U.S. patent application number 13/543574 was filed with the patent office on 2012-11-01 for work of breathing display for a ventilation system.
This patent application is currently assigned to NELLCOR PURITAN BENNETT INCORPORATED. Invention is credited to Peter R. Doyle, Warren G. Sanborn.
Application Number | 20120277616 13/543574 |
Document ID | / |
Family ID | 38748385 |
Filed Date | 2012-11-01 |
United States Patent
Application |
20120277616 |
Kind Code |
A1 |
Sanborn; Warren G. ; et
al. |
November 1, 2012 |
WORK OF BREATHING DISPLAY FOR A VENTILATION SYSTEM
Abstract
A breathing support system is provided. The system may include a
breathing support device configured to deliver gas to a patient and
a display device associated with the breathing support device. The
display device may he configured to display a work of breathing
graphic indicating one or more work of breathing measures regarding
the patient's breathing.
Inventors: |
Sanborn; Warren G.;
(Escondido, CA) ; Doyle; Peter R.; (Vista,
CA) |
Assignee: |
NELLCOR PURITAN BENNETT
INCORPORATED
Pleasanton
CA
|
Family ID: |
38748385 |
Appl. No.: |
13/543574 |
Filed: |
July 6, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13117644 |
May 27, 2011 |
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13543574 |
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11408457 |
Apr 21, 2006 |
8021310 |
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13117644 |
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Current U.S.
Class: |
600/538 ;
128/204.23 |
Current CPC
Class: |
A61B 5/742 20130101;
A61M 2016/003 20130101; A61M 2205/502 20130101; A61B 5/08 20130101;
A61M 2016/1025 20130101; A61B 5/082 20130101; A61M 16/142 20140204;
A61M 2230/40 20130101; A61M 2205/3368 20130101; A61M 16/024
20170801; A61M 2016/0027 20130101; A61M 16/0003 20140204; A61B
5/743 20130101; A61M 16/0051 20130101; A61M 2205/505 20130101; A61M
2230/46 20130101; A61B 5/087 20130101 |
Class at
Publication: |
600/538 ;
128/204.23 |
International
Class: |
A61B 5/087 20060101
A61B005/087; A61M 16/00 20060101 A61M016/00 |
Claims
1.-37. (canceled)
38. A breathing support system, comprising: a breathing support
device configured to deliver gas to a patient; a software-generated
image representing a work of breathing bar in conjunction with a
ventilation application indicating one or more work of breathing
measures regarding the patient's breathing, wherein the one or more
work of breathing measures include an elastic work of breathing
component and a resistive work of breathing component; a
software-generated image representing an elastic work of breathing
indicator indicating a measure of the elastic work of breathing
component; a software-generated image representing a resistive work
of breathing indicator indicating a measure of the resistive work
of breathing component; and a display device associated with the
breathing support device, the display device configured to display
the software-generated images, wherein the software-generated image
representing the work of breathing graphic includes: a
software-generated image representing a scale; and one or more
software-generated images representing work of breathing indicators
that move relative to the software-generated image representing the
scale to indicate the one or more work of breathing measures.
39. The breathing support system of claim 38, wherein the
ventilation application is proportional assist ventilation.
40. The breathing support system of claim 38, wherein the
ventilation application changes pressure based on a parameter
monitored by at least one sensor.
41. The breathing support system of claim 40, wherein the parameter
is flow.
42. The breathing support system of claim 40, wherein the parameter
is volume.
43. The breathing support system of claim 38, wherein the work of
breathing measures for the work of breathing bar are calculated
based on inputs for at least one algorithm for the ventilation
application.
44. The breathing support system of claim 43, wherein the
ventilation application is proportional assist ventilation.
45. The breathing support system of claim 43, wherein the
ventilation application changes pressure based on a parameter
monitored by at least one sensor.
46. The breathing support system of claim 44, wherein the parameter
is flow.
47. The breathing support system of claim 44, wherein the parameter
is volume.
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to the field of
respiratory support, and more particularly to a graphical display
indicating work of breathing measures.
BACKGROUND
[0002] One indication of a patient's condition during respiration
support is the status of the patient's work of breathing (WOB).
Work of breathing may be defined as the work associated with
inflating the patient's lungs during a breathing cycle. During
respiration support, a ventilator provides at least a portion of
the total work of breathing for the patient. The total work of
breathing (WOB.sub.TOTAL) may generally be defined as the sum of
the work of breathing provided by the patient (WOB.sub.PATIENT) and
the work of breathing support provided by the ventilator
(WOB.sub.VENTILATOR).
[0003] The work of breathing provided by the patient
(WOB.sub.PATIENT) may be approximated as the sum of two components:
an elastic WOB component (WOB.sub.PATIENT-ELASTIC) and a resistive
WOB component (WOB.sub.PATIENT-RESISTIVE). The elastic WOB
component is generally defined as the work required to overcome the
elastance of the patient's respiratory system, while the resistive
component is generally defined as the work required to overcome the
airway resistance of the patient's respiratory system.
[0004] Elastance may generally be defined in terms of the elastic
properties of the lung and chest, or the forces associated with
expanding the lung. In particular, the degree of stiffness of the
lung-chest region may be referred to as the elastance of the
respiratory system. The elastance of the respiratory system may
also be discussed in terms of compliance, which may be defined as
the inverse of elastance. Generally, the easier it is to stretch
the lung-chest region.
[0005] Resistance forces, or the non-elastic forces at work in the
breathing cycle, are the forces associated with moving air through
a patient's airways. Lung resistance may be at least partially
defined by a patient's physiological conditions. For example,
patients suffering from asthma typically experience muscular
constriction of the bronchi. Such patients may also experience
swelling of the bronchial mucosa. The work required to achieve a
particular amount of air flow through the breathing passageways
generally increases in proportion to the severity of constriction.
In some ventilation systems, flow and pressure sensors are used to
compute estimates of the patient's resistance and compliance.
[0006] One or more WOB values, e.g., the total WOB, the patient's
WOB (WOB.sub.PATIENT), the ventilator's WOB (WOB.sub.VENTILATOR),
the elastic WOB component (WOB.sub.PATIENT-ELASTIC), and/or the
resistive WOB component (WOB.sub.PATIENT-RESISTIVE) may be
determined and/or monitored in various manners. For example, a
patient's WOB may be determined from either measured or estimated
values relating to the patient's respiratory physiology by applying
direct or indirect approaches and following established algorithms.
Measured values may be obtained more directly by invasive
procedures, e.g., procedures that require the installation of an
esophageal balloon. Such techniques are typically invasive and
require specialized skill. Thus, outside of the research setting it
may be undesirable to obtain WOB measures employing such invasive
means.
