Apparatus for the determination of the respiratory passageway resistance
AssigneeSiemens Aktiengesellschaft
InventorsManfred Franetzki, Volker Korn, Karl Prestele
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Abstract
An apparatus for the determination of the respiratory passageway resistance. Apparatus of that type in general evidence a flow resistance located in the respiratory passageway, whose resistance value is periodically varied at a frequency which is located above the breathing frequency, or a breathing tube with a flow resistance and a pulse generator for subjecting the breath flow with higher-frequencied pressure- or, respectively flow pulsations.
Claims10
In an apparatus for the quantitative determination of the respiratory passageway resistance including a breathing tube, a flow resistance cooperating with the tube so as to be in the path of the breath flow, pulse generator means for subjecting the breath flow within the tube with higher-frequencied flow pulsations and pressure measuring means for measuring the pressure in said breathing tube, the improvement comprising:
- a. said flow resistance being an elongate tube of predetermined length and internal diameter, which represents the approximately purely inductive part of a definite complex flow resistance with a known value (Re.sup.i.alpha.);
- b. said elongate tube being connected with an open end of the breathing tube;
- c. said pulse generator means being an alternating-flow pressure pump connected with the breathing tube;
- d. said pressure measuring means being set for the frequency of said alternating-flow pressure pump;
- e. and measuring means for indicating the respiratory passageway resistance as a function of said known pulsation flow (I), said known flow resistance (R) and the measured pressure fluctuations (P).
An apparatus as claimed in claim 30, said measuring means being calibrated pursuant to the equation ##EQU6## and said measured value being indicated therein as the respiratory passageway resistance.
In an apparatus for the quantitative determination of the respiratory passageway resistance, including a breathing tube, a flow resistance cooperating with the tube so as to be in the path of the breath flow, means for periodically varying the flow resistance with a frequency lying above the breathing frequency;
- and pressure measuring means for measuring the pressure in said breathing tube, the improvement comprising;
- a. said flow resistance being an elongate tube of predetermined length and internal diameter, which represents the approximately purely inductive part of a definite complex flow resistance with a known value (Re.sup.i.alpha.);
- b. said elongate tube being connected with an open end of the breathing tube;
- c. said elongate tube having a telescoping structure for effecting the periodic variation of said flow resistance;
- d. said pressure measuring means being set for the frequency at which said flow resistance is periodically varied;
- e. and measuring means for indicating the respiratory passageway resistance as a function of said known variable flow resistance (R), the known variation value of said flow resistance and the measured pressure fluctuations (P).
Dependencies are inferred from the claim text.