U.S. patent application number 13/182934 was filed with the patent office on 2012-05-03 for interactive, wireless reduced-pressure dressings, methods, and systems.
This patent application is currently assigned to KCI Licensing, Inc.. Invention is credited to Richard Daniel John Coulthard, Christopher Brian Locke.
Application Number | 20120109034 13/182934 |
Document ID | / |
Family ID | 45994285 |
Filed Date | 2012-05-03 |
United States Patent
Application |
20120109034 |
Kind Code |
A1 |
Locke; Christopher Brian ;
et al. |
May 3, 2012 |
INTERACTIVE, WIRELESS REDUCED-PRESSURE DRESSINGS, METHODS, AND
SYSTEMS
Abstract
Systems, methods, and dressings are presented that involve using
a RFID device in a dressing to provide pressure data or other data
to a remote base unit. The dressing is an interactive dressing. The
reduced pressure in the dressing may be monitored and used to
control delivery of reduced pressure. In one instance, the pressure
data at each dressing allows a plurality of tissue sites to be
monitored and used with as single remote base unit. In another
instance, devices and methods for assuring a proper pairing of
reduced-pressure dressings and remote base units are also
presented. Other systems, methods, and dressings are presented.
Inventors: |
Locke; Christopher Brian;
(Bournemouth, GB) ; Coulthard; Richard Daniel John;
(Verwood, GB) |
Assignee: |
KCI Licensing, Inc.
|
Family ID: |
45994285 |
Appl. No.: |
13/182934 |
Filed: |
July 14, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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61407194 |
Oct 27, 2010 |
|
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61418730 |
Dec 1, 2010 |
|
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61445383 |
Feb 22, 2011 |
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61445338 |
Feb 22, 2011 |
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Current U.S.
Class: |
602/42 ;
604/319 |
Current CPC
Class: |
A61M 1/0031 20130101;
A61F 13/00068 20130101; Y10T 29/49018 20150115; A61M 2205/3344
20130101; A61M 2205/3576 20130101; A61F 13/02 20130101; A61F
2013/00536 20130101; A61M 2205/6054 20130101; A61M 1/0092 20140204;
A61F 2013/0094 20130101; A61M 2205/3592 20130101; A61F 13/00055
20130101; A61M 1/0023 20130101; A61M 1/009 20140204; A61F 13/0216
20130101; A61M 1/0088 20130101; A61F 2013/00174 20130101; A61M
1/0066 20130101 |
Class at
Publication: |
602/42 ;
604/319 |
International
Class: |
A61M 1/00 20060101
A61M001/00; A61F 13/00 20060101 A61F013/00 |
Claims
1. A method for treating at least one tissue site with reduced
pressure, the method comprising: disposing a first, wireless,
reduced-pressure dressing proximate to a first tissue site, wherein
the first, wireless, reduced-pressure dressing comprises: a
distribution manifold for placing adjacent to the tissue site and
for providing reduced pressure to the tissue site, a sealing member
covering at least a portion of the distribution manifold, a first
processor, a RFID antenna coupled to the first processor, and a
first sensor coupled to the first processor, wherein the first
sensor comprises a pressure sensor; providing a remote base unit
comprising a RFID reader; providing reduced pressure to the
distribution manifold; transmitting a first pressure inquiry signal
from the RFID reader to the first, wireless, reduced-pressure
dressing; receiving a first pressure message signal from the first,
wireless, reduced-pressure dressing in response to the first
pressure inquiry signal; and wherein the first pressure message
signal is wirelessly transmitted by the RFID antenna to the remote
base unit without requiring any pressure sensing lumens in the
reduced-pressure delivery conduit.
2. The method of claim 1, further comprising determining if the
first pressure message signal is greater (on an absolute pressure
scale) than a target pressure, and if greater than the target
pressure, then activating the reduced-pressure source, and if less
(on an absolute pressure scale) than the target pressure, then
deactivating the reduced-pressure source.
3. The method of claim 1, wherein the method further comprises:
disposing a second, wireless, reduced-pressure dressing adjacent to
a second tissue site; transmitting a second pressure inquiry signal
from the RFID reader to the second, wireless, reduced-pressure
dressing; and receiving a second pressure message signal from the
second, wireless, reduced-pressure dressing in response to the
second pressure inquiry signal.
4. The method of claim 1, further comprising a second sensor
coupled to the first processor, wherein the second sensor comprises
a temperature sensor.
5. A system for treating at least one tissue site with reduced
pressure, the system comprising: a first, wireless,
reduced-pressure dressing for disposing proximate to the tissue
site, wherein the first, wireless, reduced-pressure dressing
comprises: a distribution manifold, a sealing member covering at
least a portion of the distribution manifold, a RFID antenna, a
first processor coupled to the RFID antenna, and a first sensor
coupled to the first processor, a remote base unit comprising a
RFID reader and a second processor coupled to the RFID reader; and
a reduced-pressure source fluidly coupled to the distribution
manifold.
6. The system of claim 5, wherein the first sensor is a pressure
sensor.
7. The system of claim 6, wherein the first, wireless,
reduced-pressure dressing further comprises a second sensor
selected from the group: temperature sensor, pH sensor, a humidity
sensor, a volatile organic compound sensor, a blood sensor, and a
growth factor sensor.
8. The system of claim 5, wherein the reduced-pressure source is
coupled to the remote base unit and wherein the remote base unit is
adapted to supply a pressure control signal to the reduced-pressure
source.
9. The system of claim 5, wherein the reduced-pressure source and
the remote base unit comprise an integrated treatment unit.
10. The system of claim 5, wherein the second processor is adapted
to receive an ID signal and to determine if the ID signal
represents an approved dressing.
11. The system of claim 5, wherein the reduced-pressure source
comprises a micropump adjacent to the distribution manifold.
12. The system of claim 5, wherein the first, wireless,
reduced-pressure dressing does not include a battery.
13. The system of claim 5, wherein the first, wireless,
reduced-pressure dressing is adjacent to a first tissue site, and
further comprising a second, wireless, reduced-pressure dressing
adjacent to a second tissue site.
14. A wireless, reduced-pressure dressing for treating a tissue
site with reduced pressure, the wireless, reduced-pressure dressing
comprising: a distribution manifold for placing adjacent to the
tissue site and for providing reduced pressure to the tissue site;
a sealing member covering at least a portion of the distribution
manifold; a first processor; a RFID antenna coupled to the first
processor; and a first sensor coupled to the first processor,
wherein the first sensor comprises a pressure sensor.
15. The wireless, reduced-pressure dressing of claim 14, further
comprising a second sensor coupled to the first processor, wherein
the second sensor is selected from the group: temperature sensor,
pH sensor, a humidity sensor, a volatile organic compound sensor, a
blood sensor, and a growth factor sensor.
