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 .
Response to Arguments
Applicant's arguments filed 06/18/2026 have been fully considered but they are not persuasive. Applicant argues claim 1 has been amended to incorporate the feature of fusing data from multiple devices and input variables combined with supplemental inputs provided by medical staff to generate a prediction of the condition of the vascular access, particularly where the supplemental inputs consider the date of creation of the vascular access or the date of a prior vascular access revision in characterizing the condition of the vascular access. Applicant argues Varasani ‘525 does not characterize vascular access but instead measures the hematocrit level of blood to generate an indication of vascular access recirculation. Applicant argues the system [of Varasani] determines a change in blood volume of a patient over time based on the measured hematocrit level and generates therefrom an indication of vascular access recirculation. Applicant argues Varasani ‘525 does not appear to characterize the vascular access of a dialysis patient and particularly does not disclose considering the date of creation of the vascular access or the date of a prior vascular access revision in characterizing a vascular access. The examiner respectfully disagrees. Varasani teaches a system that monitors vascular access recirculation by using a hematocrit-based value to measure how concentrated the blood is in the bloodlines – arterial and/or venous. The system of Varasani estimates the patient’s blood volume over time, determines a threshold blood volume reduction over time for the patient, compares the change in blood volume of the patient over time to the threshold blood volume reduction over time, and based on the comparison, generates an indication, i.e. characterizes vascular access recirculation (Fig. 3; paras. 0004-0006). The system of Varasani also fuses data from multiple devices (i.e. hematocrit sensor, arterial pressure sensor, air sensor, inflow pressure sensor; paras. 0022-0023) and input variables (i.e. blood temperature, body size of the patient; paras. 0016, 0030), combined with supplemental input from medical staff to generate an indication of vascular access recirculation (para. 0026) – where Varasani teaches the difference threshold is programmable by a clinician via a user interface of the hemodialysis device or via a computing device (para. 0028). Varasani teaches the blood volume is observed over time during the dialysis session (para. 0031). The session obviously includes a date, either a creation date and/or a previous date from a prior session for subsequent treatments. Thus, the system of Varasani provides the claimed system and the method incorporating further data including a date would be obvious to the operation of the system.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-3, 6, 7, and 15-17 are rejected under 35 U.S.C. 103 as being unpatentable over Varasani US Patent Application Publication 2023/0013525.
As to claim 1, Varasani teaches a method for automatically characterizing a vascular access of a dialysis patient who is or was connected to a dialysis machine, the method comprising the steps of:
determining a recirculation rate (para. 0004, 0013);
characterizing the vascular access based on the recirculation rate (para. 0004, 0013) – where Varasani teaches the processing circuitry of the hemodialysis system is configured to determine a change in the blood volume of a patient over time based on a signal generated by a hematocrit sensor, compare the change in blood volume over time with a threshold blood volume reduction over time, and determine whether there is vascular access recirculation based on the comparison (para. 0004), by means of the dialysis machine or by means of another measuring device where Varasani teaches the hemodialysis device 12 may be communicatively coupled one or more external sensors, such as one or more sensors 18, via a link 20 (para. 0023).
Varasani teaches the threshold amount of vascular access recirculation may be programmable by a clinician (para. 0035). The clinician or patient may receive notification via a user interface or communication circuitry of hemodialysis device 12 to a computing device 30, which may be a visual, audible, or tactile notification to adjust a which may be attached to arterial line 16 or venous line 14 needle (indicating vascular access), a notification to change a catheter that may be attached to either line, or a notification to pause dialysis treatment, and indication of the amount of vascular access recirculation, or the like (para. 0036, 0059).
Varasani teaches transmitting the determined recirculation rate to a central processing unit 30 (Fig. 1-2; para 0026-0028);
transmitting further data (from sensor 18) characteristic of a quality of the vascular access to the central processing unit 30 (para. 0028, 0031), and
characterizing the vascular access with the central processing unit based on the recirculation rate and the further data – where Varasani teaches the blood volume may be indicative of vascular access recirculation (para. 0031).
