K Number
K240998
Date Cleared
2024-12-13

(246 days)

Product Code
Regulation Number
862.1120
Reference & Predicate Devices
Predicate For
N/A
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

The ABL90 FLEX PLUS System is an in vitro diagnostic, portable, automated analyzer that quantitatively measures pH, blood gas (p02), Oximetry (s02, ctHb, FCOHb, FCOHb, FMetHb, and FHHb), in heparinized arterial and venous whole blood.

The ABL90 FLEX PLUS System is intended for use by trained technologists, nurses, physicians and therapists. It is intended for use in a laboratory environment, near patient, or point-of-care setting. These tests are only performed under a physician's order.

pH and pO2: pH and pO2 measurements are used in the diagnosis and treatment of life-threatening acid-base disturbances.

sO2: Oxygen saturation, more specifically the ratio between the concentration of oxyhemoglobin plus reduced hemoglobin.

ctHb (Total Hemoglobin): Total hemoglobin measure the hemoglobin content of whole blood for the detection of anemia.

FO2Hb: Oxyhemoglobin as a fraction of total hemoglobin.

FCOHb: Carboxyhemoglobin measurements are used to determine the carboxyhemoglobin content of human blood as an aid in the diagnosis of carbon monoxide poisoning.

FMetHb: Methemoglobin as a fraction of total hemoglobin.

FHHb: Reduced hemoglobin as a fraction of total hemoglobin.

Device Description

The ABL90 FLEX PLUS System consists of the ABL90 FLEX PLUS analyzer, sensor cassette and solution pack consumables, and related accessories for the analyzers. The sensor cassettes, solution packs and related accessories are compatible with both analyzers. Multiple versions of the sensor cassettes are available. The sensor cassette versions vary in the maximum number of tests and availability of sensors for use. The solution pack is available in two versions, differing in the number of activities available.

AI/ML Overview

The FDA 510(k) summary for the Radiometer ABL90 FLEX PLUS System provides detailed information about the device's analytical performance testing to demonstrate its substantial equivalence to its predicate device.

Here's a breakdown of the acceptance criteria and the study that proves the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implicitly defined by the reported performance metrics (linearity, detection limits, precision, bias) and the comparison to the predicate device. The goal is to show that the ABL90 FLEX PLUS System performs comparably to the predicate (ABL90 FLEX PLUS, K160153) and adheres to recognized standards (CLSI guidelines).

The summary does not explicitly present a table of "acceptance criteria" and "reported performance" side-by-side in a single formatted table. However, the various tables throughout the "Analytical Performance Testing Summary" section serve this purpose by presenting the measured performance of the ABL90 FLEX PLUS System against unstated, but implied, acceptable ranges or a comparison to the predicate.

Here's a synthesized representation of the reported device performance for key analytical parameters, effectively serving as the "reported device performance":

ParameterPerformance AspectReported Value/Range (ABL90 FLEX PLUS System)Implied Acceptance Criteria (via comparison to predicate and CLSI guidelines)
pHLinearity Interval6.605-7.997Consistent with clinical requirements and predicate's performance.
Lower LoQ6.754Detectable and quantifiable at clinically relevant low levels.
Upper LoQ7.843Detectable and quantifiable at clinically relevant high levels.
Precision (Repeatability SD)0.001-0.003 (blood)Low variability, suitable for clinical use.
Bias (Method comparison to predicate)-0.003Minimal bias from predicate, within clinical acceptable limits.
pO2Linearity Interval0.81-75.41 kPa (or mmHg equivalent)Consistent with clinical requirements and predicate's performance.
LoQ7.7 mmHg (1.02 kPa)Detectable and quantifiable at clinically relevant low levels.
Precision (Repeatability SD)0.197-1.91 (blood/QC)Low variability, suitable for clinical use.
Bias (Method comparison to predicate)-0.454 to 0.344Minimal bias from predicate, within clinical acceptable limits.
ctHbLinearity Interval0.068-27.660 g/dLConsistent with clinical requirements and predicate's performance.
LoQ0.09 g/dLDetectable and quantifiable at clinically relevant low levels.
Precision (Repeatability SD)0.01-0.091 (blood/QC)Low variability, suitable for clinical use.
Bias (Method comparison to predicate)0.015-0.126Minimal bias from predicate, within clinical acceptable limits.
Oximetry (sO2, FO2Hb, FCOHb, FMetHb, FHHb)Linearity IntervalRanges provided for each (e.g., sO2: 2.18-100.22%)Consistent with clinical requirements and predicate's performance.
LoQRanges provided for each (e.g., sO2: 1.4%)Detectable and quantifiable at clinically relevant low levels.
Precision (Repeatability SD)Low variability reported across all oximetry parameters (blood/QC)Low variability, suitable for clinical use.
Bias (Method comparison to predicate)Minimal bias reported across all oximetry parametersMinimal bias from predicate, within clinical acceptable limits.
InterferenceVarious interferents (Intralipid, Bilirubin, etc.)Reported impact on results, indicating levels where interference was not significant or error messages occurred.Acceptable performance with common interferents, or clear warnings for known interferences.

