ABL90 FLEX, ABL90 FLEX PLUS

• K Number: K170882
• Device Name: ABL90 FLEX, ABL90 FLEX PLUS
• Manufacturer: Radiometer Medical ApS
• Date Cleared: 2017-04-28 ( 35 days)
• Product Code: MQM , MOM
• Regulation Number: 862.1113
• Type: Traditional
• Panel: CH
• Reference & Predicate Devices: K160153 , K132691 , K050869

Intended Use

The ABL90 FLEX analyzer is an in vitro diagnostic, portable, automated analyzer that quantitatively measures neonatal bilirubin in heparinized capillary, venous and arterial whole blood.
The ABL90 FLEX analyzer 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.
Bilirubin measurements on the ABL90 FLEX analyzer are intended to aid in assessing the risk of kernicterus in neonates.

ABL90 FLEX PLUS:
The ABL90 FLEX PLUS analyzer is an in vitro diagnostic, portable, automated analyzer that quantitatively measures neonatal bilirubin in heparinized capillary, venous and arterial whole blood.
The ABL90 FLEX PLUS analyzer 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.
Bilirubin measurements on the ABL90 FLEX PLUS analyzer are intended to aid in assessing the risk of kernicterus in neonates.

Device Description

The ABL90 FLEX and ABL90 FLEX PLUS analyzers are two models of the same portable, automated system intended for in vitro testing of samples of whole blood for the parameters pH, pO-, pCO3, potassium, sodium, calcium, chloride, glucose, lactate, neonatal bilirubin, and co-oximetry parameters (total hemoglobin, oxygen saturation, and the hemoglobin fractions FO-Hb, FCOHb, FMetHb, FHHb and FHbF).
The manufacturer of the ABL90 FLEX and ABL90 FLEX PLUS is Radiometer Medical ApS.
The ABL90 FLEX and ABL90 FLEX PLUS consist of an instrument with a sensor cassette and a solution pack as the main accessories. Multiple models of sensor cassettes are available.
The various sensor cassette models for different parameter combinations. For each parameter combination, models allowing for different test load are available.
The solution pack is available in two models differing in the number of tests available.
Technology:
The ABL 90 FLEX and ABL90 FLEX PLUS electrochemical sensors are miniaturized, manufactured by film technology and integrated in a common sensor cassette. Likewise, the ABL90 FLEX and ABL90 FLEX PLUS optical oxygen sensor is integrated in the sensor cassette. A 256-pixel array spectrophotometer is used for the co-oximetry parameters and bilirubin.
Clinical Utility ctBil:
For newborns up to an age of one month the method's reportable range covers the entire reference range. Neonatal Bilirubin test is intended for use to aid in assessing the risk of kernicterus in newborns.

AI/ML Overview

The provided document is a 510(k) Premarket Notification from the FDA regarding the ABL90 FLEX and ABL90 FLEX PLUS devices for measuring neonatal bilirubin. It primarily focuses on demonstrating substantial equivalence to a predicate device, rather than defining and proving acceptance criteria as typically done for novel AI/ML medical devices.

Therefore, many of the requested points related to acceptance criteria, ground truth establishment, expert consensus, MRMC studies, and training sets are not applicable to this type of submission. This 510(k) is for an in-vitro diagnostic device that measures a chemical parameter (bilirubin) using established spectrophotometric technology, not an AI/ML-driven diagnostic or image analysis tool. The "performance" being evaluated is the analytical performance (accuracy, precision, linearity) of the device against a known predicate and reference methods, not the diagnostic performance of an algorithm.

However, I can extract the relevant information from the document that pertains to its performance evaluation.

---

Overview of Device Performance Evaluation (Not AI/ML focused)

The ABL90 FLEX and ABL90 FLEX PLUS analyzers are in vitro diagnostic devices designed to quantitatively measure neonatal bilirubin in heparinized capillary, venous, and arterial whole blood. The submission aims to extend the indicated sample types for neonatal bilirubin measurement to include arterial and venous whole blood, leveraging performance data already established for capillary whole blood in a previous 510(k) (K132691).

