US3834381A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compliance compensated ventilation system
Assignee: Puritan Bennett Corp
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Filing: 1972-08-25
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Granted: 1974-09-10
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Expires: 1992-08-25
Abstract
Abstract Method and apparatus for maintaining a substantially constant volume of gas flow to a patient, particularly an infant, with a volume-limited ventilation system, regardless of changes in the pressure and compliance of the delivery system or patient. The delivery pressure is monitored and combined with corrective factors derived from compliance changes in the system, gas heating under pressure, initial gas pressure, and gas overflow due to inherent system delays. The combined corrections are used to compute a compliance-compensation volume which is the volume of gas trapped within the gas delivery system. The compliance compensation volume is subtracted from the apparent volume of gas delivered to the system to determine the volume of gas actually delivered to a patient. The delivered volume is then compared with a desired reference volume and is terminated when they are equal.
Inventors
- 👤 K Peterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:27
CPC Classifications
A; A61; A61M; A61M16/00; A61M16/021; A61M16/022; A61M16/024; A61M16/0057; A61M16/0075; A61M16/0003; A61M2016/0027; A61M2016/003; A61M2016/0033; A61M2230/00; A61M2230/40; A61M2230/46
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
105 words
A method of compliance compensation for a volume-limited ventilator, comprising the steps of: monitoring the apparent volume delivered by the ventilator; monitoring the delivery system pressure of the ventilator; computing an intermediate compliance volume determined by the algebraic product of said system pressure and a total machine compliance of the ventilator; deriving a time-decreasing compensation factor dependent upon the substantially transient heating of said gas due to rapid system pressurization; multiplying said intermediate compliance volume by said timedecreasing compensation factor to produce a compensated compliance volume; and subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator.
Claim 2
Independent Claim
105 words
A method of compliance compensation for a volume-limited ventilator, comprising the steps of: monitoring the apparent volume delivered by the ventilator; monitoring the delivery system pressure of the ventilator; computing an intermediate compliance volume determined by the algebraic product of said system pressure and a total machine compliance of the ventilator; deriving a time-decreasing compensation factor dependent upon the substantially transient heating of said gas due to rapid system pressurization; multiplying said intermediate compliance volume by said timedecreasing compensation factor to produce a compensated compliance volume; and subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator.
Claim 3
Dependent Claim
64 words
A method of compliance compensation as defined in claim 1, and further including the steps of independently subtracting said compensated compliance volume from said apparent volume to determine independently an approximation to said actual delivered volume; differentiating said independently determined approximate delivered volume to determine the flow rate of said approximate delivered volume; and using said flow rate to correct said actual delivered income.
Claim 4
Dependent Claim
36 words
A method of compliance compensation as defined in claim 1, including the steps of: comparing said actual delivered volume with a predetermined desired volume; and terminating volume delivery when said delivered volume equal said desired volume.
Claim 5
Dependent Claim
32 words
The compliance compensation system of claim 1, including: means for comparing said actual delivered volume with a predetermined desired volume; and terminating volume delivery when said delivered volume equals said desired volume.
Claim 6
Independent Claim
133 words
A method of compliance compensation for a volume limited ventilator, comprising the steps of: monitoring the apparent volume delivered by the ventilator; monitoring the delivery system pressure of the ventilator; computing an intermediate compliance volume determined by the algebraic product of said system pressure and a total machine compliance of the ventilator; compensating said intermediate compliance volume for the heating of said gas under said system pressure by multiplying said intermediate compliance volume by the factor 1Ae (t/T ) where A is an empirically derived constant for each ventilator, t is the time, and Tc is the thermal cooling time constant of the gas in the ventilator the result being a compensated compliance volume; and subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator.
Claim 7
Independent Claim
133 words
A method of compliance compensation for a volume limited ventilator, comprising the steps of: monitoring the apparent volume delivered by the ventilator; monitoring the delivery system pressure of the ventilator; computing an intermediate compliance volume determined by the algebraic product of said system pressure and a total machine compliance of the ventilator; compensating said intermediate compliance volume for the heating of said gas under said system pressure by multiplying said intermediate compliance volume by the factor 1Ae (t/T ) where A is an empirically derived constant for each ventilator, t is the time, and Tc is the thermal cooling time constant of the gas in the ventilator the result being a compensated compliance volume; and subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator.
