(269 days)
The i-STAT CHEM8+ cartridge with the i-STAT 1 System is in the in vitro quantification of total carbon dioxide in arterial or venous whole blood in point of care or clinical laboratory settings.
Carbon dioxide measurements are used in the diagnosis, monitoring, and treatment of numerous potentially serious disorders associated with changes in body acid-base balance.
The i-STAT CHEM8+ test cartridge contains test reagents to analyze whole blood at the point of care or in the clinical laboratory for total carbon dioxide (TCO2). The test is contained in a single-use, disposable cartridge. Cartridges require two to three drops of whole blood which are typically applied to the cartridge using a transfer device.
The i-STAT 1 Analyzer is a handheld, in vitro diagnostic analytical device designed to run only i-STAT test cartridges. The instrument interacts with the cartridge to move fluid across the sensors and generate a quantitative result (within approximately 2 minutes).
The i-STAT 1 System is comprised of the i-STAT 1 analyzer, the i-STAT test cartridges and accessories (i-STAT 1 Downloader/Recharger, electronic simulator and portable printer). The system is designed for use by trained medical professionals at the patient point of care or in the clinical laboratory and is for prescription use only.
The provided document is a 510(k) Summary for the Abbott Point of Care i-STAT CHEM8+ cartridge with the i-STAT 1 System, which performs in vitro quantification of total carbon dioxide (TCO2) in whole blood.
The acceptance criteria for the device are implicitly demonstrated through the performance characteristics presented, primarily focusing on precision, linearity, limit of quantitation (LoQ), and a method comparison study with a predicate device. The study aims to demonstrate substantial equivalence to the predicate device, SYNCHRON Systems TCO2 Reagent on UniCel DxC 600/800 SYNCHRON Clinical System (K042291).
Here's a breakdown of the requested information:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" in a table format with specific numerical targets. Instead, performance is presented against standard clinical laboratory guideline (CLSI) expectations and compared to a predicate device. The "acceptance" can be inferred from the reported results meeting generally accepted analytical performance standards for clinical assays and demonstrating substantial equivalence to the predicate.
For this response, I will interpret "acceptance criteria" as the performance metrics evaluated and "reported device performance" as the results obtained from the study.
| Performance Metric | Implied Acceptance Criteria (based on CLSI guidelines and predicate comparison) | Reported Device Performance (i-STAT TCO2) |
|---|---|---|
| Precision (Aqueous Materials - Total Precision %CVT) | Generally low %CV for good precision | Level 1 (12.2 mmol/L): 2.4% |
| Level 2 (18.2 mmol/L): 1.7% | ||
| Level 3 (23.6 mmol/L): 2.7% | ||
| Level 4 (31.8 mmol/L): 4.3% | ||
| Level 5 (44.3 mmol/L): 2.1% | ||
| Precision (Whole Blood - Venous %CV) | Generally low %CV for good precision, especially at medical decision levels | 7-15 mmol/L: 5.1% |
| 15-25 mmol/L: 3.1% | ||
| 25-35 mmol/L: 2.3% | ||
| 35-47 mmol/L: 2.6% | ||
| Precision (Whole Blood - Arterial %CV) | Generally low %CV for good precision, especially at medical decision levels | 14-15 mmol/L: 4.0% |
| 15-25 mmol/L: 2.3% | ||
| 25-35 mmol/L: 1.9% | ||
| 35-50 mmol/L: 2.2% | ||
| Linearity (Regression for TCO2) | Slope close to 1, Intercept close to 0, R² close to 1 across the reportable range | Slope: 1.0281 |
| Intercept: -0.1259 | ||
| R²: 0.99379 | ||
| Range Tested: 4 - 52 mmol/L (Reportable Range: 5 - 50 mmol/L) | ||
| Limit of Quantitation (LoQ) | LoQ should be at or below the lower limit of the reportable range | LoQ: 4 mmol/L (below reportable range of 5 mmol/L) |
| Interference | No interference when the difference between spiked and control samples is ≤ 4 mmol/L or 10% of the mean TCO2 result (whichever is greater) | None of the tested substances (Bilirubin, Hemoglobin, Thiopental, Triglyceride, Intralipid) were found to interfere. |