[0007] In a pressure assisted ventilation (PAV) system, the
patient's work of breathing (WOB.sub.PATIENT), the elastic WOB
component (WOB.sub.PATIENT-ELASTIC), and/or the resistive WOB
component (WOB.sub.PATIENT-RESISTIVE) may be estimated by inputting
measurements from various sensors into the breathing algorithms. In
PAV ventilation, the patient is supplied with continuous pressure
assistance throughout an inspiratory effort and in direct
proportion to the moment-to-moment inspiratory effort. Typically,
none of the instantaneous inspiratory pressure, the instantaneous
flow, or the resulting volume are set by the caregiver. Because the
PAV breathing algorithm harmoniously links the ventilator to the
patient, the patient effectively "drives" the ventilator. By
appropriately setting the value of the proportionality (% support)
control, the caregiver may effectively partition the total WOB
between the patient (WOB.sub.PATIENT) and the ventilator
(WOB.sub.VENTILATOR).
[0008] The values of the patient's lung-chest compliance and lung
resistance may be continuously estimated and inserted into the PAV
breathing algorithm in order for the algorithm to function
properly. These estimates may be made automatically by the
ventilator and fed back to the breathing algorithm as perhaps
better fits the needs of the patient in intensive care, whereas
manual techniques may be used to estimate the values for more
stable patients, e.g., in a home setting.
SUMMARY
[0009] In accordance with the present disclosure, systems and
methods for monitoring and/or displaying one or more work of
breathing measures are provided.
[0010] According to one embodiment, a breathing support system is
provided. The system may include a breathing support device
configured to deliver gas to a patient and a display device
associated with the breathing support device. The display device
may be configured to display a work of breathing graphic indicating
one or more work of breathing measures regarding the patient's
breathing.
[0011] According to another embodiment, a device for displaying
work of breathing information associated with a breathing support
system is provided. The device may include a work of breathing
calculation module configured to determine one or more work of
breathing measures regarding a patient's breathing, and a display
configured to present a work of breathing graphic indicating the
one or more determined work of breathing measures.
[0012] According to yet another embodiment, a method for displaying
a work of breathing graphic associated with a breathing support
system is provided. The method may include calculating one or more
work of breathing measures regarding a patient's breathing, and
displaying a work of breathing graphic indicating the one or more
calculated work of breathing measures.
[0013] According to yet another embodiment, a ventilation system
for assisting with a patient's breathing is provided. The system
may include gas delivery means for delivering gas to a patient, and
display means for displaying a work of breathing graphic that
indicates one or more work of breathing measures regarding the
patient's breathing.
[0014] According to yet another embodiment, a computer-readable
medium including computer-executable instructions for providing a
work of breathing graphic associated with breathing support for a
patient is provided. The computer-executable instructions may
include instructions for calculating one or more work of breathing
measures regarding a patient's breathing, and instructions for
displaying a work of breathing graphic indicating the one or more
calculated work of breathing measures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Some embodiments of the disclosure may be understood by
referring, in part, to the following description and the
accompanying drawings, in which like reference numbers refer to the
same or like parts, and wherein:
[0016] FIG. 1 illustrates a ventilation system for providing
ventilation support to a patient, including a ventilator configured
to display a work of breathing graphic, according to one embodiment
of the disclosure;
[0017] FIG. 2 illustrates a ventilation system for providing
ventilation support to a patient, including a ventilator and a
separate module for displaying a work of breathing graphic,
according to one embodiment of the disclosure;
[0018] FIG. 3 is a block diagram illustrating an example system for
determining and displaying work of breathing measures, according to
some embodiments;
[0019] FIG. 4 illustrates a first example graphic work of breathing
graphic, according to one embodiment of the disclosure;
[0020] FIG. 5 illustrates a second example graphic work of
breathing graphic, according to one embodiment of the
disclosure;
[0021] FIG. 6 illustrates a third example graphic work of breathing
graphic, according to another embodiment of the disclosure;
[0022] FIG. 7 illustrates a fourth example graphic work of
breathing graphic, according to another embodiment of the
disclosure;
[0023] FIG. 8 illustrates a fifth example graphic work of breathing
graphic, according to another embodiment of the disclosure; and
[0024] FIG. 9 illustrates a sixth example graphic work of breathing
graphic, according to another embodiment of the disclosure.
DETAILED DESCRIPTION
[0025] Selected embodiments of the disclosure may be understood by
reference, in part, to FIGS. 1-9, wherein like numbers refer to
same and like parts.
[0026] In general, the present disclosure describes generating
and/or displaying a work of breathing graphic (WOB graphic) for use
with a ventilator or other breath delivery or breathing support
system that may provide caregivers with various information
concerning work of breathing through an easily understood graphical
display. The WOB graphic may be used, e.g., for monitoring and/or
adjusting the amount of work of breathing contributed by the
patient and/or the amount contributed by the ventilator. For
example, the display may allow a caregiver to monitor a patient's
work of breathing in real time or substantially in real time. A
caregiver may use such information for various purposes, such as,
for example, to ensure that the patient's work of breathing is
within a safe or desirable range and/or to determine whether and/or
how to adjust one or more ventilator settings (e.g., to increase or
decrease respiratory support to the patient).
[0027] In some embodiments, the WOB graphic may depict
(graphically, numerically, or otherwise) the effect that changes in
one or more ventilator settings have on the work of breathing being
contributed by a patient, e.g., in order to determine whether or
not such adjustments are causing a patient to work at a level
above, within, or below an acceptable or desired range of work. The
WOB graphic may be user-friendly such that caregivers of various
degrees of technical sophistication may understand or interpret the
display and/or be able to utilize the display for implementing or
managing a respiration support strategy. Additionally, the WOB
graphic may be used in conjunction with traditional ventilation
systems and applications, e.g., pressure assisted ventilation (PAV)
applications.
[0028] The WOB graphic may be displayed via any of a variety of
media. For example, in some embodiments, the WOB graphic may be
displayed by a ventilator or a ventilator control system. In other
embodiments, the WOB graphic may be displayed on a separate display
device (e.g., separate from a ventilator). In particular
embodiments, the WOB graphic may be displayed in association with a
ventilation control system for administering a respiration support
strategy. In such embodiments, a ventilator may be connected to a
graphic user interface having a digital processor, a display
screen, and/or one or more user inputs, or the ventilator may
itself include a graphic user interface. These components may
cooperate to assist a caregiver in setting up and/or adjusting the
work of breathing being provided by a patient and/or the work of
breathing being provided the ventilator.
