The NxStage System One, consisting of hardware, software and a sterile disposable cartridge, is indicated for the 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 prescription.
Device Story
NxStage System One is a hemodialysis system comprising hardware, software, and a sterile disposable cartridge. It performs hemofiltration, hemodialysis, and ultrafiltration to treat renal failure or fluid overload. The device is operated by a healthcare provider under physician prescription. It processes blood and dialysate through the disposable cartridge to manage patient fluid and solute levels. The system provides therapy to patients in clinical settings, assisting healthcare providers in managing renal conditions and fluid balance.
Clinical Evidence
No clinical data provided. Substantial equivalence is based on design control certification and comparison of technological characteristics.
Technological Characteristics
System consists of hardware, software, and a sterile disposable cartridge. Functions as a high permeability hemodialysis system (21 CFR 876.5860).
Indications for Use
Indicated for patients with renal failure or fluid overload requiring hemofiltration, hemodialysis, or ultrafiltration. Must be administered by a healthcare provider under physician prescription.
Regulatory Classification
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).
Special Controls
*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.”
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K041424
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# Section 7 510(K) Summary
This 510(k) summary of safety and effectiveness information is being submitted in accordance with the requirements of the Safe Medical Device Act (SMDA) of 1990. The contents of this 510(k) summary have been provided in conformance with 21 CFR 1807.92.
| Date: | May 27, 2004 |
|-------------------------------------------------|-----------------------------------------------------------------------------------------------------------------|
| Common/Usual Name: | Hemodialysis System |
| Trade/Proprietary Name: | NxStage System One |
| Classification Name &<br>Device Classification: | Dialyzer, High Permeability with or without<br>Dialysate System; Class II |
| Product Code: | KDI |
| 21 CFR Ref.: | 876.5860 |
| Device Panel: | Gastroenterology-Urology (GU)/Gastro-Renal<br>(GRDB) |
| 510(k) Sponsor &<br>Owner/Operator: | NxStage Medical, Inc<br>439 South Union St, Suite 501<br>South Lawrence, MA 01843<br>Owner/Operator No. 9045797 |
| Contact Person: | Norma LeMay<br>Manager, Regulatory Affairs |
## Device Description:
The NxStage System One, consisting of hardware, software and a sterile disposable cartridge, is indicated for the 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 prescription.
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KC41424
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#### Substantial Equivalence:
This submission is a Special 510(k) Device Modification as described in FDA's guidance document entitled *The New 510(k) Paradigm - Alternate Approaches to Demonstrating Substantial Equivalence in Pre-Market Notifications." In support of this 510(k), NxStage has provided certification of compliance to 21 CFR 820.30 Design Control requirements. The NxStage System One, with one modified warning, has been compared to the Fresenius 2008K and the baseline NxStage System One (K030470) and found to be substantially equivalent.
#### Conclusion:
Based on the device's indication for use, a comparison of descriptive and technological characteristics to the baseline and Fresenius 2008K, and design control certification, the modified NxStage System One device labeling has been shown to meet the minimum requirements that are considered acceptable for its intended use.
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Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is an abstract image of an eagle with three lines representing its wings. The eagle is facing to the left.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
JUL 2 2004
Ms. Norma LeMay Manager, Regulatory Affairs NxStage Medical, Inc. 439 South Union Street 5th Floor LAWRENCE MA 01843
Re: K041424
Trade/Device Name: NxStage System One Regulation Number: 21 CFR §876.5860 Regulation Name: High permeability hemodialysis system Regulatory Class: II Product Code: 78 KDI Dated: May 27, 2004 Received: May 28, 2004
Dear Ms. LeMay:
We have reviewed your Section 510(k) premarket notification of intent to market the device we nave reviewed four becamed the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate for use stated in the enclobare) to tegans to the Medical Device Amendments, or to conninered provide to may 20, 1978) in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act (Act (Act that do not require approval approval application (PMA). and Cosmette for (10) that do nev sequent to the general controls provisions of the Act. The r ou may, atorely provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into cither class II (Special Controls) or class III (PMA), it your dovied is bluestilied were are as . 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 r lease of as now a had i bermination that your device complies with other requirements of the Act that I Dr Has Interes and regulations administered by other Federal agencies. You must or urf I vatin bathere is requirements, including, but not limited to: registration and listing Comply with an the Not 11st Progantially, t 801); good manufacturing practice requirements as set (21 CFR Part 820) regulation (21 CFR Part 820); and if applicable, the electronic rordly in the quality by stations (sections 531-542 of the Act); 21 CFR 1000-1050.
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This letter will allow you to begin marketing your device as described in your Section 510(k) This letter will allow you to ocgin marketing of substantial equivalence of your device to a legally premarket notification. The PDA mioning of backless of the results your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please It you desire specific advice for your dones on one of the following numbers, based on the regulation number at the top of the letter:
| 8xx. 1xxx | (301) 594-4591 |
|----------------------------------|----------------|
| 876.2xxx, 3xxx, 4xxx, 5xxx | (301) 594-4616 |
| 884.2xxx, 3xxx, 4xxx, 5xxx, 6xxx | (301) 594-4616 |
| 892.2xxx, 3xxx, 4xxx, 5xxx | (301) 594-4654 |
| Other | (301) 594-4692 |
Additionally, for questions on the promotion and advertising of your device, please contact the Additionally, Tor questions of the promotion in the regulation entitled, "Misbranding
Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Mis Othce of Compliance at (301) 57 + 1059. Fact 807.97) you may obtain. Other general by reference to prematical nonitodion (2) ex extenned from the Division of Strall information on your responsionalis and Consumer Assistance at its toll-free number (800) 638-2041 or Manufacturers, International and Collisanter - Leaver - Leaver - Schools - School
Sincerely yours,
Nancy C. Brogdon
Nancy C. Brogdon Director, Division of Reproductive, Abdominal and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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### Indications for Use
510(k) Number (if known):
K041424
Device Name:
NxStage System One
Indications for Use:
The NxStage System One is indicated for the 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 prescription.
Prescription Use _____________________________________________________________________________________________________________________________________________________________ × (Part 21 CFR 801 Subpart D) AND/OR
Over-The-Counter Use_ (21 CFR 807 Subpart C)
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Nancy C brogdon
Division Sign-Off)
Division of Reproductive, Abdominal,
and Radiological Devices
510(k) Number K041424
Page 1 of 1
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.
