Blood gas parameter measuring system
First Claim
1. A system for invasive measurement of blood gas parameters, including pH, pO2 or pCO2, or for measuring other parameters influencing the time constant of an excited state of a fluorescent dye, comprising:
- (a) a light generation device including(a1) a generator having an outer signal (2),(a2) a controllable delay device (4) having at least two delay states and(a3) a light source means (6) coupled to said generator (2) via said delay device (4) for producing excitation light of a first wavelength;
(b) a fluorescent measuring probe (1) provided with(b1) a fluorescent dye that is positionable in ion exchange connection with blood;
(b2) said fluorescent dye adapted to be brought to an excited state by means of light of a first wavelength and returning, while emitting light of a second wavelength, from the excited state to a ground state with a time constant depending on the blood gas parameter to be measured,(c) a light reception device (16) for converting light of said first and second wavelengths into a received signal;
(d) a switchable light guide means (7)(d1) having at least two states and optically coupled between said light source (6);
said light reception means (16) and said fluorescent measuring probe (1), for coupling, in a first switched state, light of the first wavelength from the light source (6) to the fluorescent measuring probe (1) and light of the second wavelength from the fluorescent measuring probe (1) to the light reception means (16), and(d2) for guiding light of the first wavelength from the light source means (6) to the light reception means (16) in a second switched state;
(e) a phase metering means (17 to 20, 23 to
27), coupled to said generator (2) and said light reception means (16)(e1) for producing a phase reference signal phaselocked to the output signal of the generator (2) and responsive to the received signal from the light reception means (16),(e2) to produce a phase metering signal indicative of the phase difference between said output and receive signals;
(f) an evaluation means (28) connected to said phase metering means,(f1) and responsive to phase metering signals in the at least two delay states of said controllable delay device (4), when said switchable light guide means (7) is(f2) in the second switched state, for determining the transfer characteristic of the blood gas parameter measuring system, and(f3) which, in the first switched state of the light guide device (7), determines a value of the blood gas parameter on the basis of the transfer characteristic, the phase metering signal and a correlation between the respective values of the blood gas parameter and dependent values of said time constant, said correlation being predetermined for the fluorescent measuring probe (1).
1 Assignment
0 Petitions
Accused Products
Abstract
A system for invasive measuring of blood gas parameters, such as pH, pO2 or pCO2 , or for measuring other parameters influencing the time constant of the excited state of a fluorescent dye, comprises a light generation device including a generator (2), a delay device (4) and a light source (6), a fluorescent measuring probe (1), a light reception device (16), a light guide device, which is adapted to be switched over and which, in its first switching state, optically connects the light source (6) to the fluorescent measuring probe (1) and said probe (1) to the light reception device (16) and which, in its second switching state, establishes an optical connection between the light source (6) and the light reception device (16), a phase metering device (17to 20, 23 to 27) as well as an evaluation device (28), which, in the second switching state of the light guide device (7), determines the transfer characteristic of the blood gas parameter measuring system and which, in the first switching state of the light guide device (7), determines the measuring value of the blood gas parameter on the basis of the transfer characteristic, the output signal of the phase metering device (17 to 20, 23 to27) and a correlation between the respective values of the blood gas parameter and the associated values of the time constant of the fluorescent measuring probe (1), said correlation being predetermined for the fluorescent measuring probe (1).
-
Citations
14 Claims
-
1. A system for invasive measurement of blood gas parameters, including pH, pO2 or pCO2, or for measuring other parameters influencing the time constant of an excited state of a fluorescent dye, comprising:
-
(a) a light generation device including (a1) a generator having an outer signal (2), (a2) a controllable delay device (4) having at least two delay states and (a3) a light source means (6) coupled to said generator (2) via said delay device (4) for producing excitation light of a first wavelength; (b) a fluorescent measuring probe (1) provided with (b1) a fluorescent dye that is positionable in ion exchange connection with blood; (b2) said fluorescent dye adapted to be brought to an excited state by means of light of a first wavelength and returning, while emitting light of a second wavelength, from the excited state to a ground state with a time constant depending on the blood gas parameter to be measured, (c) a light reception device (16) for converting light of said first and second wavelengths into a received signal; (d) a switchable light guide means (7) (d1) having at least two states and optically coupled between said light source (6);
said light reception means (16) and said fluorescent measuring probe (1), for coupling, in a first switched state, light of the first wavelength from the light source (6) to the fluorescent measuring probe (1) and light of the second wavelength from the fluorescent measuring probe (1) to the light reception means (16), and(d2) for guiding light of the first wavelength from the light source means (6) to the light reception means (16) in a second switched state; (e) a phase metering means (17 to 20, 23 to
27), coupled to said generator (2) and said light reception means (16)(e1) for producing a phase reference signal phaselocked to the output signal of the generator (2) and responsive to the received signal from the light reception means (16), (e2) to produce a phase metering signal indicative of the phase difference between said output and receive signals; (f) an evaluation means (28) connected to said phase metering means, (f1) and responsive to phase metering signals in the at least two delay states of said controllable delay device (4), when said switchable light guide means (7) is (f2) in the second switched state, for determining the transfer characteristic of the blood gas parameter measuring system, and (f3) which, in the first switched state of the light guide device (7), determines a value of the blood gas parameter on the basis of the transfer characteristic, the phase metering signal and a correlation between the respective values of the blood gas parameter and dependent values of said time constant, said correlation being predetermined for the fluorescent measuring probe (1). - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A system for invasive measuring of blood gas parameters, such as pH, pO2, pCO2, and other parameters influencing the time constant of the excited state of a fluorescent dye, comprising
(a) a first light source means (44) for producing excitation light of a first wavelength; -
(b) a second light source means (45) for producing excitation light of a second wavelength, (c) a fluorescent measuring probe (40) provided with (c1) a fluorescent dye positionable in ion exchange connection with blood, (c2) said fluorescent dye being adapted to be brought to an excited state by means of light of a first wavelength and returning, while emitting light of a second wavelength, from the excited state to a ground state with a time constant depending on the blood gas parameter to be measured; (d) a first light reception means (46) for converting light of said second wavelength into a first reception signal; (e) a second light reception means (47) for converting light of said first and second wavelengths into a second reception signal; (f) a light guide means (48); (f1) for coupling light of the first wavelength from the first light source means (44) to the fluorescent measuring probe (40) and to the second light reception means (47), and for coupling light of the second wavelength from the fluorescent measuring probe (40) to the first light reception device (46) and (f2) for further coupling light of the second wavelength from said second light source means (45) to said first and second light reception means (46,
47);(g) a controllable delay device (61) connected to one of the light reception means (46,
47);(h) a phase metering means (62,
63), which is connected downstream of the delay means (61) and the other light reception device (46), for producing a phase metering signal indicative of the phase difference between the reception signals supplied therefrom,(i) an evaluation means (64); (i1) coupled to said phase metering means; (i2) which, when the second light source means (45) is activated is responsive to respective phase metering signals that result during at least two control states of the delay device (61), for determining the transfer characteristic of the blood gas parameter measuring system, and (i3) when the first light source means (44) is activated, determining a value of the blood gas parameter on the basis of the transfer characteristic, the phase metering signal and a correlation between the respective values of the blood gas parameter and the dependent values of the time constant, said correlation being predetermined for the fluorescent measuring probe (40). - View Dependent Claims (10, 11, 12, 13, 14)
-
Specification