DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Objections
Claims 2-9 and 11-14 are objected to because of the following informalities:
In all dependent claims “A system” or “A method” should be “The system” and “The method”, respectively.
Appropriate correction is required.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1, 7-10, and 15 is/are rejected under 35 U.S.C. 102(a)(1) and (a)(2) as being anticipated by Clemensen et al. (US 20200359935 A1).
Regarding claim 1, Clemensen discloses a system for determining a level of oxygen consumption of a patient (Oxygen Consumption and Energy Expenditure Monitoring; title), comprising:
an inhalation limb configured to transport a first gas for inhalation by a patient ([0105] The humidified air/O2 mix flows into the patient 102 via one branch of the Y-piece attachment 106; figure 1);
an exhalation limb configured to transport a second gas comprising gas exhaled by the patient ([0105] then back out through the second branch of the Y-piece attachment 106; figure 1);
a patient interface assembly connected to the inhalation limb and the exhalation limb ([0105] Y-piece attachment 106; figure 1), the patient interface assembly to transport the first gas to the patient and the second gas from the patient (see [0105] and figure 1);
a first oxygen sensor configured to measure a concentration of oxygen in the second gas at a first sampling region ([0105] A sample of the expiration gases is diverted from the mixing chamber 134 or exit port via expiration sampling line 136 and measured by the O2/CO2 sensor 110 of the VO2 device 108; figure 1. [0103] The VO2 system 100 enables the patient 102 to use a novel VO2 device 108 that includes an O2/CO2 sensor 110 that has an O2 sensor (e.g., a laser diode sensor));
a first carbon dioxide sensor configured to measure a concentration of carbon dioxide in the second gas at a second sampling region ([0105] A sample of the expiration gases is diverted from the mixing chamber 134 or exit port [114] via expiration sampling line 136 and measured by the O2/CO2 sensor 110 of the VO2 device 108; figure 1. [0103] The VO2 system 100 enables the patient 102 to use a novel VO2 device 108 that includes an O2/CO2 sensor 110 that has an O2 sensor (e.g., a laser diode sensor) with CO2 module (e.g., a nondispersive infrared sensor or NDIR));
a flow rate sensor configured to measure a flow rate of the first gas or the second gas ([0104] The mixed air and oxygen flow out of the ventilator 104 and are measured by an inspiratory flowmeter 120, which can be a differential pressure type pneumotach, e.g., a device with a screen inserted in the fluid flow that creates a known pressure drop directly proportional to the fluid velocity. The flowmeter 120 is connected to the VO2 device 108 using double-lumen rubber tubing 126 and is used for taking measurements at the flowmeter 120 to the device 108; figure 1); and
a processor ([0114] Software for controlling the VO2 system 100 can be stored on and executed by the controller 140, and can include setup, calibration, and measurement options; figure 1) configured to determine a level of oxygen consumption of the patient ([0109] The VO2 system 100 determines both inspired volume flow (V′I) and average FIO2 accurately, effectively coping with fluctuations in FIO2 from the ventilator 104. The VO2 system 100 measures inspiratory flow of dry gas corrected for changing viscosity when FIO2 changes, and flow-weighted FIO2 corrected for flow-gas delay. Expired concentrations (FEO2 and FECO2) are measured at the outlet of the mixing chamber 134. By combining FIO2 and FICO2 (which is generally close to zero) with time shifted FEO2 and FECO2 it is possible to determine V′E, V′O2, V′CO2, as well as derived parameters including respiratory quotient (RQ) and resting energy expenditure (REE) of the patient; figure 1; see equations (1)-(10)) using an indication of a concentration of oxygen in the first gas ([0107] The tubes connecting the VO2 device 108 and inspiration fluid circuit (i.e., the inspiration sampling line 122 for measurement of the inspired oxygen concentration FIO2). [0104] The inspiration sampling line 122 takes a sample before the humidifier 124, so that the O2/air mixture sample is upstream of the humidifier 124. The sample taken at the upstream sampling point is therefore dry inspiratory gas, which is analyzed by the O2/CO2 sensor 110; figure 1), an indication of a concentration of carbon dioxide in the first gas ([0109] FICO2. [0104] The inspiration sampling line 122 takes a sample before the humidifier 124, so that the O2/air mixture sample is upstream of the humidifier 124. The sample taken at the upstream sampling point is therefore dry inspiratory gas, which is analyzed by the O2/CO2 sensor 110; figure 1) and data obtained via the first oxygen sensor ([0109] Expired concentrations (FEO2 and FECO2) are measured at the outlet of the mixing chamber 134; figure 1), the first carbon dioxide sensor ([0109] Expired concentrations (FEO2 and FECO2) are measured at the outlet of the mixing chamber 134; figure 1) and the flow rate sensor ([0109] The VO2 system 100 determines both inspired volume flow (V′I)).
