Albumin and the kidney, a friend or foe

Albumin preparations are the most common colloids used in critically ill patients worldwide. This review is to provide the physiological rationale and evidence for benefits and harms in different clinical settings.

There is a strong physiological rationale for intravenous albumin administration in critically ill patients. Iso-oncotic and hyperoncotic albumin have both been used for volume resuscitation and to maintain effective plasma volume at an optimal fluid balance. This practice, however, has not proven to be superior to using crystalloids or balanced solutions with no significant reduction in kidney injury or time on vasopressors. In patients with septic shock and hypoalbuminaemia, albeit limitations, subgroup analysis of a randomized trial suggested reduced mortality with albumin supplementation. Similarly, guidelines strongly recommend the use of albumin in hepatic-induced kidney injury and hepatorenal syndrome. Albumin also improved diuresis when combined with diuretics and may improve intradialytic hypotension. Conversely, hyperoncotic albumin infusion increased the risk of kidney injury and red cell transfusion in high-risk cardiac surgery.

Hyperoncotic, and albumin administration in general, is a double-edged sword, its use should be tailored to specific clinical scenarios. The use of hyperoncotic albumin in high-risk cardiac surgery should be discouraged.