(267 days)
No
The summary describes a standard in vitro diagnostic device that uses electrochemical sensors to measure blood gas parameters. There is no mention of AI, ML, or any computational methods beyond standard analytical calculations. The performance studies focus on traditional analytical validation metrics.
No.
The device is an in vitro diagnostic (IVD) medical device used for quantifying H, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) in whole blood, which are measurements used in diagnosis, monitoring, and treatment, but the device itself does not directly provide therapy.
Yes
The "Intended Use / Indications for Use" section explicitly states that "pH, PO2, and PCO2 measurements are used in the diagnosis, monitoring, and treatment of respiratory, metabolic and acid-base disturbances." Additionally, the "Device Description" section labels it an "in vitro diagnostic (IVD) medical device."
No
The device description clearly states that the i-STAT 1 System includes a portable blood analyzer (hardware) and single-use disposable test cartridges (hardware with sensors and reagents). The software is part of a system that relies on these physical components to function.
Yes, the i-STAT CG8+ cartridge with the i-STAT 1 System is an IVD (In Vitro Diagnostic) device.
Here's why, based on the provided text:
- Explicit Statement: The "Device Description" section explicitly states: "The i-STAT 1 System is an in vitro diagnostic (IVD) medical device intended for the quantitative determination of various clinical chemistry tests contained within i-STAT cartridges using whole blood."
- Intended Use: The "Intended Use / Indications for Use" section describes the device's purpose as "in the in vitro quantification of H, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) in arterial, venous, or capillary whole blood". "In vitro" means "in glass" or "outside the body," which is a key characteristic of IVD devices.
- Sample Type: The device analyzes "whole blood," which is a biological specimen commonly used in IVD testing.
- Clinical Purpose: The measurements are used "in the diagnosis, monitoring, and treatment of respiratory, metabolic and acid-base disturbances," indicating a clinical diagnostic purpose.
- Care Setting: The device is intended for use in "point of care or clinical laboratory settings," typical environments for IVD testing.
- Prescription Use: The device is for "prescription use only," which is common for IVD devices used in clinical settings.
All these points align with the definition and characteristics of an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
The i-STAT CG8+ cartridge with the i-STAT 1 System is intended for use in the in vitro quantification of H, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) in arterial, venous, or capillary whole blood in point of care or clinical laboratory settings.
pH, PO2, and PCO2 measurements are used in the diagnosis, monitoring, and treatment of respiratory, metabolic and acid-base disturbances.
Product codes
CHL
Device Description
The i-STAT CG8+ cartridge is used with the i-STAT 1 analyzer as part of the i-STAT 1 System and contains test reagents to measure pH, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) in arterial, venous or capillary whole blood.
The i-STAT 1 System is an in vitro diagnostic (IVD) medical device intended for the quantitative determination of various clinical chemistry tests contained within i-STAT cartridges using whole blood. The i-STAT 1 System consists of a portable blood analyzer (i-STAT 1 analyzer), single-use disposable test cartridges (i-STAT cartridges), liquid quality control and calibration verification materials, and accessories (i-STAT 1 Downloader/Recharger, i-STAT Electronic Simulator and i-STAT 1 Printer). The i-STAT 1 System, including the i-STAT CG8+ cartridge, is designed for use by trained medical professionals in point of care or clinical laboratory settings and is for prescription use only.
The i-STAT CG8+ cartridge contains the required sensors, a fluid pack (calibrant pouch), a sample entry well and closure, fluid channels, waste chamber, and the necessary mechanical features for controlled fluid movement within cartridge. The i-STAT cartridge format allows all the tests in the cartridge to be performed simultaneously. All the test steps and fluid movement occur within the i-STAT CG8+ cartridges require two to three drops of whole blood applied to the cartridge using a transfer device by the trained user before the cartridge is placed within the analyzer.
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 i-STAT CG8+ cartridge to move fluid across the sensors and generate a quantitative result (within approximately 2 minutes).
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
trained medical professionals in point of care or clinical laboratory settings and is for prescription use only.
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies
Analytical Performance - Precision/Reproducibility:
- 20 days (Aqueous materials): Evaluated using five (5) levels of aqueous material. Study conducted using multiple analyzers and one (1) test cartridge lot over 20 days at one site. N=80 for each fluid level for pH, PO2, and PCO2. Results showed repeatability, between-run, between-day, and within-laboratory precision.
- Multi-site and operator-to-operator precision (Aqueous materials): Performed at three (3) sites using a panel of aqueous solutions containing five (5) levels of pH, PO2, and PCO2. At each site, each level was tested once a day by two (2) operators for five (5) days on six (6) i-STAT 1 analyzers using i-STAT CG8+ cartridges. N=90 or 96 for most fluid levels. Components calculated were within-run, between-day, between-operator, within-site (total), between-site, and overall variance.
- Precision (Whole Blood): Evaluated using arterial, venous, and capillary whole blood specimens collected with lithium heparin. Assessed using duplicate test results collected across multiple point of care sites. Sample sizes varied by sample type and analyte range (e.g., pH: N=14 to 108; PO2: N=2 to 136; PCO2: N=2 to 97). For capillary whole blood, two individual fingersticks were collected independently by two operators into two separate capillary tubes and tested on two i-STAT CG8+ cartridges.
Analytical Performance - Linearity/Assay Reportable Range:
- Linearity: Evaluated by preparing whole blood samples of varying analyte levels for each i-STAT test. Demonstrated linearity over the reportable range.
- pH: Range Tested 6.4290 – 7.8522, Slope 1.011, Intercept -0.098, R2 0.9994
- PO2: Range Tested 4.4 – 700.0 mmHg, Slope 0.977, Intercept 1.062, R2 0.9956
- PCO2: Range Tested 2.40 – 148.38 mmHg, Slope 1.029, Intercept -1.144, R2 0.9991
Analytical Performance - Detection Limit:
- Limit of Quantitation (LoQ): Evaluated using two (2) i-STAT CG8+ cartridge lots and whole blood altered to low analyte levels.
