RESUMO
A hot-wire anemometer was evaluated to determine its suitability for measurement of small tidal volumes. Used with a constant background flow of gas, the output of the hot-wire anemometer was linear and independent of respiratory frequency, temperature, and humidity. The change in output with CO2 concentration was negligible within the physiologic range. The use of a background flow eliminates the need for one-way valves, minimizes dead space, and maintains the flow velocity past the hot wire within its range of linear response.
Assuntos
Medidas de Volume Pulmonar/instrumentação , Ventilação Pulmonar , Volume de Ventilação Pulmonar/instrumentação , Animais , Dióxido de Carbono , Umidade , TemperaturaAssuntos
Punções , Diálise Renal , Derivação Arteriovenosa Cirúrgica , Criança , Feminino , Humanos , Masculino , AgulhasRESUMO
The objective was to reduce treatment time while the average concentration of all molecular sizes was maintained equal to that in a standard treatment. A nomogram based on the one-pool patient-dialyser system has been devised. The patient variables are presented in dimensionless forms, thus making on diagram suffice for all patients and all molecular sizes. Seven patients were first observed during a standard programme and later during an individually calculated short-time programme. The clinical parameters indicated equal treatment. The method was practical enough for clinical use.