Regarding claim 7, Clemensen discloses a system according to claim 1, wherein the first carbon dioxide sensor is a capnography device ([0103] CO2 module (e.g., a nondispersive infrared sensor or NDIR)).
Regarding claim 8, Clemensen discloses a system according to claim 7, wherein the capnography device is a sidestream capnography device ([0105] A sample of the expiration gases is diverted from the mixing chamber 134 or exit port via expiration sampling line 136 and measured by the O2/CO2 sensor 110 of the VO2 device 108. Examiner notes first carbon dioxide sensor is a sidestream capnography device the senor samples a portion of the expiration gas).
Regarding claim 9, Clemensen discloses a system according to claim 1, further comprising a patient y-connector ([0103] Y-piece attachment 106; figure 1) comprising a first port connected to an end of the inhalation limb ([0105] The humidified air/O2 mix flows into the patient 102 via one branch of the Y-piece attachment 106; figure 1), a second port connected to an end of the exhalation limb ([0105] then back out through the second branch of the Y-piece attachment 106; figure 1) and a third port connected to an end of the patient interface assembly (see figure 1, port between Y-piece 106 and patient 102).
Regarding claim 10, Clemensen discloses a computer-implemented method for determining a level of oxygen consumption of a patient (Oxygen Consumption and Energy Expenditure Monitoring; title. [0114] Software for controlling the VO2 system 100 can be stored on and executed by the controller 140, and can include setup, calibration, and measurement options; figure 1), comprising:
receiving first oxygen concentration data indicative of a concentration of oxygen in a first gas to be inhaled by a patient (0107] The tubes connecting the VO2 device 108 and inspiration fluid circuit (i.e., the inspiration sampling line 122 for measurement of the inspired oxygen concentration FIO2). [0104] The inspiration sampling line 122 takes a sample before the humidifier 124, so that the O2/air mixture sample is upstream of the humidifier 124. The sample taken at the upstream sampling point is therefore dry inspiratory gas, which is analyzed by the O2/CO2 sensor 110; figure 1);
receiving first carbon dioxide data indicative of a concentration of carbon dioxide in the first gas ([0109] By combining FIO2 and FICO2 (which is generally close to zero) with time shifted FEO2 and FECO2 it is possible to determine V′E, V′O2, V′CO2. [0104] The inspiration sampling line 122 takes a sample before the humidifier 124, so that the O2/air mixture sample is upstream of the humidifier 124. The sample taken at the upstream sampling point is therefore dry inspiratory gas, which is analyzed by the O2/CO2 sensor 110; figure 1);
receiving second oxygen concentration data indicative of a concentration of oxygen in a second gas comprising gas exhaled by the patient ([0109] Expired concentrations (FEO2 and FECO2) are measured at the outlet of the mixing chamber 134; figure 1), the concentration of oxygen of the second gas measured using an oxygen sensor at a first sampling region ([0105] A sample of the expiration gases is diverted from the mixing chamber 134 or exit port via expiration sampling line 136 and measured by the O2/CO2 sensor 110 of the VO2 device 108; figure 1. [0103] The VO2 system 100 enables the patient 102 to use a novel VO2 device 108 that includes an O2/CO2 sensor 110 that has an O2 sensor (e.g., a laser diode sensor));
receiving second carbon dioxide data indicative of a concentration of carbon dioxide in the second gas ([0109] Expired concentrations (FEO2 and FECO2) are measured at the outlet of the mixing chamber 134; figure 1), the concentration of carbon dioxide in the second gas measured using a first carbon dioxide sensor at a second sampling region ([0105] A sample of the expiration gases is diverted from the mixing chamber 134 or exit port [114] via expiration sampling line 136 and measured by the O2/CO2 sensor 110 of the VO2 device 108; figure 1. [0103] The VO2 system 100 enables the patient 102 to use a novel VO2 device 108 that includes an O2/CO2 sensor 110 that has an O2 sensor (e.g., a laser diode sensor) with CO2 module (e.g., a nondispersive infrared sensor or NDIR));
