The Establishment Of Critical Neonatal Network And The Multicenter Study Of Diagnostic And Therapeutic Status Of Critical Neonates In Chongqing District

Objective: After the change of medical model from empiricism to evidence-based medicine(EBM),the development of EBM need a lot of multicenter study providing high quality of clinic evidence.During the developmental process of multicenter study in neonatology,a special study model named “network” was gradually developed in developed countries,and became a major model of cohort study,and was continuously seen as a tool for evaluating the quality of NICU management.This work is still in the initial stage in the domestic.This study is aimed to establish a Critical Neonatal Network and furtherly to investigate the present status of critical neonates' diagnosis and treatment so as to improve the management of critical neonates.Methods: This study is a multicenter epidemiological investigation based on the Chinese Critical Neonatal Network.The network was developed on the ASP.NET platform.Meeting at least one of the following requirements was seen as the inclusion criteria for this study: 1.the small preterm with birth weight > 1500 grams or gestational age > 32weeks;2.proven sepsis or clinic diagnostic sepsis;3.necotizing enterocolitis(NEC);4.mechanical ventilation >4 hours.Twenty two hospitals in Chongqing joined the network and submitted clinic material from Jan.2013 to Dec.2015.The general information,incidence of disease,survival rate and diagnosis and treatment strategies were analyzed,which were compared with the report of the Canadian Neonatal Network(CNN)in 2014.Results: The Critical Neonatal Network was runned online after testing.Three thousand five hundred and five cases were obtained,there were 1028 infants(29.3%)was the small preterm,1673 infants(47.7%)was diagnosed as sepsis,620 infants(17.7%)was diagnosed as NEC and 1650 infants underwent mechanical ventilation for more than four hours.The mean hospitalization time was 14(7.0,23.0)days,and the overall cure rate was 53.4%.(1)the small preterm with birth weight >1500grams or gestational age >32weeks: the mean gestational age of this cohort was 30.1±4.3weeks,the mean birth weight was 1436.2±379.0grams.Extremely low birth weight infants and extremely premature infants accouted for 4.9% and 5.3%.The survival rates for different gestational age group and for different birth weight group were significantly lower than 2014 CNN report.Of all the infants,406 cases(39.5%)was given prenatal administration of dexamethasone,and 191 cases(18.6%)was given ful dose of dexamethasone.There were 829 infants(80.6%)taking the cranical ultrasound examination and 555 infants(54.0%)accomplishing it within the first three days of life.Stage I/II periventricular-intraventricular hemorrhage(PIVH)was found in 29.9% of this cohort,and StageIII/VI PIVH was accounted for 8.1%,which was lower than 2014 CNN report.A total of 528 infants(51.4%)was diagnosed as neonatal respiratory distress syndrome,among them 414 infants(78.4%)were given the pulmonary surfactant replacement therapy,211 infants(40.0%)were treated with INSURE technology,273 infants(51.7%)were treated with nCPAP.The incidence rate of classic BPD in this cohort was 16.4%.and the new BPD was 13.7%,which is low than 2014 CNN report.The patent ductus arterious(PDA)was found in 58.9% of the small preterm,and 4.7% of them was intervened,the intervention rate was significantly lower than the 2014 CNN report.Retinopathy of prematurity(ROP)was screened in 37.5% infants,stage I-II ROP was found in 95 cases(24.7%)and stage III ROP was found in 4 cases(1.0%).Laser therapy was done in 10 cases,the screening rate and the intervention rate for ROP were all low than the 2014 CNN report.There were 116 infants diagnosed as NEC,and 30 infants(2.9%)reached the criteria for II-III stage NEC,only four infants of the cohort was treated with surgery,which is lower than the 2014 CNN.(2)proven sepsis and clinic diagnosic sepsis: The main pathogen of early onset sepsis was G-bacterium,and the Escherichia coli and Klebsiella was the main species.The main pathogen of late sepsis was G+ bacterium,and the Coagulase negative staphylococcus aureus was the top species.The late onset sepsis appeared in the preterm more than in the early onset,while the latter had more cases experienced respiratory failure.The top three of antibiotics used in management of sepsis was penicillin(including Semisynthetic penicillins,66.9%),3rd or 4th generation of cephalosporin(47.9%)and Carbapenems(28.2%).The mean duration of Carbapenems administration was 10.8±9.2 days.The incidence rate of NEC and mortality didn't differ between the group with intravenous immunoglobulin and the group without intravenous immunoglobulin.(3)NEC:There is no difference for incidence rate for NEC,surgery rate and mortality among the gestational age group of<32weeks,32weeks~ and ?37weeks(P>0.05).The term infants with proven NEC appeared more abdorminal distension than the preterm.The positive rate of specific sign of abdominal X film was more higher in the infants with lower gestational age.(4)mechanical ventilation more than four hours: the mechanical ventilator associated complication was listed accoding to the incidence rate: ventilator associated pneumonia(1.2%),air leak syndrome(1.0%),pulmonary atelectasis(0.3%)and BPD(0.1%).The incidence rate of mechanical ventilator associated complication was much higher in the invasive mechanical ventilation group than in the nCPAP group.The nCPAP group had lower degree of disease severity and lower mortality.The infants requiring higher initial oxygen concentration of mechanical ventilation,had higher rate of taking invasive mechanical ventilation and had higher mortality.Conclusion: This study suggests that the establishment of Critical Neonatal Network and to carry out the multicenter study based on it is feasible.The proportion of extremely low birth weight infants and extremely premature infants among the small preterm is low in this cohort.A large gap of survival rate of the small preterm between Chongqing and CNN exists.Some clinic strategies,such as taking cranial ultrasonic examination within the first 3 days more earlier,nCPAP supportive treatment,ROP screening and intervention,and collaboration of physician and surgeon on management of NEC and other aspects need to be further strengthened.Meanwhile,increasing the use of non-invasinve mechanical ventilation is helpful to reduce mechanical ventilation associated complication and improve the prognosis.