Vascular and ventilatory mechanical responses in three different stages of pulmonary development in the rabbit model of congenital diaphragmatic hernia

Abstract Purpose: To evaluate the vascular ventilatory response in different stages of lung development and to compare them to the neonates with congenital diaphragmatic hernia (CDH) in a rabbit model. Methods: New Zealand rabbits were divided into 8 groups (n=5): E25, E27, E30, and CDH. All groups were ventilated on a FlexiVent (Scireq, Montreal, QC, Canada), compounding the other 4 groups. The CDH surgery was performed at E25 and the harvest at E30. Dynamic compliance (CRS), dynamic elastance (ERS) and dynamic resistance (RRS) were measured every 4 min/24 min. Median wall thickness (MWT) and airspace were measured. ANOVA Bonferroni tests were used to perform statistical analysis. Significance was considered when p<0.05. Results: CRS was higher in E30 compared to all other groups (p<0.05). CRS and RRS of CDH and E27 were similar and were higher in E25 (p<0.05). MWT was decreased according to the gestational age, was increased in E27V and E30V (p<0.05) and decreased in CDHV (p<0.05), airspace was decreased in E25 and increased in all ventilated groups (p<0.05). Conclusions: The ventilation response of congenital diaphragmatic hernia is like the pseudoglandular stage of the lung development. These findings add information about the physiology of pulmonary ventilation in CDH.

Frequência de retinopatia da prematuridade em recém-nascidos no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo / Frequency of retinopathy of prematurity at newborns at the Clinical Hospital, Ribeirão Preto Medical School, University of São Paulo

OBJETIVOS: Determinar a frequência de retinopatia da prematuridade no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto (HCFMRP-USP) e verificar a associação da retinopatia da prematuridade com fatores de risco conhecidos. MÉTODOS: Foi realizada análise prospectiva de 70 pacientes, nascidos no HCFMRP-USP, com peso inferior a 1.500 gramas, no período de um ano. Os pacientes foram divididos em dois grupos (Retinopatia da prematuridade e Normal) para realização de análise estatística com relação a fatores de risco conhecidos. Adotou-se nível de significância de 5 por cento. RESULTADOS: A frequência de retinopatia da prematuridade foi de 35,71 por cento entre os pré-termos estudados. Os fatores pesquisados que apresentaram relação de risco para o desenvolvimento da doença foram: peso (p=0,001), idade gestacional (p=0,001), escore SNAPPE II (p=0,008), uso de oxigenoterapia por intubação (p=0,019) e por pressão positiva de vias aéreas (p=0,0017), múltiplas transfusões sanguíneas (p=0,01) e uso de diuréticos (p=0,01). CONCLUSÃO: A frequência de retinopatia da prematuridade foi de 35,71 por cento entre os prétermos nascidos com menos de 1.500 g. Vários fatores de risco foram identificados nos recém-nascidos do HCFMRP-USP, sendo constatado que crianças mais pré-termos apresentam formas mais graves de retinopatia da prematuridade.

PURPOSE: To determine the frequency of retinopathy of prematurity at the Clinical Hospital of Ribeirão Preto Medical School (HCFMRP-USP) and verify the association of retinopathy of prematurity with known risk factors. METHODS: Prospective analysis of 70 patients born in the HCFMRP-USP, weighing less than 1,500 grams, in a period of 1 year. The patients were divided into 2 groups (Retinopathy of prematurity and Normal) to verify the association of retinopathy of prematurity and known risk factors. Significance level of 5 percent was used. RESULTS: The frequency of retinopathy of prematurity was 35.71 percent among the study population. The studied risk factors significantly related to the development of the disease were: weight (p=0.001), gestational age (p=0.001), score SNAPPE II (p=0.008), use of oxygen by intubation (p=0.019) and continuous positive airway pressure (p=0.0017), multiple blood transfusions (p=0.01), and the use of diuretics (p=0.01). CONCLUSION: The frequency of retinopathy of prematurity was 35.71 percent and several risk factors have been identified in newborns in the HCFMRP-USP, being evidenced that the more preterm, the more severe retinopathy of prematurity is likely to be.