(13 days)
The Davol AquaSens Fluid Monitoring System 4000 is intended for use in gynecological surgical and diagnostic procedures. The system consolidates the supply and collection of irrigation fluids used during hysteroscopic procedures to distend the uterus and to clear the operative site of blood and debris. The system monitors irrigation fluid losses/gains and indicates when such losses/gains exceed a level pre-set by the surgeon.
The major components of the AquaSens FMS 4000 are a load cell assembly which includes an IV pole structure for supporting irrigation bags and fluid suction canisters and an Electronic Control Unit (ECU) that acquires information from the load cell assembly to calculate and display fluid loss/gain based on changes in total weight after the system is initialized.
Here's a breakdown of the acceptance criteria and study findings for the AquaSens Fluid Monitoring System 4000, based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state numerical acceptance criteria. Instead, it relies on a comparison to a predicate device. The implied acceptance criterion is that the new device performs "within the given specifications" and demonstrates "substantially equivalent" performance to the predicate device.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Functional Equivalence to Predicate Device: To detect loss of fluid weight by identifying discrepancies between fluid input and output by tracking changes in total system fluid weight, then converting the information for display through the Electronic Control Unit. | The proposed device (AquaSens FMS 4000) maintains this core functionality. |
| Accuracy in Weight Loss Measurement: Performance in AC, DC, and low battery modes. | "The test results indicated that both the proposed and predicate device performed within the given specifications under the same test conditions." (This implies the AquaSens FMS 4000 met the same performance standards as the AquaSens FMS 3000 in these modes, though specific thresholds are not provided). |
| Switching Characteristics of Modes: User interface for changing between PAUSE and RUN modes. | The proposed device has a re-designed interface for changing between PAUSE and RUN modes (eliminating a toggle bar and replacing it with two membrane buttons). The performance data states that "switching characteristics of modes" was tested, and the conclusion is substantial equivalence, suggesting the new interface performs acceptably. |
| Compliance with UL 2601-1 (International Harmonized Standard for Medical Electrical Equipment): (Implicit regulatory and safety requirement) | Underwriter Laboratories was "currently conducting the necessary tests," and the device would "not be marketed until all necessary test requirements under UL 2601-1... are satisfied." |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: Not explicitly stated. The document refers to "laboratory testing" conducted to compare the devices.
- Data Provenance: The testing was conducted internally by Davol, Inc. ("Laboratory testing was conducted to compare the proposed device to the predicate device."). There is no mention of country of origin for the data or whether it was retrospective or prospective. It appears to be prospective lab testing.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
Not applicable. This device is a fluid monitoring system, not an AI or diagnostic imaging device that relies on expert interpretation of data to establish ground truth. The "ground truth" for its performance would be highly accurate weight measurements and electrical/mechanical performance metrics.
4. Adjudication Method for the Test Set
Not applicable. As noted above, this isn't a study involving human interpretation. The testing involved direct measurement and comparison to specifications of a mechanical/electronic device.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study was not done. This type of study is typically used for diagnostic or imaging devices where human interpretation plays a role.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, the performance study effectively constitutes a standalone evaluation. The "laboratory testing" assesses the device's intrinsic ability to measure weight loss and manage modes, independent of a human operator's influence on its core measurement function. While a human interacts with the device (e.g., initiating PAUSE/RUN), the performance data focuses on the device's mechanical and electronic accuracy in response to these inputs and fluid changes.
7. The Type of Ground Truth Used
The ground truth used for this type of device would be:
- Accurate Weight Measurements: Using calibrated scales or industrial standards to verify the device's ability to accurately measure fluid weight changes.
- Electrical and Mechanical Specifications: Compliance with engineering specifications for power modes (AC, DC, low battery) and button functionality.
8. The Sample Size for the Training Set
Not applicable. This device is a fluid monitoring system, not a machine learning or AI algorithm that requires a "training set" in the conventional sense. Its functionality is based on established physical principles (weight measurement) and electronic design, not learned patterns from data.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no training set for this type of device.
§ 884.1700 Hysteroscopic insufflator.
(a)
Identification. A hysteroscopic insufflator is a device designed to distend the uterus by filling the uterine cavity with a liquid or gas to facilitate viewing with a hysteroscope.(b)
Classification. (1) Class II (performance standards).(2) Class I for tubing and tubing/filter fits which only include accessory instruments that are not used to effect intrauterine access, e.g., hysteroscopic introducer sheaths, etc.; and single-use tubing kits used for only intrauterine insufflation. 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 § 884.9.