Albumin infusion for the critically ill – is it beneficial and, if so, why and how?

Introduction Human albumin is used for volume expansion and resuscitation and to correct hypoalbuminemia [1]. Hypoalbuminemia is frequent in sepsis and is a strong predictor of mortality and morbidity [2]. Fluid volume expansion and resuscitation of the critically ill with albumin has been recommended by the UK National Institute for Health and Care Excellence and the Surviving Sepsis Campaign (grade 2C), although the evidence for these recommendations is not strong [1,3-8] and use of albumin to correct or improve hypoalbuminemia remains controversial [7,8] despite the fact that albumin is safe to use for the critically ill [8]. Albumin mobilizes polyunsaturated fatty acids (PUFAs) from the liver and other tissues, and thus enhances the formation of cytoprotective bioactive lipids – lipoxins, resolvins and protectins – that, in turn, suppress production of proinflammatory prostaglandins, free radicals and cytokines. The beneficial actions of albumin thus depend on its ability to mobilize PUFAs and the formation of adequate amounts of lipoxins, resolvins and protectins. For those who have hepatic and tissue deficiency of PUFAs, albumin fails to mobilize PUFAs and formation of lipoxins, resolvins and protectins will be inadequate, which may explain failure of the beneficial actions of albumin in the critically ill.