16. (canceled)
17. (canceled)
18. (canceled)
19. (canceled)
20. (canceled)
21. (canceled)
22. (canceled)
23. (canceled)
24. (canceled)
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
29. A wireless, reduced-pressure dressing for use on a tissue site,
the wireless, reduced-pressure dressing comprising: a sealing
member for covering at least a portion of the tissue site; a first
processor; a RFID antenna coupled to the first processor; and a
first sensor coupled to the first processor.
30. The wireless, reduced-pressure dressing of claim 29, wherein
the first sensor comprises a pressure sensor.
31. The wireless, reduced-pressure dressing of claim 29, further
comprising a second sensor coupled to the first processor, wherein
the second sensor is selected from the group: temperature sensor,
pH sensor, a humidity sensor, a volatile organic compound sensor, a
blood sensor, and a growth factor sensor.
32. The wireless, reduced-pressure dressing of claim 29, further
comprising a distribution manifold.
33. The wireless, reduced-pressure dressing of claim 32, further
comprising a reduced-pressure source fluidly coupled to the
reduced-pressure dressing.
Description
RELATED APPLICATION
[0001] The present invention claims the benefit, under 35 USC
.sctn.119(e), of the filing of U.S. Provisional Patent Application
Ser. No. 61/407,194, entitled "System and Methods For Electrically
Detecting The Presence of Exudate In Reduced-Pressure Dressings,"
filed 27 Oct. 2010, which is incorporated herein by reference for
all purposes [VAC.0975PRO1]; U.S. Provisional Patent Application
Ser. No. 61/418,730, entitled "Systems and Methods for Electrically
Detecting the Presence of Exudate in Dressings," filed 1 Dec. 2010,
which is incorporated herein by reference for all purposes
[VAC.0975PRO2]; U.S. Provisional Patent Application Ser. No.
61/445,383, entitled "Interactive, Wireless Reduced-Pressure
Dressings, Methods, and Systems," filed 22 Feb. 2011, which is
incorporated herein by reference for all purposes [VAC.0999PRO];
and U.S. Provisional Patent Application Ser. No. 61/445,338,
entitled "Reduced-Pressure Systems, Dressings, and Methods
Employing a Wireless Pump," filed 22 Feb. 2011, which is
incorporated herein by reference for all purposes
[VAC.1000PRO].
FIELD
[0002] The present disclosure relates generally to medical
treatment systems and, more particularly, but not by way of
limitation, to interactive, wireless dressings, methods, and
systems for use with reduced pressure.
BACKGROUND
[0003] Clinical studies and practice have shown that providing a
reduced pressure in proximity to a tissue site augments and
accelerates the growth of new tissue at the tissue site. The
applications of this phenomenon are numerous, but application of
reduced pressure has been particularly successful in treating
wounds. This treatment (frequently referred to in the medical
community as "negative pressure wound therapy," "reduced pressure
therapy," or "vacuum therapy") provides a number of benefits, which
may include faster healing and increased formulation of granulation
tissue. Typically, when applied to open wounds, reduced pressure is
applied to tissue through a porous pad or other manifold device.
The porous pad distributes reduced pressure to the tissue and
channels fluids that are drawn from the tissue. At times, a patient
may have a large wound requiring treatment at numerous sites or has
a plurality of tissue sites requiring treatment. At times, reduced
pressure may also be used within a body cavity to remove fluids
among other things.
SUMMARY
[0004] According to an illustrative embodiment, a system for
treating at least one tissue site with reduced pressure includes a
first, wireless, reduced-pressure dressing for disposing proximate
to the tissue site. The first, wireless, reduced-pressure dressing
includes a distribution manifold, a drape covering at least a
portion of the distribution manifold, a Radio Frequency
Identification (RFID) antenna, a first processor coupled to the
RFID antenna, and a first sensor coupled to the first processor.
The system also includes a remote base unit and a reduced-pressure
source. The reduced-pressure source is fluidly coupled to the
distribution manifold. The remote base unit includes a RFID antenna
and a second processor.
[0005] According to another illustrative embodiment, a wireless,
reduced-pressure dressing for treating a tissue site with reduced
pressure includes a distribution manifold for placing adjacent to
the tissue site and for providing reduced pressure to the tissue
site, a drape covering at least a portion of the distribution
manifold, a first processor, a RFID antenna coupled to the first
processor, and a first sensor coupled to the first processor. The
first sensor may be a pressure sensor.
[0006] According to another illustrative embodiment, a method for
treating at least one tissue site with reduced pressure includes
the steps of disposing a first, wireless, reduced-pressure dressing
proximate to a first tissue site. The first, wireless,
reduced-pressure dressing includes a distribution manifold for
placing adjacent to the tissue site and for providing reduced
pressure to the tissue site, a drape covering at least a portion of
the distribution manifold, a first processor, a RFID antenna
coupled to the first processor, and a first sensor coupled to the
first processor. The first sensor is a pressure sensor. The method
further includes providing a remote base unit that has a RFID
reader, providing reduced pressure to the distribution manifold,
transmitting a pressure inquiry signal from the RFID reader to the
first, wireless, reduced-pressure dressing, and receiving a
pressure message signal from the first, wireless, reduced-pressure
dressing.
[0007] According to another illustrative embodiment, a method for
treating at least one tissue site with reduced pressure includes
the steps of disposing a first, wireless, reduced-pressure dressing
proximate to a first tissue site. The first, wireless,
reduced-pressure dressing includes a distribution manifold for
placing adjacent to the tissue site and for providing reduced
pressure to the tissue site, a drape covering at least a portion of
the distribution manifold, a first processor, a RFID antenna
coupled to the first processor, and a first sensor coupled to the
first processor. The first sensor may be a pressure sensor. The
method further includes providing a remote base unit having a RFID
reader. The remote base unit also includes a second processor
coupled to the RFID reader. The method further includes providing a
reduced-pressure source; transmitting an ID inquiry signal from the
remote base unit to the first, wireless, reduced-pressure dressing;
receiving the ID inquiry signal at the first, wireless,
reduced-pressure dressing and producing an ID message signal;
transmitting the ID message signal from the first, wireless,
reduced-pressure dressing to the remote base unit; receiving the ID
message signal at the remote base unit; determining if the ID
message signal is on an approved list; and activating the
reduced-pressure source to provide reduced pressure to the
distribution manifold if the ID message signal represents a
dressing that is on the approved list or indicating an error if the
ID message signal represents a dressing that is not on the approved
list.
[0008] According to another illustrative embodiment, a system for
treating at least one tissue site with reduced pressure includes a
first, wireless, reduced-pressure dressing for disposing proximate
to the tissue site. The first, wireless, reduced-pressure dressing
includes a distribution manifold, a drape covering at least a
portion of the distribution manifold, a reduced-pressure interface
for providing reduced pressure to the distribution manifold, a
first RFID antenna, a first processor coupled to the first RFID
antenna, a first sensor coupled to the first processor, and a
membrane. The membrane covers at least a portion of the
reduced-pressure interface and is initially in an occlusive state
that prevents or hinders fluid flow through the reduced-pressure
interface. The first, wireless, reduced-pressure dressing further
includes a dissolution element proximate to the membrane that is
adapted to change the membrane from the occlusive state to a
non-occlusive state. When changed to the non-occlusive state, the
membrane allows flow through reduced-pressure interface. The system
further includes a remote base unit having a RFID reader and a
second processor. The system also includes a reduced-pressure
source fluidly coupled to the distribution manifold. The second
processor is configured to transmit an activation signal with the
RFID reader to the first, wireless, reduced-pressure dressing and
wherein in response to the activation signal, the first processor
is configured to deliver power to the dissolution element to change
the membrane from the occlusive state to the non-occlusive state.
