(105 days)
The VacuLink is intended for obstetric use in the measurement and recording of data related to vacuum-assisted delivery (such as vacuum, number and duration of pulls and number of pop-offs) on the strip chart.
The VacuLink is a small, battery powered single-use vacuum measuring device. It is connected in parallel to the vacuum chamber of commercial handheld vacuum assisted delivery systems (i.e. Mityvac & Kiwi PalmPump). As a redundant gauge to the vacuum gauges on those devices, it electronically measures the vacuum applied to the fetal head during a vacuum assisted delivery. It connects to the vacuum port of the maternal/fetal monitor (i.e. HP, Corometrics and Spacelabs) via electrical cable. The vacuum value is numerically displayed in centimeters of mercury (cm Hg). The vacuum value is also recorded from the uterine activity channel of the maternal/fetal monitor and it is permanently stored in the hospital database. The information may also be displayed on a video monitor as well.
The VacuLink incorporates a light sequence of red, yellow, and green. When the VacuLink is first connected to the maternal/fetal monitor, all three lights will flash in sequence as a quick test of the internal components. At the successful completion of the test, the green LED illuminates until the VacuLink is disconnected from the maternal/fetal monitor. A flashing yellow LED illuminates when the battery voltage is low and the VacuLink should be replaced. If a VacuLink that has been used previously and is reconnected, the red LED illuminates indicating the VacuLink is no longer operational.
Here's an analysis of the provided text regarding the VacuLink device, focusing on acceptance criteria and study information:
1. Table of Acceptance Criteria and Reported Device Performance
| Criteria | Acceptance Value | Reported Device Performance |
|---|---|---|
| Claimed accuracy/tolerance | At 70 cm Hg = 3.26% on the VacuLink (inherent) | At 70 cm Hg = 3.26% (matches claim) |
| Comparative Accuracy | At least as accurate as comparable vacuum gauges | "More accurate by a factor of 10" than comparable gauges in clinical use. |
| Electrical Safety & EMC Conformance | Conformance to applicable standards | "Electrical safety and EMC testing was also performed to demonstrate conformance to applicable standards." |
| Software Validation | Validated | "Software validation...have also been provided." |
| Sterilization Process Information | Provided and validated (implied for a single-use device) | "Sterilization process information have also been provided." |
Note: The document primarily focuses on the device's accuracy and comparison to predicate devices, rather than explicitly listing "acceptance criteria" as pass/fail thresholds for a primary clinical endpoint. The "Claimed accuracy/tolerance" is presented as a characteristic of the device itself, which then needs to be demonstrated. The comparative accuracy against existing devices could be considered an acceptance criterion for market clearance.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size (Clinical Phase): Not explicitly stated. The document mentions an "Initial clinical phase (feasibility study)" but does not provide details on the number of subjects or cases included in this study.
- Data Provenance: Not explicitly stated. Given that the device is manufactured by Medevco, Inc. in Dallas, TX, and the submission is to the FDA, it's likely the clinical feasibility study (if conducted with patients) was in the US. The nature of "Initial bench testing" and "Secondary bench testing" implies laboratory or engineering environments. It's a prospective study as implies "Initial clinical phase (feasibility study)" to study a new device.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
Not explicitly stated. The document does not provide details on who established the "ground truth" for the clinical feasibility study, or if "ground truth" for vacuum measurements was established by a separate, highly accurate reference device independent of human interpretation.
4. Adjudication Method for the Test Set
Not explicitly stated. The document does not describe any expert adjudication process for the clinical feasibility study. For the bench testing, the "ground truth" would likely be established by a highly accurate, calibrated reference instrument, not human adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
Not applicable. The VacuLink is a vacuum measuring device, not an imaging or diagnostic device that typically involves human interpretation of results in an MRMC study. Its function is to provide an objective measurement (vacuum pressure) and record data. Therefore, an MRMC study assessing human reader improvement with AI assistance is not relevant to this device.
6. Standalone Performance Study
Yes, a standalone performance study was done implicitly through the "Performance Data & Conclusions" section.
- The initial and secondary bench testing phases directly assess the standalone performance of the VacuLink device against certified reference instruments. The statement "Performance testing of VacuLink... reveals that the VacuLink is as accurate as the claimed accuracy" and "VacuLink was more accurate by a factor of 10" (in clinical use, compared to uncalibrated existing gauges) directly addresses its standalone measurement capability.
- The "Initial clinical phase (feasibility study)" would also have assessed its standalone functionality in a real-world setting, though specific data from this phase is not provided in detail.
7. Type of Ground Truth Used
- Bench Testing: Certified reference instruments (for vacuum measurement).
- Clinical Feasibility Study: Implicitly, the actual vacuum applied during an assisted delivery, as measured by the VacuLink and potentially compared to existing devices. The document highlights the "lack of calibration of the comparable vacuum gauges" in clinical use, suggesting the VacuLink aimed to provide a more reliable ground truth in that setting.
8. Sample Size for the Training Set
Not applicable. The VacuLink is a hardware device for measuring vacuum pressure and recording data. It is not an AI/ML-based device that requires a "training set" in the conventional sense. The "training" for such a device involves engineering design, component selection, and calibration, not machine learning model training on a dataset.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no "training set" in the context of AI/ML for this device. The accuracy of the device itself would be established through a rigorous calibration process using highly stable and accurate reference pressure gauges.
§ 884.4340 Fetal vacuum extractor.
(a)
Identification. A fetal vacuum extractor is a device used to facilitate delivery. The device enables traction to be applied to the fetal head (in the birth canal) by means of a suction cup attached to the scalp and is powered by an external vacuum source. This generic type of device may include the cup, hosing, vacuum source, and vacuum control.(b)
Classification. Class II (performance standards).