• Know when to consider a thoracentesis
• Know how to evaluate if safe to perform thoracentesis
• Know when to consult specialists
• Quick review of pathophysiology of effusions
• Know how to analyze the fluid obtained
• Know when pleural fluid results suggest a need for a chest tube
• Summary

• Dyspnea
• Unstable pulmonary mechanics, gas exchange
• When the cause of the effusion is unclear

• Normal hemostasis
• Effusions with thickness > 1 cm on lateral decubitus film
• Ultrasound evaluation of the pleural space
• Weigh risks and benefits of procedure
• 4 studies between 1983 and 1994 looking at complications of thoracentesis reported rates of pneumothorax between
11 to 19%.
• 2 studies in 2009 and 2010 specifically addressing use of ultrasound for fluid location show risk of pneumothorax declines to 0.6 to 1.1%. Good training and experience matter.
• Risks for complications: large volume thoracentesis, COPD

• Consult Pulmonary Team when:
• If overall clinical situation warrants pulmonary specialty assist
• If pre-procedure evaluation indicates may be difficult thoracentesis to perform
• If medical team lacking a member who feels confident performing the procedure
• Pulmonary team strongly encourages consults with them prior to requesting Intervention
Radiology to perform the procedure

Pleural fluid accumulates when formation exceeds absorption
Normally:
Fluid enters pleural space from parietal pleura capillaries and is drained via the lymphatics in parietal pleura.
Fluid can also come from: interstitial spaces of lung via visceral pleura peritoneal cavity via small holes in diaphragm.

• Transudative effusions occur with either increased mean capillary pressure or decreased oncotic pressure
• Cirrhosis Left ventricular failure Nephrotic syndrome
• SVC obstruction Myxedema Peritoneal dialysis PE
• Exudative effusions occur with damage or disruption of the normal pleural membranes or vasculature occurs, leading to increased capillary permeability or decreased lymphatic drainage.
• Infectious diseases
• Malignancy
• Pulmonary embolism
• Collagen vascular diseases: RA, SLE, Wegener’s g.,Sjogren’s
• Drug-induced: nitrofurantoin, amiodarone, bromocriptine

Differentiation between exudative and transudative
Exudative effusions meet at least one of the following criteria, transudative meet none:
Light’s criteria:
• Pleural fluid protein/serum protein>0.5
• Pleural fluid LDH/serum LDH>0.6
• Pleural fluid LDH more than 2/3 normal upper limit for serum
2 Test Rule:
• Pleural fluid cholesterol > 45 mg/dL
• Pleural fluid LDH > .45 upper limit normal serum LDH
3 Test Rule: as above 2 Test, but add:
• Pleural fluid protein > 2.9 g/dL
– Note if fluid exudative, need description of fluid, pH, glucose level, differential cell count, microbiologic studies, and cytology

• Glucose < 60 mg/dL
• Malignancy
• Bacterial infections
• Rheumatoid pleuritis
• Amylase
• Acute pancreatitis
• Esophageal rupture
• Lung carcinoma
• Triglycerides > 110 mg/dL, milky appearance
• Chylothorax , usually from trauma or mediastinal tumors
• Cell count predominantly neutrophils in febrile pt with normal pulmonary parenchyma
• Intraabdominal abscess

• Bloody pleural fluid
• Pleural hematocrit/serum hematocrit > 0.5 = hemothorax
» Usually result of trauma or tumor, or infarction
• Tuberculous effusions
• Exudative with predominantly small lymphocytes
• Adenosine deaminase > 40 IU/L
• Interferon gamma > 140 pg/mL, positive PCR for TB DNA
• Fluid culture, needle biopsy of pleura
• pH < 7.3
• Empyema malignancy esophageal rupture
• Collagen vascular disease TB

(placed in increasing order of importance)
• Loculated pleural fluid
• Pleural fluid pH < 7.20
• Pleural fluid glucose < 60 mg/dL
• Chylothorax
• Hemothorax
• Positive Gram stain or culture of pleural fluid
• Presence of gross pus in pleural space

• Indications: symptom relief, stabilization, and diagnostic
• Weigh risks and benefits
• Pre-procedure, double check safety: hemostasis, fluid quantity and location
• Call Pulmonary consult if:
• Need pulmonary input in the case
• Pre-procedure check indicates a difficult thoracentesis
• Team lacking a member with good experience and confidence in performing the thoracentesis
• Recommend calling Pulmonary prior Interventional
Radiology

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Gordon CE, Feller-Kopman D, Balk EM,
Arch Intern Med. 2010;170(4):332
Smetana GW
3.
Complications associated with thoracentesis.
Seneff MG, Corwin RW, Gold LH
Chest 1986; 90:97-100
4.
Thoracentesis: complicatons, patient experience and diagnostic value.
Collins TR, Sahn SA.
Am Review Respiratory Disease 1983; 127:A114
5.
Harrison’s Principles of Internal Medicine, 17 th edition.
Fauci, Braunwald, Kasper, Hauser, Longo, Jameson, Loscalzo.
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UpToDate online. www.uptodate.com.