Initial respiratory support modality and outcome in preterm infants with less than 32 weeks of gestation in China: A multicentre retrospective cohort study.

BACKGROUND: For initial respiratory management, continuous positive airway pressure (CPAP) is increasingly used for preterm infants, especially for gestational age less than 32 weeks. However, neonatologists are concerned about the potential risks of CPAP support failure. OBJECTIVES: To examine the association between different initial respiratory support modalities and the outcomes of preterm infants at <32 weeks of gestation across multiple neonatal intensive care units (NICU) in China. METHODS: This study was carried out over a period of 12 months in 2018. Unadjusted relative risks (RR) for demographic and clinical characteristics were calculated for CPAP failure and CPAP success in the total cohort using log-linear model based on generalised estimating equations for clustered observations. RESULTS: Among 1560 preterm infants delivered at <32 weeks, the incidence of CPAP failure was 10.3%. After adjustment for demographic and clinical factors, the relative risk of mortality (RR 7.54, 95% CI 5.56, 10.44), pneumothorax (RR 9.85, 95% CI 2.89, 61.53), pulmonary haemorrhage (RR 7.78, 95% CI 4.51, 14.64) and BPD (RR 3.65, 95% CI 3.65, 4.51) were considerably higher for infants in the CPAP failure group than those in the CPAP-S group. However, the risk of poor outcomes in CPAP failure infants was similar to that of those in the initial mechanical ventilation (MV) group. CONCLUSIONS: Continuous positive airway pressure failure was associated with an increased risk of mortality and major morbidities, including BPD, pulmonary haemorrhage and pneumothorax, and was comparable to the risk associated with initial MV.

Association between admission hypothermia and outcomes in very low birth weight infants in China: a multicentre prospective study.

BACKGROUND: The objective of this prospective, multicentre, observational cohort study was to evaluate the association between admission hypothermia and neonatal outcomes in very low-birth weight (VLBW) infants in multiple neonatal intensive care units (NICUs) in China. METHODS: Since January 1, 2018, a neonatal homogeneous cooperative research platform-Shandong Neonatal Network (SNN) has been established. The platform collects clinical data in a prospective manner on preterm infants with birth weights (BWs) < 1500 g and gestational ages (GAs) < 34 weeks born in 28 NICUs in Shandong Province. These infants were divided into normothermia, mild or moderate/severe hypothermia groups according to the World Health Organization (WHO) classifications of hypothermia. Associations between outcomes and hypothermia were tested in a bivariate analysis, followed by a logistic regression analysis. RESULTS: A total of 1247 VLBW infants were included in this analysis, of which 1100 infants (88.2%) were included in the hypothermia group, 554 infants (44.4%) in the mild hypothermia group and 546 infants (43.8%) in the moderate/severe hypothermia group. Small for gestational age (SGA), caesarean section, a low Apgar score at 5 min and intubation in the delivery room (DR) were related to admission hypothermia (AH). Mortality was the lowest when their admission temperature was 36.5 ~ 37.5 °C, and after adjustment for maternal and infant characteristics, mortality was significantly associated with AH. Compared with infants with normothermia (36.5 ~ 37.5 °C), the adjusted ORs of all deaths increased to 4.148 (95% CI 1.505-11.437) and 1.806 (95% CI 0.651-5.009) for infants with moderate/severe hypothermia and mild hypothermia, respectively. AH was also associated with a high likelihood of respiratory distress syndrome (RDS), intraventricular haemorrhage (IVH), and late-onset neonatal sepsis (LOS). CONCLUSIONS: AH is still very high in VLBW infants in NICUs in China. SGA, caesarean section, a low Apgar score at 5 min and intubation in the DR were associated with increased odds of hypothermia. Moderate/severe hypothermia was associated with mortality and poor outcomes, such as RDS, IVH, LOS.

[Hyperoxia-induced retinal peroxidative injury in immature rats].