receiving flow rate data indicative of a flow rate of the first gas ([0104] The mixed air and oxygen flow out of the ventilator 104 and are measured by an inspiratory flowmeter 120, which can be a differential pressure type pneumotach, e.g., a device with a screen inserted in the fluid flow that creates a known pressure drop directly proportional to the fluid velocity. The flowmeter 120 is connected to the VO2 device 108 using double-lumen rubber tubing 126 and is used for taking measurements at the flowmeter 120 to the device 108; figure 1. [0109] The VO2 system 100 determines both inspired volume flow (V′I)); and
determining, based on the received data, a level of oxygen consumption of the patient ([0109] The VO2 system 100 determines both inspired volume flow (V′I) and average FIO2 accurately, effectively coping with fluctuations in FIO2 from the ventilator 104. The VO2 system 100 measures inspiratory flow of dry gas corrected for changing viscosity when FIO2 changes, and flow-weighted FIO2 corrected for flow-gas delay. Expired concentrations (FEO2 and FECO2) are measured at the outlet of the mixing chamber 134. By combining FIO2 and FICO2 (which is generally close to zero) with time shifted FEO2 and FECO2 it is possible to determine V′E, V′O2, V′CO2, as well as derived parameters including respiratory quotient (RQ) and resting energy expenditure (REE) of the patient; figure 1; see equations (1)-(10)).
Regarding claim 15, Clemensen discloses a computer program product comprising a non-transitory computer readable medium, the computer readable medium having computer readable code embodied therein, the computer readable code being configured such that, on execution by a suitable computer or processor ([0015] The system also includes a computing device with a memory configured to store instructions and a processor to execute the instructions to perform operations of calculating a transport delay time between inhalation and exhalation gas sample points, transmitting a signal to the selector valve to selectively connect either the inhalation fluid sampling line or the exhalation fluid sampling line to the sensing path, receiving data representing oxygen content and carbon dioxide content over a period of time, calculating oxygen consumption data over the period of time from the data representing oxygen content and carbon dioxide content and from the transport delay time, and displaying the oxygen consumption data), the computer or processor is caused to perform the method of claim 10 (see claim 10 above. [0114] Software for controlling the VO2 system 100 can be stored on and executed by the controller 140, and can include setup, calibration, and measurement options).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 2-6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Clemensen et al. (US 20200359935 A1) as applied to claim 1 above, and further in view of Vicario et al. (US 20210169370 A1).
Regarding claim 2, Clemensen discloses a system according to claim 1, further comprising a first mixing chamber configured to receive a portion of the second gas ([0105] A small mixing chamber 134 may be attached to the ventilator exit port 114 and mixes the expired gas as it exits the ventilator 104. A sample of the expiration gases is diverted from the mixing chamber 134 or exit port via expiration sampling line 136 and measured by the O2/CO2 sensor 110 of the VO2 device 108; figure 1), but is silent as to the first mixing chamber comprising one or more of: the first oxygen sensor; and a second carbon dioxide sensor configured to measure a concentration of carbon dioxide in the portion of the second gas to be used for verification of the concentration of carbon dioxide measured using the first carbon dioxide sensor.
However, Vicario teaches a system for determining a rate of oxygen consumption VO2 (abstract) comprising a mixing chamber configured to receive exhaled gas ([0018] system 100 includes a mixing chamber used for gas analysis (e.g., CO2 and O2 concentration measurements). The mixing chamber may be made small and relatively portable; figure 1 and 3-4) and comprising an oxygen sensor ([0025] In some embodiments, the one or more O2 concentration sensor 45 is configured to output signals related to O2 concentration in the exhaled gas in the mixing chamber. In some embodiments, sensor(s) 40 include one or more CO2 concentration sensors 47 (shown in FIGS. 3-4) configured to output signals related to CO2 concentration in the exhaled gas; figure 3-4).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the mixing chamber of Clemensen to implement the first O2 sensor at the mixing chamber in order to output signals related to O2 concentration in the exhaled gas directly at the mixing chamber, as taught by Vicario [0025].
