Apparatus for assisting ventilation including reduced exhalation pressure mode

Claim 1

An apparatus for assisting with the ventilation of a patient breathing in successive cycles, each of the cycles including an inhalation phase and an exhalation phase, said apparatus being of the type including an inhalation assistance mode, triggered by the patient during the beginning of the inhalation phase, which causes said apparatus to deliver to the patient a flowrate of gas under a pressure equal to a given reference value, said apparatus comprising: a source of pressurized gas, said source including an outlet orifice which delivers a flowrate of pressurized gas; a face mask for placing over the upper airways of a patient, whereby said face mask enables the patient to receive said flowrate of pressurized gas delivered from said outlet orifice of said source; and a transmission circuit for coupling said source to said said face mask, said transmission circuit including: a main inhalation conduit coupled between said outlet orifice of said source of pressurized gas and said face mask; a discharge orifice; a secondary exhalation conduit for communicating with said face mask, said secondary exhalation conduit being coupled between said main inhalation conduit and said discharge orifice; a flow regulating valve interposed in said main inhalation conduit, said flow regulating valve including means for maintaining a residual flowrate of gas substantially equal to a pressure of 1 mbar in said main inhalation conduit during the exhalation phase of each of the breathing cycles of the patient; an exhalation valve interposed in said secondary exhalation conduit; and an operating circuit coupled to said flow regulating valve and said exhalation valve, said circuit operating said flow regulating valve based on the flowrate and pressure of said gas in said main inhalation conduit as measured downstream past said flow regulating valve in order to determine the beginning the inhalation phase of each of the breathing cycles of the patient, and said circuit causing said exhalation valve to open during the exhalation phase of each of the breathing cycles of the patient.

Claim 2

An apparatus for assisting with the ventilation of a patient breathing in successive cycles, each of the cycles including an inhalation phase and an exhalation phase, said apparatus being of the type including an inhalation assistance mode, triggered by the patient during the beginning of the inhalation phase, which causes said apparatus to deliver to the patient a flowrate of gas under a pressure equal to a given reference value, said apparatus comprising: a source of pressurized gas, said source including an outlet orifice which delivers a flowrate of pressurized gas; a face mask for placing over the upper airways of a patient, whereby said face mask enables the patient to receive said flowrate of pressurized gas delivered from said outlet orifice of said source; and a transmission circuit for coupling said source to said said face mask, said transmission circuit including: a main inhalation conduit coupled between said outlet orifice of said source of pressurized gas and said face mask; a discharge orifice; a secondary exhalation conduit for communicating with said face mask, said secondary exhalation conduit being coupled between said main inhalation conduit and said discharge orifice; a flow regulating valve interposed in said main inhalation conduit, said flow regulating valve including means for maintaining a residual flowrate of gas substantially equal to a pressure of 1 mbar in said main inhalation conduit during the exhalation phase of each of the breathing cycles of the patient; an exhalation valve interposed in said secondary exhalation conduit; and an operating circuit coupled to said flow regulating valve and said exhalation valve, said circuit operating said flow regulating valve based on the flowrate and pressure of said gas in said main inhalation conduit as measured downstream past said flow regulating valve in order to determine the beginning the inhalation phase of each of the breathing cycles of the patient, and said circuit causing said exhalation valve to open during the exhalation phase of each of the breathing cycles of the patient.

