DE102005039220B3 - Breathing apparatus, used for patient during operation, comprises hand breathing bag with actuating sensor connected to inspiratory line via connecting line - Google Patents

Abstract

Breathing apparatus comprises a hand breathing bag (34) with an actuating sensor (36) connected to an inspiratory line (10) via a connecting line (32). The inspiratory valve (18), overpressure valve (38) or control device can be adjusted to an elevated level using the actuating sensor. Preferred Features: The actuating sensor is a volume flow sensor which is in the connecting line between the inspiratory line and the hand breathing bag.

Description

The The invention relates to a ventilator according to the preamble of Claim 1.

In usually a patient has to an operation artificially be ventilated. Mostly, the reason is that a muscle relaxant Drug is administered to allow the surgeon to work. This medication paralyzes also the respiratory muscles. Usually is the breathing gas during the ventilation is gaseous Anesthetic z. As is added to isoflurane, sevoflurane or desflurane, which to maintain anesthesia. Also the use of nitrous oxide is still very common.

Of the Boiling point of listed Anesthetic is slightly higher as the room temperature. Therefore, these liquid funds must be converted into the gaseous phase by means of so-called evaporators, before they are added to the breathing gas. The patient only takes one Fraction of the anesthetic over the lungs up. The biggest part is exhaled again.

In order to minimize these losses of expensive drugs, a so-called circular system is used in anesthesia ventilation with gaseous anesthetics, ie, the patient's own exhaled air is fed back. The carbon dioxide content is previously filtered out with the help of a CO ₂ absorber, such as soda lime. A fresh gas supply into the circular system compensates for the oxygen consumed. This fresh gas is previously passed over the anesthetic vaporiser, so that there is a set at the evaporator anesthetic agent concentration in the circuit system.

In usually these systems work in excess, i. H. the fresh gas volume flow is higher as the patient consumption. about the height of the fresh gas volume flow, the user thus regulates the Rückatemanteil. The surplus flows from the circulatory system into the anesthetic gas suction of the hospital. The patient is ventilated with the gas from the circulatory system either by machine expressing an integrated bellows or by manual expressions a serving as a reservoir hand ventilation bag in the circle system.

For the anesthesiologist is the hand ventilation option on the anesthesia machine essential. It serves to control the intubation, whether the Tube is right, and it allows give him a control of the respiratory mechanics ("he has the lung in his hand") and she gives it the possibility anytime additional if necessary manual breaths to administer. Manual ventilation on the one hand and mechanical ventilation as well as spontaneous breathing of the patient on the other hand are not simultaneous possible. The anesthesiologist must do this each time the respective function z. B. by moving a lever activate.

By the development of highly potent anesthetics with drastically reduced levels Half-life intravenously via infusion syringe pumas be administered, an alternative to gaseous anesthetics. In this so-called total intravenous anesthesia (TIVA) with the anesthetics very short half-life leaves the effect of the drug very quickly after switching off the pump to. But also with these anesthetics muscle relaxants administered, the patient must be ventilated.

However, this is no complicated circle system required, but it is enough an open system like intensive care ventilators. However, are known Intensive care ventilators not readily suitable because they have no Handbeatmungsmöglichkeit feature. However, this function is, as already mentioned above, a "must" for the anesthesiologist.

Of the Invention is the object of a ventilator as open System to provide, in addition to manual ventilation option has and in the operating mode manual ventilation simultaneously the possibility for spontaneous breathing or mechanical ventilation.

These Task is in a ventilator according to the preamble of Claim 1 solved by the features of this claim.

further developments and advantageous embodiments will become apparent from the dependent claims.

By connecting the hand-held breath bag to the inspiratory line, the hand-held breath bag is filled with fresh breathing gas in the same concentration of air and O ₂ as is delivered to the patient during mechanical or spontaneous breathing. A rebreathing already with CO ₂ enriched gases is thus avoided.

