A kind of external device and analysis method for gases of initiatively simulating human body autonomous respiration
Technical field
The invention belongs to and breathe medical science physiology research field, be specifically related to a kind of novel external active simulated lung model and design, realization and the application of gas analyzing apparatus.
Background technology
In clinical position, using artificial simulated lung does not possess simulation human body autonomous breathing at present, cannot meet the Research Requirements of auxiliary type ventilating mode, and lack flowing through measurement and the analytic function of simulated lung gas flow and gas ingredients, a kind of objective data analysing method that can be quantitative is provided cannot to clinical practice and medical scientific.
Summary of the invention
The object of the invention is to set up a kind of novel external active simulated lung model, provide a kind of and can accurately to the gas flow of the simulated lung of flowing through, composition, carry out the method for Measurement and analysis.
The object of the invention is to be achieved through the following technical solutions: a kind of external device of initiatively simulating human body autonomous respiration, it is characterized in that: comprise by the circulation gas circuit that drives lung ventilator, two-chamber simulated lung, head dead space model-composing, drive lung ventilator to be connected with the input end of two-chamber simulated lung, two-chamber simulated lung output terminal is connected with head dead space model through gas analyzing apparatus, and described gas analyzing apparatus comprises oxygen concentration sensor, pressure transducer, flow sensor, signal conditioning circuit, data acquisition unit and communication interface; Described flow sensor is provided with an air intake opening, a gas outlet, flow sensor air intake opening end is connected with head dead space model, flow sensor gas outlet end is connected with two-chamber simulated lung, described pressure transducer is connected with the air intake opening of flow sensor by connector hose, the output terminal of oxygen concentration sensor is connected with data acquisition unit through signal conditioning circuit, flow sensor, pressure transducer output terminal are connected with data acquisition unit, and data acquisition unit is connected with computing machine by communication interface.
Apply an analysis method for gases for said apparatus, its step is as follows:
1) data of data acquisition unit Real-time Collection flow sensor, oxygen concentration sensor obtain gas flow rate, oxygen concentration;
2) result that in device monitoring being obtained, real-time oxygen concentration and air-breathing/exhalation flow rate multiply each other is carried out integration, obtain oxygen flow and the tidal volume of exhalation/inhalation in each respiratory cycle, again both are carried out to division arithmetic, obtain average effective fraction of inspired oxygen in inspiratory phase/expiratory phase; Concrete formula is as follows:
The oxygen flow of inspiratory phase:
The tidal volume of inspiratory phase:
The oxygen flow of expiratory phase:
The tidal volume of expiratory phase:
Effective oxygen intake concentration:
=
: the oxygen flow of inspiratory phase
: the tidal volume of inspiratory phase
: the oxygen flow of expiratory phase
: the tidal volume of expiratory phase
: effective oxygen intake concentration.
Beneficial effect of the present invention: the present invention has built a kind of novel external device of initiatively simulating human body autonomous respiration, this apparatus structure is compact, is easy to routine maintenance and changes element, and easy accessibility is simple.Can be used for the scientific research of various ventilating modes: by driving ventilator parameter is set, the breathing state of simulation different crowd; Also can be used for the comparison and detection of lung ventilator performance: lung ventilator to be tested is connected with head dead space model, gas analyzing apparatus can be accurately to flowing through the pressure of gas, flow velocity and oxygen content gas are measured and are analyzed, and draw corresponding trend map and oscillogram.Oxygen concentration sensor adopts novel oxygen concentration cell, concentration-response speed is exceedingly fast, fast-changing oxygen concentration in energy Real-Time Monitoring high-speed gas, and utilize the result that self-editing software multiplies each other to oxygen concentration and air-breathing/exhalation flow rate to carry out integration, can obtain oxygen flow and the tidal volume of exhalation/inhalation in each respiratory cycle, again both are carried out to division arithmetic, obtain the average oxygen concentration that sucks gas in inspiratory phase/expiratory phase.Such computing method make testing result more accurate, and testing result approaches true.
Accompanying drawing explanation
Fig. 1. structural representation of the present invention.
Fig. 2. gas analyzing apparatus structural representation in the present invention.
Fig. 3. oxygen concentration sensor signal conditioning circuit figure.
Fig. 4 is analysis method for gases software flow pattern.
