The cardiovascular and oncotic effects of albumin infusion in premature infants.

We determined the oncotic and cardiovascular effects of a standardised infusion of human albumin (1.2 g/kg over 2 h as a 20% solution) in 12 premature infants on 18 occasions when hypovolaemia was suspected on clinical grounds. Blood volume increased by a median value of 15.5%, and fell to preinfusion values by 3 h post infusion in all but four cases. Albumin concentration and colloid osmotic pressure rose during infusion and remained raised even when blood volume had fallen to preinfusion levels. Blood pressure rose in 3 cases only and heart rate fell by greater than 5 beats/min in 6 cases. Indices of long- and short-term heart rate variability were unchanged, but blood pressure variability fell in the second hour of infusion (P = 0.03), an effect which was independent of changes in lung inflation. No changes in blood gases or oxygenation occurred during infusion and no evidence of pulmonary oedema was found. There were wide variations in oncotic and cardiovascular responses to the standardised infusion both between and within subjects. When human albumin is infused in this manner some protection against respiration-induced variability in blood pressure can result, but the circulatory response may prove difficult to predict in the individual.