OBJECTIVE: To investigate the role of oxidative stress in the pathogenesis of retinal injury induced by hyperoxia. METHODS: Sixty immature Sprague-Dawley (SD) rats born at a gestational age of 21 days, were randomly exposed to room air (air group, n=30) or 95% oxygen (hyperoxia group, n=30) immediately after birth. Plasma 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) levels were determined by ELISA. The ultrastructures of the retina were observed under a transmission electron microscope. RESULTS: The plasma 8-iso-PGF2alpha contents of the air group were 19.09 +/-5.57, 18.24+/-5.91 and 17.00 +/- 5.58 pg/mL on the 3rd, 7th and 14th days after birth, respectively (F=1.024, P> 0.05). The plasma 8-iso-PGF2 contents in the hyperoxia group on the 3rd (28.33 +/- 5.59 pg/mL), the 7th day (51.20 +/- 15.01 pg/mL) and 14th day (84.54 +/- 14.85 pg/mL) after birth were significantly higher than those of the air group (t=2.863, P< 0.05; t=5.073, P< 0.01; t=11.006, P< 0.01). Moreover, the plasma 8-iso-PGF2 contents in the hyperoxia group increased with the prolonged hyperoxia exposure (F=150.7, P < 0.01). The ultrastructures of retina in the air group were normal. Hyperoxia exposure resulted in abnormalities of the ultrastructures of retina, manifesting as the membrane discs rarefied, twisted and disrupted and mitochondrial swelling. CONCLUSIONS: Oxidative stress can results in retinal injury in immature rats. An increased plasma level of 8-iso-PGF2alpha is related to the injury degree of retina.

Retinoic acid promotes primary fetal alveolar epithelial type II cell proliferation and differentiation to alveolar epithelial type I cells.

Retinoic acid (RA) plays an important role in lung development and maturation. Many stimuli can induce alveolar epithelial cell damage which will result in the injury of lung parenchyma. The aim of this study was to observe the effect of RA on the proliferation and differentiation of primary fetal alveolar epithelial type II cells (fAECIIs). Primary fAECIIs were isolated from fetal rats at 19 d of gestation and purified by a differential centrifugation and adhesion method. The cells were randomly divided into control (dimethyl sulfoxide, DMSO) and RA groups. Cell proliferation, viability, apoptosis, cycle, and expression of target protein were examined at 24, 48, and 72 h. We found that the proliferation and viability of cells in the RA-exposed group significantly increased compared with the DMSO control group. The proportion (%) of cells in the G2 and S phases in the RA group was significantly higher than that in control group cells. The proportion (%) of both early apoptotic cells and late apoptotic cells decreased significantly in cells exposed to RA compared with cells exposed to DMSO. RA significantly enhanced the expression of aquaporin 5 (AQP5). The expression level of pulmonary surfactant C (SPC) was elevated after cells were exposed to RA for 24 and 72 h but was inhibited when cells were exposed to RA for 48 h. These results suggest that RA promotes fAECII proliferation by improving cell viability, promoting S phase entry and inhibiting apoptosis and RA promotes fAECIIs differentiation to alveolar epithelial type I cells (AECIs).

Low-dose heparin as treatment for early disseminated intravascular coagulation during sepsis: A prospective clinical study.

The present study aimed to investigate whether low-dose heparin improves the condition of patients suffering from early disseminated intravascular coagulation (pre-DIC) during sepsis. In total, 37 patients were randomly divided into low-dose heparin intervention and control groups. The heparin group received a low-dose of heparin for 5-7 days, while the other group received only saline. The two groups were treated for sepsis. Blood samples were collected at various times and acute physiology and chronic health evaluation (APACHE)-II scores were recorded at day 1 and 7. In addition, the number of days applying mechanical ventilation and in the intensive care unit (ICU) were recorded, as well as the 28-day mortality rate. APACHE-II scores in the two groups decreased following treatment, however, scores in the heparin group decreased more significantly. Prothrombin fragment and thrombin-antithrombin complex levels in the heparin group were significantly decreased. In addition, the number of days applying a ventilator was fewer and the total stay in ICU was significantly shorter compared with the control group. Significantly fewer complications were observed in the heparin group, however, there was no significant difference in the 28-day mortality rate. In conclusion, low-dose heparin improves the hypercoagulable state of sepsis, which subsequently reduces the incidence of DIC or multiple organ dysfunction syndrome, decreasing the number of days of mechanical ventilation and hospitalization.

Improved outcomes of transported neonates in Beijing: the impact of strategic changes in perinatal and regional neonatal transport network services.

