Abstract: Objective To explore the effects of blood transfusion on the vital signs and hemodynamics in preterm infants with anemia. Methods A total of 60 anemic preterm infants with gestational age less than 34 weeks who accepted blood transfusion one week after birth were enrolled for the study from January 2013 to June 2015.Each infant had 2sets of vital and echocardiographic evaluations within 24 h after transfusion.The following data were collected：respiratory rate in breaths/min,heart rate in beats/min,diastolic,systolic,and mean arterial blood pressures （DBP,SBP,and MBP） in mmHg,ventilation indexes,oxygenation and lactic acid,and left ventricular output （LVO） in ml/min/kg. Results The heart rate and respiratory rate decreased significantly within 24 h after blood transfusion （P<0.05）.The systolic pressure,diastolic pressure,mean arterial pressure,and body temperature were not statistically different in pre- and post-transfusion （P>0.05）.The LVO and SV showed no significant changes after transfusion （P>0.05）. Conclusions Blood transfusion can decrease heart rate and respiratory rate and shows no significant effect on the hemodynamics in preterm infants with anemia.And no significant improvement was noted in oxygenation following blood transfusion in preterm infants.

Key words: Blood transfusion, Anemia, Preterm infant