ABL90 FLEX PLUS System

The ABL90 FLEX PLUS System is a portable, automated blood gas analyzer that measures pH, oxygen partial pressure (pO2), oxygen saturation (sO2), total hemoglobin (ctHb), and hemoglobin fractions (oxyhemoglobin, carboxyhemoglobin, methemoglobin, and reduced hemoglobin) from heparinized arterial and venous whole blood samples. It is intended for use in laboratory, near-patient, and point-of-care settings by trained healthcare professionals to aid in diagnosing and treating acid-base disturbances and other blood gas-related conditions.

The ABL90 FLEX PLUS System uses identical operating principles and major components to its predicate device: potentiometry for pH measurement, optical detection for pO2, and spectrophotometry for oximetry parameters. Both devices accept 65 µL heparinized whole blood samples from Radiometer and non-Radiometer samplers in S65 mode, use the same sensor cassette and solution pack consumables, and report results over identical ranges. The key difference is that the new device removes measurements for electrolytes, glucose, lactate, and neonatal bilirubin that were available on the predicate.

Testing was conducted in general accordance with Clinical Laboratory Standards Institute (CLSI) guidelines, including CLSI EP06 (linearity), CLSI EP17-A2 (detection capability), CLSI EP39 (surrogate samples), CLSI EP05-A3 (precision), CLSI EP09c (method comparison and bias), CLSI EP07 (interference testing), and CLSI EP37 (supplemental interference tables). All cited CLSI standards are FDA-recognized consensus standards.

Substantial equivalence is supported by identical intended use (same sample types, indications, and clinical settings), identical operating principles and major components, identical performance characteristics across all measured parameters, and comprehensive analytical performance data demonstrating acceptable linearity, detection limits, precision, and accuracy versus the predicate device. The removal of electrolytes, glucose, lactate, and bilirubin measurements represents a narrowing of functionality rather than a fundamental change, and method comparison studies confirm the device produces results with negligible bias at clinically relevant decision points compared to the predicate analyzer.