- pH: Determined LoQ 6.464 pH units (Lower limit of reportable range 6.500)
- PO2: Determined LoQ 5 mmHg (Lower limit of reportable range 5)
- PCO2: Determined LoQ 3.2 mmHg (Lower limit of reportable range 5.0)
Analytical Performance - Analytical Specificity (Interference):
- Evaluated using whole blood samples to assess the effect of potentially interfering substances at toxic/pathological concentrations. A substance was identified as an interferent if the difference between control and test samples was outside of allowable error. Acetaminophen, Atracurium, Bilirubin, Calcium, Ethanol, Hemoglobin, Ibuprofen, Intralipid 20%, Morphine, Potassium, Sodium, Thiopental, and Triglyceride were tested and found to cause no interference for pH, PO2, and PCO2.
Other Sensitivity Studies - Altitude:
- Evaluated performance at approximately 10,000 feet above sea level using whole blood samples across reportable ranges. Results compared to a comparator device (i-STAT CG4+ (blue) cartridges on i-STAT 1 analyzer). Passing-Bablok regression analyses were performed.
- pH: Correlation Coefficient (r) = 1.00, Slope = 0.99
- PO2: Correlation Coefficient (r) = 1.00, Slope = 1.02
- PCO2: Correlation Coefficient (r) = 1.00, Slope = 0.98
- Key results: Correlation coefficient and slope met acceptance criteria, demonstrating equivalent performance.
Comparison Studies - Method Comparison with Comparator Device:
- Conducted for arterial, venous, and capillary whole blood specimens. Lithium heparin venous and arterial whole blood specimens (N=468 for pH, N=461 for PO2, N=465 for PCO2) were evaluated against a comparative method (RAPIDPoint 500/500e). Capillary whole blood specimens (N=195 for pH, N=190 for PO2, N=189 for PCO2) were also evaluated against the comparative method. Passing-Bablok linear regression analysis was performed on pooled data.
- Pooled (Arterial/Venous/Capillary) Results against RAPIDPoint 500/500e:
- pH: N=468, Slope=1.00, Intercept=0.00, r=0.99. Bias at medical decision levels: -0.0040.
- PO2: N=461, Slope=1.03, Intercept=-0.72, r=0.99. Bias at medical decision levels: 0.1 to 0.9.
- PCO2: N=465, Slope=1.08, Intercept=-1.13, r=0.97. Bias at medical decision levels: 1.79 to 4.71.
- Capillary Specimens Only (Native and Contrived) Results:
- pH: N=195, Slope=1.02, Intercept=-0.11, r=0.98. Range 6.619 - 7.772.
- PO2: N=190, Slope=1.02, Intercept=-1.75, r=0.99. Range 12.8 - 652.6.
- PCO2: N=189, Slope=1.09, Intercept=-1.90, r=0.97. Range 9.1 - 124.9.
- Native Capillary Specimens Only - Bias at Medical Decision Levels:
- pH: N=179, Bias -0.0160 to -0.0041.
- PO2: N=175, Bias -1.8 to -0.7.
- PCO2: N=179, Bias 1.17 to 3.36.
- Pooled (Arterial/Venous/Capillary) Results against RAPIDPoint 500/500e:
Comparison Studies - Matrix Equivalence:
- Evaluated performance using non-anticoagulated venous and arterial whole blood specimens compared to samples collected with balanced heparin or lithium heparin anticoagulant. Each specimen tested in duplicate (N=241). Passing-Bablok linear regression analysis was performed.
- pH: r=0.98, Slope=0.97, Intercept=0.19
- PO2: r=0.98, Slope=0.94, Intercept=1.28
- PCO2: r=0.96, Slope=1.02, Intercept=-0.23
Key Metrics
- Precision/Repeatability: SD and %CV values reported across various fluid levels and conditions.
- Linearity: Slope, Intercept, and R2 values.
- Detection Limit: Determined LoQ.
- Interference: Yes/No for specific substances.
- Altitude Study: Correlation Coefficient (r) and Slope.
- Method Comparison: Slope, Intercept, Correlation Coefficient (r), and Bias at Medical Decision Levels.
Predicate Device(s)
Reference Device(s)
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information
Not Found
§ 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.
0
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October 27, 2023
Abbott Point of Care Inc. Jacquelyn Gesumaria Principal Regulatory Affairs Specialist 400 College Road East Princeton, New Jersey 08540
Re: K230285
Trade/Device Name: i-STAT CG8+ cartridge with the i-STAT 1 System Regulation Number: 21 CFR 862.1120 Regulation Name: Blood Gases (PCO2, PO2) And Blood pH Test System Regulatory Class: Class II Product Code: CHL Dated: September 28, 2023 Received: September 28, 2023
Dear Jacquelyn Gesumaria:
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 (the 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 available 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.
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
1
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
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 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 Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safetyreporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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,
Paula V. Caposino -S
Paula Caposino, Ph.D. Acting Deputy Director Division of Chemistry and Toxicology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
2
Indications for Use
510(k) Number (if known) K230285
Device Name i-STAT CG8+ cartridge with the i-STAT 1 System
Indications for Use (Describe)
The i-STAT CG8+ cartridge with the i-STAT 1 System is intended for use in the in vitro quantification of H, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) in arterial, venous, or capillary whole blood in point of care or clinical laboratory settings.
pH, PO2, and PCO2 measurements are used in the diagnosis, monitoring, and treatment of respiratory, metabolic and acid-base disturbances.
| 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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3
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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.
I. SUBMITTER INFORMATION
| Owner | Abbott Point of Care Inc.
