RAPIDPoint® 400/405/500 systems are intended for in vitro testing of pleural fluid samples for the pH parameter. Test systems are intended for use in point of care or laboratory settings.

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 < 7.3 are referred to as complicated parapneumonic effusions, and are exudative in nature.

Device Description

The RP400/405/500 system is a point-of-care and laboratory testing blood gas analyzer and currently measures a variety of parameters. With this planned release of software, the ability to measure pH in Pleural Fluid will be added to the system.

The pleural fluid pH measurement provides important information for the diagnosis of exudative pleural effusions. The RAPIDPoint® 400/405/500 system is intended for in vitro testing of pleural fluid samples for the pH parameter. This test system is intended for use in point of care or laboratory settings. Pleural fluid pH testing follows the same principles as whole blood pH testing. The notation of pH expresses the hydrogen ion activity in a solution as the negative logarithm of the hydrogen ion concentration. The pleural fluid pH measurement uses the potentiometric method using ion selective electrode (ISE) technology.

AI/ML Overview

The provided text describes the analytical performance of the RAPIDPoint® 400/405/500 Systems for measuring pH in pleural fluid. The device is a blood gas analyzer that has been granted a 510(k) clearance (K122539) to include pleural fluid pH measurement.

Here's a breakdown of the requested information based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The submission does not explicitly state pre-defined acceptance criteria for the method comparison study in terms of specific ranges for slope, intercept, RMSE, or r². However, it states that "The results for the RP405 vs. the predicate device met the acceptance criteria" and "The results for the RP400 and RP500 vs. the predicate device met the acceptance criteria." This implies that internal acceptance criteria were used and successfully met.

For the precision studies, the acceptance criteria are not explicitly mentioned in terms of threshold values for WRSD, %WRCV, Total SD, or %Total CV. The tables simply report the measured precision values.

Therefore, the table below will present the reported performance, with the understanding that implied acceptance criteria were met.

Study Type	Feature	Acceptance Criteria (Implied/Met)	Reported Device Performance (RP400/405/500)
Method Comparison	Slope	Implicitly met	RP400: 1.066, RP500: 1.059
(vs. Predicate Device ABL 835 FLEX)	Intercept	Implicitly met	RP400: -0.437, RP500: -0.373
	RMSE	Implicitly met	RP400: 0.014, RP500: 0.016
	Coefficient of Determination (r²)	Implicitly met	RP400: 0.99, RP500: 0.99
Linearity	Slope	Implicitly met	RP400: 1.066, RP405: 1.008, RP500: 1.059
	Intercept	Implicitly met	RP400: -0.437, RP405: -0.009, RP500: -0.373
	r²	Implicitly met	RP400: 0.99, RP405: 0.95, RP500: 0.99
Precision with Controls	WRSD	Implicitly met	0.002 - 0.004
	% WRCV	Implicitly met	0.0 - 0.1
	Total SD	Implicitly met	0.002 - 0.004
	% Total CV	Implicitly met	0.0 - 0.1
Precision with Pleural Fluid	WRSD	Implicitly met	0.006 - 0.012
	% WRCV	Implicitly met	0.1 - 0.2
	Total SD	Implicitly met	0.008 - 0.019
	% Total CV	Implicitly met	0.1 - 0.3
Precision with Pleural Fluid (POC Study)	WRSD	Implicitly met	0.011 - 0.019
	% WRCV	Implicitly met	0.15 - 0.26
	Total SD	Implicitly met	0.02 - 0.03
	% Total CV	Implicitly met	0.21 - 0.42

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

Method Comparison and Linearity Test Set:
- RP405 vs. ABL835 FLEX: The sample size for the RP405 is not explicitly stated in the provided table for this comparison, only indicated by a missing number in a seemingly truncated table. However, other entries in the complete table indicate n values (e.g. 122 for RP400 and RP500).
- RP400 and RP500 vs. ABL835 FLEX: n = 122 pleural fluid samples per device (RP400 and RP500).
- Data Provenance: The specimens were "de-identified, leftover samples, collected both prospectively and retrospectively." The specific country of origin is not mentioned. Less than 20% of the samples were "altered samples."
Precision Test Set (Controls): n = 80 per control level per device (RP400, RP405, RP500).
Precision Test Set (Pleural Fluid - Lab Study): n = 80 per fluid level per device (RP400, RP405, RP500).
Precision Test Set (Pleural Fluid - Point of Care Study): n = 45 per fluid level per device (RP400, RP405, RP500).