BACKGROUND: Infants born outside perinatal centers may have compromised outcomes due to the transfer speed and efficiency to an appropriate tertiary center. This study aimed to evaluate the impact of regional coordinated changes in perinatal supports and retrieval services on the outcome of transported neonates in Beijing, China. METHODS: Information about transported newborns between phase 1 (July 1, 2004 to June 30, 2006) and phase 2 (July 1, 2007 to June 30, 2009) was collected. The strategic changes during phase 2 included standardized neonatal transport procedures, skilled attendants, a perinatal consulting service, and preferential admission of transported neonates to the intensive care unit of the tertiary care center. Data from phase 2 (after-strategic changes) were compared with those of phase 1 (the period of pre-strategic changes) after a 12-month washout period, especially regarding the reduction in mortality and selected morbidity. RESULTS: There was a large increase in the number of transported infants in phase 2 compared with phase 1 (2797 vs. 567 patients). The average monthly rate of increase of transported infants was 383.3% (from 24 infants per month to 116 infants per month). The mortality rate of transported neonates reduced significantly from phase 1 to phase 2 (5.11% vs. 2.82%; P=0.005), particularly for preterm infants (8.47% vs. 4.34%; P=0.006). In addition, transported neonates during phase 2 had significantly decreased morbidities. CONCLUSIONS: Regional coordinated strategies optimizing the perinatal services and transport of outborn sick and preterm infants to tertiary care centers improved survival outcomes considerably. These findings have vital implications for health outcomes and resource planning.

Effect of hyperoxia on the viability and proliferation of the primary type II alveolar epithelial cells.

To observe the effect of hyperoxia on the growth of type II alveolar epithelial cells (AEC II). The lungs of 19-day gestation fetal rats were primary cultured and the AEC II were purified by differential adhesion method. The cells were divided into control (normoxia) group and hyperoxia group. The cell growth, cell viability, cell apoptosis, and cell cycle were examined at 2, 4, 6, and 8 days of normoxia or hyperoxia exposure. The number of cells in hyperoxia-exposed group significantly decreased as compared to those of air control group. Number of cells in hyperoxia group was the highest at day 2 of exposure and gradually decreased with time. The viability of cells exposed to hyperoxia was substantially reduced compared with cells exposed to air. Percentage of cells in G1 phase and S phase in hyperoxia group increased gradually with increase in exposure duration and significant differences were seen at day 4 and day 6 compared with either the preceding time points and also with corresponding air-exposed cells. The percentage of both early apoptotic cells (Annexin-V(+)/PI(-)) and late apoptotic cells and necrotic cells (Annexin-V(+)/PI(+)) increased significantly in cells exposed to hyperoxia compared with cells exposed to air. Hyperoxia inhibits proliferation, viability and growth of AEC II and promotes apoptosis.

Correlation study of 3T-MR-DTI measurements and clinical symptoms of cervical spondylotic myelopathy.

OBJECTIVE: To discuss the correlation between diffusion tensor imaging (DTI) measurements, diffusion tensor tractography and the clinical symptoms of cervical spondylotic myelopathy. METHODS: Based on the Japanese Orthopedics Association (JOA) score, 104 cervical spondylotic myelopathy cases were first divided into four groups: mild, moderate, severe and serious groups. According to lesion signal characteristics, all cases were again divided into three groups: A(N/N): normal signal in both T1WI and T2WI; B (N/H): normal signal in T1WI but high signal in T2WI; and C (L/H): low signal in T1WI and high signal in T2WI. The apparent diffusion coefficient (ADC), fractional anisotropy (FA), λ1, λ2, and λ3 were measured and diffusion tensor tractography was performed in the seriously compressed section of the spinal cord. RESULTS: The FA values were positively correlated with JOA scores (r=0.883, P<0.05), and significantly different among four JOA groups (P<0.05). The ADC, λ2, and λ3 were significantly different among the moderate, severe and serious groups as well as among the A, B, and C groups (P<0.05). Declining FA values were found associated with increasing fiber bundle damage. CONCLUSIONS: The FA values and the change patterns of fiber bundle were more sensitive than T2WI for spinal cord lesion, and were positively correlated with clinical symptoms.