WO2006067822A1

WO2006067822A1 - Apparatus for assisted ventilation

Info

Publication number: WO2006067822A1
Application number: PCT/IT2005/000742
Authority: WO
Inventors: Tito Mario Franco Passannanti; Francesco Diurno
Original assignee: Tito Mario Franco Passannanti; Francesco Diurno
Priority date: 2004-12-20
Filing date: 2005-12-19
Publication date: 2006-06-29
Also published as: EP1830913A1; ITNA20040072A1

Abstract

A respiratory circuit connected with an inspiratory-expiratory line (I, E) of a life support machine (R), which separates at the beginning the gas emission for both lungs. On the circuit of one (LU1) of the two (LU1, LU2) lungs there is an inspiratory-expiratory valve (VI, VE) device with electromechanic command and electronic control (C, M) able to modulate the respiratory flows and pressures in the whole range of ventilator’s pressures. Separated lung ventilation can be obtained, as well, with a ventilator provided of a double flow generator in which the respiratory lines of the two lungs are completely separated.

Description

TITLE APPARATUS FOR ASSISTED VENTILATION

* * * *

DESCRIPTION The present invention relates to an apparatus for the assisted ventilation . The apparatus can be used, in particular, associated to an automatic ventilator for allowing a ventilation separated for the two lungs . As better explained in the description, with this invention it' s possible to realize a separated lung ventilation with a single ventilator isolating completely the respiratory flows of the two lungs and changing, if required, flow and insufflation' s pressure of one of them.

This kind of ventilation is indicated in several respiratory diseases . The main are : lobar bronchopneumonia, pulmonary fibrosis, thoracic trauma (pulmonary contusion) , atelectasis , thoracic surgery anaesthesia, etc .

Nowadays it' s possible to ventilate separately the lungs using o otracheal bilumen tubes connected with two ventilators coupled in series by an interfacing system of the two ventilators in which one is the leader and gives the command for frequency and both are singularly regulated on pressure and volume data of each lung. This system is extremely complicated, expensive and has limited relevance specially in many ICUs in which there is one ventilator for each bed. In thoracic surgery anaesthesia there is one single ventilator connected in the end of the respiratory circuit by a Y link at the orotracheal bilumen tube . In the monopulmonary phase of ventilation one of the two respiratory lines is closed to exclude the ventilation of the lung .

However, . it' s <not possible to keep the excluded lung in a static overdistension, because it could reduce the right-left shunt and consequently reduce a possible right ventricular overload .

