Week 2 - Pleural Disease and chest tubes

Question 1

What is Light’s criteria?

Answer 1

Diagnostic criteria for EXudative pleural effusions:
Total protein ratio >0.5 (fluid:serum)
LDH ratio >0.6 (fluid:serum)
LDH fluid level >2/3 ULN

Question 2

What instances is Light’s Criteria inaccurate?

Answer 2

Pt’s who are on diuretics, add a fluid albumin level to assess for albumin gradient less than or equal to 1.2 is c/w exudate

Question 3

What are the most common causes of pleural effusions?

Answer 3

Cardiac failure, pneumonia (e.g. parapneumonic), malignancy

Question 4

What past medical hx suggests a transudative pleural effusion?

Answer 4

Cardiac hx/HF, renal insufficiency, liver disease, hypoalbuminemia – supported if there are bilateral effusions

Question 5

What is the DDx for pt who presents with trauma and new pleural effusion?

Answer 5

Hemothorax, chylothorax

Question 6

What are indications for urgent thoracentesis?

Answer 6

Fever and pleurisy r/o empyema
Trauma or on anticoagulation r/o hemothorax
Effusions not responsive to diuresis

Question 7

Pleural fluid appearance: milky white

Answer 7

chylothorax

Question 8

Pleural fluid appearance: bloody

Answer 8

hemothorax

Question 9

What is the diagnostic criteria of hemothorax?

Answer 9

Hct ratio 0.5 or greater (fluid:peripheral)

Question 10

Pleural fluid appearance: putrid/turbid

Answer 10

empyema, supported by pH <7.20

Question 11

Pleural fluid appearance: black

Answer 11

aspergillus infection

Question 12

Pleural fluid appearance: food particles

Answer 12

esophageal rupture

Question 13

Pleural fluid cell count differential: lymphocyte predominant

Answer 13

malignant, TB, chylothorax, RA, sarcoidosis

Question 14

Pleural fluid cell count differential: neutrophil predominant

Answer 14

PE, parapneumonic, acute TB, benign effusion 2/2 asbestos exposure

Question 15

Pleural fluid cell count differential: eosinophil predominant

Answer 15

unclear significance, up to 1/3 of these effusions goes undiagnosed

Question 16

What percentage of malignant pleural effusions have negative cytology on initial diagnostic tap?

Answer 16

40%

Question 17

If pleural effusion 2/2 to tuberculosis is suspected, what lab should you send off the pleural fluid?

Answer 17

Adenosine deaminase (can be normal in HIV+ pts with TB)

Question 18

What is the next step for pleural effusions of unclear etiology and fluid analysis has not been helpful?

Answer 18

Pleural biopsy

Question 19

When is bronchoscopy indicated to eval pleural effusions?

Answer 19

Typically it is not indicated unless pt with hemoptysis or suspected malignant neoplasm on chest imaging

Question 20

What are indications for chest tube over thoracentesis?

Answer 20

1) PTX
2) hemothorax, chest trauma
3) empyema/parapneumonic effusions
4) large pleural effusions
5) coagulopathy/increased risk of bleeding
6) bronchopleural fistula

Question 21

What are the common complications of thoracentesis?

Answer 21

1) PTX, rare and seldom requires subsequent chest tube
2) infection
3) bleeding
4) pleurisy
5) re-expansion pulmonary edema

Question 22

How is re-expansion pulmonary edema avoided?

Answer 22

Limit total amount of pleural fluid removed to 1.5L

Question 23

What are contraindications to thoracentesis?

Answer 23

1) coagulopathy

2) infection of overlying skin at point of incision

Question 24

What are the benefits of tPA-dornase therapy for empyema compared to single agent alone?

Answer 24

1) increased pleural fluid output
2) decreased hospital stays
3) lower requirement of surgical referrals

Question 25

What was the dose, frequency, and duration of intrapleural fibrinolysis therapy in MIST2 that demonstrated improved outcomes for empyema?

Answer 25

tPA 10mg and dornase 5mg BID x 3 days

Question 26

A normal pleural space is filled with how much pleural fluid

Answer 26

7-14mL of low-protein fluid to lubricate the lining of the lungs

Question 27

What aspects of fluid sampling falsely raises pleural fluid pH?

Answer 27

Air in syringe, prolonged time prior to processing, presence of lidocaine

Question 28

What is trapped lung?

Answer 28

Fibrous visceral pleural thickening that prevents lung re-expansion, thoracentesis alone will not relieve sxs