400 College Road East
Princeton, NJ 08540 |
|---------------|------------------------------------------------------------------------------------------------|
| Contact | Primary: Jacquelyn Gesumaria
Principal Regulatory Affairs Specialist
Phone: 609-454-9384 |
| | Secondary: Mojgan Soleimani
Associate Director Regulatory Affairs
Phone: 613-295-0932 |
| Date Prepared | October 27, 2023 |
II. DEVICE INFORMATION
| Proprietary Name | i-STAT CG8+ cartridge with the i-STAT 1 System |
|---|---|
| Common Name | Blood gas test, analyzer, handheld |
| 510(k) Number | K230285 |
| Product Code | Device Classification
Name | Regulation
Number | Class | Panel |
|--------------|----------------------------------|----------------------|-------|--------------------|
| CHL | Electrode, Ion
Specific, pH | 862.1120 | II | Clinical Chemistry |
| CHL | Electrode, Ion
Specific, PCO2 | 862.1120 | II | Clinical Chemistry |
| CHL | Electrode, Ion
Specific PO2 | 862.1120 | II | Clinical Chemistry |
4
III. PREDICATE DEVICE
RAPIDPoint 500e Blood Gas System Proprietary Name
510(k) Number K192240
| Product
Code | Device Classification
Name | Regulation
Number | Class | Panel |
|-----------------|----------------------------------|----------------------|-------|--------------------|
| CHL | Electrode, Ion Specific, pH | 862.1120 | II | Clinical Chemistry |
| CHL | Electrode, Ion Specific,
PCO2 | 862.1120 | II | Clinical Chemistry |
| CHL | Electrode, Ion Specific PO2 | 862.1120 | II | Clinical Chemistry |
IV. DEVICE DESCRIPTION
The i-STAT CG8+ cartridge is used with the i-STAT 1 analyzer as part of the i-STAT 1 System and contains test reagents to measure pH, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) in arterial, venous or capillary whole blood.
The i-STAT 1 System is an in vitro diagnostic (IVD) medical device intended for the quantitative determination of various clinical chemistry tests contained within i-STAT cartridges using whole blood. The i-STAT 1 System consists of a portable blood analyzer (i-STAT 1 analyzer), single-use disposable test cartridges (i-STAT cartridges), liquid quality control and calibration verification materials, and accessories (i-STAT 1 Downloader/Recharger, i-STAT Electronic Simulator and i-STAT 1 Printer). The i-STAT 1 System, including the i-STAT CG8+ cartridge, is designed for use by trained medical professionals in point of care or clinical laboratory settings and is for prescription use only.
The i-STAT CG8+ cartridge contains the required sensors, a fluid pack (calibrant pouch), a sample entry well and closure, fluid channels, waste chamber, and the necessary mechanical features for controlled fluid movement within cartridge. The i-STAT cartridge format allows all the tests in the cartridge to be performed simultaneously. All the test steps and fluid movement occur within the i-STAT CG8+ cartridges require two to three drops of whole blood applied to the cartridge using a transfer device by the trained user before the cartridge is placed within the analyzer.
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 i-STAT CG8+ cartridge to move fluid across the sensors and generate a quantitative result (within approximately 2 minutes).
V. INTENDED USE STATEMENT
The i-STAT CG8+ cartridge with the i-STAT 1 System is intended for use in the in vitro quantification of pH, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) in arterial, venous, or capillary whole blood in point of care or clinical laboratory settings.
pH, PO2, and PCO2 measurements are used in the diagnosis, monitoring, and treatment of respiratory, metabolic and acid-base disturbances.
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VI. SUMMARY COMPARISON OF TECHNOLOGICAL CHARACTERISTICS
| Table 1: Similarities and Differences (Test and Instrument): pH, PO2, and PCO2 in Arterial, Venous, and Capillary Whole Blood | ||
|---|---|---|
| Feature or Characteristic | Candidate Device: | |
| pH, PO2 and PCO2 Tests in the: | ||
| i-STAT CG8+ cartridge | ||
| with the i-STAT 1 System | Predicate Device: | |
| pH, PO2 and PCO2 Tests in the | ||
| Siemens RAPIDPoint 500e | ||
| Blood Gas System | ||
| (K192240) | ||
| Intended Use | The i-STAT CG8+ cartridge with the | |
| i-STAT 1 System is intended for use in | ||
| the in vitro quantification of sodium, | ||
| potassium, ionized calcium, glucose, | ||
| hematocrit, pH, partial pressure of | ||
| oxygen (PO2), and partial pressure of | ||
| carbon dioxide (PCO2) in arterial, | ||
| venous, or capillary whole blood in | ||
| point of care or clinical laboratory | ||
| settings. | ||
| pH, PO2, and PCO2 measurements are | ||
| used in the diagnosis, monitoring, and | ||
| treatment of respiratory, metabolic and | ||
| acid-base disturbances. | The RAPIDPoint 500e Blood Gas System is | |
| intended for in vitro diagnostic use and is | ||
| designed to provide the determination in | ||
| whole blood for the following parameters: | ||
| • Partial pressure of carbon dioxide | ||
| • Partial pressure of oxygen | ||
| • pH | ||
| • Sodium | ||
| • Potassium | ||
| • Ionized Calcium | ||
| • Chloride | ||
| • Glucose | ||
| • Lactate | ||
| • Total Hemoglobin and fractions: FO2Hb, | ||
| FCOHb, FMetHb, FHHb | ||
| • Neonatal Bilirubin |
The RAPIDPoint 500e Blood Gas System is
also intended for in vitro testing of pleural
fluid samples for the pH parameter. The pH
measurement of pleural fluid can be a
clinically useful tool in the management of
patients with parapneumonic effusions. The
following critical value applies to pleural
fluid pH: pH > 7.3 is measured in
uncomplicated parapneumonic effusions. All
pleural fluids with a pH measurement i-STAT CG8+ cartridge
with the i-STAT 1 System | Predicate Device:
pH, PO2 and PCO2 Tests in the
Siemens RAPIDPoint 500e
