Ascites

Background

• US ~80% due to cirrhosis and associated portal hypertension
• Less common causes: peritoneal or metastatic cancer, heart failure, tuberculosis, nephrotic syndrome, Budd-Chiari, sinusoidal obstructive syndrome (S.O.S), or complications from procedures and pancreatitis

Evaluation

• Bedside ultrasound on admission to confirm presence of ascites
• Diagnostic paracentesis in all pts with ascites on admission mainly to rule out occult SBP
  • Initial paracentesis or when cause of ascites is uncertain: Total Protein, serum and BF Albumin, cell count w/diff, culture
  • Subsequent/Serial paracenteses: cell count w/diff, culture, protein
  • Always inoculate culture bottles at bedside (aerobic, then anaerobic)! Use luer-lock syringe and vacutainer, then hand deliver samples to 4^th floor lab to ensure proper/timely delivery
• There is no guideline for INR cutoff for paracentesis, although our procedure team often looks for INR < 3.5 (IR usually doesn’t care about INR)
• Serum-ascites albumin gradient (SAAG) = serum albumin - ascites albumin. SAAG ≥ 1.1 accurately predicts portal hypertension, but this may be due to either cardiac or hepatic causes which can be further evaluated with total protein in the ascites:

• Calculate PMNs from fluid: Total nucleated cells x percent neutrophils
  • If ≥> 250, diagnostic of SBP in cirrhosis
• Correction for RBCs: For every 250 RBCs in fluid, subtract 1 PMN
• Other tests:
  • • Triglycerides: if fluid is milky
    • Cytology: if very concerned for peritoneal carcinomatosis. May need up to 3 separate samples (50ml or more) to be able to detect malignant cells
    • ADA: if concern for peritoneal TB
    • Hematocrit: For bloody appearing fluid (not just serosanguinous) to rule out hemoperitoneum. There needs to be a recent serum HCT for comparison.
    • Amylase: If concerned for pancreatic ascites
    • Glucose, LDH if concern about secondary peritonitis (see below)

Management

• Cessation of alcohol, if applicable
• 2000mg sodium restriction per day for all ascites (Grade 1-3)
• Diuretics (spironolactone and typically oral furosemide)
  • Start at 100mg of spironolactone with up titration to 400mg
  • Furosemide is added if insufficient diuresis or if limited by hyperkalemia
  • Can then ↑ to a max of 400:160
  • If poor response can change to torsemide 10 and ↑ 40 mg max for cirrhotics
  • Fluid restriction usually not necessary unless serum sodium <130 mmol/L
• Large volume paracentesis should be performed for tense ascites or refractory ascites (grade 3), regardless of serum Cr. PTs should be tapped dry with each paracentesis
• 6-8g of albumin per liter of ascites removed , even if < 5L
  • • So, if 7L removed, you would give 42-56g of albumin
• Target weight loss of 0.5kg/day when diuresing to avoid renal injury
   

Refractory Ascites:

• Two distinctions:
  • Diuretic-resistant: lack of response to diuretics (max spironolactone 400mg/lasix160mg), Na restriction and rapid recurrence following paracentesis
  • Diuretic-intractable: unable to tolerate diuretic therapy 2/2 adverse drug effects (unexplained HE, AKI, K abnormalities, hypoNa, intractable muscle cramps)
• Management aside from liver transplant:
  • Discontinue of diuretics once refractory ascites has been established
  • Consider oral midodrine; can be especially helpful if pt is also hypotensive
  • Serial paracenteses, generally arranged OP with IR
  • Consider TIPS (trans jugular intrahepatic portosystemic shunt; has survival benefit)
  • Following TIPS, cessation or decrease in ascites should occur in 4-6 weeks
    •  If pt with TIPS presents to hospital with accumulation of ascites, can signal that shunt is no longer patent. Obtain RUQ w/doppler or CTA abdomen/pelvis to look for patency. May require IR study if high enough concern

• Medications to avoid or discontinue with refractory ascites:
  • ACE/ARB, NSAIDS, β Blockers (if Na <130, systolic <100, MAP <65 or AKI)

Background

• transudative effusion, typically unilateral (right sided); reflects ascitic fluid that passes through a small defect in the diaphragm
• present in 5% of cirrhosis with ascites and portends a poor prognosis

Evaluation

• Often suspected clinically, though must exclude pleural/cardiopulmonary process
• Thoracentesis will demonstrate a transudative effusion and should be evaluated with standard pleural fluid lab tests:
  • Cell count w/ diff
  • Culture (inoculated at the bedside!)
  • Protein, albumin, LDH, bilirubin
  • Other considerations: triglycerides, amylase, cytology

• Rule out SBE:
  • Diagnosed by the following criteria:
    • Positive pleural fluid culture, PMN>250
    • Negative pleural fluid culture with PMN >500
    • No evidence of pneumonia on imaging (to r/o parapneumonic effusion)
  • ½ of cases will present with concomitant SBP