Key takeaway for "Acceptance Criteria": The general acceptance criterion for this 510(k) submission is to demonstrate "substantial equivalence" to the predicate device (ABL90 FLEX PLUS, K160153). While explicit numerical acceptance criteria are not presented in this summary document, the testing aims to show that the new device's performance (linearity, detection, precision, bias, interference) is comparable to the predicate and/or meets recognized clinical and analytical standards as outlined in CLSI guidelines.

2. Sample Sizes Used for the Test Set and Data Provenance

  • Linearity Testing: Numbers of samples are not explicitly stated for linearity testing, but it was conducted "in general accordance with CLSI EP06... and EP39."
  • Detection Capability (LoB, LoD, LoQ): Numbers of samples are not explicitly stated.
  • Precision (using stable, aqueous ampoule-based QC material):
    • N = 243 or 244 for each QC ampoule level and parameter.
    • Data Provenance: Testing occurred at three external sites. The specific countries of origin are not mentioned, but "external sites" suggests a multi-site study. This appears to be a prospective study, as it's part of the premarket submission.
  • Precision (using blood):
    • N varies by parameter and test interval, ranging from 4 to 188 samples.
    • Data Provenance: Not explicitly stated, but implies collected from blood samples (human derived). Likely prospective data collected for the study.
  • Method Comparison (Bias):
    • N varies by parameter, blood type, and mode (S65/SP65), ranging from 26 to 235 samples (arterial/venous blood).
    • Data Provenance: Not explicitly stated, but implies collected from patient blood samples. This would be prospective data collected specifically for the method comparison study.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of those Experts

This device (ABL90 FLEX PLUS System) is an in vitro diagnostic (IVD) analytical instrument. The ground truth for its performance is established through reference methods, defined concentrations of analytes in quality control materials, and comparison to a legally marketed predicate device, not typically through human expert adjudication of images or clinical outcomes that require multiple medical professionals.

Therefore, the concept of "experts establishing ground truth" in the way it might apply to an AI imaging device (e.g., radiologists reviewing scans) is not directly applicable here. The "experts" would be the laboratory personnel and analytical chemists who perform the testing and ensure adherence to CLSI guidelines. Their qualifications are implicitly assumed to be appropriate for performing such technical laboratory studies.

4. Adjudication Method for the Test Set

Not applicable for an IVD analytical instrument. Ground truth is established by reference methods, certified materials, and comparison with a predicate device, not by expert adjudication.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done

Not applicable. MRMC studies are typically performed for imaging devices or diagnostic aids where human interpretation is a key component, often comparing AI-assisted vs. unassisted human performance. This device is an automated, quantitative analytical instrument.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done

Yes, the performance data presented (linearity, detection/quantitation, precision, bias, interference) are all measures of the standalone analytical performance of the ABL90 FLEX PLUS System. The device provides quantitative measurements autonomously without continuous human interpretation required for each result.

7. The Type of Ground Truth Used

The ground truth used for this device's analytical performance studies are:

  • Reference materials/Certified Analytes: For linearity, detection, and precision testing. These are materials with known, precisely measured concentrations of the analytes (pH, pO2, ctHb, sO2, etc.).
  • Predicate Device Measurements: For method comparison/bias studies, the measurements from the legally marketed ABL90 FLEX PLUS (K160153) served as the comparator (or "ground truth" to determine bias relative to the predicate).
  • CLSI Guidelines: The studies adhere to relevant Clinical and Laboratory Standards Institute (CLSI) guidelines (e.g., EP06, EP39, EP17-A2, EP05-A3, EP09c, EP07, EP37), which define accepted methodologies and performance characteristics for IVD devices.

8. The Sample Size for the Training Set

Not applicable. This document describes the performance testing for a finished IVD product, not the development or training of a machine learning model. IVD devices like the ABL90 FLEX PLUS System are based on established analytical principles (potentiometry, optical, spectrophotometry) and calibrated using defined reference materials, not "trained" on a dataset in the AI sense.

9. How the Ground Truth for the Training Set Was Established

Not applicable, as there is no "training set" in the context of this device's analytical principles. Ground truth for calibration and development of such instruments is established through rigorous analytical chemistry methods using highly purified and characterized reference standards.

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December 13, 2024

Image /page/0/Picture/1 description: The image shows the logo for the U.S. Food and Drug Administration (FDA). The logo consists of two parts: the Department of Health and Human Services seal on the left and the FDA acronym with the full name of the agency on the right. The FDA part of the logo is in blue, with the acronym in a square and the full name written out to the right of the square. The full name reads "U.S. Food & Drug Administration" with the word "Administration" on the second line.

Radiometer Medicals ApS Andrea Swingle Senior Specialist, Regulatory Affairs Aakandevej 21 2700 Broenshoej Denmark

Re: K240998

Trade/Device Name: ABL90 FLEX PLUS 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, GKR, GHS Dated: November 15, 2024 Received: November 15, 2024

Dear Andrea Swingle:

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.

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).

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

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approvals in the device master record (21 CFR 820.181).

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

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.

