pleural disease Flashcards
pleural effusion
-5–15 mL of fluid is normal in pleural space
-Pleural effusion:
-Abnormal accumulation of fluid in the pleural space
pleural pn: 4 pathophysiologic processes
-1. Transudates:
-Increased fluid in the setting of NORMAL capillaries due to INCREASED hydrostatic or DECREASED oncotic pressures
-fluid overload
-2. Exudates:
-Increased fluid due to ABNORMAL capillary permeability
-DECREASED lymphatic clearance of fluid from pleural space
-Empyema: INFECTION in pleural space, pus
-Hemothorax: BLEEDING into pleural space
transudate causes
-CHF (>90%) -> bilateral*
-Cirrhosis w/ascites- low protein
-Nephrotic Syndrome- low protein
-Peritoneal Dialysis
-Acute atelectasis
-Constrictive pericarditis
-PE
-Superior vena cava obs
exudate causes
-infection or cancer
-Pn*
-Ca*
-PE
-Bacterial, viral, fungal, parasitic
-Post MI
-Chronic atelectasis
-Asbestos
-Sarcoid-rare
signs and symptoms
-Dyspnea, cough, or chest pain- Small less symptomatic
-Physical findings:
-Small: none
-Larger: dullness to percussion, diminished or absent breath sounds over effusion, increase tactile fremitus
-Massive: may have contralateral shift of trachea and bulging of the intercostal spaces
labs
-Diagnostic Thoracentesis: gold standard
-Indications: new pleural effusion and no clinically apparent cause
-1. Visualization of fluid
-2. Send to lab:
-Cell count and cell differential, pH, protein, LDH, glucose -> determines Transudate vs exudate
-Additional tests in selected patients: amylase, cholesterol, triglycerides, N-terminal pro-brain natriuretic peptide (NT-proBNP), creatinine, adenosine deaminase (ADA), gram and acid-fast bacillus (AFB) stain, bacterial and AFB culture, and cytology
pleural fluid analysis
hemorrhagic
mixture of blood and pleural fluid
10,000 rbc/ml to create blood-tinged fluid (dont need to know numbers)
-blood tinged
hemothorax
-gross blood in pleural space
-100,000 rbc /ml create grossly bloody pleural fluid
-Defined as a ratio of pleural fluid hematocrit to peripheral blood hematocrit > 0.5
-gross appearance:
-straw colored
-blood stained
-purulent
-chylous
exudate lights criteria rule***
-Effusion that has ONE OR MORE of the following is exudate:
-Pleural fluid protein/serum protein ratio > 0.5, or
-Pleural fluid LDH/serum LDH ratio > 0.6, or
-Pleural fluid LDH greater than two-thirds the upper limits of the laboratory’s normal serum LDH
transudates
-Transudates have NONE of mentioned exudate features/criteria
-Occur in setting of normal capillary integrity and suggest ABSENCE of local pleural disease
-Distinguishing laboratory findings include:
-Glucose=serum glucose -> normal (low in exudate bc its using the energy)
-pH between 7.40 -7.55 (nl 7.6)
-< 1,000 wbc/mcL with a predominance of mononuclear cells
other features of pleural fluid
-Pleural fluid pH is useful in the assessment of parapneumonic effusions
-A pH below 7.30 -> drain
-Elevated pleural amylase:
-Pancreatitis, pancreatic pseudocyst
-Adenocarcinoma of pancreas
-Esophageal rupture
-Cytology
imaging
-Standard upright CXR:
-75–200 mL to be visible in costophrenic angle
-May become loculated by pleural adhesions:
-Round/oval fluid collections in fissures resembling intraparenchymal masses (pseudotumors)
-Chest CT scans: May identify as little as 15 mL of fluid
transudative treatment
-Transudative pleural effusions:
-Treat underlying condition - will just fill again if not
-Therapeutic thoracentesis for significant dyspnea
-Often transient effect:
-Repeat again and reassess dx
-Refractory:
-Pleurodesis- irritant into the space- obliterates the space so no fluid can fill
-Indwelling pleural catheter- drain at home
exudate treatment
-Malignant Pleural Effusion:
-Most common: lung and breast cancer
-Variety of Mechanisms
-Local treatment:
-Drainage: repeated thoracentesis or chest tube
-Long-term if needed:
-Pleurodesis
-Indwelling pleural catheter (eg, Pleurex) for home drainage