Blood Gas System
(K192240) |
| Regulation
No. | Same | 862.1120 |
| Reportable
Range | pH
Same | pH
6.500 – 7.800 |
| | PO2
$5-700 mmHg$
$0.7-93.3 kPa$ | pO2
$10.0-700.0 mmHg$
$1.33-93.32 kPa$ |
| | PCO2
$5-130 mmHg$
$0.67-17.33 kPa$ | PCO2
$5.0-200.0 mmHg$
$0.66-26.66 kPa$ |
| Sample Type | Arterial, venous or capillary whole blood | Whole blood (Arterial, Venous and Capillary for all analytes)Pleural Fluid (for pH test only) |
| Sample
Volume | 95 μL | 100 μL |
| Sample
Preparation | Same | Ready to use |
| Sample
collection | Without anticoagulant (for arterial and venous whole blood sample types)With balanced heparin anticoagulant or lithium heparin anticoagulant (for arterial, venous, and capillary whole blood sample types) | With balanced heparin anticoagulant or lithium heparin anticoagulant |
| Traceability | pH
Traceable to NIST SRMs
186-I, 186-II, 185 and 187 | pH
Traceable to NIST SRM 186 reference materials via the IFCC blood reference method. |
| | PO2, PCO2
Traceable to NIST SRMs via commercially available certified specialty medical gas tanks | PO2, PCO2
Traceable to tonometered aqueous standards prepared using NIST traceable temperature and pressure standards and gravimetrically prepared precision gas standards. |
| Calibration | 1-point calibration using reagents contained within cartridge | 1-point, 2-point and full calibration using automated on board reagent |
| Table 1: Similarities and Differences (Test and Instrument): pH, PO2, and PCO2 in Arterial, Venous,
and Capillary Whole Blood | | |
| Feature or
Characteristic | Candidate Device:
pH, PO2 and PCO2 Tests in the:
i-STAT CG8+ cartridge
with the i-STAT 1 System | Predicate Device:
pH, PO2 and PCO2 Tests in the
Siemens RAPIDPoint 500e
Blood Gas System
(K192240) |
| Principle of
Measurement | pH, PCO2: Potentiometric measurement
between active working sensor and
independent reference sensor
PO2: Amperometric measurement of
oxygen reduction current | pH, PCO2: Potentiometric method
PO2: Amperometric measurement |
| Reagent
Format | Same | Cartridge |
| Storage
Conditions | Refrigerated at 2-8°C (35-46°F) until
expiration date
Room Temperature at 18-30°C (64-86°F)
for 2 months | Refrigerated at 2 to 8°C (35 to 46°F) until
stated "install-by-date"; 28 additional days
after installation on system
Room Temperature for up to 1 day |
| Analyzer Type | Handheld | Benchtop |
6
7
PERFORMANCE CHARACTERISTICS VII.
A. Analytical Performance
a. Precision/Reproducibility:
i. Precision 20 days (Aqueous materials)
The precision of the i-STAT pH, Partial Pressure of Oxygen (PO2), and Partial Pressure of Carbon Dioxide (PCO2) tests in the i-STAT CG8+ cartridge on the i-STAT 1 System was evaluated using five (5) levels of aqueous material. This 20day 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 analyzers and one (1) test cartridge lot over 20 days at one site. Repeatability, between-run, between-day, and within-laboratory precision were estimated for each level. The results of the 20-day precision study for the i-STAT CG8+ cartridge on the i-STAT 1 System are shown in Table 2.
| Table 2: Results of 20-Day Precision of the i-STAT CG8+ Cartridge on the i-STAT 1 Analyzer | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Test | Fluid | |||||||||||
| Level | N | Mean | Repeatability | Between-run | Between-day | Within- | ||||||
| Laboratory | ||||||||||||
| (units) | SD | %CV | SD | %CV | SD | %CV | SD | %CV | ||||
| pH | ||||||||||||
| (pH units) | CV L1 | 80 | 6.5831 | 0.00284 | 0.04 | 0.00354 | 0.05 | 0.00162 | 0.02 | 0.00482 | 0.07 | |
| CV L2 | 80 | 7.0326 | 0.00165 | 0.02 | 0.00121 | 0.02 | 0.00102 | 0.01 | 0.00229 | 0.03 | ||
| CV L3 | 80 | 7.4574 | 0.00118 | 0.02 | 0.00170 | 0.02 | 0.00065 | 0.01 | 0.00217 | 0.03 | ||
| CV L4 | 80 | 7.6365 | 0.00133 | 0.02 | 0.00201 | 0.03 | 0.00072 | 0.01 | 0.00251 | 0.03 | ||
| CV L5 | 80 | 7.9612 | 0.00244 | 0.03 | 0.00188 | 0.02 | 0.00090 | 0.01 | 0.00321 | 0.04 | ||
| PO2 | ||||||||||||
| (mmHg) | CV L1 | 80 | 75.7 | 1.93 | 2.54 | 1.45 | 1.92 | 0.77 | 1.02 | 2.53 | 3.35 | |
| CV L2 | 80 | 87.3 | 1.81 | 2.07 | 0.46 | 0.53 | 0.55 | 0.63 | 1.94 | 2.23 | ||
| CV L3 | 80 | 115.0 | 2.40 | 2.08 | 1.76 | 1.53 | 0.47 | 0.41 | 3.01 | 2.62 | ||
| CV L4 | 80 | 144.1 | 2.74 | 1.90 | 2.62 | 1.82 | 1.02 | 0.70 | 3.92 | 2.72 | ||
| CV L5 | 80 | 371.6 | 6.25 | 1.68 | 8.29 | 2.23 | 2.97 | 0.80 | 10.80 | 2.91 |
8
| Table 2: Results of 20-Day Precision of the i-STAT CG8+ Cartridge on the i-STAT 1 Analyzer | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Test | ||||||||||||
| (units) | Fluid | |||||||||||
| Level | N | Mean | Repeatability | Between-run | Between-day | Within- | ||||||
| Laboratory | ||||||||||||
| SD | %CV | SD | %CV | SD | %CV | SD | %CV | |||||
| PCO2 | ||||||||||||
| (mmHg) | CV L1 | 80 | 88.55 | 0.781 | 0.88 | 0.973 | 1.10 | 0.392 | 0.44 | 1.307 | 1.48 | |
| CV L2 | 80 | 54.96 | 0.598 | 1.09 | 0.139 | 0.25 | 0.055 | 0.10 | 0.616 | 1.12 | ||
| CV L3 | 80 | 28.90 | 0.300 | 1.04 | 0.082 | 0.28 | 0.082 | 0.28 | 0.321 | 1.11 | ||
| CV L4 | 80 | 22.59 | 0.268 | 1.19 | 0.112 | 0.50 | 0.066 | 0.29 | 0.298 | 1.32 | ||
| CV L5 | 80 | 13.81 | 0.335 | 2.42 | 0.157 | 1.13 | 0.181 | 1.31 | 0.412 | 2.98 |
ii. Multi-site and operator-to-operator precision (Aqueous materials)
Multi-day precision testing was performed at three (3) sites using a panel of aqueous solutions containing five (5) levels of pH, PO2, and PCO2. At each site, each level was tested once a day by two (2) operators for five (5) days on six (6) i-STAT 1 analyzers using i-STAT CG8+ cartridges. Within-run, between-day, betweenoperator and within-site (total) variance components were calculated by site. These components were also calculated for all sites combined and provided in the Table 3 below.
