Abstract: Objective To monitor the dynamic changes in the following indexes with ultrasonic cardiac output monitor(USCOM) in the neonates without circulatory disorder, including cardiac output, stroke volume index(SVI), systemic vascular resistance index(SVRI), cardiac index(CI),ejection fraction(EF) and stroke volume variation(SVV), and to study the reliability of USCOM for dynamic monitoringMethods A total of 575 neonates without circulatory disorder treated in our Neonatal Department from November 2013 to April 2015 were included, and the dynamic changes in CO,SVI,CI,SVRI,EF and SVV of these neonates were determined on 1,3,7 and 14 days after birth. Meanwhile these neonates were divided into two groups: group 1 with body weight over 2 500 g and group 2 no more than 2 500 g; they were also divided into 4 groups based on their days of age, which were group 11,group 13,group 17 and group 114,and group 21,group 23,group 27 and group 214.The results of the determination in aortic region and pulmonary artery region were compared among the neonates of the groups.Results In the neonates of group 1, there was statistical difference in ASVI and ASVRI between 1-day neonates and 3-day neonates(P<0.05), while there was no statistical difference in the other indexes(P>0.05); only ACI had statistical difference between 3-day and 7-day neonates(P=0.03), and no statistical difference existed in the other indexes; there was no statistical difference in FEF, ASVV or FSW between 7-day and 14-day neonates(P>0.05), while the other indexes had statistical difference(P<0.05).In group 2,there was statistical difference in AEF,ACI,FSVI,FCO,FCI and FSVRI between 1-day and 3-day neonates(P<0.05),while there was no statistical difference in the other indexes(P>0.05); there was statistical difference in ACI,FCO and FCI between 3-day and 7-day neonates(P<0.05), while the difference in the other indexes was not statistically significant(P>0.05);between 7-day and 14-day neonates, there was no statistical difference in any index(P>0.05).Conclusion For the neonates without circulatory disorder with body weight over 2 500 g at 3 to 7 days after birth and those no more than 2 500 g at 7 to 14 days after birth, there is no big difference in hemodynamic indexes, so the hemodynamic monitoring with USCOM is of some significance, but the changes in hemodynamic indexes in those at 1 to 3 days after birth are not stable, so there is not much significance in the monitoring.

Key words: Noninvasive hemodynamies monitoring, USCOM, Cardiac output, Systemic vascular resistance, Neonate