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

This information is not provided in the document. The ground truth for the method comparison appears to be the measurements obtained from the predicate device (ABL835 FLEX Analyzer), which is itself a medical device measuring pH. For linearity and precision studies, it's based on the intrinsic performance of the devices against known buffered samples or the average of multiple measurements. There's no mention of human expert ground truth establishment for these analytical performance studies.

4. Adjudication Method for the Test Set

This is not applicable as the studies are analytical performance studies comparing device measurements or assessing device precision, not studies involving human interpretation or clinical adjudication.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This is not applicable. The device is an automated in vitro diagnostic instrument for measuring pH. It does not involve human readers interpreting images or data that would be augmented by AI.

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

Yes, the entire study is a standalone performance evaluation of the RAPIDPoint® 400/405/500 Systems. The device operates automatically to measure pH in pleural fluid samples. The data presented demonstrates the analytical performance of the instrument, not its performance in conjunction with a human operator for interpretation.

7. The Type of Ground Truth Used

Method Comparison: The "predicate device" (ABL835 FLEX Analyzer With Pleural pH, 510(k) K110416) served as the reference for ground truth in the method comparison studies.
Precision Studies: For precision, the "mean" values for controls and pleural fluid samples served as the reference against which the variability was measured. These controls were buffered and CO2 tension was altered to three pH levels, implying controlled, known values.
Linearity Study: Linearity was assessed using "linearity data for pleural fluid collected in the comparison study," which implies the predicate device's readings or a controlled series of samples with known pH values served as the reference.

8. The Sample Size for the Training Set

This information is not provided. As this is a 510(k) submission for a blood gas analyzer adding a new parameter, the underlying technology (ion selective electrode) is well-established. It's unlikely that a "training set" in the context of machine learning was used in the same way one would for an AI-powered device. The device's calibration and internal algorithms are based on established electrochemical principles, not a data-driven training process in the sense of AI.

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

This information is not provided and is likely not applicable in the context of this type of device. The calibration of the pH electrode in the device is performed using "2 point calibration using automated on-board reagent" with targeted calibration points of 6.8 and 7.4 pH. These are well-defined chemical standards that serve as the "ground truth" for the device's internal calibration.

Summary

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K122539

510(k) Summary

APR 1 9 2013

This 510(k) summary is being submitted in accordance with the requirements of 21 CFR 807.92.

1.0 Submitter Information

Owner

Siemens Healthcare Diagnostics, Inc. Point of Care (POC) Business Unit 2 Edgewater Drive Norwood, MA 02062

Contact

Primary: Amy Goldberg Regulatory Technical Specialist 781-269-3544 TEL

Secondary: Steven Goldberg Manager Regulatory Affairs steven.goldberg@siemens.com

Date Summary Prepared

2.0 Device Information

Proprietary Name	RAPIDPoint® 400/405/500 Systems
Common Name	Blood Fluid = U

Common Name Pleural Fluid pH Main Classification Name Blood gases (PCO2, PO2) and blood pH test system 21 CFR 862.1120, Class II Product Code CHL

781-269-3941 TEL

March 21, 2013

Subsequent Classifications

3.0 Predicate Device

	Predicate Device
Device Name	ABL835 FLEX Analyzer With Pleural pH
Common Name	Pleural Fluid pH
510(k) Number	K110416
Manufacturer	Radiometer Medical ApS

4.0 Device Description

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5.0 Intended Use Statement

RAPIDPoint® 400/405/500 systems are intended for in vitro testing of pleural fluid samples for the pH parameter. Test systems are intended for use in point of care or laboratory settings.

The pH measurement of pleural fluid can be a clinically useful tool in the management of patients with parapneumonic effusions.