Claim 8
Dependent Claim
64 words
A method of compliance compensation as defined in claim 5, and further including the steps of: independently subtracting said compensated compliance volume from said apparent volume to determine independently an approximation to said actual delivered volume; differentiating said independently determined approximately delivered volume to determine the flow rate of said approximate delivered volume; and using said flow rate to correct said actual delivered volume.
Claim 9
Dependent Claim
112 words
A compliance compensation system for a volume-limited ventilator comprising: means for monitoring an apparent volume delivered by the ventilator; means for monitoring delivery system pressure of the ventilator; means for computing an intermediate compliance volume determined by the algebraic product of said system pressure and a total machine compliance of the ventilator; means for deriving a time-decreasing compensation factor dependent upon the substantially transient heating of said gas due to rapid system pressurization; means for multiplying said intermediate compliance volume by said time-decreasing compensation factor to produce a compensated compliance volume; and means for subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator.
Claim 10
Dependent Claim
112 words
A compliance compensation system for a volume-limited ventilator comprising: means for monitoring an apparent volume delivered by the ventilator; means for monitoring delivery system pressure of the ventilator; means for computing an intermediate compliance volume determined by the algebraic product of said system pressure and a total machine compliance of the ventilator; means for deriving a time-decreasing compensation factor dependent upon the substantially transient heating of said gas due to rapid system pressurization; means for multiplying said intermediate compliance volume by said time-decreasing compensation factor to produce a compensated compliance volume; and means for subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator.
Claim 11
Dependent Claim
62 words
The compliance compensation system of claim 7 including: means for independently subtracting said compensated compliance volume from said apparent volume to independently determine an approximation to said actual delivered volume; means for differentiating said independently determined approximate delivered volume to determine the flow rate of said approximate delivered volume; and means for using said flow rate to correct said actual delivered volume.
Claim 12
Dependent Claim
213 words
A compliance comPensation system for a volume limited ventilator comprising: means for monitoring an apparent volume delivered by the ventilator; means for monitoring delivery system pressure of the ventilator; means for computing an intermediate compliance volume determined by the algebraic product of said system pressure and a tool machine compliance of the ventilator; means for compensating said intermediate compliance volume for the heating of said gas under said system pressure by multiplying said intermediate compliance volume by the factor 1-Ae (t/T ) where A is an empirically derived constant for each ventilator, t is the time, and Tc is the thermal cooling time constant of the gas in the ventilator the result being a compensated compliance volume; means for subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator; means for independently subtracting said compensated compliance volume from said apparent volume to independently determine an approximation to said actual delivered volume; means for independnetly subtracting said compensated compliance volume from said apparent volume to independently determine an approximation to said actual delivered volume; means for differentiating said independently determined approximate delivered volume to determine the flow rate of said approximate delivered volume; and means for using said flow rate to correct said actual delivered volume;
Claim 13
Dependent Claim
213 words
A compliance comPensation system for a volume limited ventilator comprising: means for monitoring an apparent volume delivered by the ventilator; means for monitoring delivery system pressure of the ventilator; means for computing an intermediate compliance volume determined by the algebraic product of said system pressure and a tool machine compliance of the ventilator; means for compensating said intermediate compliance volume for the heating of said gas under said system pressure by multiplying said intermediate compliance volume by the factor 1-Ae (t/T ) where A is an empirically derived constant for each ventilator, t is the time, and Tc is the thermal cooling time constant of the gas in the ventilator the result being a compensated compliance volume; means for subtracting said compensated compliance volume from said apparent volume to determine the actual delivered volume of said ventilator; means for independently subtracting said compensated compliance volume from said apparent volume to independently determine an approximation to said actual delivered volume; means for independnetly subtracting said compensated compliance volume from said apparent volume to independently determine an approximation to said actual delivered volume; means for differentiating said independently determined approximate delivered volume to determine the flow rate of said approximate delivered volume; and means for using said flow rate to correct said actual delivered volume;
Claim 14
Dependent Claim
32 words
The compliance compensation system of claim 9 including: means for comparing said actual delivered volume with a predetermined desired volume; and terminating volume delivery when said delivery volume equals said desired volume.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |