(76 days)
For in vitro diagnostic use only. VITROS Na DT Slides quantitatively measure sodium (Na ) concentration in serum and plasma. Measurements used by this device are used in the diagnosis and treatment of aldosteronism, diabetes insipidus, adrenal hypertension, Addison's disease, dehydration, inappropriate antidiuretic hormone secretion, or other disease involving electrolyte imbalance.
The VITROS Chemistry Products Nat DT Slide assay is performed using the VITROS Chemistry Products Na DT Slide and the VITROS Chemistry Products DT Calibrator Kit on the VITROS DT60/DT60 II Chemistry Systems. The VITROS Na " DT Slide is a multilayered, analytical element coated on a polyester support that uses direct potentiometry for measurement of sodium ions. All reactions necessary for a single quantitative measurement of sodium take place within the multi-layered analytical element of a VITROS Chemistry Products Na DT Slide. The slide consists of two ion-selective electrodes, each containing methyl monensin (an ionophore for sodium), a reference layer, and a silver layer and a silver chloride layer coated on a polyester support.
VITROS Chemistry Products Na DT Slides use ion-selective electrodes for potentiometric measurements of ionic sodium. Ionic sodium determinations are made by simultaneously depositing 10 uL each of a reference fluid and a sample fluid on separate halves of the VITROS Chemistry Products Na DT Slide. The electrode receiving the reference fluid is identified as the reference electrode. A paper bridge connects the reference electrode and the indicator electrode. which receives the sample fluid. A stable liquid junction between the two fluids is formed in the paper bridge. The sodium ions in the tested reference and sample fluids migrate to the silver silver silver chloride lavers and establishes equilibrium.
After an incubation period, the electrometer in the VITROS Chemistry System measures the potential difference between the reference and indicator electrodes. Each electrode responds to the activity of sodium ions in the respective fluids to produce a potential for the concentration cell. The VITROS DT60/DT6011 Chemistry System's microprocessor uses this measurement and the stored calibration parameters to determine the concentration value of the sodium ion in the sample fluid. The test result is reported in millimoles per liter (mmol/ L).
VITROS Chemistry Products DT Calibrator Kit contains four levels of lyophilized standards with corresponding diluents. The standards are prepared from bovine serum albumin and processed bovine serum to which enzymes, electrolytes, stabilizers, preservatives and other organic analytes have been added. The companion diluents are prepared from processed water to which inorganic salts have been added.
The VITROS DT60 II Chemistry System and reagents are designed specifically for use with the VITROS Chemistry Products range of products.
Here's a breakdown of the acceptance criteria and study information for the VITROS Chemistry Products Na+ DT Slides based on the provided document:
This 510(k) pertains to a modified device (VITROS Chemistry Products Na+ DT Slides) and compares it to a predicate device, focusing on demonstrating substantial equivalence, rather than establishing performance against new acceptance criteria. Therefore, the "acceptance criteria" are implicitly the performance of the predicate device.
1. Table of Acceptance Criteria and Reported Device Performance
The document states that "Equivalence was demonstrated using manufactured slides along with patient and quality control samples with measured sodium values spanning the assay range." It does not provide specific numerical acceptance criteria (e.g., precision, accuracy ranges) or granular performance data for the modified device. Instead, it concludes the modified device is "substantially equivalent" to the predicate.
| Characteristic | Acceptance Criteria (Implied by Predicate Device Performance) | Reported Device Performance (Modified Device) |
|---|---|---|
| Ability to measure sodium (Na+) concentration in serum and plasma quantitatively. | Successfully measures Na+ concentration in serum/plasma using direct potentiometry. (Performance of K081411 and K083680) | Successfully measures Na+ concentration in serum/plasma using direct potentiometry; demonstrated substantial equivalence to predicate. |
| Performance across the assay range. | Performance of predicate device (K081411) with patient and quality control samples spanning the assay range. | Demonstrated substantial equivalence to predicate device with patient and quality control samples spanning the assay range. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not explicitly stated in terms of an exact number. The document mentions "patient and quality control samples with measured sodium values spanning the assay range."
- Data Provenance: Not explicitly stated (e.g., country of origin). The study involved "patient and quality control samples," suggesting a mix of clinical and controlled laboratory samples. It is a retrospective comparison against the performance of the predicate device, although the data collection for the modified device would be prospective for the purpose of this submission.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
Not applicable. This submission is for an in vitro diagnostic device, where ground truth for analyte concentration is typically established by reference methods or validated laboratory instruments, not by expert interpretation of images or clinical scenarios.
4. Adjudication Method for the Test Set
Not applicable. This is not a study involving human readers or interpretation requiring adjudication.
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
Not applicable. This is not an AI-assisted diagnostic device, nor does it involve human readers interpreting cases.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
This device is a standalone diagnostic test system (reagents and associated instrument). The performance evaluated is the accuracy and precision of the analytical system itself in measuring sodium concentration. The document demonstrates this through "equivalence" to the predicate, implying standalone performance.
7. The Type of Ground Truth Used
The ground truth for the sodium concentration in the samples would have been established by:
- Reference methods for sodium measurement.
- Validated laboratory instruments or established values for quality control samples.
- The predicate device's cleared performance, against which the modified device was compared for equivalence.
8. The Sample Size for the Training Set
Not applicable. This device is not an AI/machine learning algorithm that requires a "training set" in the conventional sense. Its performance is based on the chemical and electrochemical principles of ion-selective electrodes.
9. How the Ground Truth for the Training Set was Established
Not applicable, as there is no "training set" for this type of device.
§ 862.1665 Sodium test system.
(a)
Identification. A sodium test system is a device intended to measure sodium in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of aldosteronism (excessive secretion of the hormone aldosterone), diabetes insipidus (chronic excretion of large amounts of dilute urine, accompanied by extreme thirst), adrenal hypertension, Addison's disease (caused by destruction of the adrenal glands), dehydration, inappropriate antidiuretic hormone secretion, or other diseases involving electrolyte imbalance.(b)
Classification. Class II.