Physiological aspects of the role of human albumin in the treatment of chronic and acute blood loss.

Human albumin is the most important oncotic-active protein (1 g albumin attaches 18 g water). It is essential for the water exchange between intra- and extracellular space and for homeostasis. The physiological distribution of albumin, its daily exchange and degradation are being discussed. At the example of normo- and hypovolaemic patients and acute blood-loss the stabilising effect on the blood-volume and the hemodynamic efficacy of human albumin are shown. Human albumin was infused into patients with hypoproteinemia and hypovolaemia as well as to surgical patients with normovolaemia. Volunteers received albumin after an acute blood-loss. Under and after the albumin-infusion the albumin disappeared partly from the blood-stream. The loss to the extravascular compartments was greatest among patients with hypoproteinemia. Among volunteers with experimental blood-loss the infused volume disappeared in an amount of 45 to 106 ml per hour. When human albumin is given over a longer period the synthesis of endogenous albumin and of globulins may be inhibited or at least depressed. Albumin has a positive effect on the hemodynamic. The cardiac-output and the stroke volume increased. The peripheral resistance fell in the same time. Renal filtration rate and the urine volume increased, in contrast renal resistance was lowered.