Regarding claim 3, modified Clemensen teaches a system according to claim 2, Clemensen teaches wherein the first mixing chamber is configured to receive a portion of the second gas via a connection with the patient interface assembly and via a connection with the exhalation limb ([0105] The humidified air/O2 mix flows into the patient 102 via one branch of the Y-piece attachment 106 and then back out through the second branch of the Y-piece attachment 106. The pressure of the expiration gas can be measured at the Y-piece attachment 106 via pressure line 132, or another place in the inspiratory limb of the circuit. The expired gas passes through an optional bacterial filter 130, and back through the ventilator 104 and out through the ventilator exit port 114. A small mixing chamber 134 may be attached to the ventilator exit port 114 and mixes the expired gas as it exits the ventilator 104; figure 1).
Regarding claim 4, modified Clemensen teaches a system according to claim 2, further comprising:
a mechanical ventilator ([0104] ventilator 104; figure 1);
wherein the inhalation limb and the exhalation limb are connected to the mechanical ventilator (see figure 1 and [0104-0105]), and wherein one or more of the following conditions are satisfied:
(a) the first mixing chamber is configured to receive a portion of the second gas via a connection with an exhaust of the mechanical ventilator ([0105] A small mixing chamber 134 may be attached to the ventilator exit port 114 and mixes the expired gas as it exits the ventilator 104; figure 1).
Regarding claim 5, Clemensen discloses a system according to claim 1, but is silent as to further comprising one or more of:
(a) a second oxygen sensor configured to measure the concentration of oxygen in the first gas at a third sampling region; and
(b) a third carbon dioxide sensor configured to measure the concentration of carbon dioxide in the first gas at a fourth sampling region.
However, Vicario teaches a system for determining a rate of oxygen consumption VO2 (abstract) comprising a mixing chamber ([0018] system 100 includes a mixing chamber used for gas analysis (e.g., CO2 and O2 concentration measurements). The mixing chamber may be made small and relatively portable; figure 1 and 3-4) including an oxygen sensor configured to measure the concentration of oxygen in the inhaled gas ([0025] In some embodiments, the one or more O2 concentration sensors 45 is configured to output signals related to O2 concentration in the inhaled gas; figure 3-4) and carbon dioxide sensor configured to measure the concentration of carbon dioxide in the inhaled gas ([0025] In some embodiments, the one or more CO2 concentration sensors 47 is configured to output signals related to CO2 concentration in the inhaled gas. In some embodiments, CO2 sensors maybe nondispersive infrared (NDIR) CO2 sensors; figure 3-4).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the mixing chamber of Clemensen to implement an O2 sensor and a CO2 sensor at the mixing chamber in order to output signals related to O2 concentration and CO2- concentration in the inhaled gas, as taught by Vicario [0025].
Regarding claim 6, modified Clemensen discloses a system according to claim 5, further comprising a second mixing chamber (Clemensen: [0105] mixing chamber 134; figure 1) configured to receive a portion of the first gas via a connection with the inhalation limb and with the patient interface assembly ([0105] The humidified air/O2 mix flows into the patient 102 via one branch of the Y-piece attachment 106 and then back out through the second branch of the Y-piece attachment 106. The pressure of the expiration gas can be measured at the Y-piece attachment 106 via pressure line 132, or another place in the inspiratory limb of the circuit. The expired gas passes through an optional bacterial filter 130, and back through the ventilator 104 and out through the ventilator exit port 114. A small mixing chamber 134 may be attached to the ventilator exit port 114 and mixes the expired gas as it exits the ventilator 104; figure 1), the second mixing chamber comprising one or more of the second oxygen sensor and the third carbon dioxide sensor (As per the modification above, the mixing chamber 134 of Clemensen includes the O2 sensor and CO2 sensor).
