(60 days)
The Stat Profile Prime Plus Analyzer System is intended for use by healthcare professionals in clinical laboratory settings and for point-of-care usage for quantitative determination of pH, Partial Pressure of Carbon Dioxide (pCO2) and Partial Pressure of Oxygen (pO2) in heparinized arterial and venous whole blood.
pH, pCO2 and pO2 Measurements are used in the diagnosis and treatment of life-threatening acid base disturbances.
The Stat Profile Prime Plus Analyzer System is a low cost, low maintenance analyzer for hospital laboratory and point-of-care settings. It consists of the analyzer, sensor cartridges, and thermal paper for an onboard printer. Optionally, it provides for reading of barcode labels (such as operator badges and data sheets).
The Stat Profile Prime Plus Analyzer has slots to accommodate two sensor cartridges (Primary and Auxiliary). The analyzer will determine the configuration of the system by detecting which sensor cards are installed.
As with the predicate, the Stat Profile Prime Plus Analyzer is a blood gas, co-oximetry, electrolyte, chemistry, and hematology analyzer with an enhanced test menu and multiple quality control options. Both traditional internal and external quality control is available, as well as an on-board Quality Management System (QMS), and an electronic monitoring approach that insures the analyzer is working properly at all times.
The Stat Profile Prime Plus Analyzer accepts samples from syringes and open tubes. The minimum sample size for analysis is 135 µL.
Sample collection, preparation and application to the same as for the previously cleared predicate. The end user can select which analytes are to be tested in the panel.
Here's a breakdown of the acceptance criteria and the study proving the device meets them, based on the provided FDA 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly defined by the demonstration of "substantial equivalence" to the predicate device (Nova Stat Profile pHOx Ultra Analyzer System and K173797 - Stat Profile Prime Plus Analyzer System). The performance of the proposed device is compared to the predicate device and established CLSI guidelines for method comparison and imprecision.
| Criterion Type | Acceptance Criteria (Implicitly from CLSI/Substantial Equivalence) | Reported Device Performance (Stat Profile Prime Plus Analyzer) |
|---|---|---|
| Method Comparison (POC vs Lab) | Agreement between POC measurements and laboratory measurements for pH, pCO2, and pO2, demonstrating substantial equivalence to the predicate and clinical acceptability. | pH: N=432, Range 6.832 - 7.931, Slope 0.9930, Intercept 0.0500, r 0.9976. 95% CI of Bias: MDL (7.1-7.6) for Lower Limit (7.099, 7.595) and Upper Limit (7.102, 7.601) |
| pO2: N=432, Range 11.5 - 555.2, Slope 1.0109, Intercept -1.5391, r 0.9989. 95% CI of Bias: MDL (40-160) for Lower Limit (38.4, 159.7) and Upper Limit (40.6, 160.7) | ||
| pCO2: N=428, Range 14.0 - 199.2, Slope 0.9848, Intercept 0.9958, r 0.9963. 95% CI of Bias: MDL (20-75) for Lower Limit (19.6, 74.5) and Upper Limit (20.9, 75.2) | ||
| Total Imprecision | Acceptable Total SD and %CV for pH, pCO2, and pO2 across multiple levels of quality control materials and different POC personnel, according to CLSI EP5-A2T. | Level 1 (pH 7.223, pCO2 60.0 mmHg, pO2 76.5 mmHg): pH Total SD 0.008; pCO2 Total SD 3.6, %CV 5.9; pO2 Total SD 2.4, %CV 3.1 |
| Level 2 (pH 7.428, pCO2 37.2 mmHg, pO2 112.2 mmHg): pH Total SD 0.006; pCO2 Total SD 2.3, %CV 6.1; pO2 Total SD 3.0, %CV 2.6 | ||
| Level 3 (pH 7.627, pCO2 20.1 mmHg, pO2 148.9 mmHg): pH Total SD 0.008; pCO2 Total SD 1.0, %CV 4.8; pO2 Total SD 3.4, %CV 2.3 | ||
| Within-Run Whole Blood Precision | Acceptable Within-Run SD and %CV for pH, pCO2, and pO2 using fresh, native whole blood samples by POC operators, demonstrating consistent performance in replicate measurements. | pH: SD values ranging from 0.003 to 0.011 across 5 samples. |
| pCO2 (mmHg): %CV values ranging from 0.70% to 1.62% across 5 samples. | ||
| pO2 (mmHg): %CV values ranging from 0.80% to 4.73% across 5 samples. (Specific mean, SD, %CV provided for each of the 5 samples in Table 3) |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Method Comparison:
- N = 432 for pH and pO2 (venous & arterial whole blood specimens combined)
- N = 428 for pCO2 (venous & arterial whole blood specimens combined)
- Sample Size for Total Imprecision: 40 runs (duplicate measurements each day for 20 days) for each of 3 levels of quality control materials.
