What is the proper procedure and management for ascites tapping?

Ascites Tapping: Comprehensive Procedural and Management Guide

Indications for Diagnostic Paracentesis

All cirrhotic patients with ascites require diagnostic paracentesis on hospital admission and whenever signs of infection, encephalopathy, renal impairment, or peripheral leukocytosis develop without clear precipitant. 1, 2

• New-onset ascites mandates immediate diagnostic tap to establish etiology and rule out spontaneous bacterial peritonitis (SBP), which carries 15% prevalence on admission and high mortality if untreated 1, 2
• Informed consent should be obtained before any paracentesis procedure 1

Procedural Technique

Site Selection and Needle Insertion

• Insert needle in the left lower abdominal quadrant (preferred) or right lower quadrant, approximately 15 cm lateral to the umbilicus, at least 8 cm from midline and 5 cm above symphysis pubis where ascites depth is greatest 1, 3
• Use the "Z-track" technique with a cannula containing multiple side perforations to prevent blockage by bowel wall 3
• Avoid the inferior and superior epigastric arteries that run lateral to the umbilicus toward the mid-inguinal point 1
• Ultrasound guidance should be used when available to reduce adverse events 1, 3

Coagulopathy Management

Paracentesis is NOT contraindicated in patients with abnormal coagulation profiles, and routine correction of INR or platelet count is not recommended. 1, 3

• Proceed safely even with INR up to 8.7 or platelets as low as 19×10³/μL 3
• Most patients with cirrhotic ascites have prolonged PT and thrombocytopenia; fresh frozen plasma is not routinely indicated 1
• Consider pooled platelets only if platelet count <40,000/mm³ 1
• Complications (abdominal hematomas) occur in <1% of patients; serious complications like hemoperitoneum or bowel perforation are rare (<1/1000) 1

Diagnostic Fluid Analysis

Essential Tests

• Ascitic fluid neutrophil count and culture: Inoculate at least 10 mL into aerobic and anaerobic blood culture bottles at the bedside before antibiotics 1, 2
• Serum-ascites albumin gradient (SAAG): SAAG ≥1.1 g/dL indicates portal hypertension with 97% accuracy; SAAG <1.1 g/dL suggests non-portal hypertension causes (malignancy, tuberculosis, nephrotic syndrome) 1, 2
• Ascitic amylase: Measure when clinical suspicion of pancreatic disease exists 1
• Cytology: Request when underlying malignancy is suspected 1

Interpretation of Neutrophil Count

• Neutrophil count >250 cells/mm³ is diagnostic of SBP and requires immediate empiric antibiotic therapy with third-generation cephalosporins (cefotaxime 2g IV every 12 hours) before culture results 1, 2
• Bloody ascitic fluid (red blood cells usually <1,000 cells/mm³ in cirrhotic ascites) occurs in ~2% of cirrhotics, with hepatocellular carcinoma underlying ~30% of cases 1

Therapeutic Large-Volume Paracentesis (LVP)

Volume Guidelines and Drainage Rate

Complete drainage of ascites in a single session is recommended without specifying an upper limit, as rapid removal is safe and more effective than serial smaller procedures. 1, 3

• Drain ascites to dryness as rapidly as possible over 1-4 hours at approximately 2-9 liters per hour 3
• Historical concerns about circulatory collapse from rapid drainage are disproven; removing >10 liters over 2-4 hours causes only minimal blood pressure changes (<8 mmHg decrease) 3
• Do not artificially slow drainage rate—this outdated practice delays symptom relief without evidence-based benefit 3
• The drain should not be left in overnight 3

Albumin Replacement Protocol

For paracentesis >5 liters, albumin replacement is mandatory at 8 g per liter of ascites removed (e.g., 100 mL of 20% albumin per 3 liters of ascites). 1, 3

• Infuse albumin after paracentesis is completed, not during the procedure, using 20% or 25% albumin solution 3
• For volumes <5 liters, albumin replacement is not necessary unless the patient has acute-on-chronic liver failure or high risk of post-paracentesis acute kidney injury 3
• Albumin prevents post-paracentesis circulatory dysfunction (PICD), reducing odds of PICD by 61%, hyponatremia by 42%, and mortality by 36% compared to alternative volume expanders 3
• Alternative synthetic plasma expanders (150-200 mL of gelofusine or haemaccel) can be used for <5 liter paracentesis 1