The second processor is configured to transmit an ID inquiry signal
with the RFID reader to the first, wireless, reduced-pressure
dressing, and wherein, in response to the ID inquiry signal, the
first processor is configured to transmit an ID message signal with
the first RFID antenna. The second processor is adapted to receive
the ID message signal via the RFID reader and to determine if the
ID message signal represents an acceptable dressing.
[0009] According to another illustrative embodiment, a system for
treating a tissue site with reduced pressure includes a wireless,
reduced-pressure dressing that includes a distribution manifold, a
drape covering the distribution manifold, and a reduced-pressure
interface. The system also includes a WISP device associated with
the wireless, reduced-pressure dressing, a remote base unit
comprising a RFID reader, and a reduced-pressure source fluidly
coupled to the wireless, reduced-pressure dressing.
[0010] According to another illustrative embodiment, a method for
treating at least one tissue site with reduced pressure includes
disposing a first, wireless, reduced-pressure dressing proximate to
a first tissue site. The first, wireless, reduced-pressure dressing
includes a distribution manifold for placing adjacent to the tissue
site and for providing reduced pressure to the tissue site, a drape
covering at least a portion of the distribution manifold, a
reduced-pressure interface, and a membrane. The membrane is
initially occlusive and covers at least a portion of the
reduced-pressure interface. The membrane is adapted to prevent
fluid flow through the reduced-pressure interface when in the
occlusive state. The first, wireless, reduced-pressure dressing
also includes a first processor, a RFID antenna coupled to the
first processor, a first sensor coupled to the first processor, and
a dissolution element proximate to the membrane that is operable,
when activated, to change the membrane from an occlusive state to a
non-occlusive state. The first sensor is a pressure sensor. The
dissolution element is coupled to the first processor. The method
further includes providing a remote base unit having a RFID reader.
The remote base unit includes a second processor. The method also
involves providing a reduced-pressure source fluidly coupled to the
reduced-pressure interface, transmitting an activation signal from
the remote base unit to the first, wireless, reduced-pressure
dressing, whereupon the first processor activates the dissolution
element to change the membrane to the non-occlusive state, and
providing reduced pressure from the reduced-pressure source to the
reduced-pressure interface.
[0011] Other features and advantages of the illustrative
embodiments will become apparent with reference to the drawings and
detailed description that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic diagram, with a portion shown in cross
section, of an illustrative embodiment of a system for treating at
least one tissue site with reduced pressure;
[0013] FIG. 2 is a schematic top view of a first, wireless,
reduced-pressure dressing of the system of FIG. 1;
[0014] FIG. 3 is a schematic diagram, with a portion shown in cross
section, of an illustrative embodiment of a system for treating at
least one tissue site with reduced pressure;
[0015] FIG. 4 is a schematic top view of an illustrative embodiment
of a first, wireless, reduced-pressure dressing;
[0016] FIG. 5 is a schematic diagram, with a portion shown in cross
section, of an illustrative embodiment of a system for treating at
least one tissue site with reduced pressure; and
[0017] FIGS. 6A and 6B are an illustrative embodiment of a process
flow chart for a system for treating at least one tissue site with
reduced pressure.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0018] In the following detailed description of the illustrative
embodiments, reference is made to the accompanying drawings that
form a part hereof. These illustrative embodiments are described in
sufficient detail to enable those skilled in the art to practice
the invention, and it is understood that other embodiments may be
utilized and that logical structural, mechanical, electrical, and
chemical changes may be made without departing from the spirit or
scope of the invention. To avoid detail not necessary to enable
those skilled in the art to practice the embodiments described
herein, the description may omit certain information known to those
skilled in the art. The following detailed description is not to be
taken in a limiting sense, and the scope of the illustrative
embodiments are defined only by the appended claims.
[0019] In treating a tissue site or sites on a patient with reduced
pressure, it is typically desirable to maintain the reduced
pressure in a therapeutic range. While the amount and nature of
reduced pressure applied to a tissue site will typically vary
according to the application, the reduced pressure will typically
be between -5 mm Hg and -500 mm Hg and more typically -75 mm Hg and
-300 mm Hg, and more typically still, -100 to -200 mm Hg. In some
instances, failure to provide reduced pressure to a tissue site can
lead to serious consequences. Accordingly, it may be desirable to
monitor the pressure at each tissue site undergoing treatment.
[0020] To accommodate multiple tissue sites, e.g., multiple wounds,
multiple conduits may be used to deliver reduced pressure. For
example, a single reduced-pressure source may be used with the
multiple conduits branched off of one conduit. Currently, pressure
monitoring is typically located in existing reduced-pressure
sources and only one conduit communicates pressure to the
reduced-pressure source. If only one conduit, which is associated
with one tissue site, is monitored, as is the case when monitoring
is done at the reduced-pressure source alone, pressures at other
tissue sites are unmonitored. With at least some of the
illustrative embodiments herein, each tissue site of the plurality
of tissue sites is monitored so that issues with reduced pressure
delivery may be identified and addressed. Moreover, other
parameters may be monitored to track progress or identify issues
with healing of the tissue sites.
[0021] Reduced pressure may be used to treat open wounds to promote
the granulation tissue. Reduced pressure may also be applied to a
tissue site internal to a patient to remove fluids. For example,
reduced pressure may be used to remove ascites from a patient's
abdomen. In such situations it may be desirable to know the
pressure at the internal location as well as other parameters.
Reduced pressure may be used for other applications to promote
healing. The illustrative embodiments herein may be operable to
perform these tasks.
[0022] The illustrative embodiments herein involve using Radio
Frequency Identification (RFID) technology, including enhanced RFID
technology, to wirelessly transmit and receive sensing information
from a reduced-pressure dressing. RFID uses a RFID tag or label
that is on a target and a RFID reader that energizes and reads a
signal from the RFID tag. Most RFID tags include an integrated
circuit for storing and processing information, a modulator, and
demodulator. To enhance the RFID tag, a microcontroller (or
processor) and sensor are incorporated that allow sensing and
optional computational functions to occur. RFID tags can be passive
tags, active RFID tags, and battery-assisted passive tags.
Generally, passive tags use no battery and do not transmit
information unless they are energized by a RFID reader. Active tags
have an on-board battery and can transmit autonomously (i.e.,
without being energized by a RFID reader). Battery-assisted passive
tags typically have a small battery on-board that is activated in
the presence of a RFID reader.