| Method Comparison (Combined Venous & Arterial) | Passing-Bablok regression with slope close to 1, intercept close to 0, and high correlation (r close to 1) when compared to predicate device | N: 294 |
| Slope: 1.04 | ||
| Intercept: 0.17 | ||
| r: 0.97 | ||
| Method Comparison (Venous Whole Blood) | Passing-Bablok regression with slope close to 1, intercept close to 0, and high correlation (r close to 1) when compared to predicate device | N: 183 |
| Slope: 1.05 | ||
| Intercept: -0.01 | ||
| r: 0.98 | ||
| Method Comparison (Arterial Whole Blood) | Passing-Bablok regression with slope close to 1, intercept close to 0, and high correlation (r close to 1) when compared to predicate device | N: 111 |
| Slope: 1.03 | ||
| Intercept: 1.07 | ||
| r: 0.94 |
2. Sample Size Used for the Test Set and Data Provenance
- Precision (Whole Blood):
- Test Set Size: 279 samples (178 venous, 101 arterial).
- Data Provenance: Not explicitly stated as retrospective or prospective, but the phrasing "collected across three point of care sites" suggests these were fresh clinical samples collected for the purpose of the study (prospective or near-patient testing).
- Linearity (Whole Blood):
- Test Set Size: Not explicitly stated as a single number of samples, but involved preparing "whole blood samples of varying analyte levels that spanned the reportable range of the test."
- Data Provenance: Implied to be laboratory-prepared whole blood samples, likely prospective.
- Limit of Quantitation (LoQ):
- Test Set Size: Not explicitly stated as a single number of samples, but used "whole blood that was altered to low TCO2." The study was conducted over four (4) days using two (2) cartridge lots.
- Data Provenance: Implied to be laboratory-prepared whole blood samples, likely prospective.
- Interference:
- Test Set Size: Not explicitly stated as a single number of samples, but involved "whole blood test samples based on CLSI EP07-A2."
- Data Provenance: Implied to be laboratory-prepared whole blood samples, likely prospective.
- Method Comparison:
- Test Set Size: 294 specimens (183 lithium heparin venous whole blood, 111 lithium heparin arterial whole blood). 21 of these (7.14%) were "contrived" (meaning altered or spiked samples to extend the range).
- Data Provenance: Collected across three point of care sites, suggesting prospective clinical samples. The "contrived" samples are laboratory-prepared.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This type of information is generally not applicable for quantitative clinical chemistry assays like the one described. The "ground truth" for TCO2 is established by a reference method or a predicate device. In this case, the predicate device (SYNCHRON Systems TCO2 Reagent on UniCel DxC 600/800 SYNCHRON Clinical System) serves as the comparator or "reference method" for the method comparison study. Clinical experts are not typically involved in establishing the numerical ground truth for such analytes; rather, laboratory professionals operating validated equipment do.
4. Adjudication Method for the Test Set
Not applicable. Adjudication methods (like 2+1 or 3+1) are typically used in image-based diagnostic studies where human experts individually interpret results and a consensus process is needed to establish ground truth or resolve discrepancies. For this quantitative clinical chemistry device, the comparison is directly between numerical results from the candidate device and the predicate device/reference method.
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 device is a fully automated quantitative clinical chemistry analyzer. There are no "human readers" involved in interpreting results from the device in a diagnostic context that would require an MRMC study or AI assistance. The device provides a numerical output for TCO2.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) Was Done
Yes, the studies presented are all standalone performance evaluations of the i-STAT CHEM8+ cartridge with the i-STAT 1 System. The device provides a direct quantitative measurement of TCO2 in whole blood without the need for human interpretation or further input once the sample is loaded and the test initiated. The precision, linearity, LoQ, interference, and method comparison studies evaluate the algorithm/device performance directly.
