Corrected post as of June 8, 2025
Written by Peter Liu
Spoon Feed
In a retrospective analysis of patients with septic shock and renal impairment, albumin administration was associated with increased risk of in-hospital death or initiation of renal replacement therapy.
Does hyperoncotic albumin increase risk of renal injury?
The extracellular fluid space is comprised of roughly 25% intravascular volume, and 75% interstitial fluid.* In low effective blood volume states like septic shock, it makes pathophysiological sense to administer colloids that remain intravascular over crystalloids that rapidly redistribute into extracellular space. Meta-analyses suggest marginally better clinical outcomes with concentrated albumin over crystalloids in sepsis. Despite this, crystalloids remain first-line, largely due to cost and emerging safety concerns with concentrated albumin.
A recent retrospective, multicenter, inverse probability-weighted cohort study of 9,988 U.S. patients with septic shock and renal impairment found early albumin use associated with increased risk of renal replacement therapy (RRT) or in-hospital mortality (OR 1.29; 95%CI 1.14–1.47; p<.001). The effect was more pronounced with 25% albumin (OR 1.43; 95%CI 1.16–1.76) than with 5% albumin (OR 1.07; 95%CI 0.84–1.34).
This echoes earlier safety concerns over hyperoncotic starches like hydroxyethyl starch, which increased mortality and renal failure via osmotic tubular injury. Hyperoncotic albumin may cause similar inflammation-mediated renal damage. Given the retrospective design and potential for residual confounding, this study introduces a hypothesis that requires an RCT to establish a causal link.
How does this change my practice?
Generally, crystalloids remain my first-line treatment for most conditions requiring fluid resuscitation. They are more readily available, cheaper, and offer equivalent efficacy compared to colloids. However, in situations of profound hypoalbuminemia, high pressor requirement, or third-spacing (e.g. fluid overload in the extracellular fluid space), I often consider high-concentration albumin administration due to pathophysiology. This retrospective study challenges that belief and makes me more cautious to use albumin.
*The May 27, 2025 post said: “Total body fluid is distributed in roughly 25% intravascular volume (blood vessels), and 75% extracellular space (tissue and interstitial).” The post has been restored to the author’s original phrasing as above.
Source
Comparative Effectiveness of Albumin vs No Albumin on Renal Replacement Therapy and Mortality in Patients With Septic Shock and Renal Impairment. Chest. 2025 Apr;167(4):1090-1098. doi: 10.1016/j.chest.2024.10.012. Epub 2024 Oct 18. PMID: 39426720
