(227 days)
The Redsense device is intended to monitor for potential blood loss from the hemodialysis access site in hemodialysis patients undergoing hemodialysis treatment up to 5 hours at home or in the clinical setting. The device includes a blood sensor incorporated into an adhesive dressing. The sensor monitors potential blood leakage from the needle puncture via an infrared light and will alarm if needle dislodgement or blood leakage is detected.
All use must be administrated under physician's prescription, and must be observed by a trained and qualified person considered to be competent in the use of this device by the prescribing physician.
Redsense Home Use is a system for monitoring the vein or arterial needle during hemodialysis. Redsense consists of an alarm unit and optical sensor incorporated into an adhesive patch. The patch with the sensor is placed around the vein needle and detects any blood that drips onto the patch if the needle has been accidentally pulled out or if there is leakage during dialysis. If blood loss is detected, the device will alarm.
Here's a breakdown of the acceptance criteria and study information for the Redsense - Home Use device, organized by your requested points:
1. Table of Acceptance Criteria and Reported Device Performance
The provided document describes the types of tests performed and their general success, rather than specific numerical acceptance criteria for performance metrics like sensitivity or specificity. The focus is on demonstrating that the device meets safety and functionality requirements for home use.
| Acceptance Criteria Category | Reported Device Performance (Summary) |
|---|---|
| Audible Alarm Capability | Performed according to "Class II Special Controls Guidance Document: Apnea Monitors" and met requirements. Sound level increased for home use. |
| Visual Alarm Capability | Tested against ISO 9703-1:1992: "Alarm signals for anesthesia and respiratory care. Part 1. Specification for visual alarm signals." Results met the requirements. |
| User Evaluation (Home Use) | Device could be used by patients, and Instructions for Use were sufficient. Amount of false alarms and warnings did not increase compared to clinical settings. No adverse effects observed. Device functioned successfully in the home use environment. |
| Compliance with Requirement Specifications and FDA Requirements | Verification testing, including additional tests for audible and visual alarms, confirmed the Redsense Home Use device fulfills these. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for User Evaluation (Test Set): 8 patients
- Data Provenance: Sweden (patients undergoing self-dialysis at a clinic or home dialysis in Sweden). The study was a prospective user evaluation of the device in its intended use environment.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not explicitly state the number of experts or their specific qualifications for establishing ground truth in the user evaluation. The user evaluation focused on patient usability and false alarm rates, not on the diagnostic accuracy against an independent "gold standard" truth. It mentions that use "must be observed by a trained and qualified person considered to be competent in the use of this device by the prescribing physician," implying supervision, but not a panel of experts for ground truth assessment in the study itself.
4. Adjudication Method for the Test Set
The document does not describe a formal adjudication method (like 2+1 or 3+1). The user evaluation for false alarms and warnings likely relied on observations by the patients themselves and/or the "trained and qualified person" overseeing the treatment, rather than a blinded expert panel adjudication process for each event.
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, an MRMC comparative effectiveness study involving human readers and AI assistance was not performed. This device is a standalone blood loss detection system, not an AI-assisted diagnostic tool that aids human interpretation.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, the primary evaluation of the Redsense device, particularly the alarm capabilities (audible, visual, and detection of blood leakage), represents a standalone performance assessment. The user evaluation then confirmed that this standalone device functioned appropriately in the home-use context with actual patients, but the core detection and alarming are performed by the algorithm/sensor itself without human intervention in the detection process.
7. The Type of Ground Truth Used
- For the audible and visual alarm tests, the "ground truth" was defined by the requirements outlined in "Class II Special Controls Guidance Document: Apnea Monitors" and ISO 9703-1:1992.
- For the user evaluation, the "ground truth" related to device functionality (e.g., whether it could be used by patients, if instructions were sufficient, whether false alarms increased, or if adverse effects occurred) was established through direct observation during home or clinic dialysis and patient feedback. The "blood loss detection" aspect's ground truth would have been real or simulated blood leakage events (though specifics aren't detailed in the provided excerpt for the home use study; it only states detection if "blood loss is detected").
8. The Sample Size for the Training Set
The document does not provide information about a "training set" for an algorithm. This device is an alarm system based on sensor detection (infrared light detecting blood), rather than a machine learning model that requires a discrete training phase.
9. How the Ground Truth for the Training Set Was Established
As there is no explicit mention of a training set or a machine learning algorithm, information on how ground truth was established for a training set is not applicable or provided in the given text. The device's operation is based on a direct physical principle (infrared light detection of blood).
§ 876.5820 Hemodialysis system and accessories.
(a)
Identification. A hemodialysis system and accessories is a device that is used as an artificial kidney system for the treatment of patients with renal failure or toxemic conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and accessories. Blood from a patient flows through the tubing of the extracorporeal blood system and accessories to the blood compartment of the dialyzer, then returns through further tubing of the extracorporeal blood system to the patient. The dialyzer has two compartments that are separated by a semipermeable membrane. While the blood is in the blood compartment, undesirable substances in the blood pass through the semipermeable membrane into the dialysate in the dialysate compartment. The dialysate delivery system controls and monitors the dialysate circulating through the dialysate compartment of the dialyzer.(1) The extracorporeal blood system and accessories consists of tubing, pumps, pressure monitors, air foam or bubble detectors, and alarms to keep blood moving safely from the blood access device and accessories for hemodialysis (§ 876.5540) to the blood compartment of the dialyzer and back to the patient.
(2) The conventional dialyzer allows a transfer of water and solutes between the blood and the dialysate through the semipermeable membrane. The semipermeable membrane of the conventional dialyzer has a sufficiently low permeability to water that an ultrafiltration controller is not required to prevent excessive loss of water from the patient's blood. This conventional dialyzer does not include hemodialyzers with the disposable inserts (Kiil type) (§ 876.5830) or dialyzers of high permeability (§ 876.5860).
(3) The dialysate delivery system consists of mechanisms that monitor and control the temperature, conductivity, flow rate, and pressure of the dialysate and circulates dialysate through the dialysate compartment of the dialyzer. The dialysate delivery system includes the dialysate concentrate for hemodialysis (liquid or powder) and alarms to indicate abnormal dialysate conditions. This dialysate delivery system does not include the sorbent regenerated dialysate delivery system for hemodialysis (§ 876.5600), the dialysate delivery system of the peritoneal dialysis system and accessories (§ 876.5630), or the controlled dialysate delivery system of the high permeability hemodialysis system § 876.5860).
(4) Remote accessories to the hemodialysis system include the unpowered dialysis chair without a scale, the powered dialysis chair without a scale, the dialyzer holder set, dialysis tie gun and ties, and hemodialysis start/stop tray.
(b)
Classification. (1) Class II (performance standards) for hemodialysis systems and all accessories directly associated with the extracorporeal blood system and the dialysate delivery system.(2) Class I for other accessories of the hemodialysis system remote from the extracorporeal blood system and the dialysate delivery system, such as the unpowered dialysis chair, hemodialysis start/stop tray, dialyzer holder set, and dialysis tie gun and ties. 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 § 876.9.