[0029] In some embodiments, the WOB graphic may indicate the total
work of breathing (WOB.sub.TOTAL), the patient's work of breathing
(WOB.sub.PATIENT) (neither or which, one or which, or both of which
advance or retreat along a scale) and/or the components of the
patient's WOB--an elastic WOB component (WOB.sub.PATIENT-ELASTIC)
and a resistive WOB component (WOB.sub.PATIENT-RESISTIVE). For
example, the WOB graphic may include a WOB.sub.TOTAL graphic or
indicator that that indicates the total work of breathing, a
WOB.sub.PATIENT graphic or indicator that that indicates the
patient's work of breathing, and an elastic-resistive WOB graphic
that indicates a measure of the elastic WOB component
(WOB.sub.PATIENT-ELASTIC) relative to a measure of the resistive
WOB component (WOB.sub.PATIENT-RESISTIVE). As another example, the
WOB graphic may include a WOB.sub.TOTAL graphic or indicator that
that indicates the total work of breathing, a
WOB.sub.PATIENT-ELASTIC) graphic or indicator that that indicates
the patient's work of breathing, an elastic WOB graphic that
indicates a measure of the elastic WOB component
(WOB.sub.PATIENT-ELASTIC) and a resistive WOB graphic that
indicates a measure of the resistive WOB component
(WOB.sub.PATIENT-RESISTIVE). In other embodiments, one or more
additional and/or other components of a total work of breathing
measure may be displayed, e.g., the ventilator work of breathing
(WOB.sub.VENTILATOR).
[0030] In some embodiments, the WOB graphic may include a scale
having any suitable shape and configuration (e.g., a linear scale,
a circular or semicircular scale, or an elliptical scale) and one
or more indicators that move relative to the scale to indicate one
or more work of breathing parameters. For example, the WOB graphic
may include a first indicator that moves relative to the scale to
represent a measure of WOB.sub.TOTAL, and a second indicator that
moves relative to the scale to represent a measure of
WOB.sub.PATIENT. The scale may be divided into sectors that
generally correspond to different work of breathing levels. The
sectors may be visibly discernable from each other (or at least
from immediately adjacent sectors). For example, the sectors may be
color-coded or distinctively shaded.
[0031] An elastic-resistive WOB graphic may be divided into a first
portion and a second portion, the first portion indicating the
elastic WOB component (WOB.sub.PATIENT-ELASTIC) and the second
portion indicating the resistive WOB component
(WOB.sub.PATIENT-RESISTIVE). The relative sizes of the first and
second portions of the elastic-resistive WOB graphic may
dynamically adjust to indicate the measure of the elastic WOB
component relative to the measure of the resistive WOB component.
In certain embodiments, the overall size of the elastic-resistive
WOB graphic remains constant as the relative sizes of the first and
second portions dynamically adjust.
[0032] FIGS. 1 and 2 illustrate two example embodiments of a
ventilation system including a displayed WOB graphic. More
particularly, FIG. 1 illustrates an example ventilation system
including a ventilator configured to display a work of breathing
graphic, while FIG. 2 illustrates an example ventilation system
including a ventilator and a separate module for displaying a work
of breathing graphic.
[0033] Referring to FIG. 1, a ventilation system 10a for providing
breathing assistance to a patient 12 may include a ventilator 14
configured to display a WOB graphic 16 and one or more devices for
connecting ventilator 14 to patient 12. As used throughout this
document, the term "ventilator" may refer to any device, apparatus,
or system for delivering breathing gas to a patient, e.g., a
ventilator, a respirator, a CPAP device, or a BiPAP device. The
term "patient" may refer to any person who is receiving breathing
support from a ventilation system, regardless of the medical
status, official patient status, physical location, or any other
characteristic of the person. Thus, for example, patients may
include persons under official medical care (e.g., hospital
patients), persons not under official medical care, persons
receiving care at a medical care facility, persons receiving home
care, etc.
[0034] Ventilator 14 may include a ventilation control system 18, a
display device 20, and a WOB calculation module 22. Ventilation
control system 18 may be operable to control the ventilation
support provided by ventilator 14 based on various inputs, such as
inputs received from an operator and/or data received from various
sensors, as discussed below. Display device 20 may be fully or
partially integrated with ventilator 14 and may comprise, e.g., a
touch screen display or other visual display. Display device 20 may
be configured to display various information regarding the
ventilation of patient 12, including WOB graphic 16 and/or other
information regarding the ventilation of patient 12 (e.g., tidal
volume, minute ventilation, and respiration rate). WOB graphic 16
may display one or more work of breathing measures in any suitable
manner, e.g., graphically, numerically, or otherwise. WOB graphic
16 may be a full screen display or may occupy a portion of a
display screen. For example, WOB graphic 16 may be located in a
window or a portion of a display that includes other information
regarding the ventilation of patient 12.
[0035] Display device 20 may be part of or otherwise associated
with, a graphic user interface 26. In this embodiment, graphic user
interface 26 may be configured to display WOB graphic 16 and/or
other information via display device 20 and/or provide an interface
for accepting input from human operators via display device 20
and/or other input devices (e.g., to set or modify ventilation
settings, to access data, and/or to change or configure the
display).
[0036] Patient 12 may be connected to ventilator 14 by a breathing
circuit 30 that may include an inspiration conduit 32, an
exhalation conduit 34, and/or a patient connection apparatus 36.
Patient connection apparatus 36 may include any device or devices
configured to connect breathing circuit 30 to one or more breathing
passageways of patient 12. For example, patient connection
apparatus 36 may include a patient connection tube directly
connected to the patient's trachea, an artificial airway (e.g., an
endotracheal tube or other device) inserted in the patient's
trachea, and/or a mask or nasal pillows positioned over the
patient's nose and/or mouth. In embodiments including a patient
connection tube, the patient connection tube may include a Wye (or
"Y") connector.
[0037] Ventilation system 10a may include one or more sensors 40
for sensing, detecting, and/or monitoring one or more parameters
related to the ventilation of patient 12, e.g., parameters
regarding the ventilation provided by ventilator 14 and/or
physiological parameters regarding patient 12. For example, sensors
40 may include one or more devices for measuring various parameters
of gas flowing into or out of patient 12 or ventilator 14, e.g.,
the pressure, flow rate, flow volume, temperature, gas content,
and/or humidity of such gas flow. Thus, sensors 40 may include,
e.g., one or more pressure sensors, flow meters, transducers,
and/or oxygen sensors. Sensors 40 may be located at one or more
various locations in ventilation system 10a for monitoring the
pressure and or flow of gasses flowing into and/or out of patient
12 and/or ventilator 14. For example, one or more sensors 40 may be
located in or proximate ventilator 14, breathing circuit 30, and/or
patient connection apparatus 36. For example, depending on the
particular embodiment, one or more sensors 40 may be located within
or proximate to ventilator 14, inspiration conduit 32 and/or
exhalation conduit 34 or breathing circuit 30, an artificial
airway, and/or a Wye connector.