However, the mere connection of the hand-held breathing bag to the inspiratory line is not sufficient to allow manual ventilation. Namely, the pressure and / or volumetric flow control would attempt to compensate for pressure or volume flow changes through the hand-held breathing bag and to maintain the set pressure or volumetric flow in the inspiratory line and the expiratory line. A handbeat would be so hindered.

Of the Handbeatmungsbeutel therefore includes an actuation sensor and by means of operating sensor is the expiratory valve or an additional adjustable pressure relief valve controlled in such a way that during the operation of the Handbeatmungsbeutels in the breathing circuit one opposite in the mechanical ventilation currently existing pressure level increased pressure level established. The control of the expiratory valve or the additional pressure relief valve via the Pressure and / or flow control or a separate controller. The anesthesiologist has the opportunity again A control of the respiratory mechanics and can be extra at any time if needed manual breaths to administer. There is no manual switching of valves necessary. simultaneously The patient may be at the CPAP level set on the ventilator breathe spontaneously.

Preferably is the actuation sensor a volumetric flow sensor located in the connecting pipe between the Inspiration line and the hand-held breathing bag.

There the volume flow through the connecting line is a criterion for actuating the hand-held breathing bag represents, the signal of the volume flow sensor for control the exhalation valve or the additional adjustable pressure relief valve be used.

Further can be in the connecting line between the inspiratory line and the hand-held breathing bag, a valve to be disposed during the activity hand breath bag and while its filling open and while the mechanical ventilation is closed.

One Soft hand-held breathing bag, constantly with the inspiratory line would be connected in dependence of pressure in the inspiratory line stretch and relax and an additional Form compliance parallel to the patient's lungs. volume delivery to the patient and volume measurements of the inhaled and exhaled Gases would thereby falsified. Through the valve in the connecting line between the inspiratory line and The hand-held breathing bag becomes the hand-held breathing bag during the mechanical ventilation and spontaneous breathing without desired manual ventilation separated from the inspiratory and then forms no compliance parallel to the lungs.

The Valve in the connecting line between the inspiratory line and the manual ventilation bag can be either manually or by a separate Control be controlled.

Thereby let yourself achieve automatic control of the valve.

following The invention will be explained with reference to an embodiment, the is shown in the drawing.

The illustrated ventilator includes an inspiratory conduit connectable to an air and oxygen network 10 and an expiratory line openable to the atmospheric environment 12 , At the entrance of the inspiratory line 10 are feed valves 14 . 16 with a mixing device 42 for a controlled supply of air and oxygen and at the exit of the expiratory line 12 a controllable expiratory valve 18 arranged. The feed valves 14 . 16 and the expiratory valve 18 are via a pressure and / or flow control 20 controlled. Additionally is in the inspirational line 10 a pressure relief valve 22 arranged.

The connection to the air and oxygen network is via gas plug 24 . 26 which are connected to specially coded gas outlets of a central gas supply to a hospital. By means of the pressure and / or flow control 20 is via the feed valves 14 . 16 set the mixing ratio of air and oxygen according to the user's specifications. The oxygen content in the breathing gas can thus be adjusted between 21% for air only and 100% for oxygen only.

The inspirational line 10 and the expiratory line 12 are to a Y-piece 28 together. From the Y-piece 28 either introduces a tube into the trachea of a patient 30 or a face mask is connected, through which a patient can be ventilated either through the nose or mouth. The ventilator described so far enables both mechanical ventilation and spontaneous breathing. For additional manual ventilation, the ventilator includes one on the inspiratory line 10 over a connecting line 32 connected hand-held breathing bag 34 with an actuation sensor 36 and an additional controllable and adjustable pressure relief valve 38 in the expiratory line 12 , This additional pressure relief valve 38 is via the pressure and / or volume flow control 20 or a separate control during operation of the hand-held breathing bag 36 adjustable to a higher than the mechanical ventilation pressure level.

Due to the additional adjustable pressure relief valve 38 and additional control 20 the manual ventilation option can be retrofitted to an existing ventilator without that a mechanical intervention in the housing of the ventilator is necessary. In a new design, it is also possible the anyway necessary exhalation valve 18 and the pressure and / or flow control 20 to use by extension of the control software.

