Use of Human Serum Albumin in Critically Ill Patients: A Narrative Review

<b>Background</b>: Human serum albumin (HSA), the most abundant plasma protein, is essential for oncotic pressure, endothelial protection, drug binding, and immune modulation. Despite its widespread clinical use since the 1940s, its therapeutic benefit in critically ill patients remains debated. This narrative review summarizes current evidence on HSA use in common intensive care scenarios. <b>Clinical Applications</b>: In hepatorenal syndrome (HRS), albumin combined with vasoconstrictors like terlipressin improves renal function and survival. In spontaneous bacterial peritonitis (SBP), albumin lowers the risk of acute kidney injury and mortality, particularly in high-risk cirrhotic patients. Post-paracentesis albumin reduces circulatory dysfunction and may enhance survival in cirrhosis. For septic shock, trials show no overall mortality benefit over crystalloids, though albumin may offer hemodynamic advantages in specific subgroups. In acute respiratory distress syndrome (ARDS), albumin improves oxygenation in hypoalbuminemic patients, without survival benefits. During major cardiac or abdominal surgery, albumin reduces fluid needs and postoperative complications, especially in hypoalbuminemic individuals. In acute brain injury, albumin's role is controversial: it may aid recovery after cerebral hemorrhage, but can worsen outcomes in traumatic brain injury. In trauma and ECMO patients, albumin may stabilize hemodynamics and improve outcomes in selected cases. <b>Conclusions</b>: Inappropriate albumin use remains common, and evidence on its optimal concentration, dose, timing, and patient selection is limited. HSA is safe and beneficial in specific situations. Routine use should follow evidence-based guidelines. Future research must identify patients who are most likely to benefit and clarify optimal dosing strategies, concentrations, and therapeutic goals.