All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-device-advicecomprehensive-regulatory-assistance/unique-device-identification-system-udi-system.

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.

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3

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. Deputy Division 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

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Indications for Use

510(k) Number (if known) K240998

Device Name ABL90 FLEX PLUS System

Indications for Use (Describe)

The ABL90 FLEX PLUS System is an in vitro diagnostic, portable, automated analyzer that quantitatively measures pH, blood gas (p02), Oximetry (s02, ctHb, FCOHb, FCOHb, FMetHb, and FHHb), in heparinized arterial and venous whole blood.

The ABL90 FLEX PLUS System is intended for use by trained technologists, nurses, physicians and therapists. It is intended for use in a laboratory environment, near patient, or point-of-care setting. These tests are only performed under a physician's order.

pH and pO2: pH and pO2 measurements are used in the diagnosis and treatment of life-threatening acid-base disturbances.

sO2: Oxygen saturation, more specifically the ratio between the concentration of oxyhemoglobin plus reduced hemoglobin.

ctHb (Total Hemoglobin): Total hemoglobin measure the hemoglobin content of whole blood for the detection of anemia.

FO2Hb: Oxyhemoglobin as a fraction of total hemoglobin.

FCOHb: Carboxyhemoglobin measurements are used to determine the carboxyhemoglobin content of human blood as an aid in the diagnosis of carbon monoxide poisoning.

FMetHb: Methemoglobin as a fraction of total hemoglobin.

FHHb: Reduced hemoglobin as a fraction of total hemoglobin.

Type of Use (Select one or both, as applicable)

X Prescription Use (Part 21 CFR 801 Subpart D)

| Over-The-Counter Use (21 CFR 801 Subpart C)

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510(k) Summary - K240998

The information provided in this 510(k) summary are in accordance with 21 CFR 807.92

Submitter Information:

Company Name:Radiometer Medical ApS
ER Number:3002807968
Address:Aakandevej 212700 BroenshoejDenmark
Contact Person:Hsiao-Qing Chow
Phone:+45 31401578

Application Correspondent:

Name:Andrea Swingle
Function:Senior Specialist, Regulatory Affairs
Email:andrea.swingle@radiometeramerica.com
Phone:+1 510 246 2559

Date prepared: December 13, 2024

Device Information

Device Trade Name:ABL90 FLEX PLUS System
Common Name:Blood Gas Analyzer
Regulations:- 21 CFR 862.1120, Blood gases (pCO2, pO2) and blood pH test system- 21 CFR 864.5620, Automated hemoglobin system- 21 CFR 864.7425, Carboxyhemoglobin assay
Product Codes:CHL, GKR, GHS
Device Class:Class II
Predicate Device
Device Trade Name:ABL90 FLEX PLUS
Common Name:Blood Gas Analyzer
510(k)K160153
Regulations:- 21 CFR 862.1120, Blood gases (pCO2, pO2) and blood pH test system- 21 CFR 864.5620, Automated hemoglobin system- 21 CFR 864.7425, Carboxyhemoglobin assay
Product Codes:CHL, GKR, GHS
Device Class:Class II

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Device Description

The ABL90 FLEX PLUS System consists of the ABL90 FLEX PLUS analyzer, sensor cassette and solution pack consumables, and related accessories for the analyzers. The sensor cassettes, solution packs and related accessories are compatible with both analyzers. Multiple versions of the sensor cassettes are available. The sensor cassette versions vary in the maximum number of tests and availability of sensors for use. The solution pack is available in two versions, differing in the number of activities available.

Intended Use

The ABL90 FLEX PLUS System is an in vitro diagnostic, portable, automated analyzer that quantitatively measures pH, blood gas (p02), Oximetry (s02, ctHb, FCOHb, FMetHb, and FHHb), in heparinized arterial and venous whole blood.

The ABL90 FLEX PLUS System is intended for use by trained technologists, nurses, physicians and therapists. It is intended for use in a laboratory environment, near patient, or point-of-care setting.

These tests are only performed under a physician's order.

pH and pO2: pH and pO2 measurements are used in the diagnosis and treatment of lifethreatening acid-base disturbances.

s02: Oxygen saturation, more specifically the ratio between the concentration of oxyhemoglobin and oxyhemoglobin plus reduced hemoglobin.

ctHb (Total Hemoglobin): Total hemoglobin measurements are used to measure the hemoglobin content of whole blood for the detection of anemia.

FO2Hb: Oxyhemoqlobin as a fraction of total hemoglobin.

FCOHb: Carboxyhemoqlobin measurements are used to determine the carboxyhemoglobin content of human blood as an aid in the diagnosis of carbon monoxide poisoning.

FMetHb: Methemoqlobin as a fraction of total hemoglobin.

FHHb: Reduced hemoglobin as a fraction of total hemoglobin.

