Albumin administration in the acutely ill: what is new and where next?

Abstract

Albumin solutions have been used worldwide for the treatment of critically ill patients since they became commercially available in the 1940s. However, their use has become the subject of criticism and debate in more recent years. Importantly, all fluid solutions have potential benefits and drawbacks. Large multicenter randomized studies have provided valuable data regarding the safety of albumin solutions, and have begun to clarify which groups of patients are most likely to benefit from their use. However, many questions remain related to where exactly albumin fits within our fluid choices. Here, we briefly summarize some of the physiology and history of albumin use in intensive care before offering some evidence-based guidance for albumin use in critically ill patients.

Figure 1

Schematic illustration of metabolism of albumin in healthy adults. GI, gastrointestinal.

Figure 2

Schematic illustration of the current understanding of vascular barrier function within the high-pressure segment of the vascular system. For explanation, see text. White arrows, hydrostatic pressure (HP) gradients towards the interstitial space; thick black arrow, inward directed oncotic force across the endothelial surface layer; thin black arrow, small flux of protein low ultrafiltrate. EC, endothelial cell; EG, endothelial glycocalyx; ESL, endothelial surface layer; IS, interstitial space; PF, protein free space beneath the endothelial surface layer; RC, red blood cell; VL, vascular lumen.

Figure 3

Some of the key substances transported by albumin. NO, nitric oxide; NSAID, nonsteroidal anti-inflammatory drug.