The main aim of the present invention is to eliminate the above drawbacks . These results have been achieved according to the invention thanks to the idea of producing an apparatus having the features described in independent claim. Other features relate to the dependant claims . Among the advantages of the present invention there are : it is possible to ventilate separately both lungs (or a single pulmonary lobe) with a single ventilator which is connected to the respiratory tract with a system with separated flows , being able to realize the mechanical ventilation separately for the two lungs with a single ventilator; it is possible to obtain a respiratory circuit with a device provided with valves which, with independent ' operations, it is able to realize ventilation conditions with separated lung ventilation and separated lobes ventilation; it is possible to obtain a rotatory circuit separated in its inspiratory and expiratory elements of the two lungs , with separation of the two tracts, for each lung, at the output of the ventilator; it' s impossible the mixture of expired gasses of the two lungs in the circuit, said mixture being possible only in the end portion of the expiratory tract of line; it is impossible also the mixture of inspired gasses to the two lungs because the separation is realized on the inspiratory line of the ventilator; it is possible to graduate the two inspiratory and expiratory fluxes of a single lung thanks to the presence of a device with valves disposed on the inspiratory and expiratory lines of one of the lungs , said device being able to be provided with two valves, one on the inspiratory line, the other on the expiratory line, totally independent each other; it is possible to control the flow, the pressure and the volume of the mono-pulmonary and mono- lobular ' inspiratory and expiratory lines (or bi- lobular in the case of two lobes connected to a common broncus ) , with the possibility to send data to a control system with micro-processor, system which is able to command the opening or the closing of valves disposed on the respiratory circuit, said valves being able to have an electromechanical command and being graduated in their opening and closing, with the possibility of instantaneous correction of the opening of the same valves by the micro-processor; the values of flow and pressure can be programmed with the possibility to utilize said data by the micro-processor in a mono-pulmonary respiratory circuit ; it is possible, by a graphic system, the dynamic study of the mono-pulmonary and mono-lobular function (or bi-lobular in the case of two lobes connected to a common broncus ) , with the possibility to execute the study of the contra-lateral pulmonary function by the graphic system of the main ventilator, being always possible to control the therapeutic effectiveness on each single lung, by two separated graphic systems ; - it is possible to modify in every moment the entity of ventilation of the controlled lung, switching from a separated lung ventilation to a traditional bi-pulmonary ventilation, when therapeutic action occurs; - it is possible to provide a double-component system, with a disposable element, consisting in the respiratory circuit with an hermetic opening for the interfacing of sensors and valves , and the no disposable elements consisting in the electronic and electro-mechanic component ; in another embodiment, the disposable element can comprise the valves, with the no disposable elements which comprise the mechanical command of the same valves ; it is possible the insertion in a ventilator' s process, of a flux and pressure regulation system on a mono-pulmonary respiratory line to realize a separated lung ventilation; it is obtainable a mechanical ventilator provided with two separated pressure generators with independent graphic systems , programming and sensors able to realize a separated lung ventilation with a single ventilator; the apparatus of the invention can be use in combination with the ventilators of known type and has a relatively easiness of use; the apparatus of the invention maintains unaltered its features even after a prolonged use, with a reduced maintenance .

These and other advantages and characteristics of the invention will be best understood by anyone skilled in the art from a reading of the following description in conjunction with the attached drawings given as a practical exemplification of the invention, but not to be considered in a limitative sense, wherein :

- Fig .1 " is ^" a schematic representation of a possible embodiment of the present invention;

- Fig .2 is a detail view of the embodiment of Fig . l ;

- Figs . 3 , 4 , 5 and 6 show schematically possible embodiments of the invention;

- Fig . 7 is a schematic representation of another embodiment of the invention, in which it is possible separately ventilate and control also pulmonary lobes .

According to the invention, with reference to the examples, of . ,Figs . 1-6, an apparatus A for the assisted ventilation is of the type usable disposed between an automatic ventilator and the respiratory lines Ll, L2 destined to two lungs Lϋl, LU2.

The apparatus is provided with measurement and regulation means V, SF, SP of the flows of inspiration and expiration, independent for the two lungs LUl, LU2 and connected to a single respirator

R. In particular, as better explained later, the apparatus is provided with a first respiratory line Ll and with a second respiratory line L2 , said measurement and regulation means being provided at least on said first respiratory line Ll . The means of measurement and regulation comprise valvular means VI , VE, independent each other and disposed on the inspiration duct Il and expiration ducts El of said respiratory line Ll , and sensor means SF, SP of the flow and/or the pressure disposed on the ducts of inspiration Il and expiration El , said sensor means being disposed upstream and downstream of the valvular means VI , VE . The means of measurement and regulation can be connected to a control circuit with micro-processor C, M . Said control circuit C, M is programmable in order to - be ' -*able to operate said measurement and regulation means V, SF, SP . Moreover, the apparatus can be provided with visualization means G for allowing the dynamic study of the mono-pulmonary function and/or the contralateral pulmonary function .