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Substantial Equivalence Comparison

Substantial equivalence comparison table

ABL90 FLEX PLUS System(This 510(k))ABL90 FLEX PLUS(510(k) K160153)
ManufacturerRadiometer MedicalRadiometer Medical
Indications for UseThe ABL90 FLEX PLUS System is anIn Vitro diagnostic, portable,automated analyzer thatquantitatively measures, pH, bloodgases ( $pO_2$ ), Oximetry ( $sO_2$ , ctHb,$FO_2Hb$ , FCOHb, FMetHb, and FHHb),in heparinized arterial and venouswhole blood.The ABL90 FLEX analyzer is an InVitro diagnostic, portable, automatedanalyzer that quantitativelymeasures, pH, blood gases,electrolytes, glucose, lactate andoximetry in heparinized whole blood,and neonatal bilirubin in heparinizedcapillary, venous and arterial wholeblood.Bilirubin measurements on the ABL90FLEX PLUS analyzer are intended toaid in assessing the risk ofkernicterus in neonates.
Intended UseMeasurement of pH, $pO_2$ , $sO_2$ , ctHb,$FO_2Hb$ , FCOHb, FMetHb, and FHHbMeasurement of pH, $pO_2$ , $sO_2$ , ctHb,$FO_2Hb$ , FCOHb, FMetHb, and FHHb
Intended useenvironmentLaboratory environment, near patientor point-of-care settingLaboratory environment, near patientor point-of-care setting
Prescription/OTCUsePrescriptionPrescription
Sample requirements
Sample typeHeparinized whole blood (arterial,venous)Heparinized whole blood (arterial,venous, capillary)
Compatiblesampling devicesRadiometer samplers (in S65 mode)and non-Radiometer samplers (in S65mode)Radiometer samplers (in S65 mode)and non-Radiometer samplers (in S65mode)
Sample volume65 μL65 μL
SamplepreparationWith balanced heparin anticoagulantWith balanced heparin anticoagulant
Device design
OperatingprinciplesPotentiometry: pHOptical: $pO_2$Spectrophotometry: $sO_2$ , ctHb,$FO_2Hb$ , FCOHb, FMetHb, and FHHbPotentiometry: pHOptical: $pO_2$Spectrophotometry: $sO_2$ , ctHb,$FO_2Hb$ , FCOHb, FMetHb, and FHHb
MajorcomponentsTouch screen Barcode reader Sample mixer Inlet module Fluid transport system Oximetry module Electronics Software Printer Optional battery pack Communication portsTouch screen Barcode reader Sample mixer Inlet module Fluid transport system Oximetry module Electronics Software Printer Optional battery pack Communication ports
ABL90 FLEX PLUS System(This 510(k))ABL90 FLEX PLUS(510(k) K160153)
ConsumablesSensor cassette Solution packSensor cassette Solution pack
Performance characteristics
ReportablerangespH: 6.818 - 7.797pO2: 30.1 - 488 mmHgsO2: 3.3 - 100.0%ctHb: 0.1 - 24.0 g/dLFO2Hb: 3.3 - 98.5%FCOHb: 1.00 - 92.2%FMetHb: 0.5 - 91%FHHb: 1.5 - 98.3%pH: 6.818 - 7.797pO2: 30.1 - 488 mmHgsO2: 3.3 - 100.0%ctHb: 0.1 - 24.0 g/dLFO2Hb: 3.3 - 98.5%FCOHb: 1.00 - 92.2%FMetHb: 1.0 - 91%FHHb: 2.4 - 98.5%

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Analytical Performance Testing Summary

The ABL90 FLEX PLUS System has been tested for analytical performance, including tests for linearity, limit of blank, detection and quantification, precision, bias, interference, stability. The tests were conducted in general accordance with Clinical Laboratory Standards Institute (CLSI) guidelines, all of which are FDA-recognized consensus standards.

Linearity

Linearity testing was conducted in general accordance with CLSI EP06, Evaluation of the Linearity of Quantitative Measurement Procedures, 2nd Edition and EP39, A Hierarchical Approach to Selecting Surrogate Samples for the Evaluation of In Vitro Medical Laboratory Tests, 1st Edition. The resulting linearity intervals are listed in Table 1.

ParameterLinearity interval
Ph6.605-7.997
pO20.81-75.41 kPa
ctHb0.068-27.660 g/dL
sO22.18-100.22 %
FO2Hb2.18-98.96 %
FCOHb0.54-95.79 %
FMetHb0.49-95.61 %
FHHb0.53-98.37 %

Table 1: I inearity results

Detection

Detection capability testing in terms of limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ) was conducted. in general accordance with CLSI EP17-A2, Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures, and EP39, A Hierarchical Approach to Selecting Surrogate Samples for the Evaluation of In Vitro Medical Laboratory Tests, 1st Edition. Table 2 shows the results of the detection testing.

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ParameterUnitLower LoQUpper LoQ
pH-6.7547.843
ParameterUnitLoBLoDLoQ
$pO_2$mmHgN/AN/A7.7
kPa1.02
ctHbg/dL0.030.090.09
FHHb%0.20.61.4
Fraction0.0020.0060.014
$sO_2$%N/AN/A1.4
Fraction0.014
$FO_2$ Hb%N/AN/A1.4
Fraction0.014
FCOHb%N/AN/A0.7
Fraction0.007
FMetHb%N/AN/A0.3
Fraction0.003

Table 2: Detection results

N/A: Not applicable

Precision

Two precision studies were performed; both were in general accordance with CLSI EP05-A3, Evaluation of Precision of Quantitative Measurement Procedures.

