Transcript Central Venous Pressures

Central Venous Pressures
In the Emergency Department
Central Venous Pressure…
What the heck is it?
Recall that Central Venous Pressure (CVP) is a good
reflection of right atrial pressure…
Which in turn is the major determinant of right
ventricular end diastolic volume – or preload.
CVP =
Right atrial pressure =
Preload
Influenced by:
1. Cardiac function
2. Venous return to the heart
Preload
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Initial stretching of
cardiac muscle
Measured by
ventricular end
diastolic volume or
pressure
Related to chamber
volume just prior to
contraction
Afterload
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The “load” the heart
must eject against
Closely related to
aortic pressure
When afterload
increases =increase in
end sys. vol. and
decrease in S.V.
Frank – Starling Curve
Factors Increasing Central Venous Pressure
Decreased cardiac output
Primarily a change in
compliance (C) or
volume (V)
V
Increased blood volume
V
Venous constriction
Changing from standing to supine
body posture
C
V
Arterial dilation
Forced expiration (e.g., Valsalva)
V,C
C
Muscle contraction (abdominal and
limb)
V, C
Q &A
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CVP is elevated by:
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1.
2.
3.
Decreased by:
1.
2.
3.
SO……While CVP cannot tell
the whole story, it can:
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Give a good approximation of:
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Hemodynamic status
Right-sided cardiac function
Cardiac function of the left side of the heart
(in pts with healthy heart and lungs)
CVP Measurement
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Measurement of BP
in right atrium and
vena cava
Central line threaded
so that the tip lies in
the lower third of
vena cava
Transduced
Normal 2-6 mm Hg
Assisting with Placement
1. Explain
procedure
5. VAMP
pressure
tubing
9. Note
waveform
2. Select
triple lumen
kit
6. Flush
tubing
10. Check
vitals
3. Sign
consent
4.Sterile
mask, gown
and gloves
8. Zero
transducer
7. Attach
pressure
cable & box
11. Heparin 12. Post
flush
procedure
PCXR
Other CVP Line Uses
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Rapid Infusion
Infusion of hypertonic solutions and meds
that could damage veins
Serial venous blood access
Two ways to read waveform:
1. Mean A wave or
2. Find Z-point
Q &A
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Find the Z point to
read a CVP waveform
when A waves are not
visible. T F
You may use regular
IV tubing on a CVP
line if transducer
tubing is not
available. T F
REMEMBER
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When the tricuspid
valve is open and the
R ventricle is full, the
ventricle, atrium, and
vena cava are all
connected.
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Therefore, that point
is the CVP
Q &A
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A Patients CVP
suddenly increased to
12. You should:
1. Increase IV fluids
2. Make the MD
aware
3. Check pt VS
THE END
Questions?