Claim 16

An apparatus for assisting with the ventilation of a patient breathing in successive cycles, each of the cycles including an inhalation phase and an exhalation phase, said apparatus being of the type including an inhalation assistance mode, triggered by the patient during the beginning of the inhalation phase, which causes said apparatus to deliver to the patient a flowrate of gas under a pressure equal to a given reference value, said apparatus comprising: a source of pressurized gas, said source including an outlet orifice which delivers a flowrate of pressurized gas; a face mask for placing over the upper airways of a patient, whereby said face mask enables the patient to receive said flowrate of pressurized gas delivered from said outlet orifice of said source; and a transmission circuit for coupling said source to said said face mask, said transmission circuit including: a main inhalation conduit coupled between said outlet orifice of said source of pressurized gas and said face mask; a discharge orifice; a secondary exhalation conduit for communicating with said face mask, said secondary exhalation conduit being coupled between said main inhalation conduit and said discharge orifice; a flow regulating valve interposed in said main inhalation conduit, for maintaining a residual flowrate of gas under a pressure of approximately zero in said main inhalation conduit during the exhalation phase of each of the breathing cycles of the patient, said flow regulating valve including a valve body which defines a regulating chamber, a first orifice selectively communicating with said regulating chamber to supply the pressurized gas thereto, a second orifice selectively communicating with said regulating chamber for delivering the pressurized gas in said regulating chamber to said main inhalation conduit, an axial tubular baffle which reduces and shifts the noise spectrum resulting from the flow of gas towards the high frequencies, a third orifice selectively communicating with said regulating chamber for venting ambient air, a moving member, a main check valve coupled to said moving member, and a secondary check valve coupled to said moving member, said moving member causing said main check valve to move from a first position which closes said third orifice to a second position which fully opens said third orifice and enables ambient air to be vented therethrough, wherein said secondary check valve is moved to a position which partially closes said second orifice when said main check valve is moved to said second position, in order to determine said residual flow rate under said pressure close to zero (0); an exhalation valve interposed in said secondary exhalation conduit; and an operating circuit coupled to said flow regulating valve and said exhalation valve, said circuit operating said flow regulating valve based on the flowrate and pressure of said gas in said main inhalation conduit as measured downstream past said flow regulating valve in order to determine the beginning the inhalation phase of each of the breathing cycles of the patient, and said circuit causing said exhalation valve to open during the exhalation phase of each of the breathing cycles of the patient.

Claim 17

An apparatus for assisting with the ventilation of a patient breathing in successive cycles, each of the cycles including an inhalation phase and an exhalation phase, said apparatus being of the type including an inhalation assistance mode, triggered by the patient during the beginning of the inhalation phase, which causes said apparatus to deliver to the patient a flowrate of gas under a pressure equal to a given reference value, said apparatus comprising: a source of pressurized gas, said source including an outlet orifice which delivers a flowrate of pressurized gas; a face mask for placing over the upper airways of a patient, whereby said face mask enables the patient to receive said flowrate of pressurized gas delivered from said outlet orifice of said source; and a transmission circuit for coupling said source to said said face mask, said transmission circuit including: a main inhalation conduit coupled between said outlet orifice of said source of pressurized gas and said face mask; a discharge orifice; a secondary exhalation conduit for communicating with said face mask, said secondary exhalation conduit being coupled between said main inhalation conduit and said discharge orifice; a flow regulating valve interposed in said main inhalation conduit, for maintaining a residual flowrate of gas under a pressure of approximately zero in said main inhalation conduit during the exhalation phase of each of the breathing cycles of the patient, said flow regulating valve including a valve body which defines a regulating chamber, a first orifice selectively communicating with said regulating chamber to supply the pressurized gas thereto, a second orifice selectively communicating with said regulating chamber for delivering the pressurized gas in said regulating chamber to said main inhalation conduit, an axial tubular baffle which reduces and shifts the noise spectrum resulting from the flow of gas towards the high frequencies, a third orifice selectively communicating with said regulating chamber for venting ambient air, a moving member, a main check valve coupled to said moving member, and a secondary check valve coupled to said moving member, said moving member causing said main check valve to move from a first position which closes said third orifice to a second position which fully opens said third orifice and enables ambient air to be vented therethrough, wherein said secondary check valve is moved to a position which partially closes said second orifice when said main check valve is moved to said second position, in order to determine said residual flow rate under said pressure close to zero (0); an exhalation valve interposed in said secondary exhalation conduit; and an operating circuit coupled to said flow regulating valve and said exhalation valve, said circuit operating said flow regulating valve based on the flowrate and pressure of said gas in said main inhalation conduit as measured downstream past said flow regulating valve in order to determine the beginning the inhalation phase of each of the breathing cycles of the patient, and said circuit causing said exhalation valve to open during the exhalation phase of each of the breathing cycles of the patient.

