The haemodynamic effects of dopamine and volume expansion in sick preterm infants. Randomised controlled trial of plasma protein fraction versus dopamine in hypotensive very low birthweight infants.
To determine the haemodynamic effects of dopamine and volume expansion in preterm neonates. Effect parameters were mean arterial blood pressure (MABP), left ventricular output (LVO) and global cerebral blood flow (CBF).
                In a randomised, clinical control trial 36 preterm neonates were randomised to receive either dopamine 5 microg/kg per min, volume expansion with albumin 20% 15 ml/kg or no treatment. Parameters were measured before and 2 h after initiation of treatment.
                Dopamine was effective in increasing MABP; both treatments increased LVO, whereas no significant difference between the treatment groups and the control group could be demonstrated with regard to CBF.
                No effect on global cerebral blood flow could be demonstrated in this study, despite significant effects on systemic circulatory parameters. However, the variance on the measurement of cerebral blood flow indicates that a small but clinically significant effect may have been overlooked. Around 20% of very low birthweight infants admitted to a neonatal intensive care unit become hypotensive within 24 hours of their admission. Standard treatment is either expansion of the circulating volume by the infusion of plasma protein fraction or by using dopamine to improve cardiac function. The purpose of this study was to investigate by a randomised controlled trial which was the most appropriate treatment. Thirty nine infants were randomised to receive either plasma protein fraction or dopamine as first line treatment if they became hypotensive within 24 hours of admission to the neonatal intensive care unit. Seventeen of 19 (89%) infants responded to dopamine, whereas only 9/20 (45%) responded to plasma protein fraction. The median dose of dopamine needed to increase the blood pressure to at least the 10th centile was 7.5 micrograms/kg/min and was infused for a median duration of 18 hours. These observations suggest that dopamine should be used earlier in the treatment of these infants than has previously been recommended.
Dopamine was more successful than albumin at correcting low BP in hypotensive preterm infants, many of whom had already received volume. Neither intervention has been shown to be superior at improving blood flow or in improving mortality and morbidity in preterm infants. The trials do not allow any firm conclusions to be made as to whether or when volume or dopamine should be used in preterm infants.