(101 days)
The NxStage System One is indicated for the treatment of acute and chronic renal failure, or fluid overload using hemofiltration, hemodialysis, and/or ultrafiltration, in an acute or chronic care facility.
The System is also indicated for home hemodialysis, including home nocturnal hemodialysis.
All treatments must be administered under physician's prescription, and must be performed by a trained and qualified person, considered to be competent in the use of this device by the prescribing physician.
The NxStage System One is comprised of the NxStage Cycler, an electromechanical control unit; the NxStage Cartridge, a sterile, single-use extracorporeal blood and fluid management circuit (with or without a preattached high permeability filter) that mounts integrally within the NxStage Cycler. The combined system is designed to deliver hemofiltration, hemodialysis and/or ultrafiltration in an acute or chronic care facility. The NxStage System One is also indicated for home hemodialysis, including home nocturnal hemodialysis.
This document is a 510(k) Premarket Notification for the NxStage System One, a high permeability hemodialysis system. It seeks to demonstrate substantial equivalence to a previously cleared predicate device (K141752).
Based on the provided document, here's an analysis regarding acceptance criteria and supporting studies:
1. Table of Acceptance Criteria and Reported Device Performance
The document presents a comparison of technological characteristics between the proposed device and the predicate device in Table 1. However, this table does not directly state acceptance criteria in terms of performance metrics (e.g., minimum accuracy, maximum allowable deviation) against which the proposed device was tested. Instead, it states that the "Proposed Device (NxStage System One)" is "Same" for most parameters compared to the "Predicate Device (NxStage System One)".
The closest the document comes to defining acceptance criteria is under "Effluent Volume Accuracy" for the predicate device, where specifications for different software versions are provided. However, it only states that the proposed device is "Same," implying it meets these same specifications without explicitly presenting the proposed device's performance against them.
Therefore, a table of acceptance criteria and reported device performance cannot be fully constructed from the provided text as the explicit acceptance criteria and quantitative performance results for the proposed device are not detailed, beyond stating they were "met."
Inference of Acceptance Criteria (from Predicate Device Specifications as implied by "Same"):
| Parameter | Acceptance Criteria (from Predicate) | Reported Device Performance (Implied) |
|---|---|---|
| Flow Rates: Blood | 10-600 ml/min | Same (Implied to meet 10-600 ml/min) |
| Flow Rates: Prescription Fluid /Dialysate | 0-18000 ml/hr | Same (Implied to meet 0-18000 ml/hr) |
| Flow Rates: Ultrafiltration | 0-2400 ml/hr | Same (Implied to meet 0-2400 ml/hr) |
| Transmembrane Pressure | Yes (Implies capability) | Same (Implied to have capability) |
| Monitoring: Venous Pressure | 0 to 400 mmHg | Same (Implied to monitor 0 to 400 mmHg) |
| Monitoring: Effluent Fluid Pressure | 0 to 500 mmHg | Same (Implied to monitor 0 to 500 mmHg) |
| Monitoring: Air Detector | Reduction of detector signal lasting 6 ms minimum (Approximates a 60 microliter bubble at 400 mmHg venous pressure and 600 ml/min blood flow) | Same (Implied to meet this specification) |
| Monitoring: Blood Leak Detector | 15% reduction in detector signal lasting 20 seconds minimum. Signal reduction % based on a 0.35 ml/min leak rate of 32 Hct blood. | Same (Implied to meet this specification) |
| Effluent Volume Accuracy (Software versions 4.7 and below) | Greater of 300 ml/12 hr or 3% of exchange volume | Same (Implied to meet this specification) |
| Effluent Volume Accuracy (Software versions 4.8 and higher) | Therapy Fluid Flow Rate (L/hr) > 3 ml/hr: +100 or +5% UF; ≤ 3 ml/hr: +25 ml/hr* (*Representing 95/90 tolerance interval established under controlled laboratory testing conditions) | Same (Implied to meet this specification) |
| IV Prescription Fluid | Off-line, sterile- physician prescribed, indicated for infusion | Same (Implied to handle this type) |
| Dialysate | Available as pre-packaged pre-mixed sterile fluids or via the PureFlow SL | Same (Implied to be compatible with these types) |
| Compatible Blood Tubing Set | NxStage Standard Cartridge | Same (Implied to be compatible) |
| Software | Software version 4.10 | Same (Implied to use or be compatible with 4.10) |
2. Sample Size Used for the Test Set and Data Provenance
The document states: "No Clinical testing was conducted." All testing mentioned is "Non-Clinical Test/Performance Testing - Bench."