- Sample Size for Within-Run Whole Blood Precision: 10 replicate measurements for each of 5 different native whole blood samples at each site.
- Data Provenance: The studies were conducted at 3 Point-of-Care (POC) sites including a Cardiothoracic Intensive Care Unit (CTICU), an Emergency Department (ED), and a Respiratory Therapy Lab (RT). The data provenance refers to real-world samples tested by clinical staff in typical POC settings. The report does not specify the country of origin, but given it's an FDA submission, it's typically understood to be within the U.S.
- Nature of Data: The method comparison used "discarded blood gas specimens" and "quality control materials" in addition to "fresh, native whole blood samples" for within-run precision. This indicates retrospective usage of discarded patient samples and prospective collection for precision studies.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The ground truth for the method comparison study was established by "laboratory measurements" (presumably by a predicate or established laboratory analyzer). The document does not specify the number of experts or their qualifications who performed these laboratory measurements. The term "POC personnel" refers to the users of the device under test, not the ground truth establishment.
4. Adjudication Method for the Test Set
The document does not describe any specific "adjudication method" in the sense of multiple experts reviewing results and reaching a consensus. For method comparison studies of this type (quantitative measurements), the reference method (laboratory measurement) typically serves as the "ground truth" against which the new device's performance is compared, using statistical methods (slope, intercept, correlation, bias). No expert adjudication is typically involved beyond ensuring the reference method itself is properly calibrated and operated.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not explicitly done as described in the context of human readers improving with AI assistance. This device is an analyzer, not an AI-assisted diagnostic tool that interprets images or signals requiring human interpretation. The study involved different POC personnel operating the device, which is a form of multi-user testing to assess "imprecision performance" in a real-world setting, but it's not an MRMC study comparing human performance with and without AI.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, the device operates in a standalone manner to measure pH, pCO2, and pO2. The "Point-of-Care (POC) study" assessed the device's performance when operated by healthcare professionals in clinical settings, but the device itself generates the quantitative measurements automatically. The "bench testing" mentioned, performed prior to the POC study, also represents standalone performance. The values in the tables are direct measurements from the device, not interpretations aided by humans.
7. The Type of Ground Truth Used
- For Method Comparison Studies: The ground truth was established by "laboratory measurements" using presumably a reference laboratory analyzer or the predicate device.
- For Imprecision Performance: The ground truth was based on the expected values of the "quality control materials" used.
- For Within-Run Whole Blood Precision: The study evaluated the device's consistency when repeatedly measuring "fresh, native whole blood samples", where the ground truth is simply the intrinsic value of the sample, and the measurement aims to show reproducibility.
8. The Sample Size for the Training Set
This document only describes performance testing for regulatory submission (510(k)). It does not mention or provide details about a "training set" as would be relevant for machine learning algorithms. This device is a diagnostic instrument based on established electrochemical principles, not an AI/ML device that requires a training set in the conventional sense.
9. How the Ground Truth for the Training Set was Established
As no training set is described for this type of device, this question is not applicable.
§ 862.1120 Blood gases (P
CO2 , PO2 ) and blood pH test system.(a)
Identification. A blood gases (PCO2 , PO2 ) and blood pH test system is a device intended to measure certain gases in blood, serum, plasma or pH of blood, serum, and plasma. Measurements of blood gases (PCO2 , PO2 ) and blood pH are used in the diagnosis and treatment of life-threatening acid-base disturbances.(b)
Classification. Class II.