7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)
The ground truth for the method comparison study was established by comparison to a legally marketed predicate device, the SYNCHRON Systems TCO2 Reagent on UniCel DxC 600/800 SYNCHRON Clinical System. For analytical performance studies (precision, linearity, LoQ, interference), the ground truth is based on the expected values of control materials or the known concentrations of prepared samples, often traceable to a reference measurement procedure (as mentioned for "Traceability: IFCC Reference Measurement Procedure" in Section 6, though this is for the candidate device, implying its own internal traceability).
8. The Sample Size for the Training Set
Not applicable. This device is a quantitative clinical chemistry analyzer, not a machine learning or AI-based diagnostic tool that typically requires a large "training set" in the conventional sense of AI development. While there is likely internal development and calibration data, the document does not refer to a distinct "training set" for an algorithm in the way it is discussed for AI/ML devices. The "training" for such devices often refers to rigorous calibration and verification procedures in the manufacturing process.
9. How the Ground Truth for the Training Set Was Established
Not applicable for the reasons stated in point 8.
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February 7, 2020
Abbott Point of Care Inc. Susan Tibedo Director, Regulatory Affairs 400 College Road East Princeton, NJ 08540
Re: K191298
Trade/Device Name: i-STAT CHEM8+ cartridge with the i-STAT 1 System Regulation Number: 21 CFR 862.1160 Regulation Name: Bicarbonate/carbon dioxide test system Regulatory Class: Class II Product Code: JFL Dated: January 6, 2020 Received: January 7, 2020
Dear Susan Tibedo:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's
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requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Kellie B. Kelm, Ph.D. Acting Director Division of Chemistry and Toxicology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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Indications for Use
510(k) Number (if known) K191298
Device Name
i-STAT CHEM8+ cartridge with the i-STAT 1 System
Indications for Use (Describe)
The i-STAT CHEM8+ cartridge with the i-STAT 1 System is in the in vitro quantification of total carbon dioxide in arterial or venous whole blood in point of care or clinical laboratory settings.
Carbon dioxide measurements are used in the diagnosis, monitoring, and treatment of numerous potentially serious disorders associated with changes in body acid-base balance.
Type of Use (Select one or both, as applicable)
Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)
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510(k) Summary
The information in this 510(k) summary is being submitted in accordance with the requirements of 21 CFR 807.92.
| 1. | Submitter Information | |
|---|---|---|
| Owner | Abbott Point of Care Inc.400 College Road EastPrinceton, NJ 08540 | |
| Contact | Primary: Susan TibedoDirector Regulatory Affairssusan.tibedo@abbott.comPhone: 609-454-9360Secondary: Maria FigueroaManager Regulatory Affairsmaria.l.figueroa@abbott.comPhone: 609-454-9271 | |
| Date Prepared | February 5, 2020 | |
| 510k Number | K191298 |
2. Device Information
Proprietary Name i-STAT CHEM8+ Cartridge with i-STAT 1 Analyzer
Common Name Chemistry test, analyzer, handheld
| Productcode | Device Classificationname | RegulationNumber | Class | Panel |
|---|---|---|---|---|
| JFL | Bicarbonate, CarbonDioxide Test System | 862.1160 | II | Clinical Chemistry |
3. Predicate Device
Proprietary Name SYNCHRON Systems TCO2 Reagent on UniCel DxC 600/800 SYNCHRON Clinical System
510(k) Number K042291
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| Productcode | Device Classificationname | RegulationNumber | Class | Panel |
|---|---|---|---|---|
| JFL | Bicarbonate, CarbonDioxide Test System | 862.1160 | II | Clinical Chemistry |
4. Device Description
The i-STAT CHEM8+ test cartridge contains test reagents to analyze whole blood at the point of care or in the clinical laboratory for total carbon dioxide (TCO2). The test is contained in a single-use, disposable cartridge. Cartridges require two to three drops of whole blood which are typically applied to the cartridge using a transfer device.
