U.S. patent application number 12/278662 was filed with the patent office on 2009-07-23 for peritoneal dialysis system.
This patent application is currently assigned to DEBIOTECH S.A.. Invention is credited to Diego Mastalli, Alfio Quarteroni, Paolo Zunino.
Application Number | 20090187139 12/278662 |
Document ID | / |
Family ID | 38080801 |
Filed Date | 2009-07-23 |
United States Patent
Application |
20090187139 |
Kind Code |
A1 |
Mastalli; Diego ; et
al. |
July 23, 2009 |
PERITONEAL DIALYSIS SYSTEM
Abstract
Peritoneal dialysis system comprising pumping means, therapy
data receiving means and processing means, said processing means
being designed to process said therapy data and to impart a
switching sequence to said pumping means characterized by the fact
that said processing means are furthermore designed to impart a
specific exchange profile for each exchange cycle.
Inventors: |
Mastalli; Diego; (Lausanne,
CH) ; Quarteroni; Alfio; (St-Sulpice, CH) ;
Zunino; Paolo; (Milano, IT) |
Correspondence
Address: |
NIXON & VANDERHYE, PC
901 NORTH GLEBE ROAD, 11TH FLOOR
ARLINGTON
VA
22203
US
|
Assignee: |
DEBIOTECH S.A.
Lausanne
CH
|
Family ID: |
38080801 |
Appl. No.: |
12/278662 |
Filed: |
February 7, 2007 |
PCT Filed: |
February 7, 2007 |
PCT NO: |
PCT/IB07/50406 |
371 Date: |
December 8, 2008 |
Current U.S.
Class: |
604/29 |
Current CPC
Class: |
G16H 20/17 20180101;
A61M 1/28 20130101; G16H 20/40 20180101; A61M 2205/33 20130101;
A61M 1/282 20140204; A61M 2205/52 20130101 |
Class at
Publication: |
604/29 |
International
Class: |
A61M 1/28 20060101
A61M001/28 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 8, 2006 |
IB |
2006/050412 |
Claims
1. Peritoneal dialysis system comprising pumping means, therapy
data receiving means and processing means, said processing means
being designed to process said therapy data and to impart a
switching sequence to said pumping means characterized by the fact
that said processing means are furthermore designed to impart a
specific exchange profile for each exchange cycle.
2. Peritoneal dialysis system according to claim 1 wherein said
processing means are designed to vary the volume of liquid injected
in each exchange cycle.
3. Peritoneal dialysis system according to claim 1 wherein said
processing means are designed to vary the volume of liquid
extracted in each exchange cycle.
4. Peritoneal dialysis system according to claim 1 wherein said
processing means are designed to vary the dwell time in each
exchange cycle.
5. Peritoneal dialysis system according to claim 1 wherein said
therapy data include the total therapy time (T.sub.tot), the total
dialysate volume available for the peritonal dialysis session
(V.sub.tot), the flow rate of the pumping means (q), the maximum
dialysate volume that can be contained in the peritoneal cavity
(V.sub.max), the minimum dialysate volume reachable in the
peritoneal cavity (V.sub.min) and the number of cycles of the
therapy (N).
6. Peritoneal dialysis system according to claim 1 wherein said
processing means are capable to determine each dwell time TD(i)
according to the following system of equations: { TD ( i + 1 ) = (
.alpha. + .gamma. i ) TD ( i ) , i = 1 , , N - 1 TD ( 1 ) = T tot -
2 V tot q 1 + j = 1 N - 2 i = 1 j .alpha. + .gamma. i ##EQU00005##
where, .alpha. is the parameter which fixes a base for the ratio T
D(i+1)/T D(i), D is the parameter which allows to change the ratio
T D(i+1)/T D(i) with respect the number of the cycle, TD.sub.(1) is
computed to respect the total therapy time T.sub.tot.
7. Peritoneal dialysis system according to claim 1 wherein said
processing means are capable to determine each volume injected
DV(i) according to the following system of equations: { DV ( i + 1
) = ( .beta. + .delta. i ) DV ( i ) , i = 1 , , N - 2 DV ( 1 ) = V
tot 1 + j = 1 N - 2 i = 1 j .beta. + .delta. i ##EQU00006## where,
.beta. is the parameter which fix a base for the ratio DV(i+1)=DV
(i), .delta. is the parameter which allows to change the ratio
DV(i+1)=DV (i) with respect the number of the cycle. V D(1) is
computed to respect the total dialysate volume Vtot available.
