Two-gas variable ratio, variable dose, metering system and method of use

Claim 1

A device for administering pulsed doses of oxygen and an anesthetic gas to a patient in synchronization with the patient's breathing cycle comprising: two sets of gas displacer means, the first set for oxygen and the second set for the anesthetic gas, each set of said displacer means comprising two piston and cylinder pairs, each of said piston-cylinder pairs comprising a piston arranged to reciprocate within a cylinder, each said cylinder having one closed end, each said closed end having a single port for connection to a gas conduit, the two pistons in each said set connected so as to move in unison; lever means connecting the pistons of the two gas displacer means sets and arranged to synchronize the movement of the pistons of one said set with the movement of the pistons of the other said set; means to cause the pistons of each said gas displacer set to move in response to and in synchronization with the breathing cycle of a patient, and means for adjusting the length of stroke of said pistons moving in their respective cylinders, said means arranged to cause each of said pistons of both said gas displacer means to travel to its respective cylinder end on each piston stroke to thereby completely displace the gas charge within each said cylinder.

Claim 2

A device for administering pulsed doses of oxygen and an anesthetic gas to a patient in synchronization with the patient's breathing cycle comprising: two sets of gas displacer means, the first set for oxygen and the second set for the anesthetic gas, each set of said displacer means comprising two piston and cylinder pairs, each of said piston-cylinder pairs comprising a piston arranged to reciprocate within a cylinder, each said cylinder having one closed end, each said closed end having a single port for connection to a gas conduit, the two pistons in each said set connected so as to move in unison; lever means connecting the pistons of the two gas displacer means sets and arranged to synchronize the movement of the pistons of one said set with the movement of the pistons of the other said set; means to cause the pistons of each said gas displacer set to move in response to and in synchronization with the breathing cycle of a patient, and means for adjusting the length of stroke of said pistons moving in their respective cylinders, said means arranged to cause each of said pistons of both said gas displacer means to travel to its respective cylinder end on each piston stroke to thereby completely displace the gas charge within each said cylinder.

Claim 10

A system for administering pulsed doses of gaseous oxygen and an anesthetic gas to a patient in synchronization with the respiratory cycle of the patient and during the inhalation phase of said cycle, comprising: a set of oxygen displacers and a set of anesthetic gas displacers, each set having two gas displacement means arranged to operate in unison; means to synchronize the operation of the set of oxygen displacers with the operation of the set of anesthetic gas displacers; valve means adapted to move back and forth between a first position and a second position in response to sensed inhalations of the patient; first conduit means arranged when said valve means is in its first position to connect a source of oxygen through said valve means to one of said oxygen gas displacement means and to connect the other of said oxygen gas displacement means through said valve means to a cannula adapted to communicate with the nasal passages of the patient and to reverse said connections when the valve means is in its second position; and second conduit means arranged when said valve means is in its first position to connect a source of anesthetic gas through said valve means to one of said anesthetic gas displacement means and to connect the other of said anesthetic gas displacement means through said valve means to said cannula and to reverse said connections when the valve means is in its second position.

Claim 11

A system for administering pulsed doses of gaseous oxygen and an anesthetic gas to a patient in synchronization with the respiratory cycle of the patient and during the inhalation phase of said cycle, comprising: a set of oxygen displacers and a set of anesthetic gas displacers, each set having two gas displacement means arranged to operate in unison; means to synchronize the operation of the set of oxygen displacers with the operation of the set of anesthetic gas displacers; valve means adapted to move back and forth between a first position and a second position in response to sensed inhalations of the patient; first conduit means arranged when said valve means is in its first position to connect a source of oxygen through said valve means to one of said oxygen gas displacement means and to connect the other of said oxygen gas displacement means through said valve means to a cannula adapted to communicate with the nasal passages of the patient and to reverse said connections when the valve means is in its second position; and second conduit means arranged when said valve means is in its first position to connect a source of anesthetic gas through said valve means to one of said anesthetic gas displacement means and to connect the other of said anesthetic gas displacement means through said valve means to said cannula and to reverse said connections when the valve means is in its second position.

Claim 23

A method for administering one pair of adjustably premetered doses of physiologically active respiratory gases in synchronism with the breathing cycle of a patient while simultaneously premetering a second, equal set of the same two gases in preparation for the next dose delivery comprising: volumetrically premetering and storing at constant pressure a first adjustable dose of a first physiologically active gas into a first gas displacer means while simultaneously volumetrically premetering and storing at constant pressure a second dose of a second physiologically active gas into a second gas displacer means in adjustably coordinated ratio to the said first dose; and in response to a signal triggered by the onset of an inhalation of said patient, delivering by forced displacement both of said doses to said patient at the same volumetric ratio of flow rates as the ratio of the premetered volumes while simultaneously volumetrically premetering another set of equally sized doses of both gases into said first and second displacer means, and repeating the cycle of simultaneous premetering and delivery actions in response to subsequent signals signifying the onset of subsequent inhalations.

Claim 24

A method for administering one pair of adjustably premetered doses of physiologically active respiratory gases in synchronism with the breathing cycle of a patient while simultaneously premetering a second, equal set of the same two gases in preparation for the next dose delivery comprising: volumetrically premetering and storing at constant pressure a first adjustable dose of a first physiologically active gas into a first gas displacer means while simultaneously volumetrically premetering and storing at constant pressure a second dose of a second physiologically active gas into a second gas displacer means in adjustably coordinated ratio to the said first dose; and in response to a signal triggered by the onset of an inhalation of said patient, delivering by forced displacement both of said doses to said patient at the same volumetric ratio of flow rates as the ratio of the premetered volumes while simultaneously volumetrically premetering another set of equally sized doses of both gases into said first and second displacer means, and repeating the cycle of simultaneous premetering and delivery actions in response to subsequent signals signifying the onset of subsequent inhalations.