Test Overview
Test Methodology

Blood gas analyzer (electrode based method)

Test Usage

Pleural fluid pH is a key component in the diagnosis of pleural infections (including tuberculosis), rheumatoid pleural effusion, and esophageal rupture, as well as management of patients with pleural effusions. A low pleural fluid pH is associated with high metabolic activity in the pleural space, and provides supportive evidence for pleural infections. Additionally, in malignant pleural effusions, low pleural fluid pH correlates with a poor prognosis.

Reference Range *

pH > or = 7.3

Note: Analytical measurement range for the pH using the blood gas analyzer (electrode based method) is 6.7-7.8 . pH results >7.8 will be reported as ".7.8", and are within the reference range.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details
Days Set Up
Daily, 24 hours, 7 days a week (including holidays)
Analytic Time

1 - 4 hrs

Soft Order Code
MiChart Code
Chemical Pathology
Specimen Requirements
Collection Instructions

Collect pleural fluid in blood gas syringe, clean plastic container or red top tube with no preservatives. Deliver to laboratory immediately after collection. Delays in the delivery of the specimen to the laboratory, and/or delayed analysis may significantly increase the pH.

Normal Volume
0.5 mL
Minimum Volume
0.3 mL
Rejection Criteria
Collection cups and specimen tubes will be rejected. Any syringes with needles attached will also not be accepted.

CPT Code
Fee Code