Plasma N-terminal pro-B-type natriuretic levels and changes of pulmonary flow parameters in asphyxial preterm infants

Objective To investigate the plasma level of NT-proBNP and the changes of pulmonary arterial blood flow parameters in asphyxial preterm infants and to provide reference for early clinical intervention.Methods Comparing with 20 normal preterm infants in the control group,plasma levels of NT-proBNP and CK-MB of 60 preterm infants with asphyxia were tested using ELISA.Doppler echocardiography was employed to detect the anatomical and dynamic changes of aortic and pulmonary blood flow.These results were evaluated for diagnosing cardiac dysfunction after asphyxia in preterm infants.Results The plasma levels of NT-proBNP(pmol/L) in both mild and severe asphyxia group [(217±46),(359±56)] were higher than the control group(123±25)(P0.05 and0.01),and the severe asphyxia group had higher NT-proBNP level than the mild group(P0.05).The plasma level of CK-MB in the severe asphyxia group was higher than the control group(P0.05).There was no significant difference of CK-MB level between the severe asphyxia group and the mild asphyxia group,and no significant difference existed between the mild asphyxia group and the control group.The severe asphyxia group had a shorter acceleration time and a higher diminished ratio(AT/ET) of acceleration time(AT) versus ejection time(ET) than the control group and the mild asphyxia group(P0.01 and 0.05),and the difference were more significant between the severe asphyxia group and the control group(P0.05).Conclusion Asphyxia could increase the plasma level of NT-proBNP and decrease the pulmonary AT and AT/ET in preterm infants.