Sildenafil in endotoxin-induced pulmonary hypertension: an experimental study.

BACKGROUND: Sepsis and septic shock still represent great challenges in critical care medicine. Sildenafil has been largely used in the treatment of pulmonary arterial hypertension, but its effects in sepsis are unknown. The aim of this study was to investigate the hypothesis that sildenafil can attenuate endotoxin-induced pulmonary hypertension in a porcine model of endotoxemia. METHODS: Twenty pigs were randomly assigned to Control group (n.ß=.ß10), which received saline solution; or to Sildenafil group (n.ß=.ß10), which received sildenafil orally (100.ßmg). After 30.ßminutes, both groups were submitted to endotoxemia with intravenous bacterial lipopolysaccharide endotoxin (LPS) infusion (4.ß..g.kg-1.h-1) for 180.ßminutes. We evaluated hemodynamic and oxygenation functions, and also lung histology and plasma cytokine (TNF.., IL-1.., IL6, and IL10) and troponin I response. RESULTS: Significant hemodynamic alterations were observed after 30.ßminutes of LPS continuous infusion, mainly in pulmonary arterial pressure (from Baseline 19.ß...ß2.ßmmHg to LPS30 52.ß...ß4.ßmmHg, p.ß<.ß0.05). There was also a significant decrease in PaO2/FiO2 (from Baseline 411.ß...ß29 to LPS180 334.ß...ß49, p.ß<.ß0.05). Pulmonary arterial pressure was significantly lower in the Sildenafil group (35.ß...ß4.ßmmHg at LPS30, p.ß<.ß0.05). The Sildenafil group also presented lower values of systemic arterial pressure. Sildenafil maintained oxygenation with higher PaO2/FiO2 and lower oxygen extraction rate than Control group but had no effect on intrapulmonary shunt. All cytokines and troponin increased after LPS infusion in both groups similarly. CONCLUSION: Sildenafil attenuated endotoxin-induced pulmonary hypertension preserving the correct heart function without improving lung lesions or inflammation.

Sildenafil in endotoxin-induced pulmonary hypertension: an experimental study

Abstract Background Sepsis and septic shock still represent great challenges in critical care medicine. Sildenafil has been largely used in the treatment of pulmonary arterial hypertension, but its effects in sepsis are unknown. The aim of this study was to investigate the hypothesis that sildenafil can attenuate endotoxin-induced pulmonary hypertension in a porcine model of endotoxemia. Methods Twenty pigs were randomly assigned to Control group (n = 10), which received saline solution; or to Sildenafil group (n = 10), which received sildenafil orally (100 mg). After 30 minutes, both groups were submitted to endotoxemia with intravenous bacterial lipopolysaccharide endotoxin (LPS) infusion (4 µg.kg-1.h-1) for 180 minutes. We evaluated hemodynamic and oxygenation functions, and also lung histology and plasma cytokine (TNFα, IL-1β, IL6, and IL10) and troponin I response. Results Significant hemodynamic alterations were observed after 30 minutes of LPS continuous infusion, mainly in pulmonary arterial pressure (from Baseline 19 ± 2 mmHg to LPS30 52 ± 4 mmHg, p< 0.05). There was also a significant decrease in PaO2/FiO2 (from Baseline 411 ± 29 to LPS180 334 ± 49, p< 0.05). Pulmonary arterial pressure was significantly lower in the Sildenafil group (35 ± 4 mmHg at LPS30, p< 0.05). The Sildenafil group also presented lower values of systemic arterial pressure. Sildenafil maintained oxygenation with higher PaO2/FiO2 and lower oxygen extraction rate than Control group but had no effect on intrapulmonary shunt. All cytokines and troponin increased after LPS infusion in both groups similarly. Conclusion Sildenafil attenuated endotoxin-induced pulmonary hypertension preserving the correct heart function without improving lung lesions or inflammation.

The COVID-19 pandemic's impact on the practices and biosecurity measures of veterinary medicine professionals in Brazil.

Veterinarians, among other health professionals, are considered health professionals at high risk of exposure to and contraction of COVID-19. The main objective of this study is to assess changes in the clinical practices of veterinarians during the COVID-19 pandemic around prophylactic and biosafety measures, as well as to evaluate changes in workload and cost-benefit ratio. An online questionnaire was sent to veterinary professionals from July 2020 to July 2021 using Google Forms. A total of 1134 veterinarians answered the questionnaire on clinical experiences and biosafety practices during the COVID-19 pandemic. Veterinarians changed their routine clinical practices, as there was a reduction in working hours, and applied new patient approaches and advice to their owners, as well as restricting the number of people allowed inside. Biosafety measures were added in their workplaces, with an increase in the use of personal protective equipment. COVID-19 tests were administered at least once in 19.0%, and more than once in 9.5% of the respondents. Flu symptoms were present in 23.8% of the respondents, and 31.0% of the veterinarians attended to COVID-19 positive pet owners. Therefore, most veterinarians altered their routine practices, and some were exposed to sources of COVID-19 infection.

