Biomedical Engineering Reference
In-Depth Information
Fig. 8.21
The dependency
with age for (
top half
)the
constant
C
and (
bottom half
)
the fractal dimension
F
d
.
Blue stars
denote the data
extracted from PPP plots,
while the
red circles
denote
the data extracted from the
PV plots
values are obtained for each patient, in each data set. The resulting data has been
analyzed against biometric values in order to verify dependence, and an illustra-
tive example is given in Fig.
8.21
, for the age dependence. We found no consistent
dependency with age, height, and weight, respectively.
Next, the trends of the fractal dimension calculated for each group are given in
Fig.
8.22
by means of PV loops, and in Fig.
8.23
by means of PPP loops, respec-
tively. Finally, the loci of the identified power-law model parameters from relation
(
8.23
)aregiveninFig.
8.24
and the values are listed in Table
8.4
.
In its most simple representation, the respiratory system can be represented as a
series connection of a resistance
R
e
and a compliance
C
e
. It assumes patient's respi-
ratory muscles inactive and the external equipment is driving the flow into the lungs
[
53
,
112
,
125
]. The driving pressure
P(t)
generates flow
Q(t)
across the resistance
and the volume
V(t)
changes in the compliance. If
P
r
(t)
and
P
e
(t)
are the resistive
and elastic pressure drops, respectively, we have
P
r
(t)
Q(t)
;
V(t)
P
e
(t)
R
r
=
C
r
=
=
+
and
P(t)
P
e
(t)
P
r
(t).
(8.24)
