Pleural effusions Flashcards
Uncomplicated vs complicated pleural effusion etiology
uncomplicated - sterile exudate in pleural space - movement of fluid from lung parenchyma to pleural space due to increased hydrostatic pressure. It will resolve after PNA resolves
Complicated - bacterial invasion of pleural space. This causes lowering of pleural fluid glucose and increased LDH (lysis from neutrophils)
pleural fluid analysis of uncomplicated parapneumonic effusions
sterile exudate in pleural space
pH >7.2
WBC <50K
glucose >60
no bacteria on gram stain or culture
Treatment of parapneumonic effusion that is uncomplicated
antibiotics
Treatment of complicated parapneumonic effusions
antibiotics and drainage.
Lab values for complicated parapneumonic effusion
bacterial invasion of pleural space
pH<7.2
glucose <60
WBC>50K
treat with antibiotics + drainage
often do you see malignant cells on effusions
60% but need 3 separate thoracenteses to detect up to 90% of malignant effusions.
If concerned about cancer and first thoracentesis is unrevealing repeat thoracentesis.
if 3 negative thoracentesis then needs thorascopy performed
causes of chylothorax?
post intrathoracic surgery, cancer evasion
Spontaneous cases or idiopathic cases are about 10% of all presentations.
Disruption of thoracic duct as it crosses mediastinum at level of 5th intercostal space
Lab findings on pleural studies that indicate chylothorax?
white or milky and lipophilic looking
around 900-1000 TG
WBC mildly elevated with lymphocytic predominance
mean pH 7.4
can be exudative or transudative.
Light’s criteria
total protein pleural / serum >0.5
LDH pleural / serum: >.6
LDH >2/3 upper limit of normal serum value
When do we care about pleural cholesterol?
pleural cholesterol >45 plays a role in a 2 and 3-test rules to diagnose exudative pleural effusions based on pleural fluid LDH and total protein.
Not a definitive criteria.
How do we treat chylothorax?
address the underlying cause, pleural drainage, low fat diet, thoracic duct ligation and thoracic duct embolization or pleurodesis.
What is Empyema
It’s a complicated parapneumonic effusion with positive gram stain, acid pH and purulent fluid. clinical diagnosis based on physical appearance of pleural fluid in the setting of lung infection -positive Gram stain and WBC with neutrophilic predominance -PH<7.2 and low glucose and normal or mildly elevated triglyceride level
Malignant effusion lab work on pleural studies
generally have positive cytology in 60-90% of cases exudative generally.
exudative pleural effusions are driven by
inflammation
transudate pleural effusions are driven by
hydrostatic or oncotic pressure
common causes of exudative pleural effusions
infection (TB or pneumonia)
malignancy
connective tissue disease
pulmonary embolism
pancreatitis
post CABG
common causes of transudate pleural effusions
cirrhosis (hepatic hydrothorax)
nephrotic syndrome
heart failure
constrictive pericarditis
peritoneal dilaysis
low pH very low glucose levels (<30 mg/dl) extremely high LDH levels >1000
seen in rheumatoid pleurisy or Rheumatoid effusions - they are yellow green in color see cell counts <5000 and have high lymphocytes
hypothyroidism pleural effusions
can be both transudative or exudative.
pulmonary HTN pleural effusion
tend to be transudative
what is benign asbestos related pleural effusion?
early pleural effusion manifestation of asbestos related lung dx that occurs 10-15 years after exposure. this predates asbestos-related pleural plaques and may be marker of future development of diffuse pleural thickening
Benign asbestos related pleural effusion characteristics
small <500 ml, bloody, exudative, eosinophilic predominance >10% nucleated cells >50%
symptoms of benign asbestos related pleural effusion
see dyspnea, low grade fever, pleuritic chest pain and
what happens to benign asbestos related pleural effusion?
spontaneous resolution over weeks to months is normal.
malignant pleural effusions
see lower glucose exudative and generally lympohcytic but can have eosinophils in it.
eosinophilic effusion
asbestosis, dantrolene, bromocriptine, nitrofurantoin and valproic acid.
RA effusions
low glucose and low pH
see large exudative pleural effusions.
mimics malignant or Tb pleural fluid studies.
TB effusion
exudative, low pH and low glucose
needs to live in edemic area see predominantly lymphocytic effusion.
what causes chylothorax?
TG>110 supports diagnosis seen in non traumatic and traumatic causes look for bulky adenopathy b’c lymphoma is a cause of chylothorax
what are traumatic causes of thoracic duct injury?
CVC placement via the subclavian approach and esophageal surgery
if chylothorax is associated with cirrhosis or CHF or nephritic syndrome
chylothorax can be transudative
what are non traumatic causes of thoracic duct injury?
Non traumatic: thoracic duct obstruction from malignancy, sarcoidosis or retrosternal goiter and infections like TB of filariasis
amylase levels are high in pleural effusions when
it’s related to esophageal rupture or pancreatitis
cholesterol effusions are seen with
TB or rheumatoid pleurisy
seen with exudative effusions that remain in pleural space chronically so it becomes enriched with cholesterol.
TB should be suspected if pleural effusion is:
lymphocytic effusions
get acid fast staining and culture
indications for thoracentesis for a patient who has PNEUMONIA and has pleural effusion:
-free flowing and large -layers >10 mm on lateral decubitus film -demonstrates loculation -seen with thickened parietal pleura on contrast CT -clearly delineated by U/S
in treatment of empyema what needs to be done?
multiple loculated collections may need multiple test tubes chest CT needs to be done within 24 hrs to make sure chest tube location is correct and assess drainage. Needs to get both chest tube drainage and antibiotics
approach to a parapneumonic effusion
parapneumonic effusions can occur in the adjacent pleural space in the 40% of bacterial pneumonias
most parapneumonic effusions are minimal and resolve with antibiotics and effusions that are free flowing <10 mm on lateral decubitus film shoudl be observed in serial imaging alone as they are most likely to resolve with antibiotics.
loculations, pleural thickening, and large >1/2 hemithorax effusions are considered high risk features ars they are associated with higher rate of adverse effects.
diagnostic thoracentesis is needed for effusions that
are >10 mm with no high risk features on imaging
gram stain, negative culture and pH>7.2 and glucose>60 on fluid analysis shows that this is uncomplicated.
what to do for pleural effusion to be result of suspected CHF but has an exudative effusion?
calculate the serum-effusion protein difference OR serum effusion albumin gradient
if serum-effusion protein difference is >3.1 g/dl
OR
serum effusion albumin gradient >1.2 g/dl
then likely a true transudative effusion.
light criteria is 100% sensitive but only 83% specific for identifying exudates and so can have decreased specificity with diuretic use. up to 20% of pts with CHF can have exudative effusion.
