary complication
-most common premature ventricular contractions
-ventricular fibrillation
b. Right bundle branch block
c. Complete heart block
Treatment- balloon deflated and catheter withdrawn to right
atrium
21. 2. Catheter residence
a. Catheter knotting -suspected when difficulty in withdrawing
-diagnosed with chest x-ray
-untied by radiologist
b.Thromboembolism –rising incidence
-increased with antifibrinolytic drugs
c. Pulmonary infarction
d. Infection ,endocarditis
e. Endocardial damage, cardiac valve injury
f. Thrombocytopenia (heparin induced)
22. g. Pulmonary artery rupture
-Incidence: 0.064%-0.20%
-Increased risk: female sex, hypothermia, anticoagulation,
advanced age, pulmonary hypertension, mitral stenosis,
coagulopathy, distal placement catheter, balloon hyperinflation
-Hallmark:hemoptysis and exsanguination
-Treatment:
1. Resuscitation-adequate oxygenation and ventilation
2. If hemorrhage minimal,with coagulopathy-correct coagulopathy
3. Protection of uninvolved lung by-tilting patient to affected side,
placement of double lumen endotracheal tube
4. Stop hemorrhage- apply PEEP, Bronchial blockers, resection.
5. Severe hemorrhage with recurrent bleeding-transcatheter coil
embolisation.
23. Abnormal pressure waveforms
A. Artifact
Overwedging occurs
when balloon
overinflated/distal
migration of
cathter/eccentric balloon
inflation.
24. B.Pathophysiologic changes
1.Mitral regurgitation
-Tall v waves in waveform
with bifid appearance
-PAP upstroke steeper
-Wedge pressure prominent v
wave with gradual upstroke
-Wedge pressure overestimates
left ventricular filling pressure
-Tall v wave:hypervolemia,CHF,
VSD.
25. 2.Mitral stenosis
-Mean wedge pressure
increased
-y descent slurred due to
obstruction to bloood flow
-Similar abnormalities-left
atrial myxoma, left ventricle
infarction, pericardial
constriction,aortic stenosis,
systemic hypertension
26. 3.Pericardial constriction
-prominent a and v waves
-steep x and y descent
-M or W configuration in CVP trace
-diastolic ‘dip and plateau’ pattern or
square root sign due to early diastolic
ventricular filling
-mid diastolic h wave (plateau) due to
interruption in flow due to restrictive
shell
27. 4.Myocardial ischemia
• First time used in patient with
acute MI.
• PAP normal relatively
• PAWP slightly elevated
• PAWP morphology abnormal
-Tall a waves due to diastolic
dysfunction
28. Condition Site of Discrepancy Cause of Discrepancy
Positive end-expiratory pressure Mean PAWP > mean LAP
Creation of lung zone 1
or 2 or pericardial
pressure changes
Pulmonary arterial hypertension PADP > mean PAWP
Increased pulmonary
vascular resistance
Pulmonary veno-occlusive disease Mean PAWP > mean LAP
Obstruction to flow in
large pulmonary veins
Mitral stenosis Mean LAP > LVEDP
Obstruction to flow
across the mitral valve
Mitral regurgitation Mean LAP > LVEDP
Retrograde systolic v
wave raises mean atrial
pressure
Ventricular septal defect Mean LAP > LVEDP
Antegrade systolic v
wave raises mean atrial
pressure
Tachycardia PADP > mean LAP > LVEDP
Short diastole creates
pulmonary vascular and
mitral valve gradients
Overestimation of Left Ventricular End-Diastolic Pressure
29. Condition Site of Discrepacy Cause of Discrepancy
Diastolic dysfunction Mean LAP < LVEDP Increased end-diastolic a wave
Aortic regurgitation LAP a wave < LVEDP
Mitral valve closure before
end-diastole
Pulmonic regurgitation PADP < LVEDP
Bidirectional runoff for
pulmonary artery flow
Right bundle branch block PADP < LVEDP
Delayed pulmonic valve
opening
After pneumonectomy PAWP < LAP or LVEDP
Obstruction of pulmonary
blood flow
Underestimation of Left Ventricular End-Diastolic Pressure
30. Additional uses of pulmonary artery catheter
1. Thermodilution cardiac output monitoring
• Principle: Stewart-Hamilton equation
Q = V(Tb-Ti)K1.K2
Tb(t)dt
Q = Cardiac output
V = Injectate volume
Tb = Blood temperature
Ti = Injectate temperature
K1 = Density factor: (sp heat)(sp gravity)injectate
(sp heat)(sp gravity)blood
K2 = A computation constant which includes heat change in
transit,dead space of the catheter,injection rate, adjusts units to l/min
Tb(t)dt = change in blood temperature as a function of time