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Clemensen et al. (US 20200359935 A1) as applied to claim 10 above, and further in view of Larsson et al. (WO 2023239285 A) and Brugnoli (US 20140235961 A1).
Regarding claim 11, Clemensen discloses a method according to claim 10, but is silent as to wherein further comprising:
receiving third carbon dioxide data indicative of a concentration of carbon dioxide in the second gas measured using a second carbon dioxide sensor located at the first sampling location;
comparing the second carbon dioxide data with the third carbon dioxide data; and
generating an alert responsive to determining that a difference between the second carbon dioxide data and the third carbon dioxide data exceeds a threshold level.
However, Larsson teaches an Oxygen Uptake Measurement Validation During Mechanical Ventilation (title) comprising:
receiving first carbon dioxide data close to the patient (The first gas analyser 103 is a capnometer arranged for mainstream (i.e. , non-diverting) capnography, meaning that it is configured to measure CO2 at the sample site. The first gas analyser 103 is typically positioned at or near the airway of the patient 3. For example, the first gas analyser 103 may be positioned in the common line 17 of the breathing circuit 9, in close proximity of the Y-piece 15. The first gas analyser 103 is configured to measure a fraction of CO2 at least in the expiration gases exhaled by the patient 3; figure 1; pg. 6; line 16-21);
receiving additional/secondary carbon dioxide data indicative of a concentration of carbon dioxide in exhaled gas measured using a second carbon dioxide sensor located at a mixing chamber (The system further comprises at least one second gas analyser 105. The at least one second gas analyser 105 is configured to measure both a fraction of CO2 and a fraction of 02 in expiration gases exhaled by the patient 3. The at least one second gas analyser 105 may be a single multigas analyser for measuring both CO2 and 02, or it may be two separate gas analysers for measuring CO2 and 02, respectively. In one example, the at least one second gas analyser 105 is a single gas analyser comprising a non-dispersive infrared (NDIR) CO2 sensor for CO2 measurements and a paramagnetic or electrochemical 02 sensor for 02 measurements. The at least one second gas analyser 105 is different than the first gas analyser 103. As will be discussed in more detail below, the at least one second gas analyser 105 may, for example, be arranged to measure CO2 and O2 in expiration gas that is mixed in a mixing chamber coupled to the expiratory line 13, or be a sidestream gas analyser that is arranged to sample expiration gases from, e.g., the common line 17; figure 1; pg. 6 line 24-35);
comparing the first carbon dioxide data with the additional carbon dioxide data (The control computer 27 is configured to determine, based on the CO2 measurements obtained by the first gas analyser 103, a first measure of carbon dioxide elimination of the patient 3…The control computer 27 is further configured to determine, based on the measurements obtained by the at least one second gas analyser 105, a second measure of CO2 elimination of the patient 3, as well as a measure of 02 uptake of the patient 3…The control computer 27 is further configured to validate or compensate the thus determined measure of 02 uptake based on a relation between the first and the second measures of CO2 elimination; pg. 7 line 13-24)
determining that a difference between the first carbon dioxide data with the additional carbon dioxide data exceeds a threshold level (The measure of 02 uptake (VO2miX; VO2Side) may be compensated when a deviation between the first (VCO2main) and the second (VCO2miX; VCO2Side) measures of CO2 elimination exceeds a maximum deviation threshold value; pg. 10 line 29-31).
Additionally, Brugnoli teaches a control unit configured to generate an alarm when a threshold level is exceeded ([0084] The electronic control unit 6 is prearranged for receiving signals 32a and 34a emitted by the aforesaid first humidity-sensing means 32 and second humidity-sensing means 34, for comparing the values of humidity measured, and for activating an alarm signal when the difference between the aforesaid values exceeds a pre-set threshold, indicating the need to replace the aforesaid tube with permeable wall defining the aforesaid sampling line 8. In particular, the alarm signal is activated when the concentration of water vapour in the flow of air within the sampling line 8 is higher than the concentration of the water vapour present in the external environment for a predetermined value).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the device of Clemensen to implement receiving additional/secondary carbon dioxide data indicative of a concentration of carbon dioxide in exhaled gas measured using a second carbon dioxide sensor located at a mixing chamber; comparing the first carbon dioxide exhaled data with the additional carbon dioxide data, and generating an alarm responsive to determining that a difference between the first carbon dioxide data with the additional carbon dioxide data exceeds a threshold level, in order to validate the data received, as taught by Larsson pg. 10 line 26-28, or generate an alarm to prompt an action from the operator when values are exceeded , as taught by Brugnoli [0084].