Precision using stable, aqueous ampoule-based QC material

The primary endpoints of the study were repeatability and within laboratory precision for pooled across several sites. The secondary endpoint was reproducibility between sites. The sample material was Radiometer QUALICHECK5+ QC ampoules, a QC material that comes in four "levels". Testing occurred at three external sites. Table 3 presents the data on the primary and secondary endpoints.

ParameterQC ampouleNMeanRepeatabilityWithin Lab PrecisionReproducibility
SDCV%SDCV%SDCV%
FCOHb(%)QC5+ L 12435.90.030.60.061.00.111.8
QC5+ L 22442.80.031.10.082.90.134.7
QC5+ L 324420.00.020.10.050.30.050.3
QC5+ L 424410.10.020.20.030.30.060.6
FMetHb(%)QC5+ L 12435.00.010.30.030.60.050.9
QC5+ L 22442.00.020.80.042.10.052.3
QC5+ L 324410.00.020.20.020.20.030.3
QC5+ L 424420.10.040.20.060.30.090.4

Table 3: Precision results using QC materials

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RADIOME

ParameterQC ampouleNMeanRepeatabilityWithin LabPrecisionReproducibility
SDCV%SDCV%SDCV%
FHHb(%)QC5+ L 124344.60.030.10.050.10.130.3
QC5+ L 22443.00.020.70.062.00.093.2
QC5+ L 324421.00.010.10.030.10.030.1
QC5+ L 424466.30.050.10.070.10.130.2
FO2Hb(%)QC5+ L 124344.60.030.10.050.10.050.1
QC5+ L 224492.20.040.00.060.10.060.1
QC5+ L 324449.00.020.10.050.10.050.1
QC5+ L 42443.50.010.30.030.70.030.8
pHQC5+ L 12437.0660.00340.00.00340.00.00380.1
QC5+ L 22447.3900.00180.00.00180.00.00190.0
QC5+ L 32447.5820.00180.00.00180.00.00180.0
QC5+ L 42446.7840.00370.10.00370.10.00410.1
pO2(mmHg)QC5+ L 1243154.31.911.22.871.93.132.0
QC5+ L 2244100.31.131.12.012.02.012.0
QC5+ L 324456.10.951.71.332.41.332.4
QC5+ L 4244310.03.001.05.511.86.952.2
sO2(%)QC5+ L 124350.00.010.00.020.00.060.1
QC5+ L 224496.90.030.00.070.10.120.1
QC5+ L 324470.00.010.00.030.00.030.0
QC5+ L 42445.00.010.20.030.50.030.5
ctHb(g/dL)QC5+ L 12438.10.020.20.030.40.040.6
QC5+ L 224412.90.030.20.040.30.060.5
QC5+ L 324419.30.030.20.060.30.090.5
QC5+ L 42442.70.010.40.020.60.020.6

N: Number of data points for analysis SD: Standard Deviation CV%: %Coefficient of Variation QC5+ L X: QUALICHECK5+ Level X

Precision using blood

The primary endpoint of the study was repeatability, designated SD, pooled across sites. Two levels of concentration were covered for all parameters. Testing was conducted in both samples collection modes: syringe/S65 mode and short probe/SP65 mode. Table 4 summarize the results of the study.

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Parameter (unit)NTest intervalMeanRepeatabilitySDCV%
S65 Mode
pH (pH unit)186.9 - <7.27.1410.0030.04
387.2 - <7.357.2980.0020.03
1307.35 - <7.457.4050.0030.04
607.45 - <7.557.4800.0030.04
pO2 (mmHg)4830.1 - <6041.9040.2520.60
11460 - <8373.4241.0311.40
4283 - <10890.7711.1981.32
18108 - <150124.500.8500.68
ctHb (g/dL)246.750 - 7.9507.5330.0821.08
1848.050 - 13.25010.7840.0830.77
3413.550 - 17.15014.9410.0770.51
sO2 (%)343.3 - <8064.2210.8901.39
3680 - <9491.7670.1470.16
15894 - <10096.9340.1770.18
FO2Hb (%)343.3 - <8063.2150.9181.45
6480 - <9491.6770.1460.16
13094 - <98.596.0830.1650.17
FMetHb (%)620.5 - <1.50.7970.0708.73
41.5 - <201.8250.0502.74
1220 - <5040.6670.0580.14
FCOHb (%)1621 - <51.3230.0594.48
65 - <3532.7330.0580.18
1235 - <5039.4920.0650.16
1121.5 - <52.8760.1986.87
FHHb (%)3410 - <4030.2970.8602.84
440 - <7053.3500.1580.30
SP65 Mode
pH (pH unit)186.9 - <7.27.1350.0030.05
337.2 - <7.357.3020.0010.02
1337.35 - <7.457.4020.0020.02
607.45 - <7.557.4820.0010.01
pO2 (mmHg)4930.1 - <6042.3220.1970.47
9660 - <8373.3830.8421.15
5583 - <10891.1361.3431.47
20108 - <150121.851.2040.99
ctHb (g/dL)166.5 - <87.4560.0660.89
1888 - <13.510.5980.0910.86
3613.5 - <17.514.9310.0690.46
sO2 (%)363.3 - <8062.6440.2820.45
3380 - <9491.8580.2030.22
15594 - <10097.1260.2340.24
FO2Hb (%)363.3 - <8061.6330.3060.50
5980 - <9491.7630.1810.20
13194 - <98.596.3270.1850.19
FMetHb (%)620.5 - <1.50.7770.0709.04
41.5 - <201.8250.0502.74
1220 - <5040.5750.0500.12
FCOHb (%)1561 - <51.3170.0634.78
65 - <3532.6830.0410.12
1235 - <5040.3670.0580.14
FHHb (%)1121.5 - <52.8760.1986.87
Parameter (unit)NTest intervalMeanRepeatability
SDCV%
3010 - <4031.0600.2920.94
840 - <7051.9630.1370.26

