Pulmonology Labs Brenda Beckett, PA-C Clinical Assessment II

Reminder: John’s lecture on arterial blood gases (ABGs) will be on the upcoming CA lab/rad exam.

Pleural Fluid Pleural fluid: Specimen obtained by thoracentesis. Transudate: Fluid that has passed through a normal membrane as a result of imbalanced hydrostatic and osmotic forces. Exudate: Fluid that has exuded (oozed) out of a tissue because of injury or inflammation

Pleural Fluid Transudative effusions occur when systemic factors that influence the formation and absorption of pleural fluid are altered (e.g., low serum proteins and increased pulmonary venous pressure). Exudative effusions occur when local factors that influence the formation and absorption of fluid are altered (e.g., infection and malignancy).

Pleural Fluid P Wallach –Appearance –WBC and RBC counts (for malignancy) –Glucose –Protein –LDH –Specific Gravity –Cultures – If you think infection –Cytology – looking at all cells for malignancy

Pleural Fluid LDH, protein or specific gravity of the fluid can distinguish these two. Most agree that exudates must meet one or more of the following criteria, whereas transudates meet none: Pleural fluid protein/serum protein > 0.5 or absolute value > 3g/dl. Pleural fluid/serum LDH > 0.6 or absolute value > 45% upper normal serum limit. Pleural fluid specific gravity > 1.018

D-Dimer Positive: Presence of fibrin degradation products due to significant clot formation and breakdown, but it does not tell the location or cause. Can be due to a PE, VTE or DIC. May also be due to recent surgery, trauma, infection, liver disease, pregnancy, eclampsia, heart disease, and some cancers.

D-Dimer Normal D-dimer is used to help rule out clotting as the cause for the symptoms. (sensitive, not specific) D-dimer is recommended as an adjunct test. It should not be the only test used to diagnose a disease or condition. Both increased and normal D-dimer levels may require follow-up and can lead to further testing.

D-Dimer Interferences: False neg: Anticoagulant therapy (coumadin or heparin). D-dimer concentrations may rise in the elderly, and false positives may be seen with high levels of rheumatoid factor. Elevated triglycerides, lipemia, bilirubin and hemolysis can also cause false positives.

Bronchoscopy Visualize airways Obtain specimens: biopsy, bronchial lavage, brushing Cytology: study of cells Tissue to pathology

Breath Sounds _query=auscultation+breath+sounds&s earch_type=&aq=f (Listen) _query=auscultation+breath+sounds&s earch_type=&aq=f P01.HTM (Descriptions) P01.HTM m (not the best, but heart sounds also) m