Os médicos veterinários, entre outros profissionais de saúde, são considerados profissionais de saúde sob alto risco de exposição e contração do COVID-19. O objetivo principal do presente estudo foi avaliar as mudanças na prática clínica de médicos veterinários durante a pandemia de COVID-19 em torno das medidas profiláticas e de biossegurança, assim como avaliar as mudanças na carga de trabalho e a relação custo-benefício. De julho a dezembro de 2020, um questionário online foi enviado aos profissionais por meio da ferramenta Formulários Google. Um total de 1.134 veterinários responderam ao questionário relacionado às experiências clínicas e práticas de biossegurança durante a pandemia COVID-19. Os médicos veterinários mudaram suas práticas clínicas rotineiras, pois houve redução da jornada de trabalho, novas abordagens dos pacientes e orientações aos proprietários, além da restrição do número de pessoas nos locais. Medidas de biossegurança foram adicionadas aos locais de trabalho, com aumento do uso de equipamentos de proteção individual. Os testes COVID-19 foram realizados pelo menos uma vez em 19,0% e mais de uma vez em 9,5% dos entrevistados. Sintomas de gripe estavam presentes em 23,8% dos profissionais entrevistados e 31,0% dos veterinários atendiam tratadores de animais positivos para COVID-19. Portanto, a maioria dos veterinários alterou suas práticas de rotina e alguns foram expostos a fontes de infecção COVID-19.

Efeitos do sildenafil em modelo experimental de endotoxemia em suínos / Effects of sildenafil in experimental model of endotoxemia in pigs

INTRODUÇÃO: Apesar de todos os esforços, as taxas de mortalidade no choque séptico ainda são altas, e entre as diversas complicações deste quadro, a hipertensão pulmonar é considerada um fator agravante. O sildenafil é um fármaco com efeito vasodilatador arterial pulmonar que atua através da inibição da fosfodiesterase 5, aumentando o GMPcíclico e promovendo relaxamento da musculatura lisa. OBJETIVO: Avaliar se a administração de sildenafil atenua as alterações hemodinâmicas ocasionadas pelo choque endotoxêmico, bem como os parâmetros de ventilação e oxigenação em modelo experimental de endotoxemia em suínos. MÉTODOS: Foram utilizados 20 suínos nos quais o choque endotoxêmico foi induzido através da infusão intravenosa de LPS (4ug/kg/h). Os animais foram randomizados e alocados da seguinte maneira: Controle (CTL, n=10) - submetidos apenas ao choque endotoxêmico; Sildenafil (SIL, n=10) - tratados com sildenafil na dose de 100 mg por via oral antes de serem submetidos ao choque endotoxêmico. Foram avaliados os parâmetros hemodinâmicos, ventilatórios, e de oxigenação, a partir do momento Basal até 180 minutos da infusão de LPS. Os efeitos inflamatórios e de lesão miocárdica também foram avaliados, bem como a análise histopatológica do tecido pulmonar. Os dados paramétricos foram analisados utilizando ANOVA de duas vias para medidas repetidas, seguidas por Tukey quando necessário, enquanto para os dados não paramétricos utilizou-se o teste de Mann-Whitney. RESULTADOS: A endotoxemia induziu hipertensão pulmonar com aumento significativo na pressão arterial pulmonar e no índice de resistência vascular pulmonar, e também diminuição na PaO2 / FiO2. A pressão arterial pulmonar e sistêmica foram significativamente menores no grupo Sildenafil, sendo que o os valores máximos de PAPM observados aos 30 minutos de infusão de LPS foram 35 e 52 mmHg, nos grupos Sildenafil e Controle, respectivamente. O Sildenafil manteve a oxigenação, através de maior...

INTRODUCTION: Despite all efforts, mortality rates in septic shock are still high, and among the various complications pulmonary hypertension is considered a poor prognostic factor. Sildenafil is a drug with pulmonary arterial vasodilator effect, acts through inhibition of phosphodiesterase V that increases GMPc promoting the vasodilator effect. OBJECTIVE: Evaluate if sildenafil attenuates hemodynamic changes caused by septic shock, as well as ventilation and oxygenation parameters in an experimental model of endotoxemia in pigs. METHODS: Twenty pigs in which endotoxemia was induced through intravenous LPS infusion (4ug/kg/h) were randomly assigned to Control group (CTL, n = 10) - which received saline solution previous the endotoxemia; or to Sildenafil group (SIL, n = 10) - which received sildenafil orally (100 mg) previous the endotoxemia. Hemodynamic, ventilation and oxygenation were evaluated from at baseline up to 180 minutes of LPS infusion. The inflammatory and myocardial damage effects were also evaluated. Lung tissue was collected for histological analysis. Parametric data were compared using two-way repeated measures ANOVA, followed by Tukey test when necessary, while for non-parametric data the Mann-Whitney test was used. RESULTS: Endotoxemia induced pulmonary hypertension with an increase in pulmonary arterial pressure and pulmonary vascular resistance index and also a decrease in PaO2/FiO2. Pulmonary and systemic arterial pressures were significantly lower in the Sildenafil group, wherein the PAPM maximum values observed at 30 minutes of LPS infusion were 35 and 52 mmHg in the sildenafil and control groups, respectively. Sildenafil maintained oxygenation with superior PaO2/FiO2 and higher SvO2, but had no effect on intrapulmonary shunt. All cytokines and troponin increased after LPS infusion and there was no significant intergroup difference. Sildenafil did not attenuate the histologic alterations from endotoxemic shock. CONCLUSION: Sildenafil...