Interpretation and Clinical Significance of Arterial Blood Gas Analysis in Respiratory and Laboratory Medicine-An Updated Review
Published 2025-03-10
Keywords
- Arterial blood gas, pH, PaCO₂, PaO₂, acid–base balance, ventilation, oxygenation, A–a gradient, P/F ratio, quality control.
This work is licensed under a Creative Commons Attribution 4.0 International License.
Abstract
Background: Arterial blood gas (ABG) analysis is a cornerstone diagnostic tool that provides direct assessment of ventilation, oxygenation, and acid–base balance. Despite advancements in non‑invasive monitoring, ABG remains the gold standard for evaluating critically ill patients and guiding therapeutic decision‑making.
Aim: This review aims to summarize updated principles, specimen requirements, analytical procedures, interpretive strategies, and clinical applications of ABG analysis in respiratory and laboratory medicine.
Methods: A comprehensive narrative review of current practices in ABG analysis was undertaken, focusing on physiological principles, pre‑analytical variables, analyzer technology, quality control, and interpretative frameworks. Clinical examples were included to illustrate systematic interpretation.
Results: ABG interpretation integrates pH, PaCO₂, PaO₂, bicarbonate, and oxygen saturation to distinguish respiratory and metabolic disorders, assess compensation, and evaluate oxygenation. Accurate results require strict sample handling, anaerobic collection, rapid processing, and appropriate anticoagulation. Modern analyzers enable precise measurement through advanced calibration systems, barometric correction, and automated quality control. Pre‑analytical errors—including air exposure, improper heparin use, and delays in processing—remain major sources of inaccuracy. Clinically, ABG findings guide management of acute respiratory failure, shock, metabolic derangements, and ventilation strategies. Tools such as the A–a gradient, P/F ratio, and structured interpretation methods (e.g., Romanski method) enhance diagnostic reliability.
Conclusion: ABG analysis is indispensable for evaluating respiratory and metabolic status across emergency, critical care, and chronic disease management. Accurate sampling, rigorous analytical processes, and structured interpretation significantly improve clinical outcomes.