Feature	RAPIDPoint® 400/405/500 PleuralFluid pH(Modified Device)	ABL835 FLEX AnalyzerWith Pleural pH(Predicate Device)
Intended Use	RAPIDPoint® 400/405/500 systems areintended for in vitro testing of pleuralfluid samples for the pH parameter. Testsystems are intended for use in point ofcare or laboratory settings.The pH measurement of pleural fluid canbe a clinically useful tool in themanagement of patients withparapneumonic effusions.The following critical value applies topleural fluid pH: pH > 7.3 is measured inuncomplicated parapneumoniceffusions. All pleural fluids with a pHmeasurement < 7.3 are referred to ascomplicated parapneumonic effusions,and are exudative in nature.	Same without point of caretesting.
Principle ofOperation	Blood gas analyzer	Same
TestPrinciple	Potentiometric	Same
MeasuredParameter	pH in Pleural Fluid	Same

Summary Comparison of Technological Characteristics 6.0

Siemens Healthcare Diagnostics Inc. RP400/405/500 Pleural Fluid pH / Traditional 510(k)

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Feature	RAPIDPoint® 400/405/500 PleuralFluid pH(Modified Device)	ABL835 FLEX AnalyzerWith Pleural pH(Predicate Device)
ParameterNomenclature	pH in Pleural Fluid	Same
Technology	Pleural fluid pH measurement uses thepotentiometric method using ionselective electrode (ISE) technology	Same
SpecimenType	Pleural Fluid	Same
ExpectedValues*†‡	The following critical value applies topleural fluid pH: pH > 7.3 is measured inuncomplicated parapneumonic effusions.All pleural fluids with a pH measurement< 7.3 are referred to as complicatedparapneumonic effusions, and areexudative in nature.	Same
ReportedOutput	pH units	Same
ReportingRange	7.000 to 7.500	Same
Calibration	2 point calibration using automated on-board reagent	2 point liquid calibration
Main TestSteps	Select 'Pleural Fluid' button.Collect sample, insert device into sampleluer, & select "Start"	Same ('Other Fluids' button)

6 0 Summary Comparison of Technological Characteristics

Lesho EP, Roth BJ. Chest (1997) 5, 1291 - 1292.

† Chandler TM, McCoskey EH, Byrd RP, Roy TM. Southern Medical Journal (1999) 92, 214 - 217.

Hooper C, Lee YC, Maskell N. BTS Pleural Guideline Group. Thorax (2010) 65: Suppl 2: ii4-17.

7.0 Test Principle

Pleural fluid pH testing follows the same principles as whole blood pH testing. The notation of pH expresses the hydrogen ion activity in a solution as the negative logarithm of the hydrogen ion concentration. The pleural fluid pH measurement uses the potentiometric method using ion selective electrode (ISE) technology.

8.0 Performance Characteristics

Analytical Performance

a. Precision / Reproducibility

The Precision study consisted of two runs per day, an n=2 per sample run on the RP400/405/500 and performed over the course of 20 days for an n of 80. Pleural fluid samples were buffered and the tension of CO2 altered to three levels of pH within 7.0 to 7.5 units. All were then stored frozen until the time of use.

Each run performed in Pleural Fluid mode and spaced a minimum of two hours apart, contained Calibration Verification Material (CVM) and pleural fluid samples. Complete QC

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Level 2 was analyzed within the center of each run to verify instrument performance. Results for CVM controls and pleural fluid pH are contained in the tables below:

Level	n	Mean	WRSD*	% WRCV	Total SD†	% Total CV
RP400
2	80	7.091	0.003	0.0	0.004	0.1
3	80	7.312	0.002	0.0	0.002	0.0
RP405
2	80	7.102	0.004	0.1	0.004	0.1
3	80	7.327	0.002	0.0	0.003	0.0
RP500
2	80	7.098	0.002	0.0	0.004	0.1
3	80	7.324	0.002	0.0	0.004	0.0

Precision with Controls

Precision with Pleural Fluid

Level	n	Mean	WRSD*	% WRCV	Total SD†	% Total CV
RP400
Low	80	7.102	0.010	0.1	0.011	0.2
Mid	80	7.284	0.010	0.1	0.011	0.2
High	80	7.469	0.007	0.1	0.008	0.1
RP405
Low	80	7.102	0.009	0.1	0.011	0.2
Mid	80	7.289	0.012	0.2	0.012	0.2
High	80	7.473	0.007	0.1	0.007	0.1
RP500
Low	80	7.08	0.006	0.1	0.016	0.2
Mid	80	7.26	0.011	0.2	0.018	0.2
High	80	7.45	0.011	0.1	0.019	0.3

