(166 days)
The AmeriWater Alarm Panel is intended for use in hospitals and dialysis clinics as an optional component in the AmeriWater Water Purification System (WPS) for hemodialysis applications. The AmeriWater Alarm Panel is intended to notify the operator of conditions that exist with the Water Purification System requiring the operator's attention. The AmeriWater WPS is intended to remove organic and inorganic substances and microbial contaminants from water. The Purified (or treated) water will then be used to prepare and dilute dialysate concentrate to form dialysate and/or rinse dialyzers for multiple use and/or to prepare dilute solutions for reprocessing procedures in multiple-use dialyzers. The Alarm Panels are designed to meet current AAMI and Federal (U.S.) standards.
The AmeriWater Alarm Panel is designed to let technicians and nurses know when something is not functioning properly with the water equipment. The Alarm Panels warn the user by illuminating an alarm light and sounding an audible alarm, indicating that some limit has been exceeded. This submission is for a design change to the existing AmeriWater Alarm Panel cleared for market use in the AmeriWater Water Purification System (WPS) for hemodialysis applications (K991519). The AmeriWater Alarm Panel design has been upgraded from a panel with switches operating relays, to a digital panel operated by a microprocessor. All of the Alarm Panels are provided with an LCD display that will indicate the status of the water system. The nurse's station remote will correspond to what is indicated on the alarm panel. The selection of possible water properties to be monitored has been chosen during the original purchase of this equipment. The properties that this system can monitor include Low Resistivity, High Conductivity, R/O Alarm, Low Storage Tank, and Low Bicarb. There are also 5 additional dry contact inputs provided.
The AmeriWater Alarm Panel (K121022) is a Class II medical device intended to notify operators of conditions within the AmeriWater Water Purification System (WPS) for hemodialysis applications. It is an upgrade from a relay-based system to a microprocessor-controlled digital panel with an LCD display.
1. Table of Acceptance Criteria and Reported Device Performance:
The document describes the device's functions and how it meets AAMI and Federal (U.S.) standards. However, it does not provide specific quantitative acceptance criteria or detailed numerical performance metrics in a tabular format. Instead, it offers a general statement of successful performance based on functional verification.
The table below summarizes the listed functionalities of the K121022 AmeriWater Alarm Panel compared to the predicate device (K991519) and the reported performance.
| Feature / Acceptance Criteria (Implied) | K991519 Alarm Panel (Predicate) Performance (Baseline) | K121022 Alarm Panel Performance (Reported) |
|---|---|---|
| Core Function: Central monitoring of water treatment system | Central monitor of the water treatment system. | Central monitor of the water treatment system. Reported as successful. |
| Operation Method: Switches vs. Digital | Switches operating relays | Digital operation controlled by microprocessor. Test verified all alarm functions operate as intended and meet design specifications. |
| Electrical Circuit: Operating voltage | Operated on 115V electrical circuit | Operated on 115V electrical circuit. Test verified all alarm functions operate as intended and meet design specifications. |
| Remote Alarm Power: Voltage transformation | Transforms down to a 24V for the remote alarm | Transforms down to a 24V for the remote alarm. 24 VAC lights were used to verify operation of 24 VAC outputs, successful. |
| Conductivity/Resistivity Monitoring | Off the shelf conductivity and resistivity monitors installed in panel | Conductivity and resistivity monitoring integrated into control. Test data indicates monitors are accurate when compared to a known standard over expected operational ranges. |
| Alarm Types: Audible and visible alarms | Audible and visible alarms | Audible and visible alarms. Test verified all alarm functions operate as intended and meet design specifications. |
| Remote Interface: Audio and visual alarms on remote | Interfaces with the remote alarm; also with audio and visual alarms | Interfaces with the remote alarm; also with audio and visual alarms. Test verified all alarm functions operate as intended and meet design specifications. |
| Alarm Silence Location: Only main panel | Silence button only located on the main panel in the water room | Silence button only located on the main panel in the water room. Test verified all alarm functions operate as intended and meet design specifications. |
| Alarm Silence Reset Time: 180 seconds | Silence button has a 180 second reset. | Silence button has a 180 second reset. Test verified all alarm functions operate as intended and meet design specifications. |
| Visible Alarm Status during Silence: Active | Visible alarms remain active when audible alarm is silenced. | Visible alarms remain active when audible alarm is silenced. Test verified all alarm functions operate as intended and meet design specifications. |
| Water Quality Display: | Good Water Light | Water quality digital display. Test verified all alarm functions operate as intended and meet design specifications. |