According to the example represented in Figs . 1 and 2 , the separation of the flows inspiratory and expiratory for the two lungs LUl and LU2 takes place directly at the outlet of the respirator R and this in order to avoid, with two separated rotatory circuits , one for each lung, the mixture of the inspired gases with the expired gases . From the separation of the flows, a respiratory line (L2 ) , relative to a lung (LU2 ) , is completely free, being able to distribute gas with the preset data of pressure of the respirator R; the other respiratory line L2 , relative to contra-lateral lung LUl is subj ect to the action of the apparatus A, which is provided with valves, one (VI ) disposed on the inspiratory line ( II ) and the other (VE) on the expiratory line (El ) , for modulating the relevant flows . In Fig . 1 the valves are marked with V, while in Fig . 2 with VI and VE . The operation of the valves is electromechanical and the control of the opening 'and closing of the same is determined by a micro-processor which elaborates the data coming from the flow sensors (disposed upstream and downstream of the valves ) and regulates the opening or the closing of the valves according to values of pressure, time and flow predetermined by the operator . The opening and the closing of the valves are thus regulated by pressure, flow and time values programmed by the operator . The two respiratory circuits for the two lungs end with an antibacterial filter and a "Mount" link, to an orotracheal bilumen tube that takes the gasses separately to both lungs .

The system comprises a respiratory circuit which is separated in two parts at the outlet of the ventilator R. On the inspiratory and expiratory output (marked with I and E in Fig . l ) there is a "Y" link so to have a double circuit separated at the beginning, one for each lung. A circuit L2 is completely independent so it ventilates the lung with the modality programmed by the ventilator R. As it' s a ■ rotatory circuit, it' s impossible the mixture of inspired and expired gasses . The second circuit is rotatory too and is originated by the other line of the Y link; on its way to the orotracheal tube there is an apparatus A, provided with valve device with flow reducer . The apparatus of invention is provided with two valves VI , VE, one on the inspiratory line Il and the other one on the expiratory line El . The two valves have an electro-mechanic command that can modulate their closing : the valves can be completely closed without flow and can be absolutely opened, with a flow value equal to the one programmed on the ventilator that is the same for the other lung . The working of the valves is independent so that the interaction of the two can give all the possible pressure values from zero (no flow) to a static overdistension that corresponds to the peak pressure programmed on the ventilator . If the inspiratory valve VI is closed, the lung will be excluded from ventilation; if the expiratory valve VE is totally closed and the inspiratory one VI is open, there will be a static overdistension of the lung . Modulating the valves by graduating the closing, it' s possible to increase the end expiration pressure',^{' "} to ^' reduce the end inspiration pressure ( PEEP) , to ventilate lung with high PEEPs and low tidals , for all pressure values between expired and inspired extremes . It' s possible to change the time that defines the inspiration-expiration ratio, giving to the expiratory valve a late or a slow opening so to create a kind of inspiration break, as soon as the expiratory valve of the main ventilator opens to let expiratory phase begin . Both lungs will have j ust expiratory frequency in common that , related to respiratory frequency, in separated lung ventilation, is an essential condition to avoid hemodinamic disorders . The apparatus comprises a sensors system. The sensors 'are disposed upstream and downstream of the two valves VI an VE and comprise flow and pressure sensors , marked generically with S-F-P in Fig . l and with SF and SF in Fig .2. On the inspiration line Il the sensors before (upstream) the valves have to recognize flow and pressure to be modulated . The downstream sensors are located as a control system. On the contrary, on the expiration line El, distal sensors have to recognize gas pressure and the flow coming out from the lung . The proximal sensors (going toward the ventilator) have to modulate exactly the time of the expiratory phase , recognizing the instant when the main ventilator expiratory valve opens . The apparatus comprises a control system M, C . This system, provided with a microprocessor M, gathering sensors information, will modulate the opening and closing of the valves, sending signals to an electromechanical operating system. Unit C, strictly connected with the microprocessor, will verify the precision of the parameters set at the exit of the two valves . ' ■*

There is a programming system P, provided with visualization means G (display) . This system has to gather the ventilation data, required by the operating doctor, and send them to the control system so to occur in an active way, on valve system. The visualization or graphic means G allow the graphic visualization of flow and pressure waves .