Fig. 5 is tidal volume and effective fraction of inspired oxygen output waveform figure.
Specific embodiments
As shown in Figure 1: apparatus of the present invention air path part comprises driving lung ventilator 9, two-chamber simulated lung 8 and head dead space model 7, to drive lung ventilator 9 to be connected with a chamber (as actuator chamber) of two-chamber simulated lung 8, another one chamber (as test chamber) be connected with head dead space model 7.Drive lung ventilator 9 according to setup parameter work, drive the rule of the actuator chamber volume of two-chamber simulated lung 8 to change, between actuator chamber and test chamber, by a metal link rod, be connected, make test chamber synchronize and conduct with the air-flow between actuator chamber, simulate the autonomous respiration of human body.
Wherein driving lung ventilator is that NEWPORT company produces, model: the HT50 of button nation.Two-chamber simulated lung 8 is commercial product (U.S. FLUKE 1600).The 7 apery body head cavity size designs of head dead space model, the vent line that built-in pipe volume equates with person's windpipe volume.
Be connected to gas analyzing apparatus I structure between two-chamber simulated lung 8, head dead space model 7 as shown in Figure 2, comprise oxygen concentration sensor 1, pressure transducer 2, flow sensor 3, signal conditioning circuit 4, data acquisition unit 5 and communication interface 6; The MPXV5004G type product that the Free scale company that wherein pressure transducer 2 adopts produces, what flow sensor 3 adopted is the AWM700 series of products of Honeywell company, gather real-time inspiratory flow rate (sample frequency is 30 milliseconds), oxygen concentration sensor 1 adopts oxygen cell (response time (t
10% ~ 90%) be 300 milliseconds) be the OOM109 type product that ENVITEC company produces, be used for gathering real-time oxygen concentration, what data acquisition unit 5 adopted is the USB2832 product of Beijing Art Technology Development Co., Ltd..Flow sensor 3 is provided with an air intake opening, a gas outlet, flow sensor 3 air intake opening ends are connected with head dead space model 7, flow sensor 3 gas outlet ends are connected with two-chamber simulated lung 8, pressure transducer 2 is connected with the air intake opening of flow sensor 3 by connector hose, and flow and pressure transducer just can prepare to detect pressure and the flow that flows through gas.Oxygen concentration sensor 1 is used for detecting the oxygen concentration of the two-chamber simulated lung 8 of flowing through.The output area of flow, pressure transducer all, in the allowed band of data acquisition unit 5, need not be carried out signal condition.The signal of oxygen concentration sensor 1 output is fainter, not in the acquisition range of data acquisition unit 5, so will carry out being input in data acquisition unit 5 after necessary amplification conditioning to signal again.Signal conditioning circuit is as shown in Figure 3: the output signal of oxygen concentration sensor 1 is connected to the forward input signal end of OP07, and by regulating R1, the resistance of Rf, amplifies 100 times by signal, and the signal of output is removed and disturbed through RC filtering, obtains stable voltage signal.
Data acquisition unit 5 transfers data to computing machine 10 by usb communication interface, via data analysis software, carries out record, analyzes, and software flow is as follows:
1) initialization data;
2) judge that whether data are effective;
3) if data are effective, data are stored;
4) according to the data calculated flow rate and the oxygen concentration that gather;
5) display waveform.
Data analysis process:
1) data of data acquisition unit Real-time Collection flow sensor, oxygen concentration sensor obtain gas flow rate, oxygen concentration;
2) result that in device monitoring being obtained, real-time oxygen concentration and air-breathing/exhalation flow rate multiply each other is carried out integration, obtain oxygen flow and the tidal volume of exhalation/inhalation in each respiratory cycle, again both are carried out to division arithmetic, obtain average effective fraction of inspired oxygen in inspiratory phase/expiratory phase;
Concrete formula is as follows:
The oxygen flow of inspiratory phase:
The tidal volume of inspiratory phase:
The oxygen flow of expiratory phase:
The tidal volume of expiratory phase:
Effective oxygen intake concentration:
=
: the oxygen flow of inspiratory phase
: the tidal volume of inspiratory phase
: the oxygen flow of expiratory phase
: the tidal volume of expiratory phase
: effective oxygen intake concentration.