Claim 18

An apparatus for assisting with the ventilation of a patient breathing in successive cycles, each of the cycles including an inhalation phase and an exhalation phase, said apparatus being of the type including an inhalation assistance mode, triggered by the patient during the beginning of the inhalation phase, which causes said apparatus to deliver to the patient a flowrate of gas under a pressure equal to a given reference value, said apparatus comprising: a source of pressurized gas, said source including an outlet orifice which delivers a flowrate of pressurized gas, an inlet where a partial vacuum prevails; a face mask for placing over the upper airways of a patient, whereby said face mask enables the patient to receive said flowrate of pressurized gas delivered from said outlet orifice of said source; and a transmission circuit for coupling said source to said said face mask, said transmission circuit including: a main inhalation conduit coupled between said outlet orifice of said source of pressurized gas and said face mask; a discharge orifice; a secondary exhalation conduit for communicating with said face mask, said secondary exhalation conduit being coupled between said main inhalation conduit and said discharge orifice; a flow regulating valve interposed in said main inhalation conduit, said flow regulating valve including means for maintaining a residual flowrate of gas under a pressure of approximately zero in said main inhalation conduit during the exhalation phase of each of the breathing cycles of the patient; a distributor controlled by said operating circuit, said distributor including two inlets and one outlet, one of said two inlets coupled to said outlet of said source and the other of said two inlets coupled to said inlet of said source, said outlet of said distributor coupled to said exhalation valve, said distributor having an open and closed position to one or the other of said two inlets; a pneumatically-operated exhalation valve interposed in said secondary exhalation conduit, said exhalation valve being supplied by said distributor; and an operating circuit coupled to said flow regulating valve and said exhalation valve, said circuit operating said flow regulating valve based on the flowrate and pressure of said gas in said main inhalation conduit as measured downstream past said flow regulating valve in order to determine the beginning the inhalation phase of each of the breathing cycles of the patient, and said circuit causing said exhalation valve to open during the exhalation phase of each of the breathing cycles of the patient.

Claim 19

An apparatus for assisting with the ventilation of a patient breathing in successive cycles, each of the cycles including an inhalation phase and an exhalation phase, said apparatus being of the type including an inhalation assistance mode, triggered by the patient during the beginning of the inhalation phase, which causes said apparatus to deliver to the patient a flowrate of gas under a pressure equal to a given reference value, said apparatus comprising: a source of pressurized gas, said source including an outlet orifice which delivers a flowrate of pressurized gas, an inlet where a partial vacuum prevails; a face mask for placing over the upper airways of a patient, whereby said face mask enables the patient to receive said flowrate of pressurized gas delivered from said outlet orifice of said source; and a transmission circuit for coupling said source to said said face mask, said transmission circuit including: a main inhalation conduit coupled between said outlet orifice of said source of pressurized gas and said face mask; a discharge orifice; a secondary exhalation conduit for communicating with said face mask, said secondary exhalation conduit being coupled between said main inhalation conduit and said discharge orifice; a flow regulating valve interposed in said main inhalation conduit, said flow regulating valve including means for maintaining a residual flowrate of gas under a pressure of approximately zero in said main inhalation conduit during the exhalation phase of each of the breathing cycles of the patient; a distributor controlled by said operating circuit, said distributor including two inlets and one outlet, one of said two inlets coupled to said outlet of said source and the other of said two inlets coupled to said inlet of said source, said outlet of said distributor coupled to said exhalation valve, said distributor having an open and closed position to one or the other of said two inlets; a pneumatically-operated exhalation valve interposed in said secondary exhalation conduit, said exhalation valve being supplied by said distributor; and an operating circuit coupled to said flow regulating valve and said exhalation valve, said circuit operating said flow regulating valve based on the flowrate and pressure of said gas in said main inhalation conduit as measured downstream past said flow regulating valve in order to determine the beginning the inhalation phase of each of the breathing cycles of the patient, and said circuit causing said exhalation valve to open during the exhalation phase of each of the breathing cycles of the patient.