Table 4: Precision results using whole blood

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N: Number of data points for analysis Test interval: Range of values studied SD: Standard Deviation CV%: %Coefficient of Variation

Method comparison

Bias was determined by conducting a method comparison study in general accordance with CLSI EP09c, 3rd Edition, Measurement Procedure Comparison and Bias Estimation Using Patient Samples. The comparator device was the ABL90 FLEX PLUS analyzer as it was designed at the time of the clearance of K160153, in terms of its characteristics related to analytical performance. Testing was conducted using both arterial and venous blood, and in both samples collection modes: syringe/S65 mode and short probe/SP65 mode. Analysis was performed by linear regression over the reportable range. Results are presented in Table 5 and Table 6.

Table 5: Method comparison results using reportable ranges specified in the protocol

ParameterBloodtypeModenMin-maxInterceptSlopeR2MedicaldecisionpointBias atMD
pO2(mmHg)AS6522232.7-4760.7200.9950.99983.0000.344
ASP6521632.5-471-0.0651.0020.9980.119
pO2(mmHg)VS6519130.1-4760.0440.9940.999-0.454
VSP6519230.1-471-0.1941.0010.999-0.128
pH(pHscale)AS652266.848-7.7970.0150.9980.9997.350-0.003
ASP652206.843-7.7960.0250.9960.999-0.003
pH(pHscale)VS652356.848-7.7970.0190.9970.999-0.003
VSP652256.843-7.7960.0140.9980.999-0.003
sO2(%)AS652133.3-100-0.2351.0050.99994.0000.193
ASP652043.4-100-0.0331.0031.0000.280
sO2(%)VS652223.3-99.3-0.0781.0000.998-0.083
VSP652123.4-99.2-0.0401.0000.998-0.003
FO2Hb(%)AS652023.3-98.5-0.3191.0060.99994.0000.235
ASP651923.4-98.5-0.0751.0030.9990.210
FO2Hb(%)VS652223.3-98-0.0210.9990.998-0.136
VSP652133.4-98.10.0830.9970.998-0.180
FHHb(%)AS651311.4-95.8-0.0411.0031.00010.000-0.011
ASP651191.4-95.4-0.1591.0001.000-0.156
FHHb(%)VS652203.1-95.80.0511.0000.9980.056
VSP652112.8-95.40.0041.0000.9980.001
FCOHb(%)AS651331-87.6-0.2371.0011.00010.000-0.223
ASP651231-90.3-0.3590.9930.999-0.429
FCOHb(%)VS651971-87.6-0.3941.0030.999-0.360
VSP651891-90.3-0.4090.9940.999-0.474

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ParameterBlood typeModenMin-maxInterceptSlopeR2Medical decision pointBias at MD
FMetHb (%)AS65320.5-86-0.2391.0081.0001.500-0.227
SP65260.5-86-0.3161.0121.000-0.298
VS65280.5-86-0.2091.0071.000-0.198
SP65270.5-86-0.2221.0101.000-0.206

A: Arterial

V: Venous

Min-max: Range of values measured

Table 6: Method comparison results, arterial and venous combined, additional medical decision levels

ParameternInterceptSlopeR2MedicaldecisionpointBias at MD
S65 Mode
COHb (%)322-0.3321.0020.99910.000-0.307
25.000-0.271
200.00-2.028
HHb (%)338-0.0231.0030.99910.0000.005
5.000-0.009
36.0000.013
MetHb (%)49-0.2291.0081.0001.500-0.217
20.000-0.075
146.000.290
O2Hb (%)411-0.4921.0070.99994.0000.160
80.0000.063
pH (pH scale)4420.0180.9970.9987.350-0.003
7.450-0.003
pO2 (mmHg)4010.1110.9990.99983.0000.002
108.00-0.031
sO2 (%)422-0.4411.0060.99994.0000.134
80.0000.048
tHb (g/dL)4270.0151.0060.9948.4000.068
17.5000.126
SP65 Mode
COHb (%)305-0.3940.9930.99910.000-0.462
25.000-0.564
200.00-2.045
HHb (%)318-0.1171.0030.99910.000-0.089
5.000-0.103
36.000-0.169
MetHb (%)42-0.2901.0121.0001.500-0.272
20.000-0.055
146.000.259