Post-Procedure Care

• After completion, have patient lie on opposite side for 2 hours if there is leakage of remaining ascitic fluid 3
• Gentle mobilization of the cannula or turning the patient onto their side may assist complete drainage 3

Medical Management of Ascites

Dietary Sodium Restriction

• Restrict dietary salt to 88-90 mmol/day (approximately 5-5.2 g salt/day or 2000 mg sodium/day), essentially a "no added salt" diet 1, 2
• Patients should read labels on prepared foods to confirm daily salt intake is within limits 1
• Dietary salt restriction alone creates negative sodium balance in 10% of patients 1
• Bed rest is not recommended for treatment of ascites due to risk of muscle atrophy and prolonged hospitalization 1

Diuretic Therapy

First-line treatment is spironolactone alone, starting at 100 mg/day and increasing to 400 mg/day if needed. 1

• If spironolactone alone fails, add furosemide up to 160 mg/day, maintaining a spironolactone:furosemide ratio of 100:40 mg to preserve normal potassium levels 1, 2
• Monitor biochemistry and clinical status carefully during diuretic escalation 1
• Diuretics can cause dehydration, confusion, electrolyte abnormalities, and renal impairment requiring close monitoring 1

Management of Hyponatremia During Diuretic Therapy

Serum sodium 126-135 mmol/l with normal creatinine: Continue diuretic therapy but observe electrolytes closely; do not water restrict 1

Serum sodium 121-125 mmol/l with normal creatinine: International opinion supports continuing diuretics, but a more cautious approach is to stop diuretics and observe the patient 1

Serum sodium 121-125 mmol/l with elevated creatinine (>150 mmol/l or >120 mmol/l and rising): Stop diuretics immediately and give volume expansion with colloid (haemaccel, gelofusine, voluven) or saline 1

**Serum sodium <120 mmol/l**: Stop diuretics; most patients should undergo volume expansion with colloid or saline, but avoid increasing serum sodium by >12 mmol/l per 24 hours to prevent central pontine myelinolysis 1, 2

• Water restriction should be reserved only for clinically euvolemic patients with severe hyponatremia who are not taking diuretics and have normal creatinine 1
• Chronic hyponatremia in cirrhotic ascites is seldom morbid, and rapid correction with hypertonic saline causes more complications than the hyponatremia itself 2

Refractory Ascites Management

Definition and Treatment Options

Refractory ascites is defined as ascites unresponsive to maximum diuretic doses (spironolactone 400 mg/day plus furosemide 160 mg/day) with sodium restriction, or ascites that recurs rapidly after therapeutic paracentesis. 2

• Occurs in approximately 10% of patients with cirrhotic ascites 4
• First-line treatment is repeated large-volume paracentesis with albumin replacement 1, 2
• Transjugular intrahepatic portosystemic shunt (TIPS) should be considered for carefully selected patients requiring frequent therapeutic paracentesis, with appropriate risk-benefit assessment 1
• TIPS improves renal function, sodium excretion, and quality of life but without proven survival benefits 5
• Patients with more advanced liver disease may be harmed by TIPS placement 1

Liver Transplantation Considerations

Development of ascites is an important indication for liver transplantation evaluation, as it marks hepatic decompensation and significantly worsens prognosis. 1

• Patients with cirrhotic ascites have 85% survival at 1 year and 56% at 5 years without transplantation 4
• All patients with spontaneous bacterial peritonitis should be considered for transplantation referral 1
• Liver transplantation is the ultimate curative treatment for ascites and its complications 1
• Treatment of ascites improves quality of life and prevents complications like SBP but does not significantly improve survival without transplantation 1, 6

Critical Pitfalls to Avoid

• Never delay diagnostic paracentesis due to coagulopathy concerns—SBP carries high mortality and must be diagnosed promptly 1, 2
• Never perform serial paracenteses without initiating diuretic therapy in diuretic-sensitive patients, as this fails to address underlying sodium retention 2
• Never restrict fluids routinely in patients with chronic hyponatremia, as this may worsen effective hypovolemia and ADH secretion 1, 2
• Never correct sodium rapidly (>12 mmol/L per 24 hours) due to risk of central pontine myelinolysis, especially in transplant candidates 1, 2
• Never withhold albumin for large-volume paracentesis >5 liters, as PICD occurs in up to 80% without volume expansion versus 18.5% with albumin 3