Varasani teaches further data include the body size, body weight, body mass index may is relative to blood volume, such that a larger patient may have a higher blood volume than a smaller body size (para. 0030). Varasani teaches the hemodialysis device 12 or another device stores the threshold blood volume and patient data (body weight, blood pressure) and determines the threshold blood volume reduction by reading the value from memory (para. 0030, 0055, 0061). Varasani teaches the blood volume is observed over time during the dialysis session (para. 0031). The session obviously includes a date, either a creation date and/or a previous date from a prior session for subsequent treatments where Varasani teaches in some examples the hemodialysis device stores in memory a treatment program for a patient, and if the hemodialysis device is used to treat more than one patient, the hemodialysis device may store multiple treatment programs such that each patient may have an associated personalized treatment program (0045). It would have been obvious to one having ordinary skill in the art to provide a data set which includes a creation date and a date of a prior vascular access revision associated with each patient session to develop a personalized treatment program for subsequent sessions.
As to claim 2, the vascular access is characterized as having a decreasing quality as the recirculation rate increases – where Varasani teaches while some degree of vascular access recirculation may be expected in hemodialysis treatment, a higher degree of vascular access recirculation may be indicative of a relatively ineffective hemodialysis treatment session (para. 0013)
As to claim 3, The method according to claim 1, wherein: the recirculation rate is determined quantitatively or qualitatively by (para. 0032):
changing at least one operational parameter of the dialysis machine – a clinician may prescribe a certain blood flow rate (para. 0038);
measuring a change in at least one blood value at an arterial access of the dialysis machine – measuring transit time for blood from when blood enters arterial line 16 to when blood exits venous line 14 (Fig. 1; para. 0038); and
determining the recirculation rate dependent on the change in the at least one blood value at the arterial access of the dialysis machine - where Varasani teaches using the transit time and a predetermined period of time to determine recirculation rate (para. 0039, 0059).
As to claim 6, the at least one operational parameter of the dialysis machine influences an ultrafiltration rate – where Varasani teaches after the predetermined period of time, hemodialysis device may return the ultrafiltration rate to the original programmed ultrafiltration rate, or may prevent or refrain from increasing the ultrafiltration rate a second time for at least another predetermined period of time (para. 0040); and the at least one blood value contains a hematocrit value (Varasani 0033).
As to claim 7, the ultrafiltration rate is increased, and the recirculation rate is determined dependent on an increase in the hematocrit value (Abstract, para. 0033).
As to claim 15, the recirculation rate and the further data are evaluated by machine learning for characterizing the vascular access - where Varasani teaches the processing circuitry 116 may determine a threshold blood volume reduction over time for patient 10 based on a body size of the patient or read the threshold blood volume reduction from thresholds 122 in memory 118(para. 0055, 0061).
As to claim 16, an alert is output dependent on a characterization of the vascular access (para. 0035-0036).
As to claim 17, Varasani teaches a system for automatically characterizing a vascular access of a dialysis patient who is or was connected to a dialysis machine, comprising: the dialysis machine 12/112; and a central processing unit (Fig. 2; para. 0042), the dialysis machine 12/112 and the central processing unit being designed to carry out a method according to claim 1 (para. 0042-0047).
Claims 4, 5, 8, 9, and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Varasani US 2023/0013525 (herein known as Varasani ‘525) in view of Varasani US Patent Application Publication 2023/0018668 (herein known as Varasani ‘668).