8. Peritoneal dialysis system according to claim 1 claims wherein
said processing means are designed to determine the switching
sequence as follows: t0=0, t.sub.k+1=t.sub.k+DT(k); K=0; . . . ;
3N+1 where DT(k) represents the time needed in each exchange cycle
for the injection phase, the dwell and the extraction phase.
9. Method for determining a peritoneal dialysis treatment
characterized by the fact that the liquid exchange profile is
varying from one exchange cycle to the other.
10. Method according to claim 9 wherein the dwell time TD varies
from one exchange cycle to the other.
11. Method according to claim 9 wherein the volume of liquid
injected DV varies from one exchange cycle to the other.
12. Method according to claim 9, wherein the volume of liquid
extracted DV varies from one exchange cycle to the other.
13. Method according to claim 9 wherein each dwell time TD(i) is
determined according to the following system of equations: { TD ( i
+ 1 ) = ( .alpha. + .gamma. i ) TD ( i ) , i = 1 , , N - 1 TD ( 1 )
= T tot - 2 V tot q 1 + j = 1 N - 2 i = 1 j .alpha. + .gamma. i
##EQU00007## where, .alpha. is the parameter which fixes a base for
the ratio T D(i+1)/T D(i), .beta. is the parameter which allows to
change the ratio T D(i+1)/T D(i) with respect the number of the
cycle, TD.sub.(1) is computed to respect the total therapy time
T.sub.tot.
14. Method according to claim 8 wherein each volume injected DV(i)
is determined according to the following system of equations: { DV
( i + 1 ) = ( .beta. + .delta. i ) DV ( i ) , i = 1 , , N - 2 DV (
1 ) = V tot 1 + j = 1 N - 2 i = 1 j .beta. + .delta. i ##EQU00008##
where, .beta. is the parameter which fix a base for the ratio
DV(i+1)=DV (i), .delta. is the parameter which allows to change the
ratio DV(i+1)=DV (i) with respect the number of the cycle. V D(1)
is computed to respect the total dialysate volume Vtot available.
Description
FIELD OF INVENTION
[0001] The present invention relates to a peritoneal dialysis
system which can conduct a specific peritoneal dialysis
treatment.
[0002] The invention also relates to a method for determining a
peritoneal dialysis treatment which is specific for each
patient.
STATE OF THE ART
[0003] During a peritoneal dialysis session a liquid, the so called
dialysate, is introduced many times into the peritoneal cavity in
order to exchange toxins and liquid with the blood. The exchange
takes place through the net of capillaries within the peritoneal
membrane.
[0004] Examples of standard treatments are: [0005] APD (Automatic
Peritoneal Dialysis), [0006] CAPD (Continuous Ambulatory Peritoneal
dialysis), [0007] CCPD (Continuous Cycling Peritoneal Dialysis),
[0008] TPD (Tidal Peritoneal Dialysis).
[0009] All state of the art treatments are characterized by
exchanges with fixed volumes and dwells. However, those treatments
are not taking into account the permanent change of patient
characteristics after each exchange cycle.
[0010] It would therefore be more efficient to have another
treatment which better follow the changes of patient
characteristics during a treatment.
DESCRIPTION OF THE INVENTION
[0011] The above cited problems are solved with the peritoneal
dialysis system according to the invention which comprises pumping
means, therapy data receiving means and processing means, said
processing means being designed to process said therapy data and to
impart a switching sequence to said pumping means. The system
according to the invention is characterized by the fact that said
processing means are furthermore designed to impart a specific
exchange profile for each exchange cycle.
[0012] In other words, the system according to the invention is
designed to vary the exchange cycles during the treatment in order
to better match the patient characteristics in a dynamic way.
[0013] In the following text, the treatment according to the
invention is called DPD for Dynamic Peritoneal Dialysis.
[0014] The variation of the exchange cycles can be done in varying
the injected volume of liquid and/or the dwell times and/or the
extracted volume of liquid.
[0015] A more detailed description of the invention is presented
below together with the following figures:
[0016] FIG. 1 illustrates the volume exchange with the peritoneal
cavity.
[0017] FIG. 2 illustrates a state-of-the-art therapy
[0018] FIG. 3 illustrates a DPD treatment according to the
invention.
[0019] Let us introduce the notation that will be used in relation
with the DPD pattern. We remind that the injection-dwell-extraction
pattern in peritoneal dialysis (PD) is made by several cycles i=1,
. . . , N (see FIG. 1). The Vmax and Vmin in FIG. 1 represent
respectively the maximum volume that can be introduced in the
peritoneal cavity and the minimum volume reachable. In each cycle
some fresh dialysate is injected (DVi), and extracted from the
patient after a given dwell time (TDi). We refer to FIG. 2 for an
explanation of the notation. The standard therapies nowadays in use
APD, CAPD, CCPD, TPD etc. . . . , have a common property: the dwell
times DTi and the injected volumes DVi are fixed with respect the
number of cycle i=1; . . . ; N. It means that:
DT(1)=DT(2)= . . . =DT(N)
DV(1)=DV(2)= . . . =DV(N)
[0020] This is just the case represented in FIG. 2. It is obvious
that by this way the standard PD treatments are somewhat rigid
because there is no possibility to get DT(1).noteq.DT(2).noteq. . .
