What is the initial workup and management for a patient presenting with ascites?

Initial Workup and Management of Ascites

All patients presenting with new-onset ascites require immediate diagnostic paracentesis with ascitic fluid analysis before initiating any treatment, even in the absence of infection signs. 1, 2, 3

Immediate Diagnostic Steps

Paracentesis Technique and Safety

• Perform diagnostic paracentesis in all patients with new-onset grade 2 or 3 ascites and all hospitalized patients with worsening ascites or any complication. 1, 2, 3
• Insert the needle 15 cm lateral to the umbilicus in the lower quadrants to avoid epigastric vessels. 2
• Do not withhold paracentesis due to coagulopathy or thrombocytopenia—serious complications occur in less than 1 in 1000 procedures. 2, 3
• Obtain informed consent before the procedure. 1

Essential Ascitic Fluid Tests (Send Immediately)

• Inoculate at least 10 mL of ascitic fluid into aerobic and anaerobic blood culture bottles at the bedside before any antibiotics are given. 1, 2
• Neutrophil count (manual or automated)—a count >250 cells/mm³ diagnoses spontaneous bacterial peritonitis (SBP) requiring immediate empiric antibiotics. 1, 2, 3
• Total protein and albumin concentration in ascitic fluid. 1
• Simultaneous serum albumin to calculate the serum-ascites albumin gradient (SAAG). 1, 2, 3

Critical Calculation: SAAG

• Calculate SAAG by subtracting ascitic fluid albumin from serum albumin (both drawn same day). 1, 2, 3
• SAAG ≥1.1 g/dL indicates portal hypertension with 97% accuracy. 1, 2, 3
• SAAG <1.1 g/dL suggests non-portal hypertensive causes (malignancy, tuberculosis, pancreatic ascites). 1

Additional Ascitic Fluid Tests (Based on Clinical Suspicion)

• Cytology if malignancy is suspected. 1
• Amylase if pancreatic disease is suspected (typically >1000 IU/L or >6 times serum amylase in pancreatic ascites). 1
• Adenosine deaminase if tuberculosis is suspected (levels <40 IU/mL exclude TB with high accuracy). 1
• BNP if cardiac ascites is suspected. 1
• Ascitic total protein <1.5 g/dL identifies patients at higher risk for developing SBP. 1

Baseline Laboratory Assessment

Serum Tests

• Liver function tests: AST, ALT, bilirubin, alkaline phosphatase, albumin. 1, 3
• Renal function: creatinine, BUN, serum electrolytes (sodium and potassium). 1, 3
• Prothrombin time/INR and complete blood count. 3
• Urine sodium to assess sodium excretion. 1

Imaging

• Abdominal ultrasound to confirm ascites, assess liver morphology, evaluate for hepatocellular carcinoma, and assess portal vein patency. 1, 3

Immediate Management Based on Findings

If Neutrophil Count >250 cells/mm³ (SBP Diagnosed)

• Start empiric antibiotics immediately with third-generation cephalosporins (cefotaxime is most extensively studied). 1
• Administer albumin at 1.5 g/kg within the first 6 hours if signs of renal impairment are present to prevent hepatorenal syndrome. 1
• Consider all patients with SBP for liver transplantation referral. 1

If Large or Tense Ascites Present

• Therapeutic paracentesis is first-line treatment—remove all accessible fluid in a single session. 1, 2
• Administer albumin at 8 g per liter of ascites removed when removing >5 liters to prevent post-paracentesis circulatory dysfunction. 1, 2
• For paracentesis <5 liters, synthetic plasma expanders (150-200 mL of gelofusine or haemaccel) are sufficient and albumin is not required. 1

Dietary and Lifestyle Modifications

• Restrict dietary sodium to 2 g/day (90 mmol/day or 5.2 g salt/day) starting immediately. 1, 2
• Provide formal dietician consultation to maximize adherence while preventing malnutrition. 2
• Fluid restriction is NOT indicated unless serum sodium <125 mmol/L. 1, 2, 3
• Bed rest is not recommended for treatment of ascites. 1

Diuretic Therapy Initiation

Starting Regimen

• For patients with long-standing gross ascites, start combination therapy with spironolactone 100 mg daily plus furosemide 40 mg daily, as they respond better to combined treatment than monotherapy. 2
• For mild to moderate ascites, spironolactone alone may be initiated at 100 mg/day and increased stepwise to 400 mg/day. 1
• Never use furosemide as monotherapy—it is less effective than spironolactone in portal hypertension. 2

Dose Titration

• Increase spironolactone stepwise up to 400 mg/day, waiting at least 72 hours between increases due to its long half-life. 2
• If spironolactone alone fails, add furosemide up to 160 mg/day with careful monitoring. 1
• In patients with hepatic cirrhosis and ascites, initiate therapy in the hospital setting. 4, 5

Critical Monitoring During Diuresis

• Monitor serum potassium within 1 week of initiation or dose changes, then regularly. 2
• Check serum creatinine, electrolytes, and renal function frequently. 2
• If creatinine rises significantly or exceeds 150 μmol/L (or >120 μmol/L and rising), stop diuretics immediately. 1

Management of Hyponatremia During Treatment

• Serum sodium 126-135 mmol/L with normal creatinine: Continue diuretics but monitor electrolytes closely. Do not restrict water. 1
• Serum sodium 121-125 mmol/L with normal creatinine: Stop or reduce diuretics cautiously. 1
• Serum sodium 121-125 mmol/L with elevated creatinine: Stop diuretics and give volume expansion. 1
• Serum sodium <120 mmol/L: Stop diuretics and consider volume expansion with colloid or saline, but avoid increasing sodium by >12 mmol/L per 24 hours. 1, 2

Prognostic Considerations and Transplant Referral

Poor Prognosis Indicators

• The development of ascites reduces 5-year survival from 80% in compensated cirrhosis to 30% in decompensated cirrhosis with ascites. 1, 2, 3
• One and two-year mortality after ascites development is approximately 40% and 50%, respectively. 1

Transplant Evaluation

• Refer all patients with ascites for liver transplantation evaluation, as ascites development is an important landmark indicating hepatic decompensation. 1, 2
• Treatment of ascites improves quality of life and prevents complications like SBP, but does not significantly improve survival—only liver transplantation does. 1

Definition of Refractory Ascites

• Ascites is refractory when it cannot be mobilized or recurs early despite sodium restriction and maximum diuretics (spironolactone 400 mg/day plus furosemide 160 mg/day). 2, 6
• Refractory ascites requires repeated large-volume paracentesis or consideration of transjugular intrahepatic portosystemic shunt (TIPS). 1

Critical Pitfalls to Avoid

• Never assume alcoholic patients have alcoholic liver disease—always investigate other causes, as approximately 15% of ascites cases have non-cirrhotic causes. 1, 2
• Do not restrict fluids unless hyponatremia (sodium <125 mmol/L) is present. 1, 2, 3
• Avoid NSAIDs—they reduce diuretic efficacy, worsen renal function, and can precipitate renal failure. 2, 4
• Do not give fresh frozen plasma before paracentesis—it is not supported by evidence and coagulopathy is not a contraindication. 2
• Do not test serum CA-125—it is elevated in all patients with ascites regardless of cause and leads to unnecessary gynecologic referrals. 1
• Sudden alterations in fluid and electrolyte balance may precipitate hepatic encephalopathy and coma in cirrhotic patients—strict observation is necessary during diuresis. 4, 5