What is the recommended intravenous albumin 20% (human serum albumin) dosing regimen for an adult cirrhotic patient with ascites diagnosed with spontaneous bacterial peritonitis?

Albumin Dosing for Spontaneous Bacterial Peritonitis in Cirrhotic Patients with Ascites

For an adult cirrhotic patient with ascites and spontaneous bacterial peritonitis, administer 1.5 g/kg of 20% albumin within 6 hours of diagnosis, followed by 1.0 g/kg on day 3. 1, 2

Standard Dosing Protocol

• Day 1 (within 6 hours of SBP diagnosis): 1.5 g/kg body weight of albumin 1, 2
• Day 3: 1.0 g/kg body weight of albumin 1, 2
• Use estimated dry weight for calculation, though this can be challenging in cirrhotic patients with fluid overload 1

Practical Dosing Example

For a 70 kg patient:

• Day 1: 105 g albumin = 525 mL of 20% albumin solution
• Day 3: 70 g albumin = 350 mL of 20% albumin solution

Evidence Supporting This Regimen

• Albumin reduces renal impairment by 72% (pooled RR 0.28,95% CI 0.16-0.50) in patients with SBP 1
• Mortality decreases by 47% (pooled RR 0.53,95% CI 0.36-0.79) when albumin is added to antibiotics 1
• Renal dysfunction develops in up to 30% of SBP patients without albumin and is the strongest predictor of mortality 1

Modified Dosing for Patients with Renal Impairment

• If serum creatinine is elevated or rising: Use the full weight-based regimen (1.5 g/kg on day 1, then 1.0 g/kg on day 3) 1
• If creatinine is normal and stable: Some evidence suggests lower doses may be effective, though this remains controversial 1
• One retrospective study (N=88) found doses exceeding 87.5 g (>4×100 mL of 20% albumin) were associated with worse outcomes, possibly from fluid overload 1

Critical Distinction: SBP vs Large-Volume Paracentesis Dosing

This weight-based SBP regimen differs fundamentally from paracentesis dosing:

Indication	Dosing Method	Typical Dose
SBP	Weight-based	1.5 g/kg day 1, then 1.0 g/kg day 3 [1,2]
Large-volume paracentesis (>5L)	Volume-based	8 g per liter of ascites removed [1,3,2]

Administration Guidelines

• Infuse albumin after antibiotic administration has begun 1, 4
• Administer over 1-2 hours to minimize risk of volume overload 3
• Use 20% or 25% hyperoncotic albumin solutions; 5% albumin is inadequate 3

Mechanism of Benefit

• Albumin reduces plasma and ascitic fluid levels of TNF-alpha and IL-6 4
• Prevents elevation of nitric oxide products that occur with antibiotics alone 4
• Reduces endotoxin levels in ascitic fluid 4
• Prevents post-infection circulatory dysfunction and hepatorenal syndrome 1, 5

Common Pitfalls to Avoid

• Do not use volume-based dosing (8 g/L) for SBP—this is only for paracentesis 1, 3
• Do not delay albumin beyond 6 hours on day 1—early administration is critical 1, 2
• Do not omit the day 3 dose—both doses are necessary for optimal outcomes 1, 2
• Monitor for fluid overload, especially in patients with cirrhotic cardiomyopathy or baseline renal dysfunction 1

Concurrent Antibiotic Therapy

• Third-generation cephalosporins remain first-line antibiotics for SBP 5, 6
• Albumin is complementary to, not a replacement for, appropriate antibiotic therapy 5
• Selection of empirical antibiotics should consider local resistance patterns and whether infection is community- or hospital-acquired 5

Monitoring During Treatment

• Daily serum creatinine to detect acute kidney injury 1
• Daily serum sodium to identify hyponatremia 1
• Repeat diagnostic paracentesis at 48 hours if clinical response is inadequate 5