(193 days)
The Chrono-log WBA, Model 591A/592A is intended for determination of platelet function in a whole blood specimen, using ADP, Collagen and Ristocetin reagents.
For Platelet Function testing of Whole Blood specimens using Impedance Aggregometry. For Prescription Use.
The Chrono-log WBA, Model 591A/592A uses electrical impedance to measure platelet aggregation in a whole blood sample. The Impedance is measured using a Disposable electrode with two precious metal pins. A small voltage is applies across these two pins. When the electrode is placed into a diluted whole blood specimen and a monolayer is formed around the two pins. In the absence of an agonist, the platelet build-up stabilizes and a baseline is established. When an agonist is added to the specimen, the platelets begin to aggregate and collect on the electrode pins causing a change in impedance. The change of impedance is directly proportional to the amount of Aggregation in the specimen. This change of impedance is displayed on a front panel readout. The instrument has an analog output which produces an aggregation curve when connected to a strip chart recorder or AGGRO/LINK interface. Model 591 A is a single channel version; Model 592A is the duel channel version.
This document describes the performance testing of the Chrono-log Whole Blood Aggregometer (WBA), Model 591A/592A, and its substantial equivalence to the predicate device, Model 591/592, with the primary difference being the introduction of disposable electrodes.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria were primarily based on demonstrating substantial equivalence to the predicate device through correlation, statistical significance, and the ability to detect aggregation changes and patient conditions similarly. New normal ranges were also established.
| Acceptance Criteria / Performance Metric | Predicate Device (Reusable Electrodes) | New Device (Disposable Electrodes) | Reported Performance (New vs. Predicate) | Outcome / Acceptance |
|---|---|---|---|---|
| Overall Correlation (Pearson's R) | N/A | N/A | R = 0.84 (250 samples) | Met |
| Paired t-test | N/A | N/A | P 5 Ω | Established / Close to predicate |
*Note on R for ADP 20μM: The Pearson's R value of 0.61 is marked with an asterisk indicating p
§ 864.5700 Automated platelet aggregation system.
(a)
Identification. An automated platelet aggregation system is a device used to determine changes in platelet shape and platelet aggregation following the addition of an aggregating reagent to a platelet-rich plasma.(b)
Classification. Class II (performance standards).