| Specific Alarms (RO, Storage Tank, Conductivity, Resistivity, Bicarb Low) | Alarm light w/ audible alarm for each. | Alarm light w/ audible alarm and digital display for each (except Remote Bicarb Low which is only light w/ audible). Test verified all alarm functions operate as intended and meet design specifications. |
| Additional Contact Inputs: | No additional contact inputs | 5 additional dry contact inputs. Test verified all alarm functions operate as intended and meet design specifications. |
| Compliance with Standards: | Not explicitly stated in this section for K991519, but implied as predicate. | Designed to meet current AAMI and Federal (U.S.) standards. Performance testing was successful and all acceptance criteria were met, including AAMI requirements. |
| Software Validation: | Not applicable (relay-based) | Conducted in accordance with requirements for a software device with a moderate level of concern. Successful. |
2. Sample size used for the test set and the data provenance:
- Test Set Sample Size: "Each of the test units was bench tested." "100% of distributed product will be subjected to performance testing prior to shipment." While the exact number of units bench tested for this submission is not explicitly stated as a single number, it indicates that
- performance testing was conducted on "initial production units representing the approved final design."
- all possible features were tested on these units.
- 100% of distributed product will undergo similar performance testing.
- Data Provenance: The testing was conducted in-house by AmeriWater as part of their design verification and validation process for a design change to an existing device. It is therefore prospective for the new design. The document does not specify a country of origin for the data other than the company being based in the USA.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The document does not mention the use of external experts or a formal "ground truth" establishment by experts for the performance testing.
- The testing was focused on verifying the device's functional operation against its design specifications and AAMI requirements. This suggests that internally defined technical specifications and AAMI standards served as the "ground truth" or reference for performance.
4. Adjudication method for the test set:
- No adjudication method (e.g., 2+1, 3+1) is mentioned as the testing performed was functional verification against design specifications and AAMI standards, not subjective assessment requiring multiple adjudicators.
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:
- No MRMC comparative effectiveness study was done for this device. This device is an alarm panel for a water purification system, not an imaging or diagnostic AI-assisted device that would involve human "readers" or AI assistance in interpretation.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- This device is not an AI algorithm. It is a microprocessor-controlled alarm panel. The "standalone" performance in this context refers to the device's ability to accurately detect and signal conditions according to its programming and sensor inputs, which was verified through bench testing. The software validation was conducted for a moderate level of concern, indicating the algorithm (control logic) was tested without human intervention in its core alarm triggering functionalities.
7. The type of ground truth used:
- The ground truth used was based on:
- Design Specifications: The intended operational parameters and alarm thresholds defined during the design phase of the AmeriWater Alarm Panel.
- AAMI Standards: Compliance with current AAMI (Association for the Advancement of Medical Instrumentation) standards for water purification systems for hemodialysis.
- Known Standards for Sensor Accuracy: For conductivity and resistivity monitors, comparison to "a known standard over the operation ranges expected" served as the ground truth for their accuracy.
8. The sample size for the training set:
- This device is a hardware device with embedded software (microprocessor-controlled). It does not employ machine learning or AI algorithms that require a "training set" in the conventional sense of data-driven model learning. The software was developed and validated, not "trained."
9. How the ground truth for the training set was established:
- As there is no conventionally defined "training set" for this device, the concept of establishing ground truth for it does not apply in the context of machine learning. The software's logic and parameters are based on engineering design, AAMI standards, and the requirements for monitoring water quality in hemodialysis systems.
§ 876.5665 Water purification system for hemodialysis.
(a)
Identification. A water purification system for hemodialysis is a device that is intended for use with a hemodialysis system and that is intended to remove organic and inorganic substances and microbial contaminants from water used to dilute dialysate concentrate to form dialysate. This generic type of device may include a water softener, sediment filter, carbon filter, and water distillation system.(b)
Classification. Class II (special controls). The device, when it is a water purification subsystem disinfectant, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 876.9.