Further, in the connection line 32 between the inspiratory line 10 and the hand-held breathing bag 36 a valve 40 arranged during the operation of the hand-held breathing bag 36 and during its filling is opened and closed during mechanical ventilation without desired manual ventilation. During spontaneous breathing, it may be open or closed. This valve 40 is operated manually, but can also current control in new design by pressure and / or volume 20 or a separate controller can be controlled.

During mechanical ventilation, inspiration is provided by the controlled feed valves 14 . 16 and the mixing device 42 creates an overpressure in the lungs and respiratory tract of a patient. The pressure is adjusted depending on the elasticity of the system lung and chest and the volume flow dependent resistances in the airways and is about 15 to 25 hPa. The amount of the resulting flow rate is about 20 to 50 L / min and the Respiratory tract resistances have values of 5 hPa / (L / s) in healthy humans and up to more than 100 hPa / (L / s) in chronic obstructive illnesses eg. B. asthmatic. The reciprocal of elasticity, the compliance, is between 60 and 100 mL / hPa in a healthy person. In case of severe pneumonia, compliance may fall to levels below 20 mL / hPa.

The expiration is achieved by opening the expiratory valve 18 initiated. Thus, the existing in the lungs and in the airways pressure can be reduced by the expiratory flow. As a rule, the overpressure is not completely reduced, but only up to the so-called PEEP value, the Positive End Exspiratory Pressure value. As a result, the lungs at the end of the exhalation is kept somewhat bloated.

To provide inspiration for mechanical ventilation, the two feed valves open 14 . 16 in proportion to the oxygen concentration set by the user on the device. By design of the feed valves 14 . 16 as proportional valves, these react quickly and precisely to control commands. Through the feed valves 14 . 16 the gas pressure of the air and oxygen network is reduced from originally 3 and 6 bar to the specified Atemdrücke.

At this stage is the expiratory valve 18 closed and the mixed gas flows into the lungs of the patient 30 , The feed valves 14 . 16 remain open until the desired volume or pressure has been delivered. In so-called pressure-controlled ventilation, the set pressure is maintained for a defined time. This requires the feed valves 14 . 16 If necessary, supply respiratory gas to compensate for leaks or gas escaping to other areas of the lungs.

After closing the feed valves 14 . 16 and opening the expiratory valve 18 escapes the pressurized air from the lungs via the expiratory line 12 , Since, as already mentioned, the pressure is usually not completely eliminated, but a PEEP persists, the expiratory valve 18 often referred to as PEEP valve. Maintaining this PEEP, even with patient leaks and inspiratory effort, is a dynamic system. Each pressure drop is compensated by supplying breathing gas and regulating the PEEP valve.

at The spontaneous breathing without ventilator expands in the inspiratory phase of the Chest by lowering the diaphragmatic muscle and possibly by lifting of the rib cage with the help of the intercostal muscles. Through this Volume increase arises a negative pressure opposite the atmospheric pressure in height from about 2 to 5 hPa in the alveoli and respiratory tract. From this results in an inspiratory flow in the trachea and further over the bronchi into the alveoli.

These Inspiration is an active process because of the expansion of the chest only possible with muscle power is. In contrast, expiration is a passive process. As soon as the muscles relax again, the chest cavity opens Reason of elastic forces together again and thus creates an overpressure on the inhaled Air. This flows therefore about the bronchi, the trachea and the pharynx-pharynx back into the atmosphere.

A spontaneous breathing with ventilator is made possible by the fact that the ventilator provides a so-called by-or bias volume flow. This is a constant flow rate of 3 to 10 L / min, which flows through the tube system from inspiratory outlet via the inspiratory tube 10 , the Y-piece 28 and the expiratory tube 12 to the expiratory valve 18 flows. Due to the open system, the patient can breathe spontaneously at any time. In this case, the respectively required breathing gas through the constant flow and possibly an additional flow due to the provided responsive control. In spontaneous breathing, this function is referred to as CPAP, namely continuous positive airway pressure, since the pressure in these airways is always above atmospheric pressure.