[0038] As discussed above, ventilation control system 18 may be
operable to control the ventilation support provided by ventilator
14 based on various input received from an operator (e.g., via
graphic user interface 26 and/or other user interfaces on
ventilator 14) and/or data received from one or more sensors 40.
For example, ventilation control system 18 may regulate the
pressure and/or flow of gas delivered to a patient based at least
on data received from sensors 40.
[0039] WOB calculation module 22 may be operable to calculate or
otherwise determine one or more work of breathing measures based on
various input data, including data collected by sensors 40, as
described in greater detail below with reference to FIG. 3. Such
work of breathing measures determined by WOB calculation module 22
may then be communicated to graphic user interface 26 for display
via display device 20.
[0040] According to the embodiment shown in FIG. 2, a ventilation
system 10b for providing breathing assistance to a patient 12 may
include a ventilator 14, one or more devices for connecting
ventilator 14 to patient 12, and a separate WOB module 50.
Ventilator 14 may include a ventilation control system 18 and a
display screen 20, such as discussed above regarding the embodiment
shown in FIG. 1. Ventilation control system 18 may be operable to
control the ventilation support provided by ventilator 14 based on
various inputs, such as inputs received from an operator and/or
data received from various sensors, as discussed below. Display
device 20 may be fully or partially integrated with ventilator 14
and may comprise, e.g., a touch screen display or other visual
display. Display device 20 may be configured to display various
information regarding the ventilation of patient 12. Display device
20 may be part of or otherwise associated with, a graphic user
interface 26. In this embodiment, graphic user interface 26 may be
configured to display various information via display device 20
and/or provide an interface for accepting input from human
operators via display device 20 and/or other input devices (e.g.,
to set or modify ventilation settings, to access data, and/or to
change or configure the display).
[0041] WOB module 50 may include a display device 52, a WOB
calculation module 22, and any other suitable hardware or software
for determining and/or displaying one or more WOB measures. For
example, WOB module 50 may be configured to display a WOB graphic
16 via display device 52, e.g., a touch screen display or other
visual display. As discussed above, WOB graphic 16 may be a full
screen display or may occupy a portion of a display screen. In some
embodiments, WOB module 50 may include a graphic user interface 54,
which may be operable to display WOB graphic 16 and/or other
information via display device 52 and, in some embodiments, provide
an interface for accepting input from human operators via display
device 52 and/or other user input devices (e.g., to set or modify
various settings, access data, and/or change or configure the
display).
[0042] WOB calculation module 22 may be operable to calculate or
otherwise determine one or more work of breathing measures based on
various input data, including data collected by sensors 40. WOB
calculation module 22 may receive such input data from any suitable
component of ventilation system 10b. For example, WOB module 50 may
be communicatively coupled to one or more sensors 40 (e.g., sensors
40 located at or proximate to an artificial airway (e.g., an
endotracheal tube or other device), a Wye connector, or breathing
circuit 30) such that WOB module 50 may receive data directly from
such sensors 40, e.g., as indicated by dashed line 56.
Alternatively, WOB module 50 may be communicatively coupled to
ventilator 14 such that WOB module 50 may receive data from
ventilator 14 (e.g., as indicated by dashed line 58), which may
include data received from various sensors 40 (which data may or
may not be first processed or otherwise acted on by ventilator 14
and then communicated to WOB module 50). WOB calculation module 22
may receive data from sensors 40 directly or indirectly in any
other suitable manner. WOB calculation module 22 may then calculate
or otherwise determine one or more work of breathing measures based
on such data from sensors 40, and communicate the determined work
of breathing measures for display via display device 52.
[0043] It should be understood that components of ventilation
systems 10a and 10b may include any hardware, software, firmware or
other components suitable for providing ventilation assistance to
patient 12 and/or determining and displaying one or more work of
breathing measures. For example, ventilator 14 may include various
processors, memory devices, user inputs, status indicators, audio
devices, and/or software or other logic for providing various
ventilator functions.
[0044] FIG. 3 is a block diagram illustrating an example system for
determining and displaying work of breathing measures, according to
some embodiments. As discussed above, WOB calculation module 22 may
be operable to calculate or otherwise determine one or more work of
breathing measures based on various input data. Such input data may
include data received from sensors 40 and/or data or settings input
by an operator, indicated in FIG. 3 as operator input 60. Such WOB
measures may then be represented in a WOB graphic 16 displayed on
any suitable display device 100, e.g., display devices 20 or 52
discussed above with reference to FIGS. 1 and 2. For example, WOB
calculation module 22 may calculate measures for WOB.sub.TOTAL,
WOB.sub.PATIENT, WOB.sub.VENTILATOR, WOB.sub.PATIENT-ELASTIC,
and/or WOB.sub.PATIENT-RESISTIVE. One, some, or all of these
measures may then be displayed in a WOB graphic 16 in any suitable
manner, e.g., using graphic and/or numeric representations.
[0045] WOB calculation module 22 may include a processor 62, memory
64, and any other suitable hardware or software. Memory 64 may
store one or more WOB algorithms 66 and/or any other suitable
software or logic that may be executable by processor 60 for
calculating one or more work of breathing measures, e.g., as
discussed below.
[0046] WOB calculation module 22 may use data collected by sensors
40 to calculate or otherwise determine work of breathing measures
in any of a variety of manners. For example, in some embodiments in
which a balloon is inserted in the patient's esophagus, sensors 40
may be used to monitor pressure and volume (flow*time) at the
airway opening (e.g., at or proximate to a Wye connector). Such
data may be communicated to WOB calculation module 22, which may
determine or calculate one or more WOB measures based on such
received data.
[0047] Alternatively, WOB calculation module 22 may calculate
estimated WOB measures based on data monitored entirely external to
the patient, e.g., using WOB 66 algorithms that use data from
sensors 40 as inputs. For example, in a pressure assisted
ventilation (PAV) environment, WOB calculation module 22 may
receive data from sensors 40 positioned in or proximate to
ventilator 14 and calculate estimated WOB measures using such data
as inputs for one or more suitable PAV algorithms. Example
techniques for providing or generating PAV, which may lead to WOB
calculations, are disclosed in U.S. Pat. No. 5,107,830, which is
hereby incorporated by reference in its entirety. In addition,
example techniques for determining or approximating resistance
and/or elastance in a PAV environment, which may be used in
calculating WOB values, are disclosed in U.S. Pat. Nos. 5,884,622
and 6,837,242, which are hereby incorporated by reference in their
entirety.
[0048] Thus, in some embodiments, WOB calculation module 22 may
include or use such techniques and/or other known techniques for
calculating estimated WOB measures, which may then be displayed via
WOB graphic 16. It should be understood that WOB measures may be
measured, estimated, or otherwise determined in any other suitable
manner in both PAV and non-PAV environments.