The i-STAT 1 Analyzer is a handheld, in vitro diagnostic analytical device designed to run only i-STAT test cartridges. The instrument interacts with the cartridge to move fluid across the sensors and generate a quantitative result (within approximately 2 minutes).
The i-STAT 1 System is comprised of the i-STAT 1 analyzer, the i-STAT test cartridges and accessories (i-STAT 1 Downloader/Recharger, electronic simulator and portable printer). The system is designed for use by trained medical professionals at the patient point of care or in the clinical laboratory and is for prescription use only.
5. Intended Use Statement
The i-STAT CHEM8+ cartridge with the i-STAT 1 System is intended for use in the in vitro quantification of total carbon dioxide in arterial or venous whole blood in point of care or clinical laboratory settings.
Carbon dioxide measurements are used in the diagnosis, monitoring, and treatment of numerous potentially serious disorders associated with changes in body acid-base balance.
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| Feature orCharacteristic | PredicateSYNCHRON Systems TCO2Reagent on UniCel DxC600/800 SYNCHRON ClinicalSystem (K042291) | Candidatei-STAT TCO2 Test with i-STAT 1System |
|---|---|---|
| Intended Use | The CO2 test is intended for thequantitative determination ofcarbon dioxide in human serumor plasma.Carbon dioxide measurementsare used in the diagnosis andtreatment of numerouspotentially serious disordersassociated with changes in bodyacid-base balance. | The i-STAT CHEM8+ cartridge withthe i-STAT 1 System is intended foruse in the in vitro quantification oftotal carbon dioxide in arterial orvenous whole blood in point of careor clinical laboratory settings.Carbon dioxide measurements areused in the diagnosis, monitoring,and treatment of numerouspotentially serious disordersassociated with changes in bodyacid-base balance. |
| ReportableRange | 5-50 mmol/L (Serum or Plasma) | 5-50 mmol/L (mEq/L) |
| Sample Type | Serum or plasma | Arterial or venous whole blood |
| Sample Volume | 0.5 mL (500 μL) | 95 μL |
| Preparation | Sample tubes prepared and thenprocessed within analyzer | Ready to Use |
| Traceability | Unknown traceability reference | IFCC Reference MeasurementProcedure |
| Calibration | Must be conducted every 24hours and with each newreagent | 1-point on-board contained within thecartridge |
| Time to Test(SampleStability) | Serum or plasma: Within 8 hoursat room temperature, or up to 48hours if stored at +2°C to +8°C | Heparinized samples: within 10minutes of collection |
| Principle ofMeasurement | Ion selective electrode | Ion selective electrode |
| Reagent Format | Reagent handling system, storedwithin analyzer | Cartridge |
| Reagent Storageand Stability | Room temperature | 2°C to 8°C (35-46°F) |
| Analyzer Type | Floor Model | Handheld |
-
- Summary Comparison of Technological Characteristics
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7. Performance Characteristics
Analytical Performance
a. Precision
Precision 20 days (Aqueous Materials)
The precision of the i-STAT TCO2 test on the i-STAT 1 Wireless Analyzer was evaluated using 5 levels of aqueous materials. This 20-day multi-day precision testing was based on CLSI document EP05-A3: Evaluation of Precision of Quantitative Measurement Procedures: Approved Guideline-Third Edition. The study was conducted using multiple instruments and one test cartridge lot over 20 days at one site. Total precision ( 'within-laboratory', Sr), within-run, (Sr), between-run, (Sr) and between-day, (Saa) were estimated for each level. The results of the 20-day precision study are shown in Table 1.
