The NxStage PureFlow SL module is an optional accessory to the NxStage System One™ that prepares dialysate for use during hemodialysis, as prescribed by the physician.

Device Description

The NxStage PureFlow SL module is an optional accessory to the NxStage System One used to prepare water for hemodialysis that meets ANSI/AAMI/ISO 13959:2009 and proportion it with dialysate concentrate to produce dialysate per ANSI/AAMI/ISO 11663:2009. The PureFlow SL consists of the Control Unit (CU), the water Pre-Treatment Unit, the optional OPTA Kit, the Purification Pack (PAK), and the Dialysate Sack (SAK) with Dialysate Concentrate.

AI/ML Overview

Here's an analysis of the provided text regarding acceptance criteria and the supporting study:

The provided document is a 510(k) Summary for a device modification, not a comprehensive study report with detailed performance data. Therefore, many of the requested details about specific acceptance criteria, study sizes, ground truth establishment, and MRMC effectiveness are not explicitly stated. The document focuses on demonstrating substantial equivalence to a predicate device based on design control requirements and general performance verification.

Here's a breakdown of the available information structured as requested:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not provide a table with specific quantitative acceptance criteria or detailed numerical performance results. Instead, it makes a general statement about meeting design specifications and being suitable for its intended use.

However, based on the Technological Characteristics Comparison Table (Table 1) and the description, we can infer some qualitative "acceptance criteria" through comparison with the predicate device and relevant standards:

Feature/Criteria (Inferred)	Reported Device Performance
Indication for Use	Same as predicate device (NxStage PureFlow SL module is an optional accessory to the NxStage System One that prepares dialysate for use during hemodialysis, as prescribed by the physician).
Water purification technology	Same as predicate device (Deionization).
Ultrafiltration	Same as predicate device (Redundant ultrafiltration replaced within 12 weeks).
Water Quality	Meets or exceeds requirements per ANSI/AAMI/ISO 26722:2009 (Water treatment equipment for hemodialysis applications).
Proportioning method	Same as predicate device (Mixed to use Batch via volumetric dosing of purified water with specified amount of electrolyte concentrate).
Conductivity Measurement	Same as predicate device (System measures final batch conductivity prior to each treatment per ANSI/AAMI/ISO 26722:2009).
Dialysate Concentrate	Same as predicate device (Standard hemodialysis concentrate per ANSI/AAMI/ISO 13958:2009).
Packaging	Same as predicate device (Packaged in flexible LLDPE bags with standard luer lock connector, ranging in size from 20L to 60L).
Buffer	Same as predicate device (Lactate).
Mix-to-Use Time	Same as predicate device (96-hours).
Bioburden	Same as predicate device (AAMI/ANSI/ISO 11663: <100 CFU/ml).
Endotoxin	Same as predicate device (AAMI/ANSI/ISO 11663: <0.5 EU/ml).
Batch size	Same as predicate device (Range – 20 to 60 L; 40, 50 and 60L currently available).
Fluid warming Method	Same as predicate device (Integrated fluid warming pad).
Validation of Design Control Requirements	Certification of compliance to 21 CFR §820.30 Design Control Requirements.
General Performance	Predetermined acceptance criteria were met. Device is suitable for labeled indications for use.

2. Sample Size Used for the Test Set and Data Provenance

Sample Size for Test Set: Not specified. The document states "Performance, verification and validation testing was conducted," but no specific sample sizes for this testing are provided.
Data Provenance: Not specified. The testing is referred to as "Non-Clinical Test/Performance Testing - Bench," implying internal lab testing, but no country of origin or whether it was retrospective or prospective is mentioned.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

Not applicable/Not specified. This is a device modification for a hemodialysis system, not an imaging or diagnostic AI device where expert reads establish ground truth. The "ground truth" for this type of device relates to its adherence to engineering specifications and performance standards.

4. Adjudication Method for the Test Set

Not applicable/Not specified. Since expert consensus on ground truth is not relevant here, no adjudication method would be mentioned.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

Not applicable. This device is a component of a hemodialysis system and does not involve AI or human readers for diagnostic interpretation.

6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done

Not applicable in the context of an AI algorithm. The device's performance is inherently "standalone" in its function of preparing dialysate, but this is mechanical/chemical performance, not AI.

7. The Type of Ground Truth Used

The "ground truth" for this device's performance relies on engineering specifications, design control requirements, and compliance with established industry standards (e.g., ANSI/AAMI/ISO 13959:2009, ANSI/AAMI/ISO 11663:2009, ANSI/AAMI/ISO 26722:2009, ANSI/AAMI/ISO 13958:2009). The device's performance against these standards constitutes its "ground truth."

8. The Sample Size for the Training Set

Not applicable. This device is not an AI/ML device that requires a training set.

9. How the Ground Truth for the Training Set was Established

Not applicable, as there is no training set for this type of device.