9
| Table 3: Multi-Day Precision of the i-STAT CG8+ Cartridge on the i-STAT 1 Analyzer | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Test | |||||||||||||||
| (units) | Fluid | ||||||||||||||
| Level | N | Mean | Within-Run | Between-Day | Between-Operator | Within-Site (Total) | Between-Site | Overall | |||||||
| SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | ||||
| pH | |||||||||||||||
| (pH units) | CV L1 | 90 | 6.5829 | 0.00395 | 0.06 | 0.00267 | 0.04 | 0.00329 | 0.05 | 0.00579 | 0.09 | 0.00000 | 0.00 | 0.00579 | 0.09 |
| CV L2 | 90 | 7.0332 | 0.00317 | 0.05 | 0.00135 | 0.02 | 0.00054 | 0.01 | 0.00349 | 0.05 | 0.00000 | 0.00 | 0.00349 | 0.05 | |
| CV L3 | 96 | 7.4571 | 0.00231 | 0.03 | 0.00080 | 0.01 | 0.00085 | 0.01 | 0.00258 | 0.03 | 0.00000 | 0.00 | 0.00258 | 0.03 | |
| CV L4 | 90 | 7.6372 | 0.00184 | 0.02 | 0.00038 | 0.01 | 0.00116 | 0.02 | 0.00221 | 0.03 | 0.00000 | 0.00 | 0.00221 | 0.03 | |
| CV L5 | 90 | 7.9627 | 0.00256 | 0.03 | 0.00035 | 0.00 | 0.00110 | 0.01 | 0.00281 | 0.04 | 0.00000 | 0.00 | 0.00281 | 0.04 | |
| PO2 | |||||||||||||||
| (mmHg) | CV L1 | 91 | 81.1 | 2.73 | 3.37 | 1.00 | 1.23 | 1.56 | 1.92 | 3.30 | 4.07 | 0.00 | 0.00 | 3.30 | 4.07 |
| CV L2 | 90 | 91.2 | 3.34 | 3.67 | 1.31 | 1.43 | 0.84 | 0.92 | 3.69 | 4.04 | 0.00 | 0.00 | 3.69 | 4.04 | |
| CV L3 | 97 | 118.3 | 2.38 | 2.01 | 1.06 | 0.89 | 0.93 | 0.78 | 2.76 | 2.34 | 0.99 | 0.84 | 2.94 | 2.48 | |
| CV L4 | 90 | 147.3 | 2.39 | 1.62 | 2.17 | 1.48 | 2.29 | 1.56 | 3.96 | 2.69 | 0.00 | 0.00 | 3.96 | 2.69 | |
| CV L5 | 90 | 367.7 | 6.27 | 1.71 | 4.25 | 1.16 | 9.62 | 2.62 | 12.24 | 3.33 | 0.00 | 0.00 | 12.24 | 3.33 | |
| PCO2 | |||||||||||||||
| (mmHg) | CV L1 | 90 | 88.67 | 1.308 | 1.48 | 0.349 | 0.39 | 0.620 | 0.70 | 1.489 | 1.68 | 0.000 | 0.00 | 1.489 | 1.68 |
| CV L2 | 90 | 56.08 | 0.652 | 1.16 | 0.379 | 0.68 | 0.000 | 0.00 | 0.754 | 1.35 | 0.000 | 0.00 | 0.754 | 1.35 | |
| CV L3 | 96 | 29.42 | 0.332 | 1.13 | 0.173 | 0.59 | 0.033 | 0.11 | 0.376 | 1.28 | 0.000 | 0.00 | 0.376 | 1.28 | |
| CV L4 | 90 | 22.73 | 0.379 | 1.67 | 0.166 | 0.73 | 0.105 | 0.46 | 0.427 | 1.88 | 0.000 | 0.00 | 0.427 | 1.88 | |
| CV L5 | 90 | 13.17 | 0.381 | 2.89 | 0.188 | 1.43 | 0.123 | 0.93 | 0.442 | 3.36 | 0.181 | 1.37 | 0.477 | 3.63 |
10
iii. Precision (Whole Blood)
Whole blood precision of the i-STAT pH, PO2, and PCO2 tests in the i-STAT CG8+ cartridge on the i-STAT 1 System was evaluated using arterial, venous, and capillary1 whole blood specimens collected with lithium heparin. The whole blood precision was assessed using the duplicate test results collected across multiple point of care sites. The results are summarized in Table 4.
