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Real-Time, Semi-Automated Fluorescent Measurement of the Airway Surface Liquid pH of Primary Human Airway Epithelial Cells
Published on: June 13, 2019
Improving Pleural Fluid pH Accuracy: A Quality Improvement Initiative.
Sydney M Bowmaster1, Anna E Merrill2, Nicole L Manning2
1Division of Pulmonary, Critical Care and Occupational Medicine, University of Iowa Health Care Medical Center, Iowa City, IA, United States.
Accurate pleural fluid pH measurement is crucial for diagnosing effusions. Blood gas syringes, not standard vials, ensure reliable results by maintaining anaerobic conditions, preventing pH changes.
Area of Science:
- Medical Diagnostics
- Clinical Chemistry
Background:
- Pleural fluid pH is a key diagnostic marker for pleural effusions.
- Standard practice recommends immediate analysis using a blood gas analyzer.
- Centralized laboratory services may impact the accuracy of pleural fluid pH measurements.
Purpose of the Study:
- To evaluate the impact of sample collection methods on pleural fluid pH accuracy.
- To compare pH measurements from blood gas syringes versus standard thoracentesis kit vials.
- To assess the influence of processing time and heparin on pleural fluid pH.
Main Methods:
- Collected paired pleural fluid samples from 30 patients.
- Measured fluid pH and pCO2 using a blood gas analyzer.
- Compared samples from blood gas syringes and plastic screw-top vials, analyzing effects of processing time and heparin.
Main Results:
- Samples in blood gas syringes showed significantly lower mean pH and higher mean pCO2 than those in screw-top vials (P < 0.001).
- pH differences were not dependent on cell counts.
- Neither heparin presence nor delays up to 2 hours significantly affected pH results.
Conclusions:
- Anaerobic collection in blood gas syringes is essential for accurate pleural fluid pH.
- Standard thoracentesis kit vials may lead to inaccurate pH readings.
- Optimized sample handling is critical for reliable pleural effusion diagnostics.
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