Study Proving Device Meets Acceptance Criteria:

The study proving the device meets acceptance criteria is described as "Performance, verification and validation testing" (Section F). This testing was conducted to characterize the performance of the modified device. The submission states that "predetermined acceptance criteria were met. Results of this testing have documented that the proposed NxStage PureFlow SL is substantially equivalent to the predicate device and is suitable for the labeled indications for use."

The entire submission is a "Special 510(k) Device Modification" which means the focus is on certifying compliance to 21 CFR §820.30 Design Control Requirements and demonstrating that the modifications do not alter the safely and effectiveness, making it substantially equivalent to the cleared predicate device (K111174). The study is essentially the internal design verification and validation activities conducted by NxStage Medical, Inc.

Summary

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This 510(k) Summary is being submitted in accordance with the requirements of the Safe Medical Device Act (SMDA) of 1990. The content contained in this 510(k) summary has been provided in conformance with 21 CFR §807.92.

A. Submitter's Information: March 5, 2014 Date Name: NxStage Medical, Inc. 350 Merrimack Street Address: Lawrence, MA 01843 FDA Establishment 9045797 Owner/Operator Number: Contact Person: Mary Lou Stroumbos Director, Regulatory Affairs Phone: (978) 687-4872 Fax: (978) 687-4750 MEDIMEXICO, S. DE R.L. DE C.V. Manufacturer: Av. Valle imperial No. 10523 Parque industrial Valle Sur Tijuana, B.C., Mexico 22180

FDA Establishment Registration Number:

9616074

Sterilization Site:

Steris Isomedix, Inc. 1000 S. Sarah Place Ontario, CA 91761

Contract Sterilizer

510(k) Device Modification NxStage Medical, Inc.

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B. Device Name:
Trade/Proprietary Name:	NxStage PureFlow SL
Common/Usual Name:	Subsystem, proportioning
Classification Name:	Hemodialysis systems and accessories
Regulation Number:	21 CFR 876.5820
Product Code:	78 FKR
Device Classification:	Class II
Device Panel:	Gastroenterology-Urology (GU)/Gastro-Renal (GRDB)

C. Substantial Equivalence:

This submission is a Special 510(k) Device Modification as described in the FDA's Guidance document entitled, "The New 510(k) Paradigm - Alternate Approaches to Demonstrating Substantial Equivalence in Premarket Notifications." In support of this Special 510(k), NxStage has provided certification of compliance to 21 CFR §820.30 Design Control Requirements. Design validation testing was performed to ensure that the NxStage PureFlow SL (PFSL) module with modifications meets design specifications. The NxStage PFSL module with modifications has been compared to the legally marketed predicate device as cleared through K111174 (September 19, 2011) and was found to be substantially equivalent.

D. Device Description/Indications for Use:

510(k) Device Modification NxStage Medical, Inc.

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Indications for use:

The NxStage PureFlow SL module is an optional accessory to the NxStage System One that prepares dialysate for use during hemodialysis, as prescribed by the physician.

E. Technological Characteristics:

The proposed device has the same technological characteristics and is similar in design and configuration as compared to the predicate device.

Table 1Device Technological Characteristics Comparison Table
Feature	ProposedNxStage PFSL Module(subject of this 510(k))	NxStage PFSL Module(K111174)
Indication for Use	Same	The NxStage PureFlow SLmodule is an optional accessoryto the NxStage System One thatprepares dialysate for use duringhemodialysis, as prescribed bythe physician.
Water Purification
Water purificationtechnology	Same	Deionization
Ultrafiltration	Same	Redundant ultrafiltration replacedwithin 12- weeks
Water Quality	Same	Meets or exceeds requirementsper ANSI/AAMI/ISO 26722:2009Water treatment equipment forhemodialysis applications
Dialysate Proportioning :
Proportioningmethod	Same	Mixed to use Batch viavolumetric dosing of purifiedwater with specified amount ofelectrolyte concentrate
Table 1Device Technological Characteristics Comparison Table
Feature	ProposedNxStage PFSL Module(subject of this 510(k))	NxStage PFSL Module(K111174)
ConductivityMeasurement	Same	Yes - the System measures finalbatch conductivity prior to eachtreatment per ANSI/AAMI/ISO26722:2009
Concentrate
DialysateConcentrate	Same	Standard hemodialysisconcentrate per ANSI/AAMI/ISO13958:2009
Packaging	Same	Packaged in flexible LLDPEbags with standard luer lockconnector. Ranging in size from20L to 60L
Buffer	Same	Lactate
Point of Use Dialysate Quality
Mix-to-Use Time	Same	96-hours
Bioburden	Same	AAMI/ANSI/ISO 11663:<100 CFU/ml
Endotoxin	Same	AAMI/ANSI/ISO 11663:<0.5 EU/ml
Batch size	Same	Range – 20 to 60 L(40, 50 and 60L currentlyavailable)
Fluid warming
Method	Same	Integrated fluid warming pad

510(k) Device Modification NxStage Medical, Inc.