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ParameternInterceptSlopeR2MedicaldecisionpointBias at MD
O2Hb (%)393-0.3811.0050.99994.0000.123
O2Hb (%)393-0.3811.0050.99980.0000.048
pH (pH scale)4270.0230.9960.9997.350-0.003
pH (pH scale)4270.0230.9960.9997.450-0.003
pO2 (mmHg)396-0.1661.0030.99983.0000.042
pO2 (mmHg)396-0.1661.0030.999108.000.105
sO2 (%)404-0.3951.0060.99994.0000.212
sO2 (%)404-0.3951.0060.99980.0000.122
tHb (g/dL)4120.0691.0010.9968.4000.076
tHb (g/dL)4120.0691.0010.99617.5000.084

Interference

Interfering substances were evaluated based on testing conducted in general accordance with CLSI, EP07, Interference Testing in Clinical Chemistry, 3rd Edition, and CLSI EP37, Supplemental Tables for Interference Testing in Clinical Chemistry, 1* Edition. The interference testing consists of two parts: paired-difference and dose-response studies. The paired-difference study was conducted on a large panel of likely interferents, using clinically significant amount of the interferents. Dose-response studies were only conducted in cases where a clinically significant interferent effect was noted during the paired different study. Table 7 summarizes the testing that was performed. Specific values for level of interference are described in Table 8.

InterferentpHpO2tHbsO2FO2HbFHHbFCOHbFMetHb
Intralipid--××××××
Hemolysis--------
Bilirubin (unconj)-----×--
Bilirubin (conj)-----×--
Biotin--------
Propofol--------
Potassium @ high level--------
Sodium @ high level--------
Calcium @ high level--------
pH @ low level-------×
pH @ high level-------×
Betacarotene--------
Cardio green = indocyanine green-----×-×
Cyanocobalamin--×-×-××
Evans Blue--------
HiCN--××××××
Hydroxo-cobalamine hydrochloride--×-××××

Table 7: Interference testing

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InterferentpHpO2tHbSO2FO₂HbFHHbFCOHbFMetHb
Methylene BlueXXXXXX
Patent Blue V = sulphan Blue---X--
Rifampicin------
SHbXXXXXX
Sodium Nitroprusside dihydrate---X--
Triglyceride---X-X
HbF (fetal hemoglobin)------
Fluoroescein-XXXXXX

Key

Image /page/14/Figure/3 description: The image shows a legend describing the meaning of different colors in a chart or table. The first entry indicates that the color white represents 'No clinically significant interference'. The second entry indicates that the color gray represents 'Clinically significant interference'. The third entry indicates that the color light red represents 'Interferent not relevant to be tested for this parameter'.

Image /page/14/Picture/4 description: The image shows two rows of a table. The first row has a dash symbol in the right cell, and the second row has an "X" symbol in the right cell. The left cells of both rows contain the word "ference".

