before exercise
'
Unusual DVP Waveforms
The shape of the waveform can vary
considerably along the physiological range as
presented above.
There are some examples where the
waveform is extremely difficult to interpret
such as the one presented opposite.
The calculation of SI and RI should be treated with caution when an
unusual waveform is seen. If possible, such waveforms should be
saved, the patient details noted and CareFusion informed.
Repeatability and Reproducibility
The table bellow summarizes the coefficient of variation obtained by
different research groups. This is comparable with other
physiological measurements and the variation represents the
dynamic nature of the cardiovascular system.
Paper
Millasseau et al.
Subject
numbers
8
Status
Healthy
SI cv%
9.6%
RI cv%
'
5
Woodman et al.
30
15 CAD/15 healthy
17.8% (15%)
after exercise
'
10,11
Laucevicius et al.
23
Healthy
Inter-
operator
14.4%
7.0%
32
'
12
Intra-
operator
11.9%
4.8%