[0049] Various example embodiments of WOB graphic 16 are
illustrated in FIGS. 4-9, as discussed in greater detail below. WOB
graphic 16 may be displayed on any suitable display device 100,
e.g., display devices 20 or 52 discussed above with reference to
FIGS. 1 and 2. Although the present disclosure discusses the
generation and/or display of a WOB graphic in connection with a
ventilator, it should be understood that the disclosed WOB graphics
may similarly be used in connection with other stand-alone systems
or devices that calculate WOB measures. WOB graphic 16 may
comprise, e.g., a graphic on a general-purpose display screen or on
a dedicated display or display device, and may be configured to
provide a user-friendly display that represents a patient's work of
breathing. However, display device 100 may additionally or
alternatively be operable to visually represent patient data, alarm
conditions, various charts, graphs, tables, and/or other such
information as may be appropriate or useful to a caregiver in
assessing a patient's respiratory or other vital functions. For
example, the display of display device 100 may be divided into
multiple sections, with one section displaying the WOB graphic 16
while one or more other sections display various other items such
as ventilator parameters, patient data, etc. However, such
information may alternatively be displayed in a non-sectored
layout, e.g., intermingled or integrated with the WOB graphic
16.
[0050] As discussed above, WOB graphic 16 may indicate the total
work of breathing (WOB.sub.TOTAL), the patient's work of breathing
(WOB.sub.PATIENT), and/or the components of the patient's WOB--an
elastic WOB component (WOB.sub.PATIENT-ELASTIC) and a resistive WOB
component (WOB.sub.PATIENT-RESISTIVE). In some embodiments, WOB
graphic 16 may include a scale having any suitable shape or
configuration (e.g., a linear scale, a circular or semicircular
scale, or an elliptical scale) and one or more indicators that move
relative to the scale to indicate one or more work of breathing
parameters. For example, WOB graphic 16 may include a WOB.sub.TOTAL
indicator that moves relative to the scale to represent a measure
of WOB.sub.TOTAL, and a WOB.sub.PATIENT indicator that moves
relative to the scale to represent a measure of WOB.sub.PATIENT.
The scale may be divided into sectors that generally correspond to
different work of breathing levels. The sectors may be visibly
discernable from each other (or at least from immediately adjacent
sectors).
[0051] The elastic-resistive WOB graphic may be divided into a
first portion and a second portion, the first portion indicating
the elastic WOB component (WOB.sub.PATIENT-ELASTIC) and the second
portion indicating the resistive WOB component
(WOB.sub.PATIENT-RESISTIVE). The overall size of the
elastic-resistive WOB graphic may remain constant as the relative
sizes of the first and second portions dynamically adjust to
indicate a measure of the elastic WOB component relative to a
measure of the resistive WOB component.
[0052] Each work of breathing measure (e.g., WOB.sub.TOTAL,
WOB.sub.PATIENT, WOB.sub.VENTILATOR, WOB.sub.PATIENT-ELASTIC,
and/or WOB.sub.PATIENT-RESISTIVE) may be calculated and/or
displayed using any suitable units or other parameter. For example,
each WOB measure may be calculated and/or displayed as Joules (J),
Joules per liter (J/L), Joules per minute (J/min) (i.e., power), or
Joules per liter per kilogram (J/L/kg) (i.e., normalized power).
Thus, it should be understood that the following discussion of WOB
measures displayed in J/L is exemplary only.
[0053] FIG. 4 illustrates an example of a WOB graphic 16a on a
display device 100, according to one embodiment of the disclosure.
WOB graphic 16a may include a scale 200, a WOB.sub.TOTAL indicator
202 for indicating a measure of the total WOB, a WOB.sub.PATIENT
indicator 204 for indicating a measure of the patient's WOB, and/or
an elastic-resistive WOB indicator 206 for indicating the elastic
and resistive WOB components of the patient's WOB. scale 200 may be
divided into a plurality of sectors that may generally correspond
to different levels of acceptability, desirability, or safety
regarding the patient's breathing. For example, such sectors may
include at least one first sector representing a sub-normal work of
breathing range, at least one second sector representing a normal
work of breathing range, and at least one third sector representing
a supra-normal work of breathing range. As another example, such
sectors may include at least one first sector representing a
sub-normal work of breathing range, at least one second sector
representing a normal work of breathing range, at least one third
sector representing a supra-normal work of breathing range, and at
least one fourth sector representing a cautionary supra-normal work
of breathing range.
[0054] In the example shown in FIG. 4, scale 200 may include four
sectors, 210, 212, 214, and 216, which correspond to a sub-normal
work of breathing range (sector 210), a normal work of breathing
range (sector 212), a supra-normal work of breathing range (sector
214), and a cautionary supra-normal work of breathing range (sector
216). Sub-normal sector 210 may represent a range in which the
patient's WOB may be below an appropriate level for administering a
proper respiratory management protocol. Normal sector 212 may
represent a range in which the patient's contributed WOB may be
within an appropriate level for administering a proper respiratory
management protocol. Supra-normal sector 214 may represent a range
in which the patient's WOB may be above an appropriate level for
administering a proper respiratory management protocol. Cautionary
supra-normal sector 216 may represent a range in which the
patient's WOB may be at a potentially harmful level. It should be
understood that in other embodiments, WOB graphic 16a may include
any number and/or type(s) of sectors corresponding to any various
conditions.
[0055] WOB.sub.TOTAL indicator 202 may comprise any pointer or
other graphic that may advance and retreat along scale 200 as the
WOB.sub.TOTAL changes over time (e.g., when a "percent support"
setting is adjusted in a PAV ventilation environment).
WOB.sub.TOTAL indicator 202 may include any suitable label or other
identifier. In some embodiments, WOB.sub.TOTAL indicator 202 may
include a numerical indication of the current WOB.sub.TOTAL
measure. In other embodiments, no such numerical indication is
displayed.
[0056] Similarly, WOB.sub.PATIENT indicator 204 may comprise any
pointer or other graphic that may advance and retreat along scale
200 as the WOB.sub.PATIENT changes over time. WOB.sub.PATIENT
indicator 204 may include any suitable label or other identifier.
In some embodiments, WOB.sub.PATIENT indicator 204 may include a
numerical indication of the current WOB.sub.PATIENT measure. In
other embodiments, no such numerical indication is displayed.
[0057] Elastic-resistive WOB indicator 206 may be divided into a
first indicator portion 220 representing a measure of
WOB.sub.PATIENT-ELASTIC, and a second indicator portion 222
representing a measure of WOB.sub.PATIENT-RESISTIVE. The relative
sizes of first and second indicator portions 220 and 222 may adjust
dynamically as the relative measures of WOB.sub.PATIENT-ELASTIC and
WOB.sub.PATIENT-RESISTIVE change over time. In some embodiments
(e.g., as such as shown in FIG. 4), elastic-resistive WOB indicator
206 may be coupled to or otherwise associated with WOB.sub.PATIENT
indicator 202, such that elastic-resistive WOB indicator 206
advances and retreats along scale 200 in coordination with
WOB.sub.PATIENT indicator 202.