| Table 1: 20-Day Precision of i-STAT TCO2 test on the i-STAT 1 Analyzer | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Analyte | Fluid Level | N | Mean/Median | Total | Repeatability | Between-Run | Between-Day | ||||
| ST | %CVT | Sr | %CVr | Srr | %CVrr | Sdd | %CVdd | ||||
| TCO2mmol/L | CV L1 | 81 | 12.2 | 0.29 | 2.4 | 0.26 | 2.1 | 0.08 | 0.7 | 0.08 | 0.7 |
| CV L2 /Control L1* | 80 | 18.2 | 0.31 | 1.7 | 0.30 | 1.6 | 0.07 | 0.4 | 0.07 | 0.4 | |
| CV L3 /Control L2* | 80 | 23.6 | 0.64 | 2.7 | 0.58 | 2.5 | 0.21 | 0.9 | 0.15 | 0.6 | |
| CV L4 /Control L3*, | 80 | 31.8 | 1.36 | 4.3 | 1.26 | 4.0 | 0.20 | 0.6 | 0.49 | 1.5 | |
| CV L4B | 81 | 44.3 | 0.93 | 2.1 | 0.69 | 1.6 | 0.32 | 0.7 | 0.53 | 1.2 |
- The aqueous control materials (Control L1, L2, L3) are also used as the middle levels of the calibration verification set (CV L2, CV L3, CV L4). The aqueous fluids are the same.
Precision (Whole Blood)
A whole blood repeatability analysis was conducted using the data collected across three point of care sites. Two hundred and seventy-nine samples (178 venous and 101 arterial) were measured in duplicate. The mean values for each sample were divided into four subintervals for each sample type taking into consideration the medical decision levels of 6, 20, and 33 mmol/L.
The results are provided in Table 2 and Table 3 below:
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| Table 2: Venous whole blood | ||||||||
|---|---|---|---|---|---|---|---|---|
| Sample Range(mmol/L) | N | Mean(mmol/L) | SD | CV (%) | ||||
| 7 - 15 | 15 | 9.43 | 0.483 | 5.1 | ||||
| 15 - 25 | 61 | 21.25 | 0.665 | 3.1 | ||||
| 25 - 35 | 82 | 27.72 | 0.625 | 2.3 | ||||
| 35 - 47 | 20 | 39.33 | 1.037 | 2.6 |
| Table 3: Arterial whole blood | ||||
|---|---|---|---|---|
| Sample Range(mmol/L) | N | Mean(mmol/L) | SD | CV (%) |
| 14 - 15 | 3 | 14.33 | 0.577 | 4.0 |
| 15 - 25 | 46 | 22.29 | 0.521 | 2.3 |
| 25 - 35 | 48 | 28.10 | 0.520 | 1.9 |
| 35 - 50 | 4 | 39.50 | 0.866 | 2.2 |
b. Linearity
The study was designed based on CLSI EP06-A: Evaluation of the Linearity of Quantitative Measurement Procedures.
The linearity of the i-STAT TCO2 test on the i-STAT 1 Analyzer was evaluated by preparing whole blood samples of varying analyte levels that spanned the reportable range of the test. The i-STAT TCO2 test demonstrated linearity over the reportable range 5 - 50 mmol/L. Regression summary of the TCO2 response (in mmol/L) versus the concentration of the whole blood samples of varying analyte levels is provided in Table 4.
| Table 4: Regression Summary for the i-STAT TCO2 test on the i-STAT 1 Analyzer | |||||
|---|---|---|---|---|---|
| i-STAT Test(mmol/L) | ReportableRange (mmol/L) | Range Tested(mmol/L) | Slope | Intercept | R2 |
| TCO2 | 5 - 50 | 4 - 52 | 1.0281 | -0.1259 | 0.99379 |
c. Limit of Quantitation (LoQ)
The study was based on the CLSI EP17-A2: Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures; Approved Guideline-Second Edition.
