Objective To explore the impact of different delay time of umbilical cord ligation on the outcome of preterm infants.Methods A total of 266 preterm infants born in the obstetric department of this hospital from January 2021 to December 2022 were selected as the research subjects and divided into the in-stant group(umbilical cord ligation immediately after birth,n=53),30 s group(delayed umbilical cord liga-tion for 30 s,n=50),60 s group(delayed umbilical cord ligation for 60 s,n=55),90 s group(delayed umbili-cal cord ligation for 90 s,n=55)and 120 s group(delayed umbilical cord ligation for 120 s,n=52)according to the random number table method.The Hb and HCT levels and the incidence rates of anemia,blood transfu-sion,hyperbilirubinemia,intracranial hemorrhage,necrotizing enterocolitis(NEC)and bronchopulmonary dys-plasia(BPD)after birth were compared among 5 groups.Results The Hb and HCT levels at 24 h after birth in the 60,90,120 s groups were higher than those in the instant group and 30 s group,moreover the 120 s group was higher than the 60 s group and 90 s group,and the differences were statistically significant(P＜0.05).The anemia incidence rate and blood transfusion rate in the 60,90,120 s groups were lower than those in the instant group and 30 s group,and the differences were statistically significant(P＜0.05).The hyperbil-irubinemia incidence rate in the 120 s group was higher than that in the other 4 groups,and the difference was statistically significant(P＜0.05).The intracranial hemorrhage incidence rate in the 60,90,120 s groups were lower than those in the instant group and 30 s group,and the differences were statistically significant(P＜0.05).The NEC incidence rate in the 60 s and 90 s group was lower than that in the instant group and 30 s group,but the 120 s group was higher than that in the other 4 groups,and the differences were statistically significant(P＜0.05).The BPD incidence rate had no statistical difference among 5 groups(P＞0.05).Con-clusion Delayed umbilical cord ligation for 60 s or 90 s could improve the outcomes of preterm infants.

Objective:To observe the clinical efficacy and safety of non-invasive high frequency oscillatory ventilation(NHFOV) on the early respiratory support in very low birth weight infants with respiratory distress syndrome(RDS).Methods:It was a prospective cohort study involving very low birth weight infants with RDS admitted to the Central Hospital of Chongqing Three Gorges from January 2017 to January 2020 with a gestational age of 28-32 weeks.According to the applied non-invasive respiratory support, very low birth weight infants with NRDS were divided into control group[continuous positive airway pressure (CPAP) group]and observation group(NHFOV group). Therapeutic effect, complications and adverse effects between 2 groups were compared.Results:A total of 78 very low birth weight infants with RDS were included, among which 38 cases were supported with NHFOV group and 40 cases were CPAP group.(1) Therapeutic efficacy: there were no significant differences in the use of pulmonary surfactant and death rate between 2 groups (all P>0.05). Compared with the CPAP group, patients in the NHFOV group had significantly lower incidence of non-invasive ventilation failure(4 cases vs.13 cases), duration of non-invasive ventilation [(7.60±1.68) days vs. (10.75±2.38) days], duration of oxygen exposure [(12.34±2.66) days vs.(17.20±4.36) days] and times of apnea [(1.68±1.57) times/day vs.(4.80±2.60) times/day] (all P<0.05). There was no significant difference in the incidence of complications between 2 groups (all P>0.05). (2) Adverse events: compared with CPAP group, patients in the NHFOV group had significantly lower incidence of abdominal distension [13 cases(34.2%) vs. 25 cases (62.5%)], delayed duration of respiratory secretion disappearance [(12.65±2.33) days vs.(7.87±2.70) days], low viscosity of secretions [thin sputum, 31 cases (81.6%) vs.22 cases (55.0%); ropy sputum, 7 cases (18.4%) vs.18 cases(45.0%)], and less airway obstruction [2 cases (5.2%) vs.15 cases (37.5%)] (all P<0.05). No significant difference in the incidence of nasal septum injury was detected between 2 groups (1 case vs.0) ( P>0.05). Conclusions:NHFOV is safe and effective in the early application of NRDS in very low birth weight infants with RDS, which has less adverse events.It is expected to be used in the treatment of children with frequent apnea and a large number of respiratory secretions that is prone to obstruction.