The respiratory circuit can be composed by two separated components : a disposable element , comprising the real circuit , the Y link and the valve device . The electronic components are part of the fixed equipment . Before .setting ventilation parameters, we must previously make valuations about respiratory functionality, acting on lungs separately . "Compliance" curves (volume/pressure curves ) flow/time curves , volume/time curves, can be separately extrapolated for each lung . For the not controlled lung, the curves can be extrapolated directly on the main ventilator, by closing inspiratory and expiratory valves of the controlled respiratory line, so to exclude in it the respiratory flux . Controlled lung functionality curves "can^' be directly extrapolated from the graphic system connected to the suggested respiratory circuit .

There also can be extract data about auto PEEP values and intra-alveolar flux redistribution in disomogeneous lung ( static compliance) by end expiration pause and end inspiration pause function

(the same functions can be extracted from the main respiratory, for contra-lateral lung) . Test of mono pulmonary alveolar recruitment can be besides done, by setting , pptimal PEEP for each lung . It ' s possible, in point of fact, to study each lung separately and choose the best ventilation for each of them, either for PEEP, or peak pressure, or inspiration/expiration ratio .

In addiction to the one proposed, separated lung ventilation technique with a single ventilator can be also done by making different variants . Proposed circuit, with valve device, is a totally independent flux and mono pulmonary pressure regulation system, able to detect and modify ventilation flows in a ventilator . Separated lung ventilation technique with one ventilator can be also done by arranging the main ventilator for this aim.

For example, inserting in the ventilator the valve and control system, just after an internal division of monopulmonar respiratory lines . In this way the respiratory circuits of the two lungs will come out from the ventilator . This possible embodiment is shown in Fig .5 , where A and A' indicate the two apparatus for the two lungs . Another embodiment, shown in Fig .6, provides for making an interface system K between valve device A and the ventilator R, so to simplify on the external equipment, graphic and sensor systems, according to respiratpry power. In other words , the apparatus A is connected to the ventilator R by an interface device K, able to allow the adjustment of the ventilator R on the base of the signals received by the measurement and regulation means of the flows . In Fig . 4 is shown a ventilator provided with two flow sources H, H' , with completely independent graphic systems , sensors, program means , valves , and two external expiratory circuits Ll and L2, explicitly appropriate for each lung . In practice, the apparatus comprises second measurement and regulation means (A' ) , acting on the second respiratory line (L2 ) , and the apparatus (A) is disposed internal to an automatic ventilator (R) provided with , two flow sources (H, H' ) _r connected to said first (Ll) and second (L2 ) respiratory lines . The apparatus A, as in Fig.3 , can comprise second measurement and regulation means (indicated by A' ) acting on the second respiratory line L2. The apparatus A can comprise second measurement and regulation means ( indicated by A' ) acting on the second respiratory line L2 ; the apparatus is disposed internal to an automatic ventilator R provided with a flow source (H) with two inlet/outlet , connected to said first (Ll ) and second (L2 ) inspiratory lines (see Fig.5) . In Fig .7 is shown a further embodiment of the invention. In this example, a supplementary respiratory line (LS ) is associated to a main respiratory line (L) , connected to a ventilator (R) . The supplementary respiratory line (LS ) comprises a bronchoscopical sound-probe (B) , which can be selectively connected to a lobular bronchus . In this way it is possible to ventilate differentiately only the interested lobe (or two lobes if the two lobes are associated to a common bronchus, as anatomically defined for the inferior and medium right lobes) . In the shown embodiment, the distal end of the bronchoscope (B) is inserted in the medium lobe (L02 ) of the right lung (LUl ) .