Next pure controlled ventilation, in which the machine covers the whole Breath work takes over, and the exclusive one Spontaneous breathing also uses mixed forms to treat the essential To sustain and adequately support spontaneous breathing. This applies z. For example ineffective spontaneous breathing, such as too small volumes when needed from the ventilator by increasing the pressure supported at the beginning of inspiration becomes. Therefor assigns the pressure and / or flow control trigger systems to Recognition of the inspiratory efforts of the Patients on.

In manual ventilation, the anesthesiologist may administer additional manual breaths to the patient as needed. This is the purpose of the inspiratory line 10 over a connecting line 32 connected hand-held breathing bag 34 which is operated by the anesthesiologist.

Actuation is by the volume flow sensor 36 trained actuation sensor detected and as a control signal to a controller 20 forwarded. The control 20 then causes the exhalation valve 18 or the additional adjustable pressure relief valve 38 to set a higher pressure level compared to mechanical ventilation. Normally, namely the pressure and / or flow control 20 by opening the expiration valve 18 try to reduce an increase in pressure and thus restore the pressure necessary for mechanical respiration or spontaneous breathing. By influencing the expiratory valve 18 In contrast, a compensation is avoided and thus the breath is specifically supplied to the lungs of the patient. It does not escape unused via the exhalation valve 18 ,

With a hard hand-held breathing bag, this measure would already be sufficient. Under hard is understood here that the hand-held ventilation bag 34 in the unfolded state does not depend on the pressure while under soft is understood that the hand-held ventilation bag 34 stretched in the deployed state depending on the pressure and thus would form a compliance to the patient's lungs.

Also with a soft hand-held breathing bag 34 to be able to work, that is in the connection line 32 between the inspiratory line 10 and the hand-held breathing bag 34 arranged valve 40 needed. This is only during the operation of the hand-held breathing bag 34 and during its filling opened and closed during mechanical ventilation. This is the hand-held breathing bag 34 with mechanical ventilation or spontaneous breathing without additional manual ventilation separated from the inspiratory line and then forms no compliance with the patient's lungs 30 , With the valve open 40 in manual ventilation mode, the patient may 30 Spontaneously spontaneously breathe spontaneously at the CPAP level set on the ventilator.

Claims (5)

Ventilator with an inspiratory line connectable to an air and oxygen network ( 10 ) and an expiratory line openable to the atmospheric environment ( 12 ), whereby at the entrance of the inspiratory line ( 10 ) controllable feed valves ( 14 . 16 ) for a controlled supply of air and oxygen and at the exit of the expiratory line ( 12 ) a controllable expiratory valve ( 18 ) and the feed valves ( 14 . 16 ) and the exhalation valve ( 18 ) via a pressure and / or volume flow control ( 20 ), characterized in that at the inspiratory line ( 10 ) via a connecting line ( 32 ) a hand-held breathing bag ( 34 ) with an actuation sensor ( 36 ) and by means of the actuation sensor ( 36 ) the expiratory valve ( 18 ) or an additional adjustable pressure relief valve ( 38 ) via the pressure and / or volume flow control ( 20 ) or a separate control during actuation of the hand-held breathing bag ( 34 ) is adjustable to a relative to mechanical ventilation increased pressure level. The ventilator according to claim 1, characterized in that the actuation sensor ( 36 ) is a volume flow sensor in the connecting line ( 32 ) between the inspiratory line ( 10 ) and the hand-held ventilation bag ( 34 ) is arranged. Breathing apparatus according to claim 1 or 2, characterized in that in the connecting line ( 32 ) between the inspiratory line ( 10 ) and the hand-held ventilation bag ( 34 ) further a valve ( 40 ), which during the operation of the hand-held breathing bag ( 34 ) and during its filling and is closed during mechanical ventilation. Breathing apparatus according to claim 3, characterized in that the valve ( 40 ) is controlled manually or by the separate controller. Ventilator according to claim 3, characterized in that valve ( 40 ) is closed or open during spontaneous breathing so that spontaneous breathing is possible at any time.