ABSTRACT
<p><b>OBJECTIVE</b>To explore the effects of blood transfusion on the vital signs and heart function in preterm infants with anemia.</p><p><b>METHODS</b>A total of 40 anemic preterm infants with gestational age less than 34 weeks who accepted blood transfusion one week after birth were enrolled for a prospective cohort study. Left ventricular ejection fraction (LVEF), fractional shortening (FS), stroke volume (SV), and cardiac output (CO) were determined with portable ultrasonic equipment before blood transfusion and within 24 hours after blood transfusion. Apnea was detected and the times of apnea were recorded within 24 hours before and after blood transfusion. The resting body temperature and blood pressure were also determined before and after blood transfusion. Additionally the resting heart rate, respiratory rate, and transcutaneous oxygen saturation were recorded within 4 hours before and after blood transfusion.</p><p><b>RESULTS</b>The heart rate and respiratory rate decreased significantly within 4 hours after blood transfusion (P<0.05). Four infants had apnea within 24 hours before blood transfusion, and nobody had apnea within 24 hours after blood transfusion. The systolic pressure, diastolic pressure, mean arterial pressure, and body temperature showed no significant changes after blood transfusion (P>0.05), and the LVEF, SV, CO, and FS showed no significant changes after blood transfusion as well (P>0.05).</p><p><b>CONCLUSIONS</b>Blood transfusion can improve the clinical symptoms and shows no significant effect on the heart function in preterm infants with anemia.</p>