[0023] In one illustrative embodiment, the enhanced RFID technology
is a Wireless Identification and Sensing Platform (WISP) device.
WISPs involve powering and reading a WISP device, analogous to a
RFID tag (or label), with a RFID reader. The WISP device harvests
the power from the RFID reader's emitted radio signals and performs
sensing functions (and optionally performs computational
functions). The WISP device transmits a radio signal with
information to the RFID reader. The WISP device receives power from
the RFID reader. The WISP device has a tag or antenna that harvests
energy and a microcontroller (or processor) that can perform a
variety of tasks, such as sampling sensors. The WISP device reports
data to the RFID reader. In one illustrative embodiment, the WISP
device includes an integrated circuit with power harvesting
circuitry, demodulator, modulator, microcontroller, sensors, and
may include one or more capacitors for storing energy. A form of
WISP technology has been developed by Intel Research Seattle
(www.seattle.intel-research.net/wisp/).
[0024] Referring now to the drawings and initially to FIGS. 1-3, a
system 100 for treating at least one tissue site 102, e.g., a wound
site 104, with reduced pressure is presented. The illustrative
wound site 104 is shown through epidermis 108 and into the
subcutaneous tissue 110 of a patient 106. The tissue site 102 may
be the bodily tissue of any human, animal, or other organism,
including bone tissue, adipose tissue, muscle tissue, dermal
tissue, vascular tissue, connective tissue, cartilage, tendons,
ligaments, or any other tissue. Treatment of tissue site 102 may
include removal of fluids, e.g., exudate or ascites. Unless
otherwise indicated, as used throughout this document, "or" does
not require mutual exclusivity. Treatment of a tissue site 102 may
include removal of fluids, e.g., exudate or ascites.
[0025] The system 100 may be used to treat the tissue site 102 with
reduced pressure to help form granulation tissue (reduced pressure
therapy), to remove fluids with out promoting tissue growth, or any
other purpose for which reduced pressure is helpful. The system 100
includes a first, wireless, reduced-pressure dressing 112 for
disposing proximate to the tissue site 102, a remote base unit 114,
and a reduced-pressure source 116.
[0026] The first, wireless, reduced-pressure dressing 112 may
include a distribution manifold 118, a sealing member 120 (or
drape) covering at least a portion of the distribution manifold
118, a first RFID antenna 122, a first processor 124 coupled to the
first RFID antenna 122, and a first sensor 126 coupled to the first
processor 124. The first processor 124 and first sensor 126 may be
associated with a board 127 or housing.
[0027] The sealing member 120 creates a fluid seal over the
distribution manifold 118 on a portion of a patient's epidermis 108
or may help provide a fluid seal at other locations. "Fluid seal,"
or "seal," means a seal adequate to maintain reduced pressure at a
desired tissue site given the particular reduced-pressure source or
subsystem involved. The sealing member 120, may include an
attachment device 128. The sealing member 120 creates a sealed
space 130 in which the distribution manifold 118 may be positioned.
A reduced-pressure interface 132 may be placed through an aperture
in the sealing member 120 to provide reduced pressure into the
sealed space 130 and in particular to the distribution manifold
118. Other wireless reduced-pressure dressings may be used as part
of the system 100 to accommodate multiple tissue sites, and the
additional wireless reduced-pressure dressings may be analogous to
the first, wireless, reduced-pressure dressing 112.
[0028] With respect to the distribution manifold 118, the term
"manifold" as used herein generally refers to a substance or
structure that is provided to assist in applying reduced pressure
to, delivering fluids to, or removing fluids from a tissue site,
e.g., tissue site 102. The distribution manifold 118 typically
includes a plurality of flow channels or pathways that distribute
fluids provided to and removed from the tissue site 102 around the
distribution manifold 118. In one illustrative embodiment, the flow
channels or pathways are interconnected to improve distribution of
fluids provided or removed from the tissue site 102. The
distribution manifold 118 may also be a biocompatible material that
is capable of being placed in contact with the tissue site 102 and
distributing reduced pressure to the tissue site 102. Examples of
manifolds 118 may include, without limitation, devices that have
structural elements arranged to form flow channels, such as, for
example, cellular foam, open-cell foam, porous tissue collections,
liquids, gels, and foams that include, or cure to include, flow
channels. The examples are not mutually exclusive.
[0029] The distribution manifold 118 may be porous and may be made
from foam, gauze, felted mat, or any other material suited to a
particular biological application. In one embodiment, the
distribution manifold 118 is a porous foam and includes a plurality
of interconnected cells or pores that act as flow channels. The
porous foam may be a polyurethane, open-cell, reticulated foam such
as GranuFoam.RTM. material manufactured by Kinetic Concepts,
Incorporated of San Antonio, Tex. Other embodiments may include
"closed cells." In some situations, the distribution manifold 118
may also be used to distribute fluids such as medications,
antibacterials, growth factors, and various solutions to the tissue
site 102. Other layers may be included in or on the distribution
manifold 118 such as absorptive materials, wicking materials,
hydrophobic materials, and hydrophilic materials.
[0030] In one illustrative embodiment, the distribution manifold
118, or portions of the distribution manifold 118, may be
constructed from bioresorbable materials that may remain in a
patient's body following use of the wireless, reduced-pressure
dressing 112. Suitable bioresorbable materials may include, without
limitation, a polymeric blend of polylactic acid (PLA) and
polyglycolic acid (PGA). The polymeric blend may also include
without limitation polycarbonates, polyfumarates, and
capralactones. The distribution manifold 118 may further serve as a
scaffold for new cell growth, or a scaffold material may be used in
conjunction with the distribution manifold 118 to promote cell
growth. A scaffold is a substance or structure used to enhance or
promote the growth of cells or formation of tissue, such as a
three-dimensional porous structure that provides a template for
cell growth. Illustrative examples of scaffold materials include
calcium phosphate, collagen, PLA/PGA, coral hydroxy apatites,
carbonates, or processed allograft materials.
[0031] The sealing member 120 may be any material that provides a
fluid seal. The sealing member 120 may, for example, be an
impermeable or semi-permeable, elastomeric material. "Elastomeric"
means having the properties of an elastomer. It generally refers to
a polymeric material that has rubber-like properties. More
specifically, most elastomers have ultimate elongations greater
than 100% and a significant amount of resilience. The resilience of
a material refers to the material's ability to recover from an
elastic deformation. Examples of elastomers may include, but are
not limited to, natural rubbers, polyisoprene, styrene butadiene
rubber, chloroprene rubber, polybutadiene, nitrile rubber, butyl
rubber, ethylene propylene rubber, ethylene propylene diene
monomer, chlorosulfonated polyethylene, polysulfide rubber,
polyurethane (PU), EVA film, co-polyester, and silicones.
Additional, specific examples of sealing member materials include a
silicone drape, 3M Tegaderm.RTM. drape, polyurethane (PU) drape
such as one available from Avery Dennison Corporation of Pasadena,
Calif.