Table 8: Interference values

InterferentMaximum testconcentrationHighestconcentration levelwhere interferencewas not significantImpact on result formaximum testconcentration
ctHb (test level: 10 g/dL)
Cyanocobalamin200 mg/dL25 mg/dL1.44 g/dL *
Fluorescein40 mg/dL30 mg/dL-0.72 g/dL *
HiCN30%12%1.2 g/dL *
Hydroxo-cobalaminehydrochloride200 mg/dL25 mg/dL2.66 g/dL *
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL0.38 mg/dL-3.94 g/dL *
SHb10%5%-0.86 g/dL **
ctHb (test level: 20 g/dL)
Cyanocobalamin200 mg/dL150 mg/dL0.81 g/dL *
Fluorescein40 mg/dL30 mg/dL-1.95 g/dL *
HiCN30%10%2.4 g/dL *
Hydroxo-cobalaminehydrochloride200 mg/dL50 mg/dL2.66 g/dL *
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL0.75 mg/dL-4.15 g/dL *
SHb10%2.5%-1.38 g/dL **
sO2 (test level: 90%)
Fluorescein40 mg/dL20 mg/dL-5.62%*
InterferentMaximum testconcentrationHighestconcentration levelwhere interferencewas not significantImpact on result formaximum testconcentration
HICN30%6.7%-13%*
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL0.75 mg/dL3.36%*
sO2 (test level: 100%)
Fluorescein40 mg/dL10 mg/dL-6.58%*
HICN30%6.3%-14%*
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL1.5 mg/dL4.40%*
FO2Hb (test level: 90%)
Cyanocobalamin200 mg/dL150 mg/dL-7.1%*
Fluorescein40 mg/dLNo interference2.4%*
HICN30%3.1%-37%*
Hydroxo-cobalaminehydrochloride200 mg/dL38 mg/dL-14.7%*
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL1.5 mg/dL27.0%*
SHb10%5%-7.9%**
FO2Hb (test level: 100%)
Cyanocobalamin200 mg/dL100 mg/dL-8.5%*
Fluorescein40 mg/dL20 mg/dL9.16%*
HICN30%3.2%-40%*
Hydroxo-cobalaminehydrochloride200 mg/dL38 mg/dL-16.7%*
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL1.1 mg/dL34.3%*
SHb10%5%-14.6%**
FHHb (test level: 2.4%)
Bilirubin (unconj)0.684 mmol/L40 mg/dLNo interference-0.26%
Bilirubin (conj)0.475 mmol/L40 mg/dLNo interference-0.44%
Cardio green (indocyanine green)3 mg/dL0.75 mg/dL-1.16%
Fluorescein40 mg/dL10 mg/dL7.68%*
HICN30%3.6%8.9%*
InterferentMaximum testconcentrationHighestconcentration levelwhere interferencewas not significantImpact on result formaximum testconcentration
Hydroxo-cobalaminehydrochloride200 mg/dLNo interference-0.88%*
Intralipid2000 mg/dL800 mg/dL;No measurementresult reported above1600 mg/dL.Error message"Turbidity too high."
Methylene Blue6 mg/dL0.38 mg/dL-4.44%*
Patent Blue V (sulphan Blue)1 mg/dL0.06 mg/dL-1.78%
SHb10%0.5%34.5%**
Sodium nitroprusside dihydrate87 µg/LNo interference-0.08%
Triglyceride1600 mg/dL800 mg/dL1.42%
FHHb (test level: 10%)
Bilirubin (unconj)0.684 mmol/L40 mg/dL0.17 mmol/L10 mg/dL-0.82%*
Bilirubin (conj)0.475 mmol/L40 mg/dL0.06 mmol/L5 mg/dL-0.88%*
Cardio green (indocyanine green)3 mg/dL0.75 mg/dL-2.0%
Fluorescein40 mg/dL5 mg/dL7.34%*
HiCN30%4.5%6.1%*
Hydroxo-cobalaminehydrochloride200 mg/dL150 mg/dL-1.26%*
Intralipid2000 mg/dL1200 mg/dL;No measurementresult reported above1600 mg/dL.Error message"Turbidity too high."
Methylene Blue6 mg/dL0.38 mg/dL-1.58%*
Patent Blue V (sulphan Blue)1 mg/dL0.006 mg/dL-0.98%
SHb10%2.5%17.2%**
Sodium nitroprusside dihydrate87 µg/L22 µg/L-0.52%
Triglyceride1600 mg/dL1200 mg/dL1.20%
FCOHb (test level: 1%)
Cyanocobalamin200 mg/dL50 mg/dL1.7%*
Fluorescein40 mg/dL2.5 mg/dL-10.64%*
HiCN30%3.4%6.3%*
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dLNo interference0.64%*
SHb10%1.25%1.08%**
FCOHb (test level: 10%)
Cyanocobalamin200 mg/dL100 mg/dL1.1%*
Fluorescein40 mg/dL3.75 mg/dL-10.84%*
HiCN30%9.6%2.9%*
InterferentMaximum testconcentrationHighestconcentration levelwhere interferencewas not significantImpact on result formaximum testconcentration
Intralipid2000 mg/dL1600 mg/d;LNo measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL1.5 mg/dL1.88%*
SHb10%2.5%1.58%**
FMetHb (test level: 1.0%)
Cardio green (indocyanine green)3 mg/dL1.5 mg/dL-1.48%
Cyanocobalamin200 mg/dL12.5 mg/dL5.44%*
Fluorescein40 mg/dL30 mg/dL-9.88%*
HiCN30%1.1%24%*
Hydroxo-cobalaminehydrochloride200 mg/dL8 mg/dL13.1%*
Intralipid2000 mg/dL1200 mg/dLNo measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL0.08 mg/dL-33%*
pH low6.8No interference0.96%
pH high8.0No interference-0.76%
SHb10%No interference-0.7%**
Triglyceride1600 mg/dL1200 mg/dL0.96%
FMetHb (test level: 10%)
Cardio green (indocyanine green)3 mg/dL1.5 mg/dL-1.26%
Cyanocobalamin200 mg/dL12.5 mg/dL4.28%*
Fluorescein40 mg/dL30 mg/dL-11.2%*
HiCN30%1.3%20%*
Hydroxo-cobalaminehydrochloride200 mg/dL9 mg/dL13.3%*
Intralipid2000 mg/dL1600 mg/dL;No measurementresult reported above1600 mg/dLError message"Turbidity too high."
Methylene Blue6 mg/dL0.08 mg/dL-35%*
pH low6.8Interference below7.01.3%
pH high8.0Interference above7.7-1.52%
SHb10%0.5%-5.8%**
Triglyceride1600 mg/dLNo interference0.82%

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RADIOMETER B

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RADIOMET

  • The result at maximum test concentration is marked with error message "OXI spectrum mismatch"

** The result at maximum test concentration is marked with error message "Warning, SHb detected"

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Conclusion

The results above demonstrate the acceptable analytical performance of the ABL90 FLEX PLUS System and its substantial equivalence to its predicate.

§ 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.