[0058] In this embodiment, scale 200 is oriented horizontally and
WOB.sub.TOTAL indicator 202, WOB.sub.PATIENT indicator 204, and
elastic-resistive WOB indicator 206 move horizontally along scale
200. In other embodiments, scale 200 may be oriented, and
indicators 202, 204, and/or 206 may move, in any other direction
(e.g., vertically, diagonally, in a stepped manner, or in a curved
manner). Indicators 202, 204, and/or 206 may be positioned relative
to scale 200 in any suitable manner. For example, 202, 204, and/or
206 may be positioned on the same side of scale 200 or on opposite
sides of scale 200. As another example, one or more of indicators
202, 204, and/or 206 may be partially or fully superimposed over
scale 200 and may advance or retreat along or through sectors
210-216 to indicate one or more work of breathing measures.
Further, scale 200 and indicators 202, 204, and/or 206 may be
positioned anywhere on WOB graphic 16a.
[0059] In some embodiments, sector transition lines may divide the
respective sectors of WOB scale 200. For example, as shown in FIG.
4, sector transition lines 230, 232, 234, 236, and 238 may divide
sectors 210-216. Sector transition lines 230-238 may have any
suitable shape and orientation. For example, sector transition
lines 230-238 may be shaped to mirror or correspond to the shape or
form of one or both ends of elastic-resistive WOB indicator 206. In
other embodiments, scale 200 may not include sector transition
lines.
[0060] In some embodiments, sectors 210-216 may be visibly
discernable from each other, or at least from immediately adjacent
sectors. For example, sectors 210-216 may be color-coded, shaded,
or differently shaped such that sectors 210-216 may be visibly
distinguishable from each other. Such color coding is represented
in FIG. 4 by different levels of shading.
[0061] In an example embodiment, sector 210 may be color-coded
yellow, sector 92 may be color-coded green, sector 94 may be
color-coded yellow, and sector 96 may be color-coded orange, which
may be commensurate with good human factors. It should be
understood that any coloring may be chosen for each respective
sector. Such color-coding may be permit the caregiver to quickly
and easily determine the location of indicators 202, 204, and/or
206 along scale and/or provide the caregiver a quick indication of
the status of the ventilatory support. In other embodiments, one,
some or all of sectors 210-216 may be free from color-coding or
other types of fill.
[0062] Elastic-resistive WOB indicator 206 may have any suitable
shape and/or configuration. For example, elastic-resistive WOB
indicator 206 may comprise a box, as shown in FIG. 4, or may take
the form of a bar graph, a vertically-oriented line segment, or any
other suitable symbol or graphic representation that may advance
and retreat along sectors 210-216 to indicate measures of
WOB.sub.PATIENT-ELASTIC and/or WOB.sub.PATIENT-RESISTIVE. For
example, in one embodiment, elastic-resistive WOB indicator 206
comprises a bar or other graphic that expands in length along scale
200 to indicate a measure of WOB.sub.PATIENT. The bar or other
graphic may be divided into indicator portions 220 and 222 that may
adjust dynamically to indicate measures of WOB.sub.PATIENT-ELASTIC
and WOB.sub.PATIENT-RESISTIVE over time. In some embodiments (e.g.,
where elastic-resistive WOB indicator 206 is superimposed over
scale 200), the height of elastic-resistive WOB indicator 206 (in
the vertical direction as shown in FIG. 4) may be less than the
height of scale 200, which may increase the visual contrast between
elastic-resistive WOB indicator 206 and scale 200.
[0063] In some embodiments, the overall (or exterior) size and/or
shape of elastic-resistive WOB indicator 206 remain constant, while
the relative sizes of component portions 220 and 222 adjust
dynamically. In other embodiments, the overall (or exterior) size
and/or shape of elastic-resistive WOB indicator 206 may change over
time. For example, in embodiments in which elastic-resistive WOB
indicator 206 comprises a bar graph (e.g., extending from the left
edge of scale 200), the horizontal length of elastic-resistive WOB
indicator 206 may be dynamic.
[0064] In some embodiments, scale 200 may include a set of
numerical indices 240 to quantify the range of WOB values for each
sector 210-216. Such values may have any suitable units, e.g.,
Joules (J), Joules per liter (J/L), Joules per minute (J/min)
(i.e., power), or Joules per minute per kilogram (J/min/kg) (i.e.,
normalized power). The particular values defined by numerical
indices 240 (and thus, the ranges of each sector 210-216) may be
determined based on any suitable data, e.g., historical data. In
some embodiments, the values defined by numerical indices 240 may
be permanent for WOB graphic 16a. In other embodiments, the values
defined by numerical indices 240 may be configurable and/or
adjustable by an operator. In addition, different numerical indices
240 having different values may be used for different patients,
different respiratory management protocols, or for any other
varying parameter(s).
[0065] One example set of numerical indices 240 is shown in FIG. 4.
In this example, suppose that a normal acceptable range for a
patient's WOB (WOB.sub.PATIENT) is typically 0.3 J/L to 0.7 J/L.
Thus, the range from 0 J/L to 0.3 J/L may be deemed sub-normal.
Thus, unless there are particular reasons for allowing a patient's
WOB to fall below 0.3 J/L, a WOB.sub.PATIENT reading consistently
remaining below 0.3 J/L could signal to the caregiver that the
patient's management protocol should be reconsidered.
[0066] Further, suppose that values falling above 0.70 J/L are
generally above an acceptable level. Thus, unless there are
particular reasons for allowing a patient's WOB to rise above 0.7
J/L, a WOB.sub.PATIENT reading consistently remaining above 0.7 J/L
could signal to the caregiver that the patient's management
protocol should be reconsidered. Further, suppose that values
falling above 1.0 J/L are deemed to be particularly cautionary or
potentially harmful. Thus, unless there are particular reasons for
allowing a patient's WOB to rise above 1.0 J/L, a WOB.sub.PATIENT
reading consistently remaining above 1.0 J/L could signal to the
caregiver that the patient's management protocol is particular
cautionary or potentially harmful and should thus be
reconsidered.
[0067] Thus, in this example, the set of numerical indices 240
includes the values 0, 0.3, 0.7, 1.0, and 2.0 positioned proximate
the corresponding sector transition lines 230-238. A graphic
representation of the unit of measurement, e.g., Joules/liter
(J/L), may be included, as shown in FIG. 4, or may be omitted.