[0032] The attachment device 128 may be used to maintain the
sealing member 120 against the patient's epidermis 108 or another
layer, such as a gasket or additional sealing member, or another
location. The attachment device 128 may take numerous forms. For
example, the attachment device 128 may be a medically acceptable,
pressure-sensitive adhesive that extends about a periphery, a
portion, or the entire sealing member 120.
[0033] The first, wireless, reduced-pressure dressing 112 provides
reduced pressure to one or more tissue sites 102. As used herein,
"reduced pressure" generally refers to a pressure less than the
ambient pressure at a tissue site that is being subjected to
treatment. In most cases, this reduced pressure will be less than
the atmospheric pressure at which the patient is located.
Alternatively, the reduced pressure may be less than a hydrostatic
pressure at the tissue site. Reduced pressure may initially
generate fluid flow in the distribution manifold 118 and proximate
the tissue site 102. As the hydrostatic pressure around the tissue
site 102 approaches the desired reduced pressure, the flow may
subside, and the reduced pressure may be maintained. Unless
otherwise indicated, values of pressure stated herein are gauge
pressures. Absolute pressure is referenced at times. The reduced
pressure delivered may be constant or varied (patterned or random)
and may be delivered continuously or intermittently. Although the
terms "vacuum" and "negative pressure" may be used to describe the
pressure applied to the tissue site, the actual pressure applied to
the tissue site may be more than the pressure normally associated
with a complete vacuum. Consistent with the use herein, an increase
in reduced pressure or vacuum pressure typically refers to a
relative reduction in absolute pressure.
[0034] The reduced-pressure interface 132 may be a structure or
means for fluidly coupling a reduced-pressure delivery conduit 134
to the distribution manifold 118. The reduced-pressure interface
132 may be a molded structure, a medical conduit (e.g., a portion
of reduced-pressure delivery conduit 134) applied to the
distribution manifold 118, or other device for coupling. As
discussed in connection with FIG. 4, a membrane, when in an
occlusive state, may prevent or hinder flow of fluid through the
reduced-pressure interface 132.
[0035] The reduced-pressure source 116 provides reduced pressure.
The reduced-pressure source 116 may be any device or source for
supplying a reduced pressure, such as a vacuum pump 136, wall
suction, micro-pump, or other source. As an aspect of the
reduced-pressure source 116 or as a separate member, a canister 138
may be included to receive and retain fluids 139. The remote base
unit 114 may be electrically coupled by coupling 140, e.g., wire or
wireless signal, to the reduced-pressure source 116 to provide a
pressure control signal to control the delivery of reduced pressure
to the first, wireless, reduced-pressure dressing 112 as will be
discussed further below. The reduced-pressure source 116 and the
remote base unit 114 may be an integrated unit in some embodiments.
"Remote" as used in the context of "remote base unit" typically
means displaced from a wireless, reduced-pressure dressing by a
distance greater than several millimeters and may include a base
unit immediately adjacent to a wireless, reduced-pressure dressing
but not electrically coupled.
[0036] The first sensor 126 may be a pressure sensor and may be
coupled to the first processor 124. The first processor 124 is
coupled to, or in communication with, the first RFID antenna 122.
The first sensor 126 may thus develop a signal indicative of
pressure experienced at a desired site in or on the first,
wireless, reduced-pressure dressing 112 and that signal may be
referred to as a pressure message signal. In other embodiments, the
first sensor 126 may be another type of sensor. For example, the
first sensor may be one of the following: a pressure sensor,
temperature sensor, pH sensor, humidity sensor, Volatile Organic
Compounds (VOC) sensor, blood sensor, or growth factors sensor. The
reduced-pressure interface 132 may include one or more pressure
conduits or channels 144 to provide reduced pressure for sampling
purposes to the first sensor 126.
[0037] A second sensor 142 may also be included and coupled to the
first processor 124. The second sensor 142 may be any type of
sensor such as those previously mentioned for the first sensor 126.
It will be appreciated that the first RFID antenna 122, first
processor 124, and first sensor 126 may comprise a Wireless
Identification and Sensing Platform (WISP) device. The first sensor
126, second sensor 142, or any other sensors may be located at any
location in the first, wireless, reduced-pressure dressing 112. In
one illustrative embodiment, the first sensor 126 may be adjacent
to the distribution manifold 118. In another illustrative
embodiment, the first sensor 126 may be at a remote portion of the
sealing member 120. In one illustrative embodiment, the sensors,
e.g., the first sensor 126, may be laminated to the sealing member
120 or otherwise attached to a portion of the sealing member 120
and may sample pressure in the sealed space 130. While two sensors
126, 142 have been mentioned, it should be understood that
additional sensors could be provided if desired.
[0038] In one illustrative embodiment, a battery is not associated,
with the first, wireless, reduced-pressure dressing 112. In other
words, the first, wireless, reduced-pressure dressing 112 is
passive. In such an embodiment, all the necessary energy for the
first processor 124 and first sensor 126 (and any additional,
optional sensors, e.g., second sensor 142) is harvested from
signals received by the first RFID antenna 122 from the remote base
unit 114. In other embodiments, a battery may be included to
provide the necessary power. With the power from the battery, the
first, wireless, reduced-pressure dressing 112 may transmit signals
independent of any signal from the remote base unit 114. In another
illustrative embodiment, a battery may be included to provide a
portion of the necessary power.
[0039] The remote base unit 114 may include a board or other
structure 115 that includes RFID reader 146 and a second processor
148. The remote base unit 114 may also include a first display 152,
e.g., a pressure indicator 154. The first display 152 or indicator
is for displaying a quantity measured by the first sensor 126 or an
indication of adequate pressure. Similarly, additional displays or
indicators may be included, e.g., a temperature display 156. One
display may be used for displaying multiple items, e.g., the data
from multiple sensors. A control panel 158, such as a push-button
panel or graphical user interface, may be included to receive input
from a user. The second processor 148 may be coupled by coupling
140 to the reduced-pressure source 116 to provide a control signal.
The control signal allows for automated adjustments to the pressure
at the tissue site 102 by controlling the pressure supplied by the
reduced-pressure source 116.
[0040] The RFID reader 146 may be a transceiver for transmitting to
and receiving signals from the first RFID antenna 122. If not
already converted, the RFID reader 146 may convert received signals
to digital format and provide the signals to the second processor
148. The remote base unit 114 may read signals as close as several
millimeters away or as far as 30 feet or more away or any distance
between, e.g., 5, 10, or 20 feet. The remote base unit 114 may poll
as often as desired, e.g., every 1/2 second, every second, every
hour, or any other time interval.
[0041] The second processor 148 includes memory and instructions
necessary to perform various desired steps. For example, a pairing
protocol may be executed. In the pairing protocol, the second
processor 148 with the RFID reader 146 transmits an ID inquiry
signal to the first, wireless, reduced-pressure dressing 112 to
inquire about the identification of the first, wireless,
reduced-pressure dressing 112. In response, the first processor 124
transmits an ID message signal. If the first, wireless,
reduced-pressure dressing 112 is not suitable for use with the
remote base unit 114 as determined by comparing the ID message with
an approved list or by information contained in the ID message
signal itself, the remote base unit 114 will not proceed with
executing instructions as part of therapy. This protocol should
safeguard against using a dressing that is not approved and which
may underperform with the remote base unit 114.
