JPS6223495Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a ventilator that supplies breathing gas in a vibrating state to a patient experiencing difficulty in breathing, thereby causing artificial respiration.

As is generally well known, breathing is functionally a gas exchange that takes in oxygen and expels carbon dioxide within a living body (patient). The lungs, where this breathing takes place, consist of a trachea that branches into many branches, and capillaries that surround the alveoli formed at the end of the trachea.
Gas exchange occurs between the alveoli and blood vessels. The gas exchanged in this way is discharged to the outside air by gas diffusion in the peripheral airways, which have approximately 18 branches or more, considering the number of tracheal branches.
In airways with large branches, ventilation is achieved through expansion and contraction of the chest.

Conventionally, patients whose breathing is impaired due to various causes have been treated with so-called artificial respiration, which assists the ventilation described above. Such artificial respiration methods include not only intermittent positive pressure breathing (IPPV) but also end-expiratory non-positive airway pressure (PEEP; breathing in which positive pressure is retained or externally applied during the expiratory phase until the end of the expiratory phase). (method) was also widely practiced, and patients with severe respiratory failure began to be saved. but,
Applying the above breathing methods, especially positive end-expiratory pressure breathing, has disadvantages such as pressure injuries such as pneumothorax due to increased airway pressure, and decreased cardiac output due to increased intrathoracic pressure. Artificial ventilation may not be effective in patients with the most severe obstructive ventilatory failure or bronchial fistula. In such cases, conventionally, long-term extracorporeal circulation (ECMO) using a membrane oxygenator was the only available option. However, this long-term extracorporeal circulation method requires a lot of manpower and equipment, and long-term management is impossible. Therefore, an artificial respiration method was devised that artificially promotes diffusion, which is the other physiological means of gas exchange. The principle of this artificial respiration method is that it is difficult to obtain sufficient ventilation efficiency to maintain a living body by relying solely on molecular movement for diffusion, so high-frequency vibrations are applied externally to cause molecular movement. The idea is to stimulate the The actual frequency applied externally is about 200 times/minute to 5,000 times/minute, and by applying such high vibrations, even in apnea without ventilation, the partial pressure of oxygen and carbon dioxide in the blood can be reduced. It is possible to maintain the carbon partial pressure at a normal level. This type of artificial respiration method is called High Frequency Osillation (HFO). A structure shown in FIG. 1 is known as a high-frequency ventilator, which is a device for carrying out this high-frequency ventilatory method. In the figure, reference numeral 1 is a patient circuit. This patient circuit 1 includes an endotracheal tube 2 inserted into a patient's trachea and a main body 3 integrally connected to the endotracheal tube 2.
It is composed of. An inlet 4 for introducing breathing gas into the patient circuit 1 is provided in the middle of the main body 3 . Further, reference numeral 5 denotes a reciprocating pump, and this reciprocating pump 5 has a cylinder 7 having a connecting port 6 connected to the main body 3 of the patient circuit 1.
and a piston 8 that slides back and forth within this cylinder 7.
, a connecting rod 9 that is rotatably connected to the piston 8 , and a crank 10 that is rotatably connected to the connecting rod 9 and slides the piston 8 via the connecting rod 9 . There is. The supply and exhaust volume of the reciprocating pump 5 is variable within a range of about 0 to 100 c.c. so that it can be set to any volume depending on conditions such as the patient's vital capacity and medical condition.
The adjustment method is performed by changing the length of the crank 10. And the reciprocating pump 5
No matter what volume the supply/exhaust volume of the piston 8 is set, the midpoint of the reciprocating path of the piston 8 (the
1/2 point) is set to always be located at the same point on the cylinder 7. For example, as shown in Fig. 2, let L be the length of the reciprocating path of the piston 8 on the cylinder 7 when the supply and exhaust volume is the maximum 100 c.c., and a point halfway along the path (L/2) Let be a. If the length of the reciprocating path of the piston 8 on the cylinder 7 in the case of 20c.c. is l, then the point half (l/2) of this path is also set to be a. It is. This is so that the reciprocating pump will not be affected even if the supply/exhaust volume is increased or decreased as necessary. In addition, this reciprocating pump 5
is set to supply and exhaust air at high vibration frequencies from 100 times/minute to 5,000 times/minute.

Therefore, breathing gas can be supplied into the patient's trachea through the patient circuit 1 while applying high vibrations by the reciprocating pump 5, and as a result, even in an apnea state without ventilation, the partial pressure of oxygen and carbon dioxide in the blood can be increased. The partial pressure can be maintained at a normal level, allowing artificial respiration to be performed without putting strain on the patient's lungs and heart.

However, the conventional high-frequency respirator mentioned above has
The smaller the intake and exhaust volume is set, the more so-called dead space is created in the cylinder 7 where the piston 8 does not slide, and as a result, the vibrations generated by the reciprocating motion of the cylinder 7 are weakened before reaching the trachea. It has the disadvantage of being sticky. This state will be explained using cases where the supply/exhaust volume is 100c.c. and 20c.c. As shown in Figure 2, the supply and exhaust volume is 100
In the case of cc, the piston 8 slides back and forth within the cylinder 7 from end to end, so no dead space is created within the cylinder 7. However, if the supply/exhaust volume is set to 20 c.c., the piston 8 will slide back and forth over the above 1/2 of the intermediate point a, and the cylinder 7
A dead space corresponding to the length of L/2-1/2 is created inside. Due to this dead space, the amplitude of the vibration of the breathing gas caused by the sliding movement of the cylinder 7 is greatly weakened, and as a result, gas exchange within the trachea cannot function normally. Put it away.