WRSD = within-run standard deviation

% WRCV = percent within-run coefficient of variation

† Total SD = total standard deviation

% Total CV = percent total coefficient of variation

The sponsor performed a Precision study using typical point of care (POC) operators at three sites running pleural fluid samples on the RP400/405/500 systems. The testing was performed in Pleural Fluid mode over a minimum of 1 day, 3 runs per day, with each run separated by two hours to simulate several days and 5 replicates per run for each of the three levels across the reportable pleural fluid pH range (Low, Mid, High) for a total N = 45. All pleural fluid samples were stored frozen at -70°C or below individually until the time of use. Results are contained in the table below:

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Level	n	Mean	WRSD*	% WRCV	Total SD†	% Total CV
RP400
Low	45	7.121	0.014	0.19	0.03	0.37
Mid	45	7.295	0.012	0.16	0.02	0.21
High	45	7.464	0.019	0.26	0.02	0.28
RP405
Low	45	7.110	0.019	0.26	0.03	0.42
Mid	45	7.289	0.011	0.15	0.02	0.21
High	45	7.463	0.017	0.23	0.02	0.28
RP500
Low	45	7.109	0.013	0.19	0.02	0.35
Mid	45	7.285	0.013	0.18	0.02	0.24
High	45	7.463	0.014	0.18	0.02	0.22

Precision with Pleural Fluid (Point of Care Study - Three Sites)

WRSD = within-run standard deviation % WRCV = percent within-run

coefficient of variation

† Total SD = total standard deviation %Total CV = percent total coefficient of variation

b. Detection Limit

Detection limit for pleural fluid pH was established in the method comparison study. Section e. below, and for whole blood pH in the previously cleared submission (K002738). The measuring range for pleural fluid pH samples is 7.0 to 7.5.

c. Analytical Specificity

Analytical specificity was established in the previously cleared submission (K002738).

d. Linearity/assay reportable range

Linearity data for pleural fluid collected in the comparison study (see Section e. Method Comparison Studies below) was used to demonstrate linearity on the RP400/405/500 analyzer. Linear regression analysis of the results yielded the following:

RP400: y = 1.066x (-0.437), r2 = 0.99 RP405: y = 1.008x (-0.009), r2 = 0.95 RP500: y = 1.059x (-0.373), r2 = 0.99

Comparison Studies

e. Method Comparison with Predicate Device

The sponsor performed method comparison studies at 3 point of care (POC) clinical sites using at least 3 typical POC operators and one RP405 instrument per site vs. the ABL835 FLEX predicate device. Multiple cartridges and reagent lots were used for this study. All sites were data collection (testing) sites. All specimens were de-identified, leftover samples, collected both prospectively and retrospectively. Less than 20% of the samples

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in the study were altered samples. Linear regression analysis was used to determine the coefficient of determination (~) and to determine the slope and intercept. The results for the RP405 vs. the predicate device met the acceptance criteria and are contained in the table below:

	Statistical Summary of RP405 vs. an ABL 835 FLEX System
	with the first for the first and the many of the country of the county of the first of the first of the first of the first of the first of the first of the first of the first

SIOBE---------------		DRICC1 18.2.		.
	0 000	1 Ann(	(	AGC
	And Controller Children Collection Company Controller Company Company Company Company Company Company Company Company Company Company Company Company Company Company Company	A B A B A B A B A B . A B . A

RMSE = Root Mean Square Error

r = Coefficient of Determination

The sponsor performed an additional Method Comparison study using typical POC operators at three sites with a minimum of 40 pleural fluid samples per site run in duplicate across the pleural fluid pH reporting range of 7.0 to 7.5 on the RP400 and RP500 vs. the ABL835 FLEX predicate device. Linear regression analysis was used to determine the coefficient of determination (r2) and to determine the slope and intercept. The results for the RP400 and RP500 vs. the predicate device met the acceptance criteria and are contained in the table below:

Statistical Summary of RP400. RP500 vs. an ABL 835 FLEX System

n	Slope	Intercept	RMSE	r2	Sample Range
RP400
122	1.066	-0.437	0.014	0.99	7.011 - 7.458
RP500
122	1.059	-0.373	0.016	0.99	7.011 - 7.452

RMSE = Root Mean Square Error

2 = Coefficient of Determination

f. Matrix Comparison Not applicable.