| Test
| (units) | Sample Type | Sample Range | N | Mean | SD | %CV |
|---|---|---|---|---|---|---|
| pH | ||||||
| (pH units) | Venous Whole | |||||
| Blood | 6.500-7.300 | 14 | 7.0076 | 0.00378 | 0.05 | |
| Venous Whole | ||||||
| Blood | >7.300-7.450 | 95 | 7.3790 | 0.00605 | 0.08 | |
| Venous Whole | ||||||
| Blood | >7.450-7.800 | 9 | 7.5257 | 0.00350 | 0.05 | |
| pH | ||||||
| (pH units) | Arterial Whole | |||||
| Blood | 6.500-7.300 | 7 | 7.2059 | 0.00292 | 0.04 | |
| Arterial Whole | ||||||
| Blood | >7.300-7.450 | 100 | 7.3772 | 0.00574 | 0.08 | |
| Arterial Whole | ||||||
| Blood | >7.450-7.800 | 41 | 7.4704 | 0.00585 | 0.08 | |
| pH | ||||||
| (pH units) | Capillary Whole | |||||
| Blood | 6.500-7.300 | 0 | N/A | N/A | N/A | |
| Capillary Whole | ||||||
| Blood | >7.300-7.450 | 108 | 7.4075 | 0.01847 | 0.25 | |
| Capillary Whole | ||||||
| Blood | >7.450-7.800 | 45 | 7.4729 | 0.02508 | 0.34 | |
| PO2 | ||||||
| (mmHg) | Venous Whole | |||||
| Blood | 10-40 | 72 | 30.5 | 0.98 | 3.21 | |
| Venous Whole | ||||||
| Blood | >40-50 | 15 | 44.7 | 0.68 | 1.53 | |
| Venous Whole | ||||||
| Blood | >50-100 | 20 | 58.9 | 1.17 | 1.99 | |
| Venous Whole | ||||||
| Blood | >100-250 | 5 | 141.1 | 4.72 | 3.35 | |
| Venous Whole | ||||||
| Blood | >250-700 | 6 | 550.1 | 5.35 | 0.97 | |
| PO2 | ||||||
| (mmHg) | Arterial Whole | |||||
| Blood | 10-40 | 2 | 37.3 | 1.12 | 3.00 | |
| Arterial Whole | ||||||
| Blood | >40-50 | 3 | 48.2 | 1.22 | 2.54 | |
| Arterial Whole | ||||||
| Blood | >50-100 | 61 | 76.7 | 1.26 | 1.64 | |
| Arterial Whole | ||||||
| Blood | >100-250 | 66 | 161.2 | 3.87 | 2.40 | |
| Arterial Whole | ||||||
| Blood | >250-700 | 15 | 323.3 | 7.45 | 2.30 | |
| PO2 | ||||||
| (mmHg) | Capillary Whole | |||||
| Blood | 10-40 | 5 | 36.3 | 1.52 | 4.18 | |
| Capillary Whole | ||||||
| Blood | >40-50 | 13 | 45.5 | 2.49 | 5.47 | |
| Capillary Whole | ||||||
| Blood | >50-100 | 136 | 70.4 | 7.50 | 10.65 | |
| Capillary Whole | ||||||
| Blood | >100-250 | 0 | N/A | N/A | N/A | |
| Capillary Whole | ||||||
| Blood | >250-700 | 0 | N/A | N/A | N/A | |
| PCO2 | ||||||
| (mmHg) | Venous Whole | |||||
| Blood | 5.0-35.0 | 27 | 33.30 | 0.555 | 1.67 | |
| Venous Whole | ||||||
| Blood | >35.0-50.0 | 70 | 45.32 | 0.777 | 1.71 | |
| Venous Whole | ||||||
| Blood | >50.0-62.5 | 14 | 55.79 | 1.592 | 2.85 | |
| Venous Whole | ||||||
| Blood | >62.5-130.0 | 9 | 97.07 | 1.312 | 1.35 | |
| PCO2 | ||||||
| (mmHg) | Arterial Whole | |||||
| Blood | 5.0-35.0 | 51 | 33.76 | 0.714 | 2.12 | |
| Arterial Whole | ||||||
| Blood | >35.0-50.0 | 85 | 43.56 | 0.958 | 2.20 | |
| Arterial Whole | ||||||
| Blood | >50.0-62.5 | 10 | 60.78 | 0.489 | 0.81 | |
| Arterial Whole | ||||||
| Blood | >62.5-130.0 | 2 | 87.85 | 0.570 | 0.65 | |
| PCO2 | ||||||
| (mmHg) | Capillary Whole | |||||
| Blood | 5.0-35.0 | 51 | 31.23 | 2.048 | 6.56 | |
| Capillary Whole | ||||||
| Blood | >35.0-50.00 | 97 | 40.16 | 1.749 | 4.36 | |
| Capillary Whole | ||||||
| Blood | >50.0-62.5 | 5 | 54.82 | 2.835 | 5.17 | |
| Capillary Whole | ||||||
| Blood | >62.5-130 | 0 | N/A | N/A | N/A |
1 The capillary whole blood clinical precision study design involved the performance of two individual fingersticks, collected independently by two operators into two separate capillary tubes and tested on two (2) i-STAT CG8+ cartridges.
11
b. Linearity/assay reportable range:
Linearity i.
The study was designed based on CLSI EP06-Ed2: Evaluation of the Linearity of Quantitative Measurement Procedures - Second Edition.
The linearity of the i-STAT pH, PO2, and PCO2 tests in the i-STAT CG8+ cartridge with the i-STAT 1 System was evaluated by preparing whole blood samples of varying analyte levels for each i-STAT test. The i-STAT pH, PO2, and PCO2 tests in the i-STAT CG8+ cartridge demonstrated linearity over the reportable range for each i-STAT test. Regression summary of the response for each i-STAT test versus the concentration of the whole blood samples of varying analyte levels is provided in Table 5 for i-STAT CG8+ cartridge.
| Table 5: Regression Summary for the i-STAT pH, PO2 and PCO2 tests in the i-STAT CG8+ | ||||||
|---|---|---|---|---|---|---|
| Cartridge on the i-STAT 1 Analyzer | ||||||
| Test | Units | Reportable Range | Range Tested | Slope | Intercept | R2 |
| pH | pH units | 6.500 – 7.800 | 6.4290 – 7.8522 | 1.011 | -0.098 | 0.9994 |
| PO2 | mmHg | 5 – 700 | 4.4 – 700.0 | 0.977 | 1.062 | 0.9956 |
| PCO2 | mmHg | 5.0 – 130.0 | 2.40 – 148.38 | 1.029 | -1.144 | 0.9991 |
c. Detection Limit
i. 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 pH, PO2 and PCO2 tests in the i-STAT CG8+ cartridge was evaluated on the i-STAT 1 analyzer using two (2) i-STAT CG8+ cartridge lots and whole blood that was altered to a low analyte level for each i-STAT test. The LoQ for the i-STAT pH, PO2, and PCO2 tests in the i-STAT CG8+ cartridge and i-STAT EG7+ cartridge was determined to be at or below the lower limit of the reportable range for each of the i-STAT tests as shown in Table 6.
| Table 6: Summary of LoQ Results for i-STAT Tests in the i-STAT CG8+ Cartridge | ||
|---|---|---|
| Test (units) | Lower limit of the reportable range | Determined LoQ i-STAT CG8+ Cartridge |
| pH (pH Units) | 6.500 | 6.464 |
| PO2 (mmHg) | 5 | 5 |
| PCO2 (mmHg) | 5.0 | 3.2 |
d. Analytical Specificity
i. Interference
The study was based on CLSI EP07-ED3: Interference Testing in Clinical Chemistry, Third Edition.
