Presentation of an experimental method to induce in vitro ("organ chambers") respiratory acidosis and its effect on vascular reactivity

PURPOSE: To create in vitro a model to generate acidosis by CO2 bubbling "organ chambers", which would be useful for researchers that aim to study the effects of acid-base disturbs on the endothelium-dependent vascular reactivity. METHODS: Eighteen male Wistar rats (230-280g) were housed, before the experiments, under standard laboratory conditions (12h light/dark cycle at 21°C), with free access to food and water. The protocol for promoting in vitro respiratory acidosis was carried out by bubbling increased concentrations of CO2. The target was to achieve an ideal way to decrease the pH gradually to a value of approximately 6.6.It was used, initially, a gas blender varying concentrations of the carbogenic mixture (95% O2 + 5% CO2) and pure CO2. RESULTS: 1) 100% CO2, pH variation very fast, pH minimum 6.0; 2) 90%CO2 pH variation bit slower, pH minimum6.31; 3) 70%CO2, pH variation slower, pH minimum 6.32; 4) 50% CO2, pH variation slower, pH minimum 6:42; 5) 40 %CO2, Adequate record, pH minimum 6.61, and; 6) 30 %CO2 could not reach values below pH minimum 7.03. Based on these data the gas mixture (O2 60% + CO2 40%) was adopted, CONCLUSION: This gas mixture (O2 60% + CO2 40%) was effective in inducing respiratory acidosis at a speed that made, possible the recording of isometric force. .

Tomografia computadorizada na intoxicaçäo por metanol: relato de caso / Computed tomography in methanol intoxication

Tivemos a oportunidade de acompanhar com exames de TC caso de intoxicaçäo por metanol. O paciente foi submetido ao exame no momento da internaçäo e após seis dias, pela persistência de quadro neurológico grave. Observou-se nesta última a presença de lesöes putaminais simétricas e da substância branca subcortical, apesar do tratamento adequado. A comprovaçäo tomográfica de lesöes cerebrais evidenciou efeito tóxico do metanol e pode orientar o prognóstico neurológico