(84 days)
The NxStage System One is indicated for treatment of renal failure or fluid overload using hemofiltration, hemodialysis, and/or ultrafiltration. All treatments must be administered by a health care provider, under physician's prescription.
The NxStage System One consists of the NxStage Cycler and the NxStage Cartridge Extracorporeal Blood and Fluid Circuit.
The NxStage Cycler is an electro-mechanical device that interfaces with the NxStage Cartridge. The NxStage Cartridge is a single-use extracorporeal blood circuit and fluid management device that mounts integrally within the NxStage Cycler. The NxStage Cartridge Express is a single-use extracorporeal blood circuit and fluid management device with a pre-attached high flux (permeability) hollow-fiber filter.
This is an interesting case where the provided document (a 510(k) summary for a medical device) doesn't contain a conventional study demonstrating the device meets specific performance acceptance criteria. Instead, it details a "Special 510(k) Device Modification" which relies on different evidence.
Here's a breakdown based on the provided text:
Acceptance Criteria and Device Performance
This document does not present a table of specific quantitative acceptance criteria (e.g., "filtration rate >= X L/hr") and corresponding reported device performance values. Instead, the "acceptance criteria" here is met through a "design control certification" and demonstration of "substantial equivalence" to a predicate device.
The overarching acceptance criterion is Substantial Equivalence to the predicate device (cleared in K032356). The device performance is deemed acceptable because it meets design specifications and the modified device (NxStage Cartridge Express) is found to be substantially equivalent to the baseline device (the predicate).
Study Details
Given this context of a "Special 510(k) Device Modification," many of the standard study questions for a new device's efficacy or diagnostic accuracy are not applicable in the usual sense.
1. Table of Acceptance Criteria and Reported Device Performance
As explained above, no such quantitative table is provided in this document. The "acceptance criteria" revolve around demonstrating design control compliance and substantial equivalence.
2. Sample Size for the Test Set and Data Provenance
- Sample Size for Test Set: Not explicitly mentioned as a distinct "test set" for performance evaluation in the traditional sense. The document refers to "Design validation testing," which implies testing was done, but the sample size of units/cartridges tested is not specified.
- Data Provenance: Not specified. It's implied to be internal testing by NxStage Medical, Inc.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
Not applicable. This is not a study requiring expert readers or ground truth establishment for diagnostic accuracy.
4. Adjudication Method for the Test Set
Not applicable. This is not a study requiring expert reader adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done
No, an MRMC comparative effectiveness study was not done, as this is not a diagnostic imaging device requiring human interpretation.
6. If a Standalone (algorithm only without human-in-the-loop performance) was done
Not applicable. This is an electro-mechanical device and fluid circuit, not an algorithm.
7. The Type of Ground Truth Used
Not applicable in the typical sense of a diagnostic or predictive device. The "ground truth" here is compliance with "design specifications" and the functionality/performance matching that of the predicate device for "substantial equivalence."
8. Sample Size for the Training Set
Not applicable. This document does not describe a machine learning algorithm or a "training set."
9. How the Ground Truth for the Training Set was Established
Not applicable.
§ 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.”