- Sample Size: Not explicitly stated for bench testing. The document refers to "Simulated treatments" but does not give a number of simulations or samples used.
- Data Provenance: Not applicable as no clinical data was used. All testing appears to be in-house bench testing.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
Not applicable. Since no clinical testing was conducted and all testing was "Non-Clinical Test/Performance Testing - Bench," there was no need for expert ground truth establishment in a clinical context. The "ground truth" for bench testing would be established by the engineering specifications and validated test methods.
4. Adjudication Method for the Test Set
Not applicable, as no clinical testing with human subjects or expert review was performed.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of How Much Human Readers Improve with AI vs Without AI Assistance
Not applicable. This is a 510(k) for a medical device (hemodialysis system), not an AI-powered diagnostic or interpretive device that would involve human readers.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) Was Done
Not applicable in the context of an "algorithm only" performance that would typically compare to human clinicians. This device is a treatment system. The "Non-Clinical Test/Performance Testing - Bench" can be considered a form of standalone performance assessment against engineering specifications, but it's not "algorithm only" in the sense of a software-as-a-medical-device (SaMD) context. It's the performance of the integrated electromechanical control unit with its software and cartridge.
7. The Type of Ground Truth Used
For the non-clinical bench testing, the "ground truth" would be established by:
- Engineering specifications and design requirements: The device's performance was measured against these predefined technical standards and parameters (e.g., flow rates, pressure monitoring ranges, accuracy for effluent volume).
- Physical measurements and simulated conditions: The testing simulates treatment conditions and measures the device's output against expected physical and chemical outcomes.
8. The Sample Size for the Training Set
Not applicable. This device is not an AI/ML model that requires a "training set" in the conventional sense. The "training" for a traditional medical device involves its design, development, and iterative testing/refinement against engineering principles and specifications.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no "training set" for an AI/ML model. The "ground truth" for the device's design and development (analogous to a training process for an AI) comes from established medical standards for hemodialysis, regulatory requirements, risk analysis, and engineering principles.
§ 876.5860 High permeability hemodialysis system.
(a)
Identification. A high permeability hemodialysis system is a device intended for use as an artificial kidney system for the treatment of patients with renal failure, fluid overload, or toxemic conditions by performing such therapies as hemodialysis, hemofiltration, hemoconcentration, and hemodiafiltration. Using a hemodialyzer with a semipermeable membrane that is more permeable to water than the semipermeable membrane of the conventional hemodialysis system (§ 876.5820), the high permeability hemodialysis system removes toxins or excess fluid from the patient's blood using the principles of convection (via a high ultrafiltration rate) and/or diffusion (via a concentration gradient in dialysate). During treatment, blood is circulated from the patient through the hemodialyzer's blood compartment, while the dialysate solution flows countercurrent through the dialysate compartment. In this process, toxins and/or fluid are transferred across the membrane from the blood to the dialysate compartment. The hemodialysis delivery machine controls and monitors the parameters related to this processing, including the rate at which blood and dialysate are pumped through the system, and the rate at which fluid is removed from the patient. The high permeability hemodialysis system consists of the following devices:(1) The hemodialyzer consists of a semipermeable membrane with an in vitro ultrafiltration coefficient (K
uf ) greater than 8 milliliters per hour per conventional millimeter of mercury, as measured with bovine or expired human blood, and is used with either an automated ultrafiltration controller or anther method of ultrafiltration control to prevent fluid imbalance.(2) The hemodialysis delivery machine is similar to the extracorporeal blood system and dialysate delivery system of the hemodialysis system and accessories (§ 876.5820), with the addition of an ultrafiltration controller and mechanisms that monitor and/or control such parameters as fluid balance, dialysate composition, and patient treatment parameters (e.g., blood pressure, hematocrit, urea, etc.).
(3) The high permeability hemodialysis system accessories include, but are not limited to, tubing lines and various treatment related monitors (e.g., dialysate pH, blood pressure, hematocrit, and blood recirculation monitors).
(b)
Classification. Class II. The special controls for this device are FDA's:(1) “Use of International Standard ISO 10993 ‘Biological Evaluation of Medical Device—Part I: Evaluation and Testing,’ ”
(2) “Guidance for the Content of 510(k)s for Conventional and High Permeability Hemodialyzers,”
(3) “Guidance for Industry and CDRH Reviewers on the Content of Premarket Notifications for Hemodialysis Delivery Systems,”
(4) “Guidance for the Content of Premarket Notifications for Water Purification Components and Systems for Hemodialysis,” and
(5) “Guidance for Hemodialyzer Reuse Labeling.”