invasive monitoring

1. Pulmonary Artery Catheter
Speaker: Dr. Arun
Moderator Asst Prof. Dr. Madhavakrishna
Professor: Dr. Kumudha Lingaraj

2.  Introduction
 Indications
 Contraindications
 Preparation
 Technique
 Interpretation of physiological values and waveforms
 Complications

4. Indications
 Diagnostic:
 Differentiation among causes of shock
 Differentiation between mechanisms of pulmonary edema
 Evaluation of pulmonary hypertension
 Diagnosis of pericardial tamponade
 Diagnosis of right to left intracardiac shunts
 Unexplained dyspnea

5.  Therapeutic:
 Management of perioperative patients with unstable cardiac status
 Management of complicated myocardial infarction
 Management of patients following cardiac surgery/high risk surgery
 Management of severe preecclampsia
 Guide to pharmacologic therapy
 Burns/ Renal Failure/ Heart failure/Sepsis/ Decompensated cirrhosis
 Assess response to pulmonary hypertension specific therapy

6. Contraindication:
Absolute:
 Tricuspid and pulmonary valvular
stenosis
 Tetrology of fallot
 Infection at insertion site
 Presence of RV assist device
 Insertion during CPB
 Lack of consent
Relative:
 Coagulopathy
 Thrombocytopenia
 Electrolyte disturbances
(K/Mg/Na/Ca)
 Severe Pulmonary HTN

7. Preparation
 Patient has to be monitored with continuous ECG throughout the procedure, in
supine position regardless of the approach
 Aseptic precautions must be employed
 Cautions should be taken while cannulating via IJV/ Subclavian vein

8.  Equipments:
 2% chlorhexidine skin preparation solution
 Sterile gown, gloves, face shield and cap
 Sterile gauze pads
 1% lidocaine -5 cc
 Seeker needle 23G
 Introducer needle  18G
 J-tip guidewire
 Transduction tubing
 Sterile catheter flush solution
 Sheath
 Pulonary catheter
 Sterile sleeve for catheter
 2-0 silk suture
 Sterile dressing

10. Catheters:
The standard PAC has 7.0,7.5 or 8.0 Fr
circumference and in 110cm in length with distances
marked at 10cm intervals.
DOUBLE LUMEN- for ballon inflation and PA
pressure
TRIPLE LUMEN- above 2 + RA pressure
QUADRUPLE LUMEN- above 3 + THERMISTOR for
thermodilution {CO measurement}
FIVE LUMEN –additional lumen for drug infusion

12. Technique
1. Aseptic precautions undertaken
2. Local infiltration done
3. Check balloon integrity by inflating with 1.5ml of air
4. Check lumens patency by flushing with saline 0.9%
5. Cover catheter with sterile sleeve provided
6. Cannulate vein with Seldinger technique
7. Place sheath
8. Pass catheter through sheath with tip curved towards the heart

13. 9. Once tip of catheter passed through introducer sheath inflate balloon at level of
right ventricle
10. The progress of the catheter through right atrium and ventricle into pulmonary
artery and wedge position can be monitored by changes in pressure trace
11. After acquiring wedge pressure  deflate balloon

14. Interpretations of wave forms

16. Physiological Measurements:
Direct measurements of the following can be
obtained from an accurately placed pulmonary artery
catheter(PAC)
Central Venous Pressure(CVP)
Right sided intracardiac pressures(RA/V)
Pulmonary artery pressure(Pap)
Pulmonary artery occlusion pressure (PAOP)
Cardiac Output
Mixed Venous Oxygen Saturation(SvO2)

17. Indirect measurements that are possible:
Systemic Vascular Resistance
Pulmonary Vascular Resistance
Cardiac Index
Stroke volume index
Oxygen delivery
Oxygen uptake

18. Calculation of Cardiac Output:
Thermodilution versus Ficks method
•Thermodilution: Add an indicator substance (5ml of dextrose or
saline) that is cooler than blood. Indicator in injected through the
proximal port of the PA catheter and mixes with the blood in the
RV. The mixing lowers the temperature of the flowing blood which
is carried to the distal thermistor port. The thermistor records the
temperature change and electronically displays a temperature/time
curve. The area under the curve is inversely proportional to the
flow rate in the pulmonary artery which equals the cardiac output in
absence of intracardiac shunt
-sources of error with thermodilution are seen with
tricuspid regurgitation and intracardiac shunts

19. Fick’s Method
 General principle: the release or uptake of a substance by
an organ equals the product of the bloodflow through
that organ times the difference of arteriovenous
concentrations of that substance.
 CO= O2 consumption (ml/min)
------------------------------------------------------------
---
arterial O2 content(PCWP)-mixed venous (PA) O2
content
 O2 consumption varies according to individual, by age
and sex. Usually estimated as being 250mL for a 70kg
male. Generally estimated at 130mL x BSA
 Blood O2 content=% saturation X Hb x 1.39 ml O2/gm
Hb
 Errors: assumptions of O2 consumption, wont work at all
with intracardiac shunts. But works better with TR

22. SVR=(MAP-CVP)*80 {normal 900-1400 dyne/sec/cm2}
CO

23. Pulmonary arterial occlusion pressure:
 Once catheter tip has reached PA, it should be advanced until
PAOP is identified by decrease in pressure and change in
waveform
The balloon should then be deflated and PA tracing should
reappear
If PCOP tracing persists catheter should be withdrawn with
definitive PA tracing obtained

24.  Final position of the catheter within PA must be such that PCOP tracing is
 obtained whenever 75-100% of 1.5ml maximum volume of balloon is
 insufflated.
 If < 1ml of air is injected and PAOP is seen then it is overwedged  needs to be
withdrawn
 If after maximal inflation fails to result in PCOP tracing or after 2-3 seconds delay 
too proximal – advanced with balloon inflated

25.  PCWP/PAOP  interprets Left atrial pressures
more importantly – LVEDP
PAEDP ~ PAOP ~ PVP ~ LAP ~ LVEDP
 Best measured in
 Supine position
 At end of expiration
 Zone 3 (most dependent region)
 Normal PCWP- 6-15 mmHg ; Mean :9mmHg

26.  Abnormal PAOP:
Increased LVEDP  Increased PAOP
LV systolic HF
LV Distolic HF
Mitral and Aortic valve disease
Hypertrophic cardiomyopathy
Hypervolemia
Large R-L shunts
Pericardial disease

27.  Decreased PCWP:
 Hypovolemia
 Obstructive shock due to large pulmonary embolus
 Abnormal waveforms
 Large a waves:
 MS
 LV systolic /diastolic function
 LV volume overload
 MI
 Large v waves - MR

28. Complications
 General:
 Immediate:
 Bleeding
 Arterial Puncture
 Air embolism
 Thoracic duct injury ( L side)
 Pneumothorax/hemothorax
 Delayed:
 Infections
 Thrombosis

29.  Related to insertion of PAC:
 Arrhythmias (most common- Ventricular/ RBBB)
 Misplacement
 Knotting
 Myocardial/valve/vessel rupture
 Related to maintenance and use of PAC:
 Pulmonary artery perforation
 Thromboembolism
 Infection

31. THANK YOU. . .