(263 days)
The Redsense device is intended to monitor for potential blood loss from the hemodialysis access site in hemodialysis patients undergoing hemodialysis treatment. The device includes a blood sensor incorporated into a sensor patch. The sensor monitors potential blood leakage from the venous needle blood access via a light signal and will alarm if blood leakage is detected by the device's sensor.
Redsense Medical provides a system for monitoring the blood access during haemodialysis consisting of an alarm unit and a sensor connected to a specifically developed patch. The Redsense Patch uses integrated optic fibers to detect blood leakage from wounds. The optic fiber is connected to the sensor and alarm unit. If blood leakage occurs during haemodialysis, the patch surrounding the vein needle registers the event and changes a light signal to the alarm unit. This immediately activates a light and an alarm signal. Thus if a vein needle comes out of place extensive blood leakage is prevented.
Acceptance Criteria and Device Performance Study for Redsense Alarm System
The Redsense Alarm System (K130554) is a device intended to monitor for potential blood loss from the hemodialysis access site during hemodialysis treatment. The device includes a blood sensor incorporated into a sensor patch that detects blood leakage via a light signal and alarms if detected.
1. Acceptance Criteria and Reported Device Performance
The core functional acceptance criteria for the Redsense Alarm System are primarily based on sound output level and compliance with relevant electrical and EMC standards. The device's ability to detect blood is validated through non-clinical testing.
| Acceptance Criteria | Reported Device Performance Report |
|---|---|
| Audible Alarm: ≥ 65 dB(A) at 1 meter | Sound test report = 72 dB(A) at 1m |
| EMC requirements | Fulfills IEC 60601-1-2:2001 and IEC 61000-6-1 (for Medical devices + home use) |
| Electrical safety | Verified (not explicitly quantified in the provided text, but stated as fulfilled) |
| Biocompatibility of materials | Verified (not explicitly quantified in the provided text, but stated as fulfilled) |
| Performance (blood detection) | Validated in nonclinical test |
2. Sample Size Used for the Test Set and Data Provenance
The provided document does not describe a specific test set with human subjects for the K130554 device's performance evaluation. The device's performance for blood detection was validated in "nonclinical test." The clinical evidence for the intended use and safety for the subject device (K130554) relies on previous clinical data from a predicate device (K071013).
Regarding the "user evaluation" mentioned:
- Sample Size: Not specified.
- Data Provenance: Not specified, but based on "user feedback," it is likely retrospective or observational use of the predicate device (K071013) that informed design changes for K130554, and potentially some limited prospective evaluation for the K130554 to confirm users "can handle the device and understand its use."
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
This information is not provided as the primary performance validation for blood detection was non-clinical. For the "user evaluation," no details are given about experts or their role in establishing ground truth.
4. Adjudication Method for the Test Set
This information is not provided as there is no detailed description of a clinical test set for K130554's performance.
5. Multi Reader Multi Case (MRMC) Comparative Effectiveness Study
There was no MRMC comparative effectiveness study described for the Redsense Alarm System (K130554) or its predicate devices. The device is an alarm system, not an interpretive diagnostic tool that involves human readers.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
The device's core function is an automated alarm for blood leakage. The "ability to detect blood is validated in nonclinical test." This suggests a form of standalone performance evaluation for the sensor and alarm mechanism without direct human intervention as part of the detection process. However, the details of this non-clinical test are not provided.
7. Type of Ground Truth Used
- For blood detection (non-clinical test): The "ground truth" would have been established by controlled simulations of blood leakage under laboratory conditions, using known quantities and types of blood or blood-like substances to trigger the device's sensor.
- For the clinical evidence (derived from K071013): This would have involved actual patient outcomes and observations of blood loss instances in a clinical setting.
8. Sample Size for the Training Set
This information is not provided. The Redsense Alarm System appears to be based on a deterministic optical principle rather than a machine learning model that typically requires a "training set." The development of its algorithm would be based on engineering specifications and empirical testing.
9. How the Ground Truth for the Training Set Was Established
As noted above, the concept of a "training set" in the context of machine learning does not readily apply to the described device. The "ground truth" for the device's development and validation would have been established through:
- Engineering specifications and physics: Understanding the optical properties of blood and how light interacts with it.
- Empirical testing and calibration: Testing the sensor's response to various concentrations and types of blood in a controlled environment to calibrate its sensitivity and alarm thresholds. This would involve creating controlled blood leakage scenarios and confirming the device's triggering mechanism.
§ 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.