Portable gas powered positive pressure breathing apparatus and method
AssigneeEmergent Respiratory Products, Inc.
InventorsRobert M. Hamilton, Anthony J. Gambone
Life of this patent
Estimating the term…
Abstract
A portable positive pressure breathing apparatus includes a demand valve with a supply inlet port adapted to be connected to a pressurized source of oxygen and an outlet port adapted to be connected to the inlet of a patient's breathing appliance. The demand valve further includes a reference chamber and a valve assembly responsive to the reference chamber/appliance inlet pressure differential for connecting/disconnecting the inlet port to and from the outlet port. At least one manually adjustable back pressure regulator is connected to the pressure source and the reference chamber for setting the pressure in the reference chamber (and inlet to the breathing appliance) at a selected level above atmospheric pressure.
Claims34
In a continuous positive airway pressure apparatus for supplying breathable gas from a pressurized source to an individual's breathing appliance, which appliance has an inlet for receiving the gas and an inhalation/exhalation valve for routing the gas to the individual's lungs and the exhaled air to the atmosphere, the apparatus comprising:
- a demand valve having a supply inlet port adapted to be connected to the pressurized source, an outlet port adapted to be connected to the appliance's inlet, a reference chamber and a valve assembly responsive to the reference chamber pressure and a pressure representative of the appliance inlet pressure for connecting and disconnecting the inlet port to and from the outlet port;
- and
- at least one back pressure regulator connected to the pressurized source and the reference chamber for setting the pressure in the reference chamber at a selected level above atmospheric pressure.
A method of treating a patient suffering from pulmonary edema or other respiratory ailment comprising:
- a) securing a breathing appliance to the patient's airway, the appliance having an inlet and an inhalation/exhalation valve to allow breathable gas passing through the inlet to enter the patient's lungs during the inhalation phase and allow expired air to exit to atmosphere during the exhalation phase;
- b) providing a pressurized source of breathable gas;
- c)providing at least one reference pressure at a selected value above atmospheric pressure;
- d) monitoring the pressure at the appliance inlet;
- e) comparing the appliance inlet pressure with the reference pressure;
- f) connecting and disconnecting the pressurized source to the mask inlet when the inlet pressure falls below and rises to the reference pressure, respectively;
- and
- g) varying the selected value of the reference pressure during the treatment.
In a CPAP apparatus for supplying breathable O2 from a pressurized source to an individual's breathing appliance, which appliance has a patient valve with an inlet for receiving the O2 and an inhalation/exhalation valve for routing the O2 to the individual's lungs and the exhaled air to the atmosphere, the apparatus comprising:
- a demand valve having a supply inlet port adapted to be connected to the pressurized source, an outlet port adapted to be connected to the appliance's inlet, a reference chamber and a valve assembly responsive to the reference chamber/appliance inlet pressure differential for connecting and disconnecting the demand valve inlet port to and from the demand valve outlet port;
- and
- at least one back pressure regulator connected to the pressurized source and the reference chamber for setting the pressure in the reference chamber at a selected level above atmospheric pressure.
A patient inhalation/exhalation valve for directing breathable gas from a pressure regulated source to a patient's lungs and exhausting the patient's expired air to the atmosphere comprising:
- a housing having an upper section and an interior wall, the housing further having an inlet adapted to be connected to the regulated source, an exhaust port in fluid with the atmosphere and an inlet/outlet chamber adapted to be placed in fluid communication with the patient's lungs;
- an inhalation valve disposed between the inlet and the inlet/outlet chamber;
- a flexible diaphragm secured at its periphery to the inner wall of the housing and suspending a rigid valve member, the diaphragm and valve member forming a first chamber with the interior of the upper housing section;
- the inlet/outlet chamber terminating at its upper end in a circular valve seat arranged to engage a lower circular sealing area of the rigid valve member, the valve member and the seat forming an exhalation valve so that when the valve member is positioned above the seat the exhalation valve is opened connecting the inlet/outlet chamber to the exhaust port and when the valve member engages the seat the exhalation valve is closed;
- the first chamber being in fluid communication with the housing inlet;
- the effective area of the diaphragm and valve member supported thereby being about equal to the area of the circular valve seat whereby the exhalation pressure is maintained at a level approximately equal to the pressure in the inlet.
Dependencies are inferred from the claim text.