Numerical indices 240 may be otherwise positioned and/or configured
to correspond to appropriate sector transitions or other points
within sectors 210-216 of WOB graphic 16a.
[0068] In some embodiments, WOB graphic 16a may include a WOB units
selector 242 (e.g., a button) providing an interface allowing an
operator to select from multiple units for which to display WOB
measures on WOB graphic 16a. For example, selecting button 242 may
open a window allowing the user to select from different
units--e.g., Joules (J), Joules per liter (J/L), Joules per minute
(J/min), or Joules per minute per kilogram (J/min/kg)--for which
WOB measures are displayed in WOB graphic 16a. When an operator
selects a particular unit, the values and/or units displayed in
numerical indices 240 may be automatically update as appropriate.
In this manner, this operator may select a desired units setting
for WOB measures displayed in WOB graphic 16a.
[0069] Like scale 200, elastic-resistive WOB indicator 206 may be
configured such that indicator portions 220 and 222 are visibly
discernable from each other, such that a caregiver can quickly and
easily identify the relative magnitudes of WOB.sub.PATIENT-ELASTIC
and WOB.sub.PATIENT-RESISTIVE. In some embodiments, indicator
portions 220 and 222 are shaded in two different colors (or two
different shades of the same basic color). However, it should be
understood that indicator portions 220 and 222 may be otherwise
colored or shaded, or may not be colored or shaded at all.
[0070] Indicator portions 220 and 222 may be divided by a reader
250, which may dynamically move within elastic-resistive WOB
indicator 206 (e.g., to the left or right) to adjust the relative
sizes of indicator portions 220 and 222 as the relative magnitude
and/or percentage of the resistive and elastic WOB components
change over time. In some embodiments, reader 250 may double as, or
be otherwise associated with WOB.sub.PATIENT indicator 204. In
other embodiments, reader 250 may be distinct from WOB.sub.PATIENT
indicator 204. In other embodiments, a leading or trailing line of
elastic-resistive WOB indicator 206, or any other appropriate
graphic representation within or associated with elastic-resistive
WOB indicator 206, may serve as WOB.sub.PATIENT indicator 204. For
example, the leading end (here, the right-most boundary or
indicator portion 222) may serve as WOB.sub.PATIENT indicator
204.
[0071] In other embodiments, elastic-resistive WOB indicator 206
may simply comprise a line or other suitable indicating means, and
the patient's resistive and/or elastic WOB components may be
graphically displayed separately, as numerical values of an
appropriate unit of measure, or in any other suitable manner.
[0072] In some embodiments of the present disclosure, the caregiver
may be able to easily identify the relative percentages of the
patient's resistive work and elastic work from indicator portions
220 and 222, respectively, of elastic-resistive WOB indicator 206.
By dividing elastic-resistive WOB indicator 206 into resistive and
elastic WOB components 220 and 222, a caregiver may be able to
easily determine whether a patient is exerting too much or too
little resistive or elastic work, which in turn may assist the
caregiver in diagnosing the patient's condition and/or adjusting
the ventilation strategy.
[0073] In some embodiments, WOB graphic 16a may include one or more
display legends that may include any desired graphical
representations to assist the caregiver in better understanding WOB
graphic 16a. For example, as shown in FIG. 4, a display legend 260
may indicate that indicator portions 220 and 222 of
elastic-resistive WOB indicator 206 represent the elastic WOB
component (illustrated as "WOB.sub.E") and the resistive WOB
component (illustrated as "WOB.sub.R"), respectively, of the
patient's WOB. In other embodiments, symbols or legends indicating
that indicator portions 220 and 222 represent the elastic and
resistive WOB components may be located in or adjacent indicator
portions 220 and 222 (such as shown in the embodiment of FIG. 6,
for example). Similarly, display legend 260 or another display
legend may explain the color-coding of sectors 210-216 of scale
200.
[0074] FIG. 5 illustrates another example of a WOB graphic 16b on a
display device 100, according to one embodiment of the disclosure.
WOB graphic 16b may be similar to WOB graphic 16a shown in FIG. 4
and discussed above, but may additionally include a
WOB.sub.VENTILATOR indicator 270 that indicates a measure of the
ventilator's WOB. WOB.sub.VENTILATOR indicator 270 may comprise any
pointer or other graphic that may advance and retreat along scale
200 as the WOB.sub.VENTILATOR changes over time. WOB.sub.VENTILATOR
indicator 270 may include any suitable label or other identifier.
In some embodiments, WOB.sub.VENTILATOR indicator 270 may include a
numerical indication of the current WOB.sub.VENTILATOR measure. In
other embodiments, no such numerical indication is displayed.
[0075] FIG. 6 illustrates another example of a WOB graphic 16c on a
display device 100, according to another embodiment of the
disclosure. WOB graphic 16c may include a scale 300, a
WOB.sub.TOTAL indicator 302 for indicating a measure of the total
WOB, a WOB.sub.PATIENT indicator 304 for indicating a measure of
the patient's WOB, and/or an elastic-resistive WOB indicator 306
for indicating the elastic and resistive WOB components of the
patient's WOB.
[0076] Scale 300 and indicators 302-306 may be analogous to scale
200 and indicators 202-206 shown in FIG. 4. Scale 300 may extend in
an arc, and may be divided into sections 310-316, which may be
similar to sections 210-216 discussed above. WOB.sub.TOTAL
indicator 302 may comprise a pointer that rotates relative to
curved scale 300 to indicate a measure of the total WOB. Similarly,
WOB.sub.PATIENT indicator 304 may comprise a pointer that rotates
relative to curved scale 300 to indicate a measure of the patient's
WOB.
[0077] Elastic-resistive WOB indicator 306 may be divided into
indicator portions 320 and 322, which may indicate the elastic and
resistive WOB components of the patient's WOB, e.g., as discussed
above regarding indicator portions 220 and 222 of elastic-resistive
WOB indicator 206. The relative sizes (e.g., the length and/or
width) of indicator portions 320 and 322 may dynamically change to
indicate the current relative measures of elastic and resistive WOB
components, e.g., as discussed above regarding elastic-resistive
WOB indicator 206. However, unlike elastic-resistive WOB indicator
206, elastic-resistive WOB indicator 306 may remain stationary
(rather than moving along scale 300). In addition, in some
embodiments, an indication that indicator portions 320 and 322
represent the elastic and resistive WOB components is located in or
adjacent indicator portions 320 and 322. For example, as shown in
FIG. 6, the letters "E" and "R" may be displayed in indicator
portions 320 and 322 to indicate that that indicator portions 320
and 322 represent the elastic and resistive WOB components,
respectively. In other embodiments, WOB graphic 16c may include one
or more display legends to provide such information, e.g., as
discussed above regarding display legend 260.