The LoQ of the i-STAT TCO2 test was evaluated on the i-STAT 1 Analyzer using whole blood that was altered to low TCO2 (≤ 5.0 mmol/L). The study was conducted over four (4) days using two (2) cartridge lots. The LoQ for the i-STAT TCO2 test was determined to be 4 mmol/L, which is below the lower limit of the i-STAT TCO2 test reportable range (5 - 50 mmol/L).
d. Interference
The interference performance of the i-STAT TCO2 test on the i-STAT 1 Analyzer was evaluated using whole blood test samples based on CLSI EP07-A2: Interference
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Testing in Clinical Chemistry; Approved Guideline - Second Edition. The effect of each substance at each TCO2 level was evaluated by comparing the performance of a test sample spiked to a high concentration of the substance and a control sample spiked with an equal volume of solvent. A substance was identified as an interferent if the difference between the spiked test sample and the control was greater than the allowable error defined as the greater of 4 mmol/L or 10% of the mean TCO2 result for the control sample. None of the substances evaluated (See Table 5) were found to interfere with the i-STAT TCO2 test.
| Table 5: List of Substances and Test Concentrations | ||
|---|---|---|
| Substance | Test Concentration* | |
| as specified | mg/dL | |
| Bilirubin | 342 $\mu$ mol/L | 20 |
| Hemoglobin | 2 g/L | 200 |
| Thiopental | 248 $\mu$ mol/L | 6.01 |
| Triglyceride | 37 mmol/L | 3233.8 |
| Intralipid | N/A | 7092 |
*The molecular weight of the substance tested was used to convert the test concentration from mmol/L to mg/dL. The molecular weight of each substance could vary depending on the form chosen.
Comparison Study
e. Method Comparison with Predicate Device
The accuracy of the TCO2 assay on the i-STAT CHEM8+ (blue) cartridge on the i-STAT 1 Analyzer was evaluated by a method comparison study for agreement with the predicate device. The study was conducted across three point of care sites. A total of 294 specimens, 183 lithium heparin venous whole blood specimens and 111 lithium heparin arterial whole blood specimens were tested. Twenty-one of 294 samples (7.14%) were contrived.
| Table 6: Passing-Bablok Regression Summary of Venous and Arterial DataCombined | ||||
|---|---|---|---|---|
| i-STAT Test | N | Slope | Intercept | r |
| TCO2 | 294 | 1.04 | 0.17 | 0.97 |
The data was analyzed separately for venous whole blood and arterial whole blood samples by Passing-Bablok regression analysis comparing the first replicate of the candidate device results to the singlicate result of lithium heparin plasma samples on the predicate device. Results are presented in Table 7 and Table 8 below.
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| Site | N | Sample Range Tested(mmol/L) | RegressionEquation | r |
|---|---|---|---|---|
| 1 | 23 | 19 – 33 | y = 1.83 + 0.98x | 0.87 |
| 2 | 50 | 9 – 41 | y = 0.00 + 1.00x | 0.98 |
| 3 | 93 | 15 – 46 | y = 0.00 + 1.08x | 0.98 |
| combined | 183* | 6 – 46 | y = -0.01 + 1.05x | 0.98 |
- Includes 17 contrived specimens.
| Site | N | Sample Range Tested (mmol/L) | Regression Equation | r |
|---|---|---|---|---|
| 1 | 53 | 14 – 39 | y = 3.58 + 0.97x | 0.96 |
| 2 | 48 | 15 – 50 | y = 1.00 + 1.00x | 0.96 |
| 3 | 6 | 23 – 29 | N/A | |
| combined | 111* | 7 – 50 | y = 1.07 + 1.03x | 0.94 |
- Includes 4 contrived specimens.
8. Conclusion
The results of these studies demonstrate that performance of the i-STAT CHEM8+ TCO2 test with the i-STAT 1 System are substantially equivalent to the comparative method.
§ 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.