Claim(s) 12-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Clemensen et al. (US 20200359935 A1) as applied to claim 10 above, and further in view of Tham (US 20150182711 A1).
Regarding claim 12, Clemensen discloses a method according to claim 10, wherein determining a level of oxygen consumption, VO2, of the patient comprises using the formula
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38
235
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48
352
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(see equation 2 and equation 10 below. Examiner notes substituting V’E from equation 10 into equation 2 gives the second claimed formula)
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32
384
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Equation 2
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78
410
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Equation 10
, wherein FiO2 is a concentration of oxygen in the first gas ([0107] inspired oxygen concentration FIO2), FiCO2 is a concentration of carbon dioxide in the first gas ([0027] FICO2 Average inspiratory CO2 concentration (fractional)), FeO2 is a concentration of oxygen in the second gas ([0107] expired oxygen concentration FEO2), FeCO2 is a concentration of carbon dioxide in the second gas ([0022] FECO2 Mixed expired (average) CO2 concentration (fractional)), Vexh is the average flow rate of the second gas at the point of measurement of the concentration of oxygen in the second gas ([0074] V′E Expiratory minute ventilation. [0118] Oxygen consumption is calculated using the equations below. Components are average values, appropriately adjusted for the inspiration-expiration (I-E) delay time. Examiner notes that since the components used to calculate V’E are average values, the calculated V’E is an average value), and Vinh is the average flow rate of the first gas ([0077] V′I Inspiratory minute ventilation. [0129] Inspiratory minute ventilation V′I is determined by integration of inspiratory flow over one or more complete breaths. [0118] Oxygen consumption is calculated using the equations below. Components are average values, appropriately adjusted for the inspiration-expiration (I-E) delay time. Examiner notes that since the components used to calculate V’I are average values, the calculated V’I is an average value), wherein VCO2 is a value of carbon dioxide production determined using the second carbon dioxide data ([0109] By combining FIO2 and FICO2 (which is generally close to zero) with time shifted FEO2 and FECO2 it is possible to determine V′E, V′O2, V′CO2, as well as derived parameters including respiratory quotient (RQ)3 and resting energy expenditure (REE) of the patient), but is silent as to and wherein FeCO2 is determined using the formula
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32
84
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.
However, Tham teaches [0022] calculating gas exchange in a system wherein FeCO2 is determined using the formula
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32
84
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([0023] First considering the gas exchange in the lungs; inspired gases breathed into the lungs equal expired gases breathed out of the lungs plus gas entering or leaving the lungs from pulmonary blood. Applying conservation of mass to CO2 exchange over a breath;
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52
270
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[0024] or VT X FiCO2=VT X FeCO2+VCO2, where VT is the tidal volume per breath (in mL/min), FiCO2 is the averaged inspired CO2 concentration, and VCO2 is the CO2 production (in mL/min), in other words, CO2 from the pulmonary blood. The product of tidal volume (VT) and respiratory rate per minutes yield minute ventilation
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43
331
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).
Clemensen teaches [0109] FICO2 (which is generally close to zero).
Examiner notes that one of ordinary skill in the art would recognize that Vt is equal to Vexh + Vinh. Thus the formula is FeCO2 = VCO2/( Vexh + Vinh)
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the device of Clemensen to implement determining FeCO2 using the formula taught by Tham and the teachings of Clemensen in order to calculate FeCO2 without the use of complex formulas and using knowledge of one of ordinary skill in the art.
