Abstract: An isolation valve for use in administering mouth-to-mouth emergency artificial respiration includes a housing having a fixed inlet pipe and a rotatable outlet pipe, a bacteria filter permanently secured in the housing member around the periphery of the filter whereby all of the gas passing through the device must pass through the filter, and a one-way valve seated in the housing and cooperating with valve seats for opening and closing exhaust ports.

Abstract: An improved apparatus for monitoring a respiratory circuit comprises two independent pressure sensing means, a first pressure sensing component having a preset minimum pressure for creating an alarm condition in response to pressure falling below the minimum, and a second pressure sensing component having an adjustable low pressure threshold setting means and for creating an alarm condition if the patient's breathing cycle pressure fails to periodically pass through the low threshold pressure. A preferred embodiment includes visual pressure indicating means including a display of the low threshold pressure setting and a display of the patient's breathing cycle pressures.