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NxStage Medical, Inc.

510(k) Device Modification
NxStage Medical, Inc.

Confidential

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F. Summary of Non-Clinical Test/Performance Testing - Bench NxStage believes that the information and data provided in this submission clearly describes the proposed device and demonstrates that the device is adequately designed for the labeled indications for use. Performance, verification and validation testing was conducted to characterize performance of the proposed device and the predetermined acceptance criteria were met. Results of this testing have documented that the proposed NxStage PureFlow SL is substantially equivalent to the predicate device and is suitable for the labeled indications for use.

510(k) Device Modification NxStage Medical, Inc.

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Public Health Service

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring MD 20993-0002

May 15, 2014

NxStage Medical, Inc. Mary Lou Stroumbos Director, Regulatory Affairs 350 Merrimack Street Lawrence, MA 01843

Re: K140571

Trade/Device Name: NxStage® PureFlow™ SL Regulation Number: 21 CFR§ 876.5820 Regulation Name: Hemodialysis system and accessories Regulatory Class: II. Product Code: FKR Dated: April 17, 2014 Received: April 18, 2014

Dear Mary Lou Stroumbos,

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRFI does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies.

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Page 2 - Mary Lou Stroumbos

You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to hup://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/McdicalDevices/Safety/ReportalProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.

Sincerely yours,

Herbert P. Lerner -S

for Beniamin R. Fisher, Ph.D. Director Division of Reproductive, Gastro-Renal, and Urological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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INDICATIONS FOR USE

510(k) Number (if known): K140571

NxStage® PureFlow™ SL Device Name:

The NxStage PureFlow SL module is an optional Indications for Use: accessory to the NxStage System One™ that prepares dialysate for use during hemodialysis, as

prescribed by the physician.

Prescription Use Use (Part 21 CFR 801 Subpart D) Over-The-Counter

(21 CFR 807 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

AND/OR

Concurrence of CDRH, Office of Device Evaluation (ODE)

Herbert P. Lerner-S
2014.05.15 15:31:51 -04'00'

Page 1 of 1

Page 20

. . . .

Regulation Number and Section

§ 876.5820 Hemodialysis system and accessories.

(a)
Identification. A hemodialysis system and accessories is a device that is used as an artificial kidney system for the treatment of patients with renal failure or toxemic conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and accessories. Blood from a patient flows through the tubing of the extracorporeal blood system and accessories to the blood compartment of the dialyzer, then returns through further tubing of the extracorporeal blood system to the patient. The dialyzer has two compartments that are separated by a semipermeable membrane. While the blood is in the blood compartment, undesirable substances in the blood pass through the semipermeable membrane into the dialysate in the dialysate compartment. The dialysate delivery system controls and monitors the dialysate circulating through the dialysate compartment of the dialyzer.(1) The extracorporeal blood system and accessories consists of tubing, pumps, pressure monitors, air foam or bubble detectors, and alarms to keep blood moving safely from the blood access device and accessories for hemodialysis (§ 876.5540) to the blood compartment of the dialyzer and back to the patient.
(2) The conventional dialyzer allows a transfer of water and solutes between the blood and the dialysate through the semipermeable membrane. The semipermeable membrane of the conventional dialyzer has a sufficiently low permeability to water that an ultrafiltration controller is not required to prevent excessive loss of water from the patient's blood. This conventional dialyzer does not include hemodialyzers with the disposable inserts (Kiil type) (§ 876.5830) or dialyzers of high permeability (§ 876.5860).
(3) The dialysate delivery system consists of mechanisms that monitor and control the temperature, conductivity, flow rate, and pressure of the dialysate and circulates dialysate through the dialysate compartment of the dialyzer. The dialysate delivery system includes the dialysate concentrate for hemodialysis (liquid or powder) and alarms to indicate abnormal dialysate conditions. This dialysate delivery system does not include the sorbent regenerated dialysate delivery system for hemodialysis (§ 876.5600), the dialysate delivery system of the peritoneal dialysis system and accessories (§ 876.5630), or the controlled dialysate delivery system of the high permeability hemodialysis system § 876.5860).
(4) Remote accessories to the hemodialysis system include the unpowered dialysis chair without a scale, the powered dialysis chair without a scale, the dialyzer holder set, dialysis tie gun and ties, and hemodialysis start/stop tray.
(b)
Classification. (1) Class II (performance standards) for hemodialysis systems and all accessories directly associated with the extracorporeal blood system and the dialysate delivery system.(2) Class I for other accessories of the hemodialysis system remote from the extracorporeal blood system and the dialysate delivery system, such as the unpowered dialysis chair, hemodialysis start/stop tray, dialyzer holder set, and dialysis tie gun and ties. The devices subject to this paragraph (b)(2) are exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 876.9.