As to claim 4, Varasani ‘525 teaches the present invention substantially as claimed. Varasani ‘525 does not specifically teach the recirculation rate is determined as having greater values as the change (in the operational parameter) increases. Varasani ‘668 teaches a hemodialysis device that is configured to determine that sensed parameters of interest indicate that a change in hemodialysis treatment parameters should be made (‘668 para. 0018). Varasani ‘668 teaches the one or more sensors are configured to sense one or more parameters of interest such as blood pressure, heart rate, blood volume change, and the like (‘668 para. 0018). Varasani teaches the treatment parameters may include sodium concentration of a dialysis solution, an ultrafiltration rate, and ultrafiltration volume, a duration of a hemodialysis session, temperature of filtration, and the like (“668 para. 0019). Varasani ‘668 teaches stored associations between parameters of interest and treatment parameters may be used, by the hemodialysis device, for example, to automatically change any of the hemodialysis treatment parameters based on one or more events occurring involving any of the parameters of interest (‘668 para. 0020, 0040). Varasani ‘668 teaches an example of an investigatory action is measuring systemic blood pressure in response to determining a reduction in blood volume reaches a predetermined threshold value. Although Varasani ‘525 does not specifically teach the recirculation rate is determined as having greater values as the change (in the operational parameter) increases, it would have been obvious to one having ordinary skill in the art before the invention was originally filed to take corrective action by adjusting an operational parameter to increase the recirculation rate as taught in Varasani ‘668 (para. 0086) and to improve the efficacy of the hemodialysis treatment (Varasani ‘668 para. 0016).
As to claim 5, the at least one operational parameter influences a change of a dialysate flow through a dialyzer of the dialysis machine (Varasani ‘668 para. 0086).
As to claim 8, the at least one operational parameter influences a change in the temperature of outflowing blood at a venous access of the dialysis machine, and the at least one blood value contains a temperature of blood flowing through the arterial access of the dialysis machine – where Varasani ‘668 teaches adjusting the dialysate temperature (operational parameter) in response to a blood temperature not being within an expected predetermined temperature range (Varasani ‘668 para. 0047), thereby taking corrective action to adjust or increase the blood temperature to meet the predetermined range.
As to claim 9, the at least one operational parameter influences a temperature of a dialysis fluid, and the at least one blood value contains a temperature of blood flowing through the arterial access of the dialysis machine – where Varasani ‘668 teaches adjusting the dialysate temperature in response to a blood temperature not being within an expected predetermined temperature range (Varasani ‘668 para. 0047).
As to claim 12, the recirculation rate is ascertained quantitatively or qualitatively based on a comparison between a measured clearance and a nominal clearance for the dialysis machine (Varasani ‘668 para. 0043).
Claims 10 and 11 are rejected under 35 U.S.C. 103 as being unpatentable Varasani US Patent Application Publication 2023/0013525 in view of Cole et al. USPN 6189388.
As to claims 10 and 11, Varasani teaches the present invention substantially as claimed. Varasani does not teach the at least one operational parameter influences an addition of a substance into outflowing blood at the venous access of the dialysis machine, and the at least one blood value contains a concentration of the substance in the blood flowing through an arterial access of the dialysis machine. Cole teaches a system and method of detecting blood flow in a fistula by comparing the property of blood entering the fistula to the property of bleed being withdrawn from the fistula. Cole teaches a method of quantitatively determining the degree of recirculation in a fistula is using a bolus of marker fluid having a conductivity different from that of blood that is injected through an injection site in the outlet line. Cole teaches a differential conductivity monitor quantitatively measures the degree of recirculation in a fistula by comparing the conductivity of blood entering the fistula to the conductivity of blood being withdrawn from the fistula. This measurement is made as blood flows in the predominant direction from artery to vein. Cole teaches other fluid properties utilized for the measurement of recirculated blood are temperature of the fluid and speed of conduction of sound, and some of these measurement techniques also involve injection of a bolus of marker material into the blood flow (Cole col. 1, line 60 through col. 2, line 10). It would have been obvious to one having ordinary skill in the art before the invention was originally filed to have substituted the method taught in Cole since this method performs the same function of providing a method of determining the degree of recirculation in a fistula during dialysis. See MPEP 2143.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JACQUELINE F STEPHENS whose telephone number is (571)272-4937. The examiner can normally be reached 8:30-5:00.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sarah Al-Hashimi can be reached at 571-272-7159. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JACQUELINE F STEPHENS/ Primary Examiner, Art Unit 3781
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