RT Journal Article
SR Electronic
T1 Haematocrit and red blood cell transport in preterm infants: an observational study
JF Archives of Disease in Childhood - Fetal and Neonatal Edition
JO Arch Dis Child Fetal Neonatal Ed
FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health
SP F150
OP F155
DO 10.1136/fn.82.2.F150
VO 82
IS 2
A1 Pladys, P
A1 Beuchée, A
A1 Wodey, E
A1 Tison, L
A1 Bétrémieux, P
YR 2000
UL http://fn.bmj.com/content/82/2/F150.abstract
AB AIMS To test whether cardiac output acts as a compensatory response to changes in haematocrit.METHODS A cohort of 38 preterm infants (27–31 weeks' gestation) was studied with repeated Doppler measurements of left ventricular output during the 1st month of life. Red blood cell transport was calculated when the duct was closed.RESULTS Multiple regression analysis showed that left ventricular output correlated negatively with haematocrit when the duct was closed (n = 84) and when it was open (n = 59). The influence of an increase of 10% in haematocrit absolute value on mean (SD) left ventricular output was estimated at −55 (11) ml/kg/min. Mean (SD) red blood cell transport was 132 (30) ml/kg/min with a mean (SD) intra-individual variability of 20% (8.8%). Red blood cell transport was increased more frequently by left ventricular output than by haematocrit. Haematocrit and left ventricular output but not red blood cell transport were dependent on postnatal age.CONCLUSION These results suggest that in preterm infants cardiac output adaptation is effective in attenuating the effects of red blood cell mass variations on systemic oxygen carrying capacity. Key messagesKey messagesRed cell transport is an estimation of oxygen carrying capacityThe effects of red blood cell mass variations on oxygen carrying capacity depend on the compensatory response provided by cardiac output adaptation