[0042] As an illustrative example, the second processor 148, RFID
reader 146, first RFID antenna 122, and first processor 124 may be
configured to perform the following steps: transmitting an ID
inquiry signal from the remote base unit 114 to the first,
wireless, reduced-pressure dressing 112; receiving the ID inquiry
signal at the first, wireless, reduced-pressure dressing 112 and
producing an ID message signal; transmitting the ID message signal
from the first, wireless, reduced-pressure dressing 112 to the
remote base unit 114; receiving the ID message signal at the remote
base unit 114; determining if the ID message signal represents a
dressing on an approved list; and activating the reduced-pressure
source 116 to provide reduced pressure to the distribution manifold
118 if the ID message signal represents a dressing that is on the
approved list (or otherwise acceptable) or indicating an error if
the ID message signal represents a dressing that is not on the
approved list.
[0043] Referring now primarily to FIG. 4, another illustrative
embodiment of a first, wireless, reduced-pressure dressing 112 is
presented. The first, wireless, reduced-pressure dressing 112 is
analogous to the first, wireless, reduced-pressure dressing 112 of
FIGS. 1-3 in most respects. A sealing member 120, or film, covers
the first RFID antenna 122, first processor 124, and first sensor
126. In this embodiment, a reduced-pressure interface (not shown
but analogous to reduced-pressure interface 132 of FIG. 1) may be
coupled over an aperture 121 in the sealing member 120 to allow
fluid communication, but initially a membrane 160 prevents or
hinders flow through the aperture 121.
[0044] The membrane 160 may have an occlusive state and a
non-occlusive state. The membrane 160 may be in the occlusive state
when the membrane 160 is an integral layer and may be non-occlusive
when one or more apertures are created in the membrane 160 that
allow fluid flow through the membrane. When initially over aperture
121 in the occlusive state, flow through the aperture 121 is
prevented (or substantially hindered), but when the membrane 160 is
changed to the non-occlusive state, flow through the membrane 160
and, thus, through the aperture 121 may occur. The membrane 160 may
move from the occlusive state to the non-occlusive state in
response to an activating event, e.g., the application heat, light,
ultrasound, a chemical, or other activating agent. For example, in
one illustrative embodiment, a dissolution element 162 is disposed
proximate to the membrane 160 and is adapted to (or operable to)
change the membrane 160 from an occlusive state to a non-occlusive
state. The dissolution element 162 may be activated by the first
processor 124 to produce the activating event. In other
embodiments, the dissolution element 162 may be activated by the
second processor 148 or an external stimulus.
[0045] The dissolution element 162 may be, for example and not by
way of limitation, an electrically resistive heating element. Power
may be supplied from the first processor 124 to the dissolution
element 162 to sufficiently activate the electrically resistive
heating element to melt, dissolve or otherwise create an aperture
in the membrane 160. In another illustrative embodiment, the
dissolution element 162 is an ultrasonic device that creates an
aperture in membrane 160 when activated. In another illustrative
embodiment, the dissolution element 162 is a chemical distribution
device that upon receiving a signal from the first processor 124
releases an agent that causes the membrane 160 to dissolve, at
least in part, to create an aperture 121. In still another
illustrative embodiment, the dissolution element 162 is a light
with a first wavelength and the membrane 160 reacts to the light
with the first wavelength and dissolves at least a portion to
create an aperture.
[0046] The membrane 160 may be made from numerous materials
depending on the activation device used as the dissolution element
162. For example, the membrane 160 may comprise a semi-crystalline
thermoplastic film, such as LDPE, HDPE, PP, PA, having a thickness
in the range 15-100 .mu.m. The exact thickness of the membrane 160
depends on the material selected and the level of reduced pressure
that the membrane 160 will be required to resist. The temperature
required to rupture the membrane 160 should be approaching or at
the melting point of the polymer chosen. If heated whilst the
membrane 160 is under strain from applied negative pressure, the
temperature required to breakdown or dissolve the membrane 160 may
be reduced.
[0047] The dissolution element 162 may be a component laminated to
the membrane 160 during the manufacture of the membrane 160 or
attached later in production. The dissolution element 162 may be a
conductive component that is molded into the membrane 160 or added
to the membrane 160 so that the membrane 160 itself is conductive.
The conductive material may be metallic or one of the other
materials that are commonly used to provide conductivity to
polymers. Although the temperature required to melt some of the
membrane or film materials mentioned may be greater than
100.degree. C., the dissolution element 162 is separated from the
patient sufficiently to avoid injury or other potential
complications. Moreover, the membrane 160 may be extremely thin
such that very little energy is required to form an aperture
through the membrane 160.
[0048] Referring now primarily to FIGS. 1-4, if the first,
wireless, reduced-pressure dressing 112 includes the membrane 160
and dissolution element 162, an initial activation may be carried
out by the remote base unit 114 and first processor 124. As an
illustrative example, the remote base unit 114 may transmit an
activation signal from the remote base unit 114 to the first,
wireless, reduced-pressure dressing 112. Upon receiving the
activation signal, the first processor 124 activates the
dissolution element 162 to change the membrane 160 to the
non-occlusive state such as by creating an aperture over the
aperture 121. Reduced pressure from the reduced-pressure source 116
may then be delivered through the reduced-pressure interface 132
and the aperture 121 to the distribution manifold 118. If a user is
attempting to use a remote base unit that is not designed for use
with the first, wireless, reduced-pressure dressing 112, the remote
base unit will not respond to the activation signal and will not
change the membrane 160 from the occlusive state to the
non-occlusive state. Accordingly, the first, wireless,
reduced-pressure dressing 112 would be unable to establish fluid
flow through the membrane 160 to the distribution manifold 118.
[0049] According to one illustrative embodiment, in operation, the
first, wireless, reduced-pressure dressing 112 is disposed
proximate to the tissue site 102. The distribution manifold 118 is
placed adjacent to the tissue site 102. The sealing member 120 is
releaseably attached to the epidermis 108 with the attachment
device 128. The reduced-pressure delivery conduit 134 is fluidly
coupled between the reduced-pressure interface 132 and the
reduced-pressure source 116. The remote base unit 114 may be
activated by the user with the control panel 158.
[0050] The remote base unit 114 may initially transmit an
activation signal to the first, wireless, reduced-pressure dressing
112 to cause the membrane 160 to change from an occlusive state to
a non-occlusive state as previously described. The remote base unit
114 may then transmit an ID inquiry signal to identify the dressing
type. The first, wireless, reduced-pressure dressing 112 receives
the ID inquiry signal and, in response, transmits an ID message
signal indicative of the dressing type. The second processor 148
may receive the ID message signal and look up the ID message signal
or otherwise determine if the dressing represented by the ID
message signal is acceptable. If the dressing is acceptable, the
second processor 148 may cause a control signal to be sent, e.g.,
by coupling 140, to the reduced-pressure source 116 to activate the
reduced-pressure source 116 and begin treatment with reduced
pressure. In another embodiment, the dressing type may be validated
before an activation signal is sent.
