Objective To investigate the changes of cardiac function at pre -and post -treatment in preterm infants with patent ductus arteriosus (PDA)in order to guide drug treatment.Methods Totally 84 preterm infants with PDA admitted to Neonatal Intensive Care Unit of Xuzhou Hospital Affiliated to Medical College of Southeast University from July 201 2 to June 201 4 were divided into 4 groups according to treatment drug:Ibuprofen group (27 cases),Indo-methacin group (24 cases),control group (1 1 cases),and Paracetamol group (22 cases).Patients were also divided into symptomatic PDA group (38 cases)and asymptomatic PDA group (46 cases)according to severity;PDA closed group (69 cases)and PDA unclosed group (1 5 cases)according to sequel.The level of plasma brain natriuretic pep-tide (BNP),cardiac troponin I (cTnI),correct QT intervals dispersion (QTcd)were monitored pre -and post -treat-ment.Data were analyzed by using SPSS 1 9.0 software.Results Three cardiac markers at post -treatment were of no significant difference among 4 treatment drugs.The changes of the cTnI and QTcd at pre -and post -treatment were of no significance.The level of BNP in symptomatic PDA group was significantly higher than that in asymptomatic PDA group at pre -treatment [(378 ±94)ng/L vs (1 47 ±75)ng/L,t =2.584,P =0.01 4].In the symptomatic PDA group,the level of BNP at post -treatment [(1 82 ±81 )ng/L]was significantly decreased than that at per -treatment (t =2.741 ,P =0.009).In the asymptomatic PDA group,there was no significant difference between the pre - and post -treatment [(1 21 ±61 )ng/L]in the level of BNP (t =1 .254,P =0.207).There was no significant difference in the level of BNP at per -treatment between PDA closed group and PDA unclosed group [(274 ±91 )ng/L vs (289 ± 87)ng/L,t =-0.874,P =0.391 ].In PDA closed group,the level of BNP at post -treatment [(1 21 ±74)ng/L] was significantly decreased compared with that at per -treatment (t =3.580,P =0.000).In PDA unclosed group, there was no significant difference between the pre - and post -treatment [(245 ±74)ng/L]in the level of BNP (t =0.854,P =0.392).Conclusion Early medication intervention for symptomatic PDA of preterm infants is benefi-cial for the closure of PDA and for attenuating negative effects on cardiac function of PDA.

Objective To study the effect of three different modes of non-invasive positive pressure ventilation on cardiac indices of premature infants with respiratory distress syndrome (RDS).Method From January 2014 to October 2015,preterm infants who had RDS received intubation-pulmonary surfactantextubation in the neonatal intensive care unit of the Hospital were randomly assigned (by random number table) to three groups based on the primary mode of ventilation:nasal continuous positive airway pressure (NCPAP),bi-level positive airway pressure (BiPAP),and synchronized bi-level positive airway pressure (SBiPAP).The mean airway pressure (MAP) were about 6 cmH2O in the three groups.The level of plasma B-type natriuretic peptide (BNP),cardiac troponin Ⅰ (cTnI),and correct QT intervals dispersion (QTcd) were monitored before and 42-54 h after non-invasive ventilation.Result There were 173 cases in our study,59 of which in NCPAP group,56 in BiPAP group,and 58 in SBiPAP group.The plasma BNP level at 42-54 h after non-invasive ventilation in the three groups were all higher than that before non-invasive ventilation [NCPAP group:(247.9 ± 137.9) ng/L vs.(182.5 ± 1 10.7) ng/L,P =0.007;BiPAP group:(258.5 ± 131.2) ng/L vs.(182.6 ± 105.0) ng/L,P ＜ 0.001;and SBiPAP group:(260.9 ± 159.7) ng/L vs.(177.5 ± 101.5) ng/L,P =0.002].After 42-54 h non-invasive ventilation,there were no significant changes of plasma cTnI level and QTcd in all the three groups (all P ＞ 0.05).The level of plasma BNP,cTnI,and QTcd among the three groups before and after 42-54 h non-invasive ventilation all showed no significant differences statistically (all P ＞ 0.05).Conclusion Longer duration (42-54 h) of non-invasive positive pressure ventilation (MAP:6 cmH2O) in preterm infants with RDS may lead to increased plasma BNP level,and may affect their cardiac function.However,it may not lead to serious myocardial damage and abnormality of ventricular repolarization.There were no significant differences in cardiac indices of premature infant with RDS among NCPAP,BiPAP,and SBiPAP group with the same MAP.

Objective:To assess the effects of noninvasive positive pressure ventilation on premature infants' cardiac function using Tei index combined with corrected QT dispersion (QTcd) and B- type natriuretic peptide (BNP).Methods:This prospective study involved premature infants from 28 to 32 weeks of gestational age diagnosed with respiratory distress syndrome (RDS) and treated with noninvasive positive pressure ventilation in the Neonatal Intensive Care Unit of Xuzhou Central Hospital from December 2017 to December 2020. According to the mean airway pressure (MAP) during noninvasive positive pressure ventilation, the patients were divided into the low-pressure group (≤6 cmH 2O, 1 cmH 2O=0.098 kPa), medium-pressure group (>6-<9 cmH 2O), and high-pressure group (≥9 cmH 2O). The right ventricular Tei index, QTcd, and blood BNP were monitored during the first 2 h of noninvasive positive pressure ventilation and 12 h after continuous ventilation with stable MAP. Chi-square test, one-way analysis of variance, paired t-test, and Pearson product-moment correlation coefficient were adopted for statistical analysis. Results:Totally 178 premature infants were enrolled, including 75 in the low-pressure, 62 in the medium-pressure, and 41 in the high-pressure group. After continuous ventilation with stable MAP for 12 h, the right ventricle Tei index and QTcd in the high-pressure group were higher than those in the medium- and low-pressure group [Tei index: (0.38±0.05) vs (0.33±0.04) and (0.33±0.04), F=29.18; QTcd: (27.6±4.2) vs (22.8±4.4) and (22.2±4.2) ms, F=23.26, all P<0.001], and the comparison between the medium- and the low-pressure group did not differ significantly. No significant difference was observed in blood BNP levels among the three groups ( F=1.33, P=0.267). The right ventricle Tei index and QTcd increased in the high-pressure group after continuous ventilation with stable MAP for 12 h as compared with those within the first 2 h of noninvasive positive pressure ventilation [Tei index: (0.38±0.05) vs (0.34±0.04), t=－6.61; QTcd: (27.6±4.2) vs (23.4±4.4) ms, t=－5.06, all P<0.001]. However, the figures did not change significantly in the medium- or the low-pressure group (all P>0.05). There were no significant changes in blood BNP in the three groups (all P>0.05). The right ventricle Tei index and QTcd were moderately positively correlated with MAP ( r=0.56 and 0.50, both P<0.001). Conclusions:For the premature infants with RDS, noninvasive positive pressure ventilation has no significant effect on the cardiac function when MAP is less than 9 cmH 2O, but would have a certain effect on the right ventricular function when used at higher pressure (MAP≥9 cmH 2O) and for longer time (>12 h).