The invention belongs to the field of medical sciences and respiratory masks. It is a cardiopulmonary resuscitation device that delivers assisted ventilation via a foot- or compressor-controlled bellows mechanism. This device frees the use of the hand used to compress the conventional self-inflating Airway Mask Bag Unit (AMBU), so that the free hand can be used to fit the mask over the patient's face and reduce the mechanical fatigue generated by the manual compression of current mechanisms. The unit attaches to ventilation masks, can have a frequency meter and is compatible with accessories comprising conventional cardiopulmonary resuscitation devices; inside it has a valve that controls the filling of the oxygen reservoir and the time at which oxygen is released to be supplied to the patient.

A respiratory device includes a blower having an inlet and an outlet, a patient interface, and a valve including a valve member that is rotatable from a first position to a second position. The outlet of the blower is coupled to the patient interface so that positive pressure is provided to a patient's airway via the patient interface when the valve member is in the first position. The inlet of the blower is coupled to the patient interface so that negative pressure is provided to the patient's airway via the patient interface when the valve member is in the second position. The valve member is rotatably oscillated back and forth when the valve member is in the first position and when the valve member is in the second position so that oscillations in the positive pressure and negative pressure, respectively, are provided to the patient's airway.

A leak control system (26) for an evacuation system (12) of an insufflation system (1), for controlling leakage of insufflating gas from a vessel (5) of a subject being insufflated. An evacuation conduit (20) connects a Venturi vacuum creating device (14) to the vessel (5) through a pressure relief valve (27) operable from a closed state to an open state in response to a pressure drop across the pressure relief valve (27) in the direction of the arrow A exceeding a predefined pressure drop value. The vacuum creating device (14) is operable in response to a signal from a pressure sensor (10) detecting pressure in the cavity (5) exceeding a predefined pressure value for applying a vacuum to the evacuating conduit (20) to increase the pressure drop across the pressure relief valve (27) to the predefined pressure drop value, for in turn operating the pressure relief valve (27) into the open state. On the pressure in the vessel (5) being reduced below the predefined pressure value, the vacuum creating device (14) is deactivated, and the pressure relief valve (27) transitions into the closed state, thereby preventing further leakage of insufflating gas though the Venturi vacuum creating device (14).