[Analysis of risk factors of mortality in infants and toddlers with moderate to severe pediatric acute respiratory distress syndrome]

Objective: To identify the risk factors in mortality of pediatric acute respiratory distress syndrome (PARDS) in pediatric intensive care unit (PICU). Methods: Second analysis of the data collected in the "efficacy of pulmonary surfactant (PS) in the treatment of children with moderate to severe PARDS" program. Retrospective case summary of the risk factors of mortality of children with moderate to severe PARDS who admitted in 14 participating tertiary PICU between December 2016 to December 2021. Differences in general condition, underlying diseases, oxygenation index, and mechanical ventilation were compared after the group was divided by survival at PICU discharge. When comparing between groups, the Mann-Whitney U test was used for measurement data, and the chi-square test was used for counting data. Receiver Operating Characteristic (ROC) curves were used to assess the accuracy of oxygen index (OI) in predicting mortality. Multivariate Logistic regression analysis was used to identify the risk factors for mortality. Results: Among 101 children with moderate to severe PARDS, 63 (62.4%) were males, 38 (37.6%) were females, aged (12±8) months. There were 23 cases in the non-survival group and 78 cases in the survival group. The combined rates of underlying diseases (52.2% (12/23) vs. 29.5% (23/78), χ²=4.04, P=0.045) and immune deficiency (30.4% (7/23) vs. 11.5% (9/78), χ²=4.76, P=0.029) in non-survival patients were significantly higher than those in survival patients, while the use of pulmonary surfactant (PS) was significantly lower (8.7% (2/23) vs. 41.0% (32/78), χ²=8.31, P=0.004). No significant differences existed in age, sex, pediatric critical illness score, etiology of PARDS, mechanical ventilation mode and fluid balance within 72 h (all P>0.05). OI on the first day (11.9(8.3, 17.1) vs.15.5(11.7, 23.0)), the second day (10.1(7.6, 16.6) vs.14.8(9.3, 26.2)) and the third day (9.2(6.6, 16.6) vs. 16.7(11.2, 31.4)) after PARDS identified were all higher in non-survival group compared to survival group (Z=-2.70, -2.52, -3.79 respectively, all P<0.05), and the improvement of OI in non-survival group was worse (0.03(-0.32, 0.31) vs. 0.32(-0.02, 0.56), Z=-2.49, P=0.013). ROC curve analysis showed that the OI on the thind day was more appropriate in predicting in-hospital mortality (area under the curve= 0.76, standard error 0.05,95%CI 0.65-0.87,P<0.001). When OI was set at 11.1, the sensitivity was 78.3% (95%CI 58.1%-90.3%), and the specificity was 60.3% (95%CI 49.2%-70.4%). Multivariate Logistic regression analysis showed that after adjusting for age, sex, pediatric critical illness score and fluid load within 72 h, no use of PS (OR=11.26, 95%CI 2.19-57.95, P=0.004), OI value on the third day (OR=7.93, 95%CI 1.51-41.69, P=0.014), and companied with immunodeficiency (OR=4.72, 95%CI 1.17-19.02, P=0.029) were independent risk factors for mortality in children with PARDS. Conclusions: The mortality of patients with moderate to severe PARDS is high, and immunodeficiency, no use of PS and OI on the third day after PARDS identified are the independent risk factors related to mortality. The OI on the third day after PARDS identified could be used to predict mortality.

[Effect of valsartan on the expression of leptin, leptin receptor and collagen in rats with hepatic fibrosis]

Objective: To investigate the effects of angiotensin II type 1 receptor antagonist valsartan on leptin, leptin receptor and collagen in rats with hepatic fibrosis. Methods: Thirty-six male wistar rats were randomly divided into control group, model group and drug-treated group, with 12 rats in each group. Liver fibrosis models were made by subcutaneous injection of carbon tetrachloride on the dorsal of the rats, simultaneously gastric gavage with Valsartan and were killed at the end of 8th week. The degree of liver fibrosis was observed by HE and Masson staining. The serum leptin (LP) and TGFβ1 were determined by ELISA. Liver LP mRNA and leptin receptor mRNA (OB-R mRNA) were detected by RT-PCR. Liver LP, OB-R and collagen I were detected by Western blot. The data of multiple groups were analyzed by one-way analysis variance (ANOVA), and linear correlation was performed between serum LP and TGF β1. Results: After the intervention of valsartan, HE and Masson staining showed that the degree of liver fibrosis was significantly reduced. The levels of serum LP and TGFβ1 in the control group were (18.92 ± 7.10) ng/ml and (9.13 ± 1.58) pg/ml respectively, which were significantly lower than those in the model group (46.92 ± 28.54) ng/ml and (16.39 ± 3.56) pg/ml, And (29.27 ± 7.27) ng/ml and (12.24 ± 2.94) pg/ml in the drug-treated group, respectively. The F values were 7.864 and 20.057 respectively. The P values were < 0.05. The differences were statistically significant. The relative expression levels of LP and OB-R mRNA in the control group were 0.35 ± 0.18 and 0.62 ± 0.18, respectively, which were significantly lower than those in the model group (1.79 ± 1.79 and 1.52 ± 1.44, and drug-treated group 0.48 ± 0.34 and 0.75 ± 0.26, respectively), F values = 6.914,3.894, P values were < 0.05, the differences were statistically significant. The relative expression levels of LP, OB-R and collaten I in liver were 0.71 ± 0.13, 0.81 ± 0.11 and 0.76 ± 0.13 in the model group, 0.97 ± 0.06, 1.04 ± 0.06, and 1.05 ± 0.04 respectively in the drug-treated group and 0.74 ± 0.05, 0.93 ± 0.05 and 0.91 ± 0.05. The F values were 15.425, 13.757 and 19.130 respectively in three groups (P < 0.001), the difference was statistically significant. Conclusion: Valsartan, an angiotensin II type 1 receptor antagonist, can reduce the expression of leptin and leptin receptor, reduce the production of TGFβ1 and collaten I, and play an anti-hepatic fibrosis effect.