[0051] The remote base unit 114 may be configured to transmit a
pressure inquiry signal to the first, wireless, reduced-pressure
dressing 112. In response, the first, wireless, reduced-pressure
dressing 112 ascertains the pressure with the first sensor 126 and
transmits a pressure message signal to the remote base unit 114.
Based on the pressure message signal, the remote base unit 114
determines if the pressure is greater than a first target pressure
(on an absolute scale), and if so, continues operation of the
reduced-pressure source 116. But if the pressure message signal
indicates that the pressure is less than the first target pressure
(on absolute scale), the second processor 148 may send a control
signal stopping the reduced pressure source 116 from delivering
reduced pressure. Operation of the reduced-pressure source 116 may
be by manipulation of a valve or power to a vacuum pump or other
like techniques. The remote base unit 114 may interrogate the
first, wireless, reduced-pressure dressing 112 from time to time to
monitor the pressure. If the pressure becomes greater than the
first target pressure (on an absolute scale), the reduced-pressure
source 116 will again be activated by a control signal. Thus, a
feedback loop may be utilized.
[0052] If a patient has a plurality of tissue sites 102 requiring
treatment, a plurality of wireless, reduced-pressure dressings may
be used. For example, the first, wireless, reduced-pressure
dressing 112 may be placed at the first tissue site 102 and a
second, wireless, reduced-pressure dressing (not shown, but
analogous to the reduced-pressure dressing 112) may be placed at a
second tissue site. Because the signals include unique
identification information, the remote base unit 114 may
communicate with both the first, wireless, reduced-pressure
dressing 112 and the second, wireless, reduced-pressure dressing.
This arrangement allows monitoring and control of reduced pressure
at each of the plurality of tissue sites. Multiple remote base
units 114 may also be used. For example, each first processor 124
may include dynamic RAM that includes a register that is configured
when paired to a particular remote base unit 114. Thus, the first,
wireless, reduced-pressure dressing 112 is able to distinguish
which remote base unit 114 has been assigned. The first, wireless,
reduced-pressure dressing 112 may include a reset button that
transmits a reset signal to the first processor 124 to allow the
dressing and base association to be changed.
[0053] Referring now primarily to FIG. 5, another illustrative
embodiment of a system 100 for treating at least one tissue site
102 with reduced pressure is presented. The system 100 includes a
first, wireless, reduced-pressure dressing 112. The system 100 is
analogous in most respects to the system 100 of FIG. 1, except that
a reduced-pressure source 116 is a micro-pump 117, e.g., a
piezoelectric pump, and is adjacent to the distribution manifold
118. In addition, an absorbent layer 119 is also explicitly
included. As used throughout this document in connection with the
micro-pump 117, "adjacent" means next to, in the vicinity of, and
also includes in.
[0054] A dedicated battery 166 may be coupled to the micro-pump 117
to provide power to the micro-pump 117. A vent line 168 may be used
to allow the micro-pump 117 to vent or exhaust outside of the
first, wireless, reduced-pressure dressing 112. In this embodiment,
a first processor (analogous to first processor 124 of FIG. 3) that
is associated with a WISP or RFID device 170, may be instructed by
the remote base unit 114 to deliver a control signal to the
micro-pump 117 when necessary. In another illustrative embodiment,
the first processor may receive a pressure message signal
indicative of the pressure at the distribution manifold 118,
compare the pressure to a target pressure, and in response deliver
a control signal to the micro pump 117 to control the micro-pump
117 as needed. In another illustrative embodiment, the device 170
may harvest power to not only energize the first processor and
first sensor, but also the micro-pump 117. It should be noted that
a capacitor (not explicitly shown) may be included to help build
and retain a charge for powering devices in the first, wireless,
reduced-pressure dressing 112.
[0055] Referring now to FIGS. 3, 4, and 6, and primarily to FIG. 6,
a treatment process that may be executed with the system 100 is
presented. The process begins at 200. At step 202, the remote base
unit 114 transmits an activation signal to the first, wireless,
reduced pressure dressing 112. The first RFID antenna 122 receives
the activation signal. The activation signal energizes the first
processor 124. The first processor 124 activates the dissolution
element 162. The dissolution element 162 changes the membrane 160
from an occlusive state to a non-occlusive state that allows flow.
It should be appreciated that the need to change the membrane 160
to a non-occlusive state helps make sure that only appropriate
(approved) remote base units 114 are used with the first, wireless,
reduced-pressure dressing 112.
[0056] At step 204, the remote base unit 114 transmits an ID
inquiry signal to the first, wireless, reduced-pressure dressing
112. The first RFID antenna 122 receives the ID inquiry signal. The
ID inquiry signal energizes the first processor 124 and provides an
identification request to the first processor 124. In response, the
first processor 124 transmits an ID message signal from the first
RFID antenna 122 to the RFID reader 146 on the remote base unit
114. The remote base unit 114 waits for the ID message signal at
interrogatory 206.
[0057] At interrogatory 206, the second processor 148 waits a
predetermined time for the ID message signal. If the ID message
signal is not received during the predetermined time, the process
proceeds to step 208 where an error flag is posted and the process
ends at 210. The error flag may include posting a message for
display at control panel 158 or sounding an alarm or providing
other notification. If the ID message signal is received, the
process proceeds to interrogatory 212.
[0058] At interrogatory 212, inquiry is made as to whether the ID
message signal represents a dressing that is acceptable or
approved. To answer the inquiry, the second processor 148 compares
the dressing represented by the ID message signal with a list of
acceptable or approved dressings. If the dressing represented by
the ID message signal is on the list of acceptable or approved
dressings, the process continues to step 214 and if not the process
proceeds to step 208 and an error flag is posted and the process
ends at 210.
[0059] At step 214, a first chronograph, T1, is initiated to keep a
running cycle time. The process then proceeds to step 216. At step
216, the second processor 148 provides a control signal via
coupling 140 to the reduced-pressure source 116 to activate the
reduced-pressure source 116. Once the reduced-pressure source 116
is activated, reduced pressure flows to the first, wireless,
reduced-pressure dressing 112.
[0060] At step 218, the remote base unit 114 transmits a pressure
inquiry signal to the first, wireless, reduced-pressure dressing
112. The first RFID antenna 122 receives the pressure inquiry
signal. The pressure inquiry signal energizes the first processor
124 and first sensor 126. In response, the first processor 124
transmits a pressure message signal to the remote base unit 114.
The RFID reader 146 receives and delivers the pressure message
signal to the second processor 148. At interrogatory 220, the
second processor 148 then compares the pressure message signal,
which indicates the pressure substantially at the distribution
manifold 118 or other desired location, with a target pressure. If
the pressure message signal indicates a pressure that is greater
than the target pressure on an absolute scale, then more reduced
pressure is needed and the delivery of reduced pressure continues.
