GE Healthcare Arterial Pressure Variation Quick Guide
GE Healthcare
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Quick Guide
What is arterial pressure variation?
Positive pressure ventilation causes blood pressure
changes in the chest cavity: inspiratory phase increases
the pressure and expiratory phase decreases it.
The magnitude of these changes is dependent on the
uid status of the patient. In hypovolemic patients
these swings are higher in amplitude compared to
normovolemic or hypervolemic patients. This is a well
known phenomenon.
The arterial pressure variation algorithm looks for
respiratory changes in the arterial blood pressure.
It only uses the arterial blood pressure analysis and
does not use any other parameter to recognize the
respiratory cycle.
Arterial pressure variation can be used to assess uid
responsiveness continuously and without
extra procedures
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Arterial Pressure Variation
Arterial blood pressure variation in
GE patient monitoring
Systolic pressure variation (SPV) and pulse pressure
variation (dPP) reect respiratory changes in arterial
pressure during positive pressure ventilation.
SPV and dPP are calculated from the invasive arterial
blood pressure using the following equations:
SPV [mmHg]= SBPmax - SBPmin
dPP [%]= (PPmax - PPmin) / [(PPmax + PPmin) / 2] * 100
SBPmax and SBPmin represent the maximum and
minimum values of a systolic blood pressure over the
measurement period, respectively.
SPV
PPmax and PPmin represent the maximum and minimum
pulse pressures.
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min
(1, 2, 3)
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Values of SPV are represented in mmHg whereas dPP is a
percentage. Both numbers are computed once every ve
seconds. The measurement is continuous and trended in
the GE patient monitor. When the monitoring is started
it requires two respiratory cycles before the values are
shown on the screen.
The arterial pressure variation algorithm analyzes the
acquired invasive arterial blood pressure signal and,
therefore, it does not require any further equipment
besides the invasive blood pressure measurement kit.
Why monitor SPV/dPP?
One of the most common questions regarding
hemodynamics has to do with the patient’s uid
responsiveness: Will the patient’s stroke volume and
cardiac output improve with uid resuscitation?
In hypovolemic conditions respiratory variations in
stroke volume are higher than normal
responsive to uid therapy does not mean that the
patient really needs uid.
Monitoring arterial pressure variation, i.e. SPV/dPP, helps
to answer the question of uid responsiveness and can
be used to guide uid expansion therapy
parameters cannot, however, indicate what type of uid
is the most suitable for the therapy.
1
. However, being
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. SPV/dPP
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