This embodiment of the invention thus allows differentiate ventilations respectively for : inferior right lobe (LOl) , medium right lobe (L02 ) , superior right lobe (L03 ) , inferior and medium right lobes (LOl, L02 ) , inferior left lobe (L04 ) , sperior right lobe (L05 ) . In practice, the main respiratory line (L) is connected to a j oint of "Mount" type (MO) . To the mount j oint (MO) is connected said supplementary line (LS) , which comprises the broncho-scope (B) and on which is acting the apparatus (A) . Advantageously, with this solution it is possible to measure selectively the values relating to a single lobe (or to two associates lobes , as for the medium and inferior right lobes) . In other words, it is possible to control , also day by day, the values of pressure and flow of a single lobe and, at the same time, it is possible to decide the parameters according which the ventilation is executed.

Claims

1. Apparatus for the assisted ventilation, usable disposed between an automatic ventilator and the respiratory lines for the two lungs, characterized in that it is provided with measurement and regulation means (V, SF, SP) of the inspiration and expiration flows independent for the two lungs (LUl, LU2 ) and/or for one or more pulmonary lobes (LOl , L02 , L03', L04 ,^' L05 ) , said means being connected to a single ventilator (R) .

2. Apparatus according to claim 1 characterized in that it is provided with a first respiratory line (Ll ) and a second respiratory line (L2 ) , said measurement and regulation means being disposed at least on said first respiratory line (Ll ) .

3. Apparatus according to claim 2 characterized in that said measurement and regulation means comprise valve means (VI , VE) independent each other and disposed on the inspiration ( II ) and expiration ducts (El) of said respiratory line (Ll ) .

4. Apparatus according to claim 2 characterized in that measurement and regulation means comprise sensor means ( SF, SP) for the flow and/or the pressure, disposed on the inspiration (II) and expiration ducts (El ) of said respiratory line (Ll ) .

5. Apparatus according to claim 2 characterized in that said measurement and regulation means comprise valve means (VI , VE) , independent each other and disposed on the inspiration ( II ) and expiration ducts (.El) • of * said respiratory line (Ll ) , and sensor means (SF, SP) for the flow and/or the pressure, disposed on the inspiration ( II ) and expiration ducts (El ) , .upstream and downstream of said valve means (VI , VE) .

6. Apparatus according to claim 1 characterized in that said measurement and regulation means are connected to a control circuit with micro-processor (C, M) .

7. Apparatus according to claim 6 characterized in that said control circuit (C, M) is programmable for driving said measurement and regulation means (V, SF, SP) .

8. Apparatus according to claim 6 characterized in that it ^■ is provided with visualization means (G) able to allow the dynamic study of the mono- pulmonary function and/or of the contra-lateral pulmonary function .

9. Apparatus according to claim 1 characterized in that it comprises a disposable component, constituted by the respiratory circuit, i . e . by the respiratory lines (Ll , L2 ) , said respiratory circuit being hermetically connectable to said measurement and regulation means of the flows .

10. Apparatus according to claim 9 characterized in that it comprises valve means (VI, VE) partially of disposable type .

11. Apparatus according to claim 2 characterized in that it comprises second measurement and regulation means (A^f ) acting on said second respiratory line (L2 ) .

12. Apparatus according to claim 2 characterized in that it comprises second measurement and regulation means (A' ) , acting on said second respiratory line

(L2 ) , said apparatus (A) being internal to an automatic ventilator (R) provided with a flow source (H) with two inlet/outlet connected to said first (Ll ) and second L2 ) respiratory lines .

13. Apparatus according to claim 2 characterized in that it ^' comprises second measurement and regulation means (A' ) , acting on said second respiratory line

(L2) , said apparatus (A) being internal to an automatic ventilator (R) provided with two flow sources (H, H' ) connected to said first (Ll ) and second L2 ) respiratory lines .

14. Apparatus according to claim 2 characterized in that the apparatus (A) is connected to the ventilator (R) by means of a interface device, able to allow the regulation of the ventilator (R) according to signals received from said measurement and regulation means .

15. Apparatus according to one of the preceding claims, characterized in that it comprises a broncho-scopic sound (B) selectively associable to a pulmonary lobe .