The interference performance of the i-STAT pH, PO2, and PCO2 tests in the i-STAT CG8+ cartridge on the i-STAT 1 analyzer with the i-STAT 1 System was evaluated using whole blood samples based on CLSI EP07-ED3: Interference Testing in Clinical Chemistry, Third Edition. The effect of each substance was evaluated by comparing the performance of a control sample, spiked with blank solvent
12
solution, with the test results from a test sample spiked with the potentially interfering substance at the toxic/pathological concentration based on CLSI EP37-ED1: Supplemental Tables for Interference Testing in Clinical Chemistry, First Edition, as applicable. A substance was identified as an interferent if the difference between the control and test samples was outside of the allowable error (±Ea) for the i-STAT test. For an identified interferent, a dose-response was performed to determine the degree of interference as a function of the substance concentration.
Table 7 contains the lists of potentially interfering substances tested and the interference results for the i-STAT CG8+ cartridge.
| Table 7: Potentially Interfering Substances and Test Concentrations for the i-STAT pH, PO2, and
| PCO2 tests in the i-STAT CG8+ Cartridge | |||||
|---|---|---|---|---|---|
| Substance 2 | Test Concentration | i-STAT | |||
| Test | Interference | ||||
| (Yes/No) | Comments | ||||
| mmol/L | |||||
| (unless | |||||
| specified) | mg/dL | ||||
| (unless | |||||
| specified) | |||||
| Acetaminophen | 1.03 | 15.6 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Atracurium | |||||
| (Atracurium Besylate) | 0.0287 | 3.57 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Bilirubin | 0.684 | 40 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Calcium | |||||
| (Calcium Chloride) | 5.0 | 20 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Ethanol | 130 | 600 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Hemoglobin | 10 g/L | 1000 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Ibuprofen | 1.06 | 21.9 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Intralipid 20% | N/A | 2684 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Morphine (Morphine | |||||
| Sodium Salt) | 0.0273 | 0.78 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Potassium | |||||
| (Potassium Chloride) | 8 | 59.6 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Sodium | |||||
| (Sodium Chloride) | 170 | 993.48 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Thiopental | 1.66 | 40.2 | pH | No | |
| PO2 | No | ||||
| PCO2 | No | ||||
| Table 7: Potentially Interfering Substances and Test Concentrations for the i-STAT pH, PO2, and | |||||
| PCO2 tests in the i-STAT CG8+ Cartridge | |||||
| Test Concentration | |||||
| Substance 2 | mmol/L | ||||
| (unless | |||||
| specified) | mg/dL | ||||
| (unless | |||||
| specified) | i-STAT | ||||
| Test | Interference | ||||
| (Yes/No) | Comments | ||||
| Triglyceride | 16.94 | 1500 | pH | No | |
| PO2 | No | ||||
| PCO2 | No |
2 The compound tested to evaluate the interfering substance is presented in parenthesis.
13
ii. Other sensitivity studies
1) Altitude
The performance of the i-STAT pH, PO2 and PCO2 tests in the i-STAT CG8+ cartridge on the i-STAT 1 analyzer at an altitude of approximately 10,000 feet above sea level was evaluated using whole blood samples at relevant analyte levels across the reportable range for each test. The pH, PO2, and PCO2 results obtained from the i-STAT CG8+ cartridge on the i-STAT 1 analyzer were compared to the pH, PO2, and PCO2 results obtained from the i-STAT CG4+ (blue) cartridges on the i-STAT 1 analyzer (comparator device). Passing-Bablok regression analyses between the first replicate of the candidate device (y-axis) and mean of the comparator device (x-axis) were performed based on the CLSI EP09c: Measurement Procedure Comparison and Bias Estimation using Patient Samples, 3rd ed. The results of the correlation coefficient and slope met acceptance criteria and demonstrated equivalent performance between the candidate and comparator conditions at approximately 10,000 feet above sea level. The results are summarized in Table 8.
| Table 8: Summary of Altitude Study Results for the i-STAT CG8+ Cartridge | ||||
|---|---|---|---|---|
| Test | Correlation Coefficient (r) | Slope | ||
| r | 95% CI | Slope | 95% CI | |
| pH | 1.00 | 0.999 to 0.999 | 0.99 | 0.984 to 0.998 |
| PO2 | 1.00 | 0.994 to 0.998 | 1.02 | 1.000 to 1.037 |
| PCO2 | 1.00 | 0.997 to 0.999 | 0.98 | 0.969 to 0.989 |
B. Comparison Studies
a. Method Comparison with Comparator Device
Method comparison for arterial, venous, and capillary whole blood specimens on the i-STAT CG8+ cartridge with the i-STAT 1 System was demonstrated in studies based on CLSI EP09c-ED3: Measurement Procedure Comparison and Bias Estimation Using Patient Samples - Third Edition.
Lithium heparin venous and arterial whole blood specimens collected across multiple point of care sites were evaluated using i-STAT CG8+ cartridges on the i-STAT 1 analyzer against whole blood specimens tested on a comparative method. For pH, PO2, and PCO2, a Passing-Bablok linear regression analysis was performed using the first replicate result from the i-STAT 1 analyzer versus the singlicate result from the comparative method.
Two (2) capillary whole blood specimens collected from skin puncture with balanced heparin capillary tubes from each study subject across multiple point of care sites were evaluated and analyzed in singlicate on the i-STAT 1 analyzer against the comparative method. A Passing-Bablok linear regression analysis for pH, PO2, and PCO2 was
14
performed using the singlicate result from the i-STAT 1 analyzer versus the singlicate result of the comparative method.
