Monitoring Of Pulmonary Function In Premature Infants With Different Degrees Of Bronchopulmonary Dysplasia

Purpose:Through dynamic follow-up of pulmonary function in premature infants with different degrees of bronchopulmonary dysplasia(BPD),the types of tidal respiratory and pulmonary dysfunction in early postnatal period,the characteristics and evolution of important respiratory parameters were understood,in order to provide reference for prevention,diagnosis,treatment and prognosis of BPD in clinic.Methods:1.Selection of Research ObjectsFrom June 2016 to October 2018,we followed up the preterm infants both in neonatal intensive care unit(NICU)and neonatal outpatient department of Affiliated Hospital of Qingdao University.Among them,64 preterm infants in BPD group were observed group,35 preterm infants in non-BPD group were control group.Premature infants in BPD group were divided into mild group(which consists of 32 preterm infants)and moderate to severe group(which consists of 32 preterm infants)according to the degree of dependence on oxygen at corrected gestational age of 36 weeks or at the discharge time.Exclude cases that do not meet the requirements.2.Research methods In our hospital's neonatal outpatient department,we conducted the long-term follow-up study.We used German Kangxun Pulmonary Function Instrument to examine the tidal respiratory pulmonary function of premature infants in non-BPD group,mild BPD group and moderate to severe BPD group at the corrective age of 1 month,3 months and 6 months.We recorded each tidal breathing parameter and tidal breathing flow-volume loop to compare and evaluate the pulmonary function of premature infants in non-BPD group,mild BPD group and moderate to severe BPD group.Results:1.General information1.1 Gestational Age?Birth Weight and Birth LengthA total of 99 preterm infants were included in this study,including 35 preterm infants in non-BPD group and 64 preterm infants in BPD group.The differences in gestational age(GA),birth weight(BW)and birth length between non-BPD group and BPD group were not statistically significant(P> 0.05).1.2 Comparison of body weight and length of each group at the corrective age of 1monthAt the corrective age of 1 month,the weight of moderate to severe BPD group was lighter than that of non-BPD group and mild BPD group.The difference was statistically significant(P< 0.05).This suggested that from birth to the corrective age of 1 month,the weight growth of moderate to severe BPD group was slower than that of non-BPD group and mild BPD group.There were no significant differences in body length between the three groups(P> 0.05).1.3 Comparison of body weight and length of each group at the corrective age of 3monthsAt the corrective age of 3 months,there were no significant differences in body weight and body length between non-BPD group,mild BPD group and moderate to severe BPD group(P> 0.05).This indicated that the weight catch-up growth of children in moderate to severe BPD group was more obvious from the corrective age of 1 month to the corrective age of 3 months.1.4 Comparison of body weight and length of each group at the corrective age of 6monthsAt the corrective age of 6 months,the body length of mild BPD group and moderate to severe BPD group was shorter than that of non-BPD group,and the difference was statistically significant(P< 0.05).This indicated that the body length's growth rate of children in BPD group was slower than that of non-BPD group from the corrective age of 3 months to the corrective age of 6 months.There were no significant differences in body weight among the three groups(P> 0.05).2.Results of pulmonary function2.1 At the corrective age of 1 monthAt the corrective age of 1 month,the lung function indexes of non-BPD group,mild BPD group and moderate to severe BPD group were compared.The TEF25 of moderate to severe BPD group was lower than that of non-BPD group,the difference was statistically significant(P< 0.05);the TEF50 of non-BPD group was higher than that of mild BPD group and moderate to severe BPD group,the difference was statistically significant(P< 0.05).There were no significant differences in other indexs(P> 0.05).2.2 At the corrective age of 3 months At the corrective age of 3 months,the lung function indexes of non-BPD group,mild BPD group and moderate to severe BPD group were compared.The respiratory rate(RR)of moderate to severe BPD group was faster than that of non-BPD group,the difference was statistically significant(P< 0.05);the inspiratory time(Ti)of non-BPD group was shorter than that of mild BPD group and moderate to severe BPD group,the difference was statistically significant(P< 0.05);the peak time(Tpef)of moderate to severe BPD group was shorter than that of non-BPD group,the difference was statistically significant(P< 0.05);the Tpef/Te and Vpef/Ve of moderate to severe BPD group were less than that of non-BPD group,the differences were statistically significant(P<0.05).2.3 At the corrective age of 6 months At the corrective age of 6 months,the lung function indexes of non-BPD group,mild BPD group and moderate to severe BPD group were compared.The respiratory rate(RR)of moderate to severe BPD group was still faster than that of non-BPD group,the difference was statistically significant(P< 0.05);the mid expiratory flow(TMMEF)of moderate to severe BPD group was lower than that of non-BPD group,the difference was statistically significant(P < 0.05);the TEF25 of moderate to severe BPD group was lower than that of mild BPD group,the difference was statistically significant(P <0.05).Conclusions:1.Compared with non-BPD preterm infants,the respiratory rate(RR)of preterm infants in BPD group increased significantly,especially in moderate to severe BPD group.This indicated that BPD group needs to increase respiratory rate(RR)to ensure minute ventilation volume(MV).2.The TEF25 and TEF50 of moderate to severe BPD group were less than those of non-BPD group at the corrective age of 1 month,indicating that there was small airway gas flow obstruction in moderate to severe BPD group at the corrective age of 1month.3.The Tpef,Tpef/Te and Vpef/Ve in moderate to severe BPD group were less than those in non-BPD group at the corrective age of 3 months,indicating that there was small airway obstruction in moderate to severe BPD group at the corrective age of 3months.The Ti in non-BPD group was shorter than that in moderate to severe BPD group,which indicated that children in moderate to severe BPD group needed to prolong inspiration time to increase oxygen inhalation.4.At the corrective age of 6 months,the TMMEF in moderate to severe BPD group was less than that in non-BPD group and TEF25 was less than that in mild BPD group,which indicated that the small airway gas flow obstruction in moderate to severe BPD group lasted to the corrective age of 6 months.