. .noteq.DT(N) and or DV(1).noteq.DV(2).noteq. . . . .noteq.DV(N).
Conversely, the DPD treatments provide this possibility and
guarantee more flexibility. We refer to FIG. 3 as example of DPD.
The reader should recognize easily the variability in dwell times
and volumes that distinguish DPD with respect standard therapies by
a comparison of FIGS. 2 and 3.
[0021] In order to build a DPD pattern we consider a set of input
data concerning the therapy.
[0022] Preferably we consider as input the total therapy time
(T.sub.tot), the total dialysate volume available for the peritonal
dialysis session (V.sub.tot), the flow rate of the pumping means
(q), the maximum dialysate volume that can be contained in the
peritoneal cavity (V.sub.max), the minimum dialysate volume
reachable in the peritoneal cavity (V.sub.min) and the number of
cycles of the therapy (N).
[0023] The DPD method provides the injection-dwell-extraction
pattern taking into account a set of constraints: [0024] the
therapy begin filling the peritoneal cavity up to Vmax, [0025] the
therapy must not be longer than the fixed total time Ttot,
[0025] i = 1 N TD ( i ) = T tot - 2 V tot q ##EQU00001## [0026] the
total dialysate volume injected must be equal to the total amount
Vtot available,
[0026] i = 1 N - 1 VD ( i ) = V tot - ( V max - V min )
##EQU00002## the dwell times must be positive,
TD(i)>0, i=1, . . . N [0027] the volume of dialysate into the
peritoneal cavity must respect the lower and the upper bounds Vmin
and Vmax
[0027] 0<DV(i).ltoreq.V.sub.max-V.sub.min, i=1, . . . , N-1
[0028] the therapy end emptying the peritoneal cavity from Vmax to
Vmin, [0029] Nmin is the minimum number of cycles needed to use the
dialysate available: Nmin=ceil(Vtot=(Vmax/Vmin)).
[0030] Based on the previous input data and constraints the DPD
strategy provides the injection-dwell-extraction through the
following iterative relations. The first set is used to choose the
dwell times T D(i) of the DPD pattern as follows:
{ TD ( i + 1 ) = ( .alpha. + .gamma. i ) TD ( i ) , i = 1 , , N - 1
TD ( 1 ) = T tot - 2 V tot q 1 + j = 1 N - 2 i = 1 j .alpha. +
.gamma. i ##EQU00003##
where, [0031] .alpha. is the parameter which fix a base for the
ratio T D(i+1)/T D(i), .beta. is the parameter which allows to
change the ratio T D(i+1)/T D(i) with respect the number of the
cycle, [0032] TD(1) is computed to respect the total therapy time
Ttot
[0033] The second set is used to choose the volumes injected DV(i)
of the DPD pattern as follows
{ DV ( i + 1 ) = ( .beta. + .delta. i ) DV ( i ) , i = 1 , , N - 2
DV ( 1 ) = V tot 1 + j = 1 N - 2 i = 1 j .beta. + .delta. i
##EQU00004##
where, [0034] .beta. is the parameter which fix a base for the
ratio DV(i+1)=DV (i), [0035] .delta. is the parameter which allows
to change the ratio DV(i+1)=DV (i) with respect the number of the
cycle [0036] V D(1) is computed to respect the total dialysate
volume Vtot available. If .gamma.=0, .alpha.=1 we obtain
TD(i+1)=TD(i) and If .delta.=1, .beta.=1 we obtain DV (i+1)=DV (i).
This parameters set up allows to obtain standard treatments by the
DPD methodology.
[0037] In order to guarantee the execution of the DPD pattern to
pumping means the outputs produced are: [0038] the dwell sequence T
D(i); i=1; . . . ; N, [0039] the volume sequence DV(i); i=1; . . .
; N-1, [0040] the switching sequence for the pumping means
execution,
[0040] t0=0;
tk+1=tk+DT(k); k=0; . . . ; 3N+1
where DT (k) represent the time needed in each cycle for the
injection phase, the dwell and the extraction phase.
[0041] Of course the invention is not limited to the above
examples. For instance other equations can be used for defining the
varying parameters TD and DV.
* * * * *