(23 days)
Both electrolyte buffers are used to measure sodium, chloride, potassium, and carbon dioxide concentrations in serum or plasma, sodium, potassium, and chloride concentrations in urine, and chloride concentrations in CSF on the SYNCHRON CX 3 System
The Sigma Diagnostics methods use ion selective electrodes for determining sodium, potassium, and chloride and rate of pH change for determing carbon dioxide on the SYNCHRON CX 3 System.
The provided text describes the summary of safety and effectiveness for the Sigma Diagnostics CX®3 Electrolyte Buffer, Procedure Number E3766. It focuses on demonstrating substantial equivalence to a predicate device (Beckman Electrolyte Buffer Kit, Part No. 443325) through comparison studies, precision, and linearity.
Here's an analysis based on your requested information:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implied by the comparison to a predicate device, focusing on correlation coefficients, regression equations indicating agreement, and acceptable levels of precision and linearity.
| Test Aspect | Acceptance Criteria (Implied by Predicate Equivalence) | Reported Device Performance |
|---|---|---|
| Correlation to Predicate (Serum) | High correlation coefficients (e.g., typically >0.95 for quantitative assays) | Sodium: 0.963 |
| Potassium: 0.999 | ||
| Chloride: 0.973 | ||
| Total CO₂: 0.992 | ||
| Regression to Predicate (Serum) | Regression equation close to y = 1x + 0 (i.e., slope near 1, intercept near 0) | Sodium: y = 0.90x + 13.48 |
| Potassium: y = 0.98x + 0.08 | ||
| Chloride: y = 0.91x + 10.52 | ||
| Total CO₂: y = 0.95x + 1.54 | ||
| Correlation to Predicate (Urine) | High correlation coefficients (e.g., typically >0.95 for quantitative assays) | Sodium: 0.997 |
| Potassium: 0.998 | ||
| Chloride: 0.997 | ||
| Regression to Predicate (Urine) | Regression equation close to y = 1x + 0 | Sodium: y = 0.95x - 0.10 |
| Potassium: y = 0.97x + 0.49 | ||
| Chloride: y = 0.97x + 2.06 | ||
| Correlation to Predicate (CSF) | High correlation coefficient (e.g., typically >0.95) | Chloride: 0.891 |
| Regression to Predicate (CSF) | Regression equation close to y = 1x + 0 | Chloride: y = 0.98x + 4.00 |
| Precision (Serum) | Low %CVs (e.g., typically |
§ 862.1160 Bicarbonate/carbon dioxide test system.
(a)
Identification. A bicarbonate/carbon dioxide test system is a device intended to measure bicarbonate/carbon dioxide in plasma, serum, and whole blood. Bicarbonate/carbon dioxide measurements are used in the diagnosis and treatment of numerous potentially serious disorders associated with changes in body acid-base balance.(b)
Classification. Class II.