Clinical Studies

g. Clinical Sensitivity Not applicable

h. Clinical Specificity Not applicable

Clinical Cut-off

Not applicable

Expected Values *†‡/ Reference Range

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Lesho EP. Roth BJ. Chest (1997) 5, 1291 - 1292.

Chandler TM, McCoskey EH, Byrd RP, Roy TM. Southern Medical Journal (1999) 92, 214 - 217. + Hooper C, Lee YC, Maskell N. BTS Pleural Guideline Group. Thorax (2010) 65:Suppl 2: ii4-17.

9.0 Instrument Name:

RAPIDPoint 400/405/500 Blood Gas Analyzer

10.0 System Descriptions

Modes of Operation

Pleural Fluid (PF) pH is a new sample type offered on the RAPIDPoint® 400/405/500 (RP400/405/500) blood gas system. The RP400/405/500 system is a point-of-care and laboratory testing blood gas analyzer. Single testing.

Specimen Identification

Samples are identified by barcode.

Specimen Sampling and Handling

Users follow the same sample handling process already in place for measuring other parameters on the blood gas analyzer. Users can analyze samples using the sample collection devices and pleural fluid is collected in a syringe.

Calibration

There is no unique calibration measurement for pleural fluid pH. The pH calibration measurement is used for pleural fluid pH. The targeted calibration points for pH are:

. Calibration Point: 6.8
. Slope Point: 7.4

Quality Control

No unique RapidQC® Complete or CVM® control materials are required for pleural fluid pH. The AutomaticQC cartridge available with the release of the System Software version 3.8 (2.1 on RP500) supports the use of pleural fluid pH.

No new or modified Quality Control (QC) procedures are required to measure pleural fluid pH. The external quality controls, RAPID QC Complete, used in validation are commercially available and were cleared under the 510(k) number K970956.

Other Supportive Instrument Performance Characteristics Data Not Covered in the "Performance Characteristics" Section above:

None

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11.0 Conclusion

The results of these studies demonstrate that the RAPIDPoint 400/405/500 blood gas analyzer is similar to the predicate in both Technological Characteristics and Intended Use and is therefore substantially equivalent. The data presented is a summary of external clinical evaluation, internal laboratory evaluation, and software development information. The RAPIDPoint 400/405/500 performance was shown to be substantially equivalent to the predicate device.

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/8/Picture/1 description: The image shows the logo for the Department of Health & Human Services (USA). The logo consists of a stylized eagle or bird-like figure with three curved lines representing its body and wings. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES-(USA)" is arranged in a circular fashion around the bird-like figure.

Public Health Service

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

April 19, 2013

Siemens Healthcare Diagnostics, Inc. C/O Amy Goldberg Point of Care (POC) Business Unit 2 Edgewater Drive NORWOOD MA 02062

Re: K122539

Trade/Device Name: RAPIDPoint® 400/405/500 Systems Regulation Number: 21 CFR 862.1120 Regulation Name: Blood gases (PCO2, PO2) and blood pH test system Regulatory Class: II Product Code: CHL Dated: March 21, 2013 Received: March 22, 2013

Dear Ms. Goldberg:

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. 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 requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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Page 2 Goldberg

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.

Sincerely yours,

Carol C. Benson -S for

Courtney H. Lias, Ph.D. Director Division of Chemistry and Toxicology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known): K122539

Device Name: RAPIDPoint® 400/405/500 Systems

Indications for Use:

RAPIDPoint® 400/405/500 systems are intended for in vitro testing of pleural fluid samples for the pH parameter. Test systems are intended for use in point of care or laboratory settings.

The pH measurement of pleural fluid can be a clinically useful tool in the management of patients with parapneumonic effusions.

Prescription Use X (21 CFR Part 801 Subpart D) And/Or

Over the Counter Use (21 CFR Part 801 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE; CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of In Vitro Diagnostics and Radiological Health (OJR)

Yung W.D.Chan -S

Division Sign-Off Office of In Vitro Diagnostics and Radiological Health

510(k) K122539

Regulation Number and Section

§ 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.