Regarding claim 13, modified Clemensen teaches a method according to claim 12, Clemensen teaches wherein each of the variables Vexh ([0118] Oxygen consumption is calculated using the equations below. Components are average values, appropriately adjusted for the inspiration-expiration (I-E) delay time. Examiner notes that since the components used to calculate V’e are average values, the calculated V’e is an average value),FiO2 ([0028] FIO2 Average inspiratory O2 concentration (fractional)), Fe02, FiCO2 ([0027] FICO2 Average inspiratory CO2 concentration (fractional)) and FeCO2 ([0022] FECO2 Mixed expired (average) CO2 concentration (fractional)) represents an average value over a defined time period ([0102] it is possible to determine both inspired volume flow and average FIO2 accurately and make the measurement relatively insensitive to fluctuations in FIO2 from the ventilator. Expired concentrations are measured at the exhaust port of the ventilator to obtain reliable average estimates. By combining inspired flow and FIO2 with time shifted FEO2 and FECO2, it is possible to determine expired flow, V′O2, V′CO2, RQ, and REE. [0113] Since gas concentration from a ventilator is not steady and fluctuates a great deal the inspired average concentration is determined, rather than simply the instantaneous concentration. As gas flow and concentrations both change over time, a simple arithmetic mean is insufficient for accuracy; the system uses a flow-weighted average to take the flow into account. [0118] Oxygen consumption is calculated using the equations below. Components are average values, appropriately adjusted for the inspiration-expiration (I-E) delay time).
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Clemensen et al. (US 20200359935 A1) as applied to claim 10 above, and further in view of Brix et al. (US 20140336523 A1).
Regarding claim 14, Clemensen discloses a method according to claim 10, but is silent as to wherein first carbon dioxide data comprises an ambient carbon dioxide concentration.
However, Brix teaches a computer-implemented method for determining a level of oxygen consumption of a patient (Estimation of Energy Expenditure; title; figure 1-5) wherein carbon dioxide data indicative of a concentration of carbon dioxide of an inhaled gas comprises an ambient carbon dioxide concentration ([0016] The method preferably further comprises estimating an inspiratory carbon dioxide concentration based on a known concentration of carbon dioxide in medical air. the inspiratory carbon dioxide concentration is so small that it is difficult to measure reliably. The inventors have discovered that the patient's energy expenditure can be estimated reliably, without measuring the inspiratory carbon dioxide concentration, based upon an estimate of the inspiratory carbon dioxide concentration. By way of explanation, the inspiratory gas 12 usually comprises medical air mixed with oxygen in a known ratio; that is, in addition to the oxygen that is already present in the medical air, the inspiratory gas 12 comprises a known amount of supplementary oxygen. The concentration of carbon dioxide in medical air is known a priori. For example, the medical dry air that is commonly found in hospitals and provided to the patient 2 by the ventilator 4 typically has a carbon dioxide concentration of 0.039%. Thus, it is possible to calculate the inspiratory carbon dioxide concentration based upon an inspiratory oxygen concentration measurement, the known ratio between medical air and supplementary oxygen in the inspiratory gas 12, and the known concentration of carbon dioxide in medial air. The processing means 7 is preferably operable to calculate the inspiratory carbon dioxide concentration as a function of the inspiratory oxygen concentration that is measured by the ventilator 4. For example, when the carbon dioxide concentration is assumed to be 0.039%, the inspiratory carbon dioxide concentration can be calculated using the following equation:
FiCO2=0.039.times.(120.95-FiO2) (4)
[0051] The resulting estimate of the inspiratory carbon dioxide concentration can be used as the value for FI.sub.CO2 in equation (1). This advantageously avoids the need for a sensor to measure the inspiratory carbon dioxide concentration. Furthermore, this also avoids the error in the estimate of the patient's energy expenditure that would result from the inherent inaccuracy of measuring the inspiratory carbon dioxide concentration directly).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the first carbon dioxide data to be estimated using a known concentration of medical air found in hospitals (ambient air) in order to avoid inaccuracy from measuring the inspiratory carbon dioxide concentration directly, as taught by Brix [0051].
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Mautin I Ashimiu whose telephone number is (571)272-0760. The examiner can normally be reached Monday - Friday, 7:30 a.m. - 4:30 p.m. ET.
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/M.I.A./Examiner, Art Unit 3785
/VALERIE L WOODWARD/Primary Examiner, Art Unit 3785