[0078] FIG. 7 illustrates another example of a WOB graphic 16d on a
display device 100, according to another embodiment of the
disclosure. WOB graphic 16d may include a scale 400, a
WOB.sub.TOTAL indicator 402 for indicating a measure of the total
WOB, a WOB.sub.PATIENT indicator 404 for indicating a measure of
the patient's WOB, and/or an elastic-resistive WOB indicator 406
for indicating the elastic and resistive WOB components of the
patient's WOB. Scale 400 and indicators 402-406 may be analogous to
scale 300 and indicators 302-306 shown in FIG. 6. For example,
scale 400 may extend in an arc, and may be divided into sections
410-416. WOB.sub.TOTAL indicator 402 may move in an arced path
along an inner perimeter of scale 400. In other embodiments,
WOB.sub.TOTAL indicator 402 may move along an outer perimeter of
scale 400. WOB.sub.PATIENT indicator 404 may move in an arced path
along an outer scale 400, and may be coupled to elastic-resistive
WOB indicator 406 such that elastic-resistive WOB indicator 406
moves along with WOB.sub.PATIENT indicator 404. In other
embodiments, elastic-resistive WOB indicator 406 and/or
WOB.sub.PATIENT indicator 404 may move along an inner perimeter of
scale 400.
[0079] Elastic-resistive WOB indicator 406 may be divided into
indicator portions 420 and 422, which may indicate the elastic and
resistive WOB components of the patient's WOB. The relative sizes
of indicator portions 420 and 422 may dynamically change to
indicate the current relative measures of elastic and resistive WOB
components, e.g., as discussed above regarding elastic-resistive
WOB indicator 206. In addition, in some embodiments, an indication
(e.g., the letters "E" and "R") that indicator portions 420 and 422
represent the elastic and resistive WOB components may be located
in or adjacent indicator portions 420 and 422, such as discussed
above regarding FIG. 6.
[0080] FIG. 8 illustrates another example of a WOB graphic 16e on a
display device 100, according to another embodiment of the
disclosure. WOB graphic 16e may include a scale 500, a
WOB.sub.TOTAL indicator 502 for indicating a measure of the total
WOB, a WOB.sub.PATIENT indicator 504 for indicating a measure of
the patient's WOB, and/or an elastic-resistive WOB indicator 506
for indicating the elastic and resistive WOB components of the
patient's WOB. Scale 500 and indicators 502-506 may be analogous to
scale 200 and indicators 202-206 shown in FIG. 4. Scale 500 may
extend in an elliptical or other curved shape, and may be divided
into sections 510-516. WOB.sub.TOTAL indicator 502 may move in a
curved path along an outer perimeter of scale 500. In other
embodiments, WOB.sub.TOTAL indicator 502 may move along an inner
perimeter of scale 500. WOB.sub.PATIENT indicator 504 may move in a
curved path along an inner scale 500. In other embodiments,
WOB.sub.PATIENT indicator 504 may move along an outer perimeter of
scale 500.
[0081] Elastic-resistive WOB indicator 506 may be divided into
indicator portions 520 and 522, which may indicate the elastic and
resistive WOB components of the patient's WOB. The relative sizes
of indicator portions 520 and 522 may dynamically change to
indicate the current relative measures of elastic and resistive WOB
components. Like elastic-resistive WOB indicator 306 shown in FIG.
6, elastic-resistive WOB indicator 506 may remain stationary
(rather than moving along scale 500). As discussed above, an
indication (e.g., the letters "E" and "R") that indicator portions
520 and 522 represent the elastic and resistive WOB components may
be located in or adjacent indicator portions 520 and 522.
[0082] FIG. 9 illustrates another example of a WOB graphic 16f on a
display device 100, according to another embodiment of the
disclosure. WOB graphic 16f may include one or more scales for
indicating the patient's WOB (WOB.sub.PATIENT), the ventilator's
WOB (WOB.sub.VENTILATOR), and/or the total WOB (WOB.sub.TOTAL)/ For
example, as shown in FIG. 9, WOB graphic 16f may include (a) a
first scale 600a for indicating the patient's WOB (WOB.sub.PATIENT)
and/or the elastic and resistive WOB components of WOB.sub.PATIENT,
and (b) a second scale 600b for indicating the ventilator's WOB
(WOB.sub.VENTILATOR). In another embodiment, WOB graphic 16f may
include a third scale for indicating the total WOB (WOB.sub.TOTAL).
In other embodiments, WOB graphic 16f may include any one, two or
all three of such scales indicating WOB.sub.PATIENT,
WOB.sub.VENTILATOR, and/or WOB.sub.TOTAL.
[0083] Regarding scale 600a shown in FIG. 9, a WOB.sub.PATIENT
indicator 604 in the form of a bar may advance and retreat along
scale 600a to indicate a measure of the patient's WOB,
WOB.sub.PATIENT. WOB.sub.PATIENT indicator 604 may be divided into
indicator portions 620 and 622, which may indicate the elastic and
resistive WOB components of the patient's WOB, respectively. The
sizes of indicator portions 620 and 622 may dynamically change to
indicate the current relative measures of elastic and resistive WOB
components. An indication (e.g., the letters "E" and "R") that
indicator portions 620 and 622 represent the elastic and resistive
WOB components may be located in or adjacent indicator portions 620
and 622. Alternatively, WOB graphic 16f may include legend (e.g.,
as discussed above with respect to FIG. 4) to indicate that
portions 620 and 622 represent the elastic and resistive WOB
components of the patient's WOB. Indicator portions 620 and 622 may
be color-coded or otherwise visually distinct, e.g., as described
above. Scale 600a may include a set of numerical indices (e.g.,
similar to numerical indices 240 shown in FIG. 4) to quantify
ranges of WOB values for pre-determined sectors of scale 600a
(e.g., 0 to 0.3, 0.3 to 0.7, 0.7 to 1.0, and 1.0 to 2.0). Regarding
scale 600b, a WOB.sub.VENTILATOR indicator 624 in the form of a bar
may advance and retreat along scale 600b to indicate a measure of
the ventilator's WOB, WOB.sub.VENTILATOR. WOB.sub.VENTILATOR
indicator 624 may be color-coded or otherwise visually distinct
from indicator portions 620 and 622 of WOB.sub.PATIENT indicator
604. In other embodiments, WOB graphic 16f may not include scale
600b or WOB.sub.VENTILATOR indicator 624. Like scale 600a, scale
600b may include a set of numerical indices to quantify ranges of
WOB values for pre-determined sectors of scale 600b. In other
embodiments, scales 600a and 600b may share a common set or
numerical indices, or may not include numerical indices.
[0084] Although the disclosed embodiments have been described in
detail, it should be understood that various changes, substitutions
and alterations can be made herein without departing from the
spirit and scope of the disclosure as illustrated by the following
claims.
* * * * *