The venous, arterial, and capillary whole blood data were pooled, and a Passing-Bablok linear regression analysis was performed using the results from the i-STAT CG8+ cartridges on the i-STAT 1 analyzer versus the comparative method results.
Method comparison results for arterial, venous, and capillary whole blood specimens are shown in Table 9. In the table, N is the number of specimens in the data set, and r is the correlation coefficient.
| Table 9: Method Comparison Results for i-STAT CG8+ Cartridge with i-STAT 1 System | |||||||
|---|---|---|---|---|---|---|---|
| Test | |||||||
| (units) | Comparative Method | ||||||
| Arterial/Venous/Capillary | N | Slope | Intercept | r | Medical | ||
| Decision | |||||||
| Level | Bias at | ||||||
| Medical | |||||||
| Decision | |||||||
| Level | |||||||
| pH | |||||||
| (pH | |||||||
| units) | RAPIDPoint 500/500e | 468 | 1.00 | 0.00 | 0.99 | 7.300 | -0.0040 |
| 7.350 | -0.0040 | ||||||
| 7.400 | -0.0040 | ||||||
| PO2 | |||||||
| (mmHg) | RAPIDPoint 500/500e | 461 | 1.03 | -0.72 | 0.99 | 30 | 0.1 |
| 45 | 0.5 | ||||||
| 60 | 0.9 | ||||||
| PCO2 | |||||||
| (mmHg) | RAPIDPoint 500/500e | 465 | 1.08 | -1.13 | 0.97 | 35.0 | 1.79 |
| 45.0 | 2.63 | ||||||
| 50.0 | 3.04 | ||||||
| 70.0 | 4.71 |
The method comparison results for capillary whole blood specimens only are shown in Table 10.
| Table 10: Results for i-STAT CG8+ Cartridge with i-STAT 1 System – Native and Contrived
| Capillary Specimens | |||||||
|---|---|---|---|---|---|---|---|
| Test | |||||||
| (units) | N | Slope | Intercept | r | Range | ||
| pH | |||||||
| (pH units) | 195 | 1.02 | -0.11 | 0.98 | 6.619 - 7.772 | ||
| PO2 | |||||||
| (mmHg) | 190 | 1.02 | -1.75 | 0.99 | 12.8 - 652.6 | ||
| PCO2 | |||||||
| (mmHg) | 189 | 1.09 | -1.90 | 0.97 | 9.1 - 124.9 |
Bias at the medical decision levels for native capillary whole blood specimens only are shown in Table 11.
| Table 11: Results for i-STAT CG8+ Cartridge with i-STAT 1 System – Native Capillary
| Specimens Bias at Medical Decision Levels | ||||||
|---|---|---|---|---|---|---|
| Test | ||||||
| (units) | N | Range | ||||
| Min | Range | |||||
| Max | Medical | |||||
| Decision Level | Bias | |||||
| Estimate | 95% CI | |||||
| pH | ||||||
| (pH units) | 179 | 7.289 | 7.531 | 7.300 | -0.0160 | (-0.0352, 0.0020) |
| 7.350 | -0.0101 | (-0.0211, 0.0010) | ||||
| 7.400 | -0.0041 | (-0.0083, 0.0008) | ||||
| PO2 | ||||||
| (mmHg) | 175 | 32 | 108 | 30 | -1.8 | (-4.7, 0.9) |
| 45 | -1.3 | (-3.0, 0.2) | ||||
| 60 | -0.7 | (-1.9, 0.1) |
15
| Table 11: Results for i-STAT CG8+ Cartridge with i-STAT 1 System – Native Capillary
| Specimens Bias at Medical Decision Levels | ||||||
|---|---|---|---|---|---|---|
| Test | ||||||
| (units) | N | Range Min | Range Max | Medical Decision Level | Bias | |
| Estimate | 95% CI | |||||
| PCO2 | ||||||
| (mmHg) | 179 | 26.9 | 59.3 | 35.0 | 1.17 | (0.66, 1.75) |
| 45.0 | 1.79 | (0.68, 3.05) | ||||
| 50.0 | 2.11 | (0.48, 3.86) | ||||
| 70.0 | 3.36 | (-0.26, 7.08) |
b. Matrix Equivalence
A matrix equivalence study was conducted to evaluate the performance of the i-STAT pH, PO2 and PCO2 tests in the i-STAT CG8+ cartridge on the i-STAT 1 System using non-anticoagulated venous and arterial whole blood specimens. The study design and analysis method were based on recommendations from the Clinical and Laboratory Standards Institute (CLSI) guideline EP35: Assessment of Equivalence or Suitability of Specimen Types for Medical Laboratory Measurement Procedures, 1st ed. The matrix equivalence of each test in the i-STAT CG8+ cartridge was assessed by comparing arterial or venous whole blood specimens collected without anticoagulant (candidate specimen type) to samples collected with balanced heparin or lithium heparin anticoagulant (primary specimen type). Each specimen was tested in duplicate using two (2) i-STAT CG8+ cartridges with two (2) i-STAT 1 analyzers. A Passing-Bablok linear regression analysis was performed using the first replicate result from the candidate (y-axis) versus the mean result from the primary specimen (x-axis). The regression analysis results are summarized in Table 12. In the table, N is the number of specimens in the data set, and r is the correlation coefficient.
| Table 12: Matrix Equivalence Results | ||||||
|---|---|---|---|---|---|---|
| Test (units) | N | Candidate Specimen Range | Primary Specimen Range | R | Slope | Intercept |
| pH (pH units) | 241 | 7.126-7.585 | 7.130-7.607 | 0.98 | 0.97 | 0.19 |
| PO2 (mmHg) | 241 | 13-606 | 14-555 | 0.98 | 0.94 | 1.28 |
| PCO2 (mmHg) | 241 | 22.0-87.7 | 22.4-85.2 | 0.96 | 1.02 | -0.23 |
CONCLUSION VIII.
The results of these studies demonstrate that performance of the i-STAT pH, PO2, and PCO2 tests in the i-STAT CG8+ cartridge with the i-STAT 1 System are substantially equivalent to the predicate device.