This idea was made in view of the above circumstances,
The purpose is to provide a reciprocating pump-type high-frequency ventilator that can freely change the supply and exhaust volume, and which does not create dead space in the cylinder no matter what volume of supply or exhaust is set. A plurality of reciprocating pumps are provided, and these reciprocating pumps are connected in parallel to the patient circuit.

This idea will be explained below with reference to the drawings. Third
The figure shows an embodiment of the high-frequency respirator according to this invention. In the figure, the same reference numerals as in FIG. 1 indicate the same constituent elements, and the explanation thereof will be omitted. In the figure, reference numeral 11... is a cylinder whose internal volume (supply/exhaust volume) is set to 20 c.c. A piston 12 is slidably provided in each of these five cylinders 11, and each piston 12 is connected to a connecting rod 13.
It is removably connected to the support rod 14 via. The connecting rod 9 is rotatably connected to the support rod 14. Further, each cylinder 11 is connected in parallel to the patient circuit 1 via a manifold 15. Note that the clamp 10 is used with a constant length, and is set so that no dead space is always created in the cylinder 11.

Next, a method of using the high-frequency respirator having the above structure will be explained. First, when used at 100 c.c., all five connecting rods 13 are kept connected to the supporting rod 14, and the supporting rod 9 is operated via the crank 10 and the connecting rod 9. Next, when you want to increase the supply and exhaust volume to 80 c.c., select any one of the five connecting rods 13 and disconnect the connecting rod 13 and support rod 14. If the support rod 14 is operated in this state, any one of the pistons 13 will not operate, and an air supply/displacement amount of 80 c.c. can be obtained without creating a dead space in the cylinder. Next, 60 c.c.,
If you want to change the supply and exhaust volume from 40c.c. to 20c.c., add any connecting rods 13 (one for 60c.c., two for 40c.c., two for 20c.c. If ., select 3) and connect the connecting rod 13.
The connection between the support rod 14 and the support rod 14 may be released. In this way, the supply and exhaust volume is changed by stopping the sliding of any one of the plurality of pistons 12, instead of changing the sliding length of one piston as in the conventional method. Therefore, the air supply and exhaust volume can be changed without creating a dead space as in the conventional case. Therefore, depending on the patient's condition in the above-mentioned high-frequency ventilator,
Even if an arbitrary supply/exhaust volume is set, vibrations can always have a sufficient amplitude, and effective artificial respiration can be performed on the patient.

FIG. 4 shows another embodiment of the high-frequency ventilator according to the invention, in which the same reference numerals as in FIG. 3 indicate the same components, and the explanation thereof will be omitted. In the figure, reference numeral 16... is a three-way valve, and this three-way valve 16...
As shown in the figure, cylinder 11... and manifold 15
...is established between. This three-way valve 16...
... is provided with an exhaust port 16a... at one end thereof, and by switching the T-shaped flow path of this three-way valve 16... as shown in Fig. 5, the cylinder 11... is vented to the outside air. Can be opened.
If such a three-way valve 16... is provided, the piston 12... can be moved without disconnecting the support rod 14... and the connecting rod 13... each time it is necessary to change the supply/exhaust amount. You can select any air supply/exhaust amount at any time while the system is in operation. Therefore, by adopting the above structure, it is possible to continuously increase or decrease the air supply and exhaust volume while the high-frequency ventilator is operating according to the patient's symptoms, and furthermore, the high-frequency ventilator can be used to reduce its usefulness. It can be assumed that there is.

In addition, in the above embodiment, the number of cylinders is 5.
The supply and exhaust volume of each cylinder was set to 20c.c., but the number of cylinders is not limited to these values, and the number of cylinders can be set to any number, and the supply and exhaust volume can be set to any number of cc. Good too.

Further, in the above embodiment, one connecting rod and crank are provided for a plurality of pistons, but each piston may be provided with one connecting rod and crank. By allowing each piston to slide independently in this manner, the sliding period of each piston can be slightly shifted, and smooth vibration can be obtained.

As explained above, the high-frequency ventilator according to this invention is provided with a plurality of reciprocating pumps that vibrate breathing gas supplied into the trachea through the patient circuit, and these reciprocating pumps are connected to the patient circuit. Since the reciprocating pump is connected in parallel with the reciprocating pump, the supply and exhaust volume can be changed without creating dead space within the reciprocating pump, and vibrations with sufficient amplitude can be applied to the breathing gas in the trachea.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a conventional high-frequency ventilator, Fig. 2 is an explanatory diagram for explaining the action of a reciprocating pump in a conventional high-frequency ventilator, and Fig. 3 is a high-frequency ventilator according to this invention. Fig. 4 is a block diagram showing another embodiment of the same high-frequency ventilator; Fig. 5 is a block diagram showing an example of the respirator; Fig. 5 shows the operation of the three-way valve of the high-frequency ventilator shown in Fig. 4. FIG. 1... Endotracheal tube, 4... Inflow port, 9...
Connecting rod, 10... crank, 11... cylinder,
12... Piston, 13... Connecting rod, 14... Support rod.

Claims (1)

[Scope of utility model registration request] A high-frequency ventilator comprising a patient circuit having a breathing gas inlet and a reciprocating pump connected to the patient circuit and vibrating the breathing gas, wherein the reciprocating pump is composed of a plurality of reciprocating pumps, A high-frequency ventilator characterized in that these reciprocating pumps are connected in parallel to the patient circuit.