Pleural effusion usually occurs in presence of ascites (although ascites may detectable only by U/S)
Incidence of effusion in presence of ascites: 6% of cases
Etiology
Percutaneous Transhepatic Procedures
Increased hepatic hydrothorax may occur in rare cases after transhepatic procedures: probably occurs due to inadvertent iatrogenic defect created in diaphragm -> leakage of ascitic fluid across diaphragm
Implicated Procedures
Post-Percutaneous Transhepatic Coronary Vein Occlusion: used to control bleeding esophageal varices/transdiaphragmatic, transhepatic injection of gelfoam into coronary vein (material lodges in esophageal veins)
Percutanous Transhepatic Cholangiogram: in addition to inducing hepatic hydrothorax, this procedure can also inadvertently result in cholethorax (see Pleural Effusion-Cholethorax)
Physiology
Transudation of ascitic fluid from peritoneal space across diaphragmatic defects into pleural space
India ink injection into ascitic fluid -> appears in pleural fluid
IV injection of radiolabelled albumin: appears in ascites first, only subsequently in the pleural fluid (injection of air in peritoneal space had same results, with PTX observed, due to observable defects in diaphragm at thoracoscopy)
Pleural pressure in cirrhosis-associated effusions are higher than in other transudates (due to fluid flowing down pressure gradient into pleural space from ascites)
Decreased plasma oncotic pressure only a secondary etiologic factor in cirrhotic effusions
Diagnosis
Pleural Fluid
-Appearance: usually straw-colored but may be bloody in rare cases
pH:
LDH ratio:
Total protein ratio: pleural fluid protein is usually higher than ascitic fluid protein (but is still usually <3 g/dL)
Cell count/ diff ( may be PMN or lymphocyte-predominant): PMN count >500/mm3 strongly suggests spontaneous bacterial empyema from associated SBP
Gram stain/ culture:
Cholesterol:
Amylase: normal
CXR/Chest CT Patterns
Pleural effusion: may be large (occupying hemithorax): 67% are right-sided/ 16% are left-sided/ 16% are bilateral
Clinical
Symptoms/signs:
Signs of cirrhosis: usually dominate the clinical picture
Signs of pleural effusion (see Pleural Effusion-Transudate): dyspnea/ dullness to percussion/ decreased BS over area
Spontaneous Bacterial Pleuritis
May occur
Most, but not all, cases have associated SBP
Usually due to E.Coli
Chest tube does not appear to be necessary
Treatment
Treat Ascites (since effusion is simply an extension of the ascites)
Low sodium diet/ Lasix (start at 40 mg per day) + Aldactone (start at 100 mg per day)/ etc.
Therapeutic Thoracenteses
Contraindicated (fluid rapidly accumulates and protein depletion may occur)
Transhepatic Portosystemic Shunt (TIPSS)
May be required for refractory ascites
Complications: worsened hepatic encephalopathy, CHF (due to increased venous return to rich side of heart)
Contraindications: hepatic encephalopathy
Pleurodesis: may be required in some cases with persistent symptomatic effusion despite aggressive therapy of ascites
Monitor closely after chest tube placement, since amount of ascites can rapidly decrease (causing precipitous hypovolemia): inject Doxycycline as soon as lung is rexpanded (do not need to wait until drainage decreases)
May be done with thoracoscopic talc insufflation (or thoracoscopic placement of biological glue over diaphragmatic defect + talc insufflation)
Peritoneojugular Shunt: may control ascites but will not control effusion (since the fluid will preferentially move to the lower pressure pleural space over the central veins)
Thoracotomy: with repair of diaphragm and pleural abrasion (to effect a pleurodesis)