The core of the performance study for this specific submission is demonstrating method comparison (correlation) against a predicate device (ABL800 FLEX or ABL835 FLEX, which is part of the ABL800 FLEX family) for the new sample types.

---

Relevant Performance Information and Analysis (from the provided document):

1. A table of acceptance criteria and the reported device performance:

   • Acceptance Criteria: Not explicitly stated as pass/fail thresholds in this document for the method comparison study. The goal is to demonstrate "substantial equivalence" based on the correlation characteristics (slope, intercept, R-squared) to the predicate device. The implicit acceptance is that the correlation is strong (R-squared close to 1) and the linear relationship is close to y=x (slope close to 1, intercept close to 0), indicating comparable performance to the predicate. The FDA's determination of substantial equivalence implies these criteria were met.

   • Reported Device Performance (from Table 1: Neonatal bilirubin linear regression data for ABL90 FLEX measurements compared to ABL835 FLEX measurements):

     Parameter	Units	Slope	Intercept (mg/dL)	R²	Sy.x (mg/dL)
     ctBil All (combined samples)	mg/dL	0.97	-0.38	1.00	0.60
     ctBil Arterial All	mg/dL	0.98	-0.54	0.97	0.53
     ctBil Venous All	mg/dL	0.98	-0.32	0.98	0.62
     ctBil site 1	mg/dL	0.96	-0.18	1.00	0.57
     ctBil site 2	mg/dL	0.98	-0.71	1.00	0.58

   Interpretation: The R-squared values are very high (0.97 to 1.00), indicating a very strong linear correlation between the ABL90 FLEX and the predicate ABL835 FLEX. The slopes are close to 1 (0.96-0.98) and intercepts are close to 0 (-0.18 to -0.71 mg/dL), suggesting good agreement (i.e., minimal proportional or constant bias) between the new device and the predicate.

2. Sample size used for the test set and the data provenance:

   • Test Set Sample Sizes:
     • 44 arterial blood samples
     • 42 venous blood samples
     • 17 spiked cord blood samples
     • Total N = 103 samples (44 arterial + 42 venous + 17 spiked)
   • Data Provenance: The study was conducted at "two point-of-care sites." The document does not specify the country of origin of the data. It is a prospective method comparison study where new measurements were taken for the purpose of this submission.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

   • Not applicable in the context of an AI/ML algorithm. For this in vitro diagnostic device, the "ground truth" for the method comparison is the measurement obtained from the predicate device (ABL835 FLEX), which is itself a validated diagnostic instrument. This is an analytical performance study, not a diagnostic performance study relying on expert interpretation.

4. Adjudication method for the test set:

   • Not applicable. This study involves direct quantitative measurements of a chemical analyte, not qualitative assessments or interpretations that would require 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:

   • Not applicable. This is an in vitro diagnostic device measuring a chemical substance, not an AI-assisted diagnostic tool that would involve human readers interpreting images or data.

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

   • This is inherently a "standalone" device in its measurement function. The device itself performs the measurement and provides a numerical output. Human involvement is in operating the device and interpreting the numerical result in a clinical context, but not in assisting an algorithm to produce the measurement.

7. The type of ground truth used:

   • The "ground truth" (or reference method for comparison) was measurements obtained from another legally marketed device (predicate device, ABL835 FLEX), which is widely considered a reliable method for bilirubin measurement. For in vitro diagnostics, this is a standard approach to demonstrating substantial equivalence – showing comparable performance to an established method.

8. The sample size for the training set:

   • Not applicable. This device uses established spectrophotometric technology and is not an AI/ML device that requires a training set in the conventional sense. The "training" here would be the design and calibration of the instrument based on chemical and optical principles.

9. How the ground truth for the training set was established:

   • Not applicable. As above, no training set in the AI/ML sense.

Regulation Number and Section

§ 862.1113 Bilirubin (total and unbound) in the neonate test system.

(a)
Identification. A bilirubin (total and unbound) in the neonate test system is a device intended to measure the levels of bilirubin (total and unbound) in the blood (serum) of newborn infants to aid in indicating the risk of bilirubin encephalopathy (kernicterus).(b)
Classification. Class I.