[Establishment of a predictive nomogram model for predicting the death of very preterm infants during hospitalization]. / 极早产儿住院期间死亡的列线图预测模型的建立.

OBJECTIVES: To establish a nomogram model for predicting the risk of death of very preterm infants during hospitalization. METHODS: A retrospective analysis was performed on the medical data of 1 714 very preterm infants who were admitted to the Department of Neonatology, the Third Affiliated Hospital of Zhengzhou University, from January 2015 to December 2019. These infants were randomly divided into a training cohort (1 179 infants) and a validation cohort (535 infants) at a ratio of 7∶3. The logistic regression analysis was used to screen out independent predictive factors and establish a nomogram model, and the feasibility of the nomogram model was assessed by the validation set. The area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve analysis (DCA) were used to assess the discriminatory ability, accuracy, and clinical applicability of the model. RESULTS: Among the 1 714 very preterm infants, 260 died and 1 454 survived during hospitalization. By the multivariate logistic regression analysis of the training set, 8 variables including gestational age <28 weeks, birth weight <1 000 g, severe asphyxia, severe intraventricular hemorrhage (IVH), grade III-IV respiratory distress syndrome (RDS), and sepsis, cesarean section, and use of prenatal glucocorticoids were selected and a nomogram model for predicting the risk of death during hospitalization was established. In the training cohort, the nomogram model had an AUC of 0.790 (95%CI: 0.751-0.828) in predicting the death of very preterm infants during hospitalization, while in the validation cohort, it had an AUC of 0.808 (95%CI: 0.754-0.861). The Hosmer-Lemeshow goodness-of-fit test showed a good fit (P>0.05). DCA results showed a high net benefit of clinical intervention in very preterm infants when the threshold probability was 10%-60% for the training cohort and 10%-70% for the validation cohort. CONCLUSIONS: A nomogram model for predicting the risk of death during hospitalization has been established and validated in very preterm infants, which can help clinicians predict the probability of death during hospitalization in these infants.

[Clinical features of very preterm infants with prelabor rupture of membranes and predictive factors for major adverse outcomes].

OBJECTIVE: To study the clinical features of very preterm infants with prelabor rupture of membranes (PROM) and predictive factors for early-onset sepsis (EOS) and death. METHODS: A retrospective analysis was performed for the clinical data of the very preterm infants with PROM (with a gestational age of < 32 weeks) who were admitted to the neonatal intensive care unit from January 2018 to May 2020. According to the time from membrane rupture to delivery, the infants were divided into four groups: < 18 hours (n=107), 18 hours to < 3 days (n=111), 3 days to < 14 days (n=144), and ≥ 14 days (n=37). According to the presence or absence of EOS, the infants were divided into EOS (n=42) and non-EOS groups (n=357). According to the survival state, the infants were divided into a survival group (n=359) and a death group (n=40). Clinical features were analyzed for very preterm infants with different times of PROM. A multivariate logistic regression analysis was used to investigate the predictive factors for EOS and death in very preterm infants with PROM. RESULTS: There was no significant difference in the incidence rates of major neonatal complications and mortality rate among the very preterm infants with different times of PROM (P > 0.05). Birth weight < 1 000 g (OR=4.353, P=0.042), grade Ⅲ amniotic fluid contamination (OR=4.132, P=0.032), and grade Ⅲ-Ⅳ respiratory distress syndrome (RDS) (OR=2.528, P=0.021) were predictive factors for EOS in very preterm infants with PROM. Lower birth weights (< 1 000 g or 1 000-1 499 g; OR=11.267 and 3.456 respectively; P=0.004 and 0.050 respectively), grade Ⅲ-Ⅳ RDS (OR=5.572, P < 0.001), and neonatal sepsis (OR=2.631, P=0.012) were predictive factors for death in very preterm infants with PROM. CONCLUSIONS: Prolonged PROM does not increase the incidence of neonatal complications and mortality in very preterm infants. Adverse outcomes of very preterm infants with PROM are mainly associated with lower birth weights, lung immaturity, and systemic infection.