The process proceeds to interrogatory 222. On the other hand, if
the pressure message signal indicates a pressure that is less than
the target pressure on an absolute scale, then the process proceeds
to step 224.
[0061] At decision step 222, the second processor 148 compares the
elapsed time of the first chronograph, T1, with a maximum time,
T1max. If the maximum time has been exceeded, the process continues
to step 226. At step 226, the second processor 148 posts an error
flag and the process ends at 228. The error flag may include
sounding an alarm or displaying a message on the control panel 158
or otherwise notifying the user of a problem. If the maximum time
has not been exceeded, the process returns to step 218. The loop
(218, 220, 222, 218, . . . ) continues until the maximum time is
exceeded or a suitable reduced pressure is reached.
[0062] Once the pressure is suitable, the process proceeds to step
224 where the second processor 148 initiates a therapy chronograph
that keeps an elapsed time, T2, for therapy. Next, at step 230, the
second processor 148 initiates a cycle chronograph, T3. The process
then proceeds to interrogatory 232, wherein the elapsed therapy
time, T2, is compared to a maximum allowed value. If the elapsed
therapy time, T2, is greater than the maximum allowed value, then a
flag indicating that therapy is complete is given at step 234 and
the process ends 250. Otherwise, the process continues to step
236.
[0063] At step 236, the remote base unit 114 transmits a pressure
inquiry signal to the first, wireless, reduced-pressure dressing
112. The first RFID antenna 122 receives the pressure inquiry
signal. The pressure inquiry signal is then delivered to the first
processor 124. The pressure inquiry signal energizes the first
processor 124 and the first sensor 126. In response, the first
processor 124 develops a pressure message signal. The first
processor 124 and first RFID antenna 122 transmit the pressure
message signal to the remote base unit 114. The pressure message
signal is received and delivered to the second processor 148. At
interrogatory 238, the pressure at the distribution manifold 118
(or other desired location) as represented by the pressure message
signal is compared to a target value on an absolute scale. If the
pressure is greater than the target value, reduced pressure needs
to be applied (or continued), and the second processor 148
transmits (or continues) a control signal to the reduced-pressure
source 116 at step 240. If the pressure is less than the target
value, the process pauses at step 242 and continues to monitor
pressure by returning to step 230.
[0064] At interrogatory 244, the elapsed cycle time, T3, is
compared to a maximum value, T3max. If the elapsed cycle time T3 is
greater than the maximum value T3max, the system 100 is apparently
unable to adequately lower the pressure. Such a condition may occur
because of a leak. Accordingly, an error flag or alarm is initiated
at step 246 and the process ends 248. If the elapsed cycle time,
T3, is less than the maximum value, T3max, the cycle continues with
the process going to interrogatory 232.
[0065] The process presented in FIGS. 6A-6B is one illustrative
embodiment. Many embodiments are possible. Other process flows may
include analogous instructions for receiving temperature message
signals from the second sensor 142 or other data depending on the
sensor type. In another illustrative embodiment, the activation
step may follow the steps required to confirm an approved
dressing.
[0066] Since the pressure measurements are taken at the first,
wireless, reduced-pressure dressing 112 and wirelessly transmitted
to the remote base unit 114, the reduced-pressure delivery conduit
134 may be relatively smaller as a pressure sensing lumen is not
required as part of the reduced-pressure delivery conduit 134. In
other words, pressure is measured and the pressure signal is
transmitted to the remote base unit 114 without transmission
through a wire and without requiring sampling pressure to be
communicated through the reduced-pressure delivery conduit 134.
[0067] In another illustrative embodiment, the first, wireless,
reduced-pressure dressing may be a distribution manifold enclosed
by a drape that has been fenestrated or otherwise allows flow. This
illustrative embodiment is suitable for use in a body cavity that
is closed, such as placing one in an abdominal cavity and
monitoring pressure therein. In such an embodiment, the pressure
sensor or other sensors may be located anywhere in or on the
dressing and are operable to communicate with a remote base outside
of the body cavity. In one embodiment, the pressure sensor may be
located at peripheral edge of the dressing that is used in an
abdominal cavity. The peripheral edge is disposed near the
patient's paracolic gutter to monitor pressure and fluid
removal.
[0068] The RFID antenna and first processor may be adapted to
provide an identification message signal for other purposes than
those previously presented. For example, in addition to utilization
of the identification message signal to confirm proper pairing of a
dressing and base, the identification message signal may be used
for inventory purposes. A scanner with a RFID reader may be used to
scan a wireless, reduced-pressure dressing and receive the
identification message signal.
[0069] In another illustrative embodiment, a release pouch is
provided that contains a fluid. The release pouch may be formed as
part of a wireless, reduced-pressure dressing. The release pouch
may be formed, for example, by an additional membrane attached on a
patient-facing side of the sealing member. A dissolution element
analogous to dissolution element 162 may be associated with the
release pouch. The dissolution element allows the first processor
124 to selectively dissolve or open a portion of the release pouch
to release any contents of the pouch. Thus, the release pouch may
be used to retain medicines or other substances and a wireless
signal may be sent to the wireless, reduced-pressure dressing
causing release of the medicine. For example, if a sensor detects
bacterial colonization, a signal may be sent, opening the pouch and
releasing an anti-biotic, or if high blood content is detected, a
signal may be sent releasing a coagulent.
[0070] In some embodiments of the wireless, reduced-pressure
dressing, the RFID antenna may be remote from the first processor,
but electrically coupled to the first processor. For example, a
larger RFID antenna may be used on the patient near the tissue site
to be treated, and a coupling wire may extend from the RFID antenna
to the first processor or first sensor adjacent to or on the
distribution manifold.
[0071] Although the present invention and its advantages have been
disclosed in the context of certain illustrative, non-limiting
embodiments, it should be understood that various changes,
substitutions, permutations, and alterations can be made without
departing from the scope of the invention as defined by the
appended claims. It will be appreciated that any feature that is
described in connection to any one embodiment may also be
applicable to any other embodiment.
[0072] It will be understood that the benefits and advantages
described above may relate to one embodiment or may relate to
several embodiments. It will further be understood that reference
to "an" item refers to one or more of those items.
[0073] The steps of the methods described herein may be carried out
in any suitable order, or simultaneously where appropriate.
[0074] Where appropriate, aspects of any of the embodiments
described above may be combined with aspects of any of the other
embodiments described to form further examples having comparable or
different properties and addressing the same or different
problems.
[0075] It will be understood that the above description of
preferred embodiments is given by way of example only and that
various modifications may be made by those skilled in the art. The
above specification, examples and data provide a complete
description of the structure and use of exemplary embodiments of
the invention. Although various embodiments of the invention have
been described above with a certain degree of particularity, or
with reference to one or more individual embodiments, those skilled
in the art could make numerous alterations to the disclosed
embodiments without departing from the scope of the claims.
* * * * *