JP2016093227A - Air leak monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air leak monitoring device capable of providing information useful for grasping a patient's air leak state to a medical worker.SOLUTION: An air leak monitoring device includes a pressure sensor 15 for measuring pressure in a suction circuit connected to a patient's thoracic cavity, a display device 17 capable of displaying predetermined information, and a control unit 16 for performing calculation using the pressure measured by the pressure sensor 15. The control unit 16 includes a negative pressure calculation part 20 for calculating a minimum value of a negative pressure or a value close to it as a minimum negative pressure value NPmin based on the pressure for each predetermined time measured by the pressure sensor 15, and an output control part 26 for causing the display device 17 to output at least one of minimum negative pressure information Imin in which the minimum negative pressure value NPmin calculated by the negative pressure calculation part 20 is associated with the time, and minimum negative pressure-related information RImin related to the minimum negative pressure information Imin.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an air leak monitoring apparatus that monitors air leaks in which air leaks into a patient's chest cavity.

  Air leaks into the patient's chest cavity after chest surgery or during pneumothorax treatment. The leakage of air into the patient's chest cavity is commonly referred to as air leak. In order to discharge body fluids such as air leaking into the thoracic cavity and blood accumulated in the thoracic cavity, a suction circuit is connected to the thoracic cavity of the patient after thoracic surgery and the patient undergoing pneumothorax treatment. A treatment for aspirating body fluid such as blood accumulated in the thoracic cavity is performed on the provided drain bag or the like.

  As a method for detecting an air leak, a method in which a medical worker such as a doctor or a nurse visually observes air bubbles generated in a water seal chamber of a drain bag when an air leak occurs is known. In order to avoid the observation of bubbles by visual observation, there is known a device that detects air leaks by estimating the generation of bubbles based on pressure fluctuations in the suction circuit accompanying the generation of bubbles in the water-sealed chamber (patent) Reference 1). In addition, there are Patent Documents 2 to 4 as prior art documents related to the present invention.

JP 2014-136104 A JP-A-61-98263 JP 2000-60963 A International Publication No. 2011/118888

  In general, the suction circuit connected to the thoracic cavity is controlled so as to maintain the set negative pressure value, but not only when an air leak occurs but also when an event such as patient breathing or cough occurs, the pressure in the suction circuit Variations occur. For this reason, it is not always easy for a medical worker to accurately determine the presence or absence of an air leak by distinguishing an air leak from other events only by referring to the pressure fluctuation in the suction circuit. In addition, since the tendency and the degree of occurrence of air leak change in the process until the patient heals, the information on the tendency and degree of the occurrence of air leak is useful for grasping the current state of the patient. However, the information provided by conventional apparatuses and methods to medical staff may not always be useful for grasping the state of the presence or absence, the tendency of occurrence, and the degree of occurrence of air leaks.

  Then, an object of this invention is to provide the air leak monitoring apparatus which can provide the medical worker with the information useful for grasping | ascertaining the state of a patient's air leak.

  The first air leak monitoring device of the present invention is an air leak monitoring device (7) applied to a suction circuit (2, 32) connected in a chest cavity of a patient, and measures the pressure in the suction circuit. A measuring means (15); an output means (17) capable of outputting predetermined information; and a calculating means (16) for performing a calculation using the pressure measured by the pressure measuring means. A negative pressure calculating means (20) for calculating a minimum negative pressure value or a value in the vicinity thereof as a minimum negative pressure value (NPmin) on the basis of the pressure measured by the pressure measuring means every predetermined time; and the negative pressure calculating means The output means outputs at least one of the minimum negative pressure information (Imin) in which the minimum negative pressure value calculated by the time is associated with the minimum negative pressure information (RImin) related to the minimum negative pressure information. Output control means (26 When those having a (claim 1).

  Generally, the negative pressure in the suction circuit decreases due to the occurrence of air leak, and increases due to suction of a suction source provided in the suction circuit. Although the inside of the suction circuit is controlled to be held at a preset negative pressure value, the negative pressure in the suction circuit increases when the patient inhales. When the patient inhales, air due to air leak does not leak into the suction circuit in principle, and therefore the negative pressure in the suction circuit exceeds the set negative pressure value. Thus, for a patient being treated, the maximum negative pressure within a period can be said to have been caused by the patient's inspiration and aspiration source aspiration during that period. It can be said that the minimum value of the negative pressure within a certain period is caused by the occurrence of air leak within the period. Therefore, the maximum negative pressure value within a certain period is usually higher than the negative pressure value set mainly due to patient breathing, while the minimum negative pressure value during a certain period is set mainly due to the occurrence of air leaks. Lower than negative pressure value. Thus, the minimum negative pressure within a certain period is closely related to the air leak condition.

  According to the first air leak monitoring apparatus of the present invention, the minimum negative pressure information in which the minimum negative pressure value is associated with the time or the minimum negative pressure related information related to this information is output to the output means. Thereby, since such information closely related to the state of the air leak can be provided to the medical staff, it can be used for grasping the state of the air leak by the medical staff. For example, it is possible to determine the presence or absence of an air leak, that is, whether or not an air leak has occurred by grasping the magnitude of the minimum negative pressure value at a certain point in time from the minimum negative pressure information output to the output means. Further, since the minimum negative pressure information is information in which the minimum negative pressure value is associated with time, the medical worker can grasp the temporal change of the minimum negative pressure value by acquiring the output minimum negative pressure information. As the air leak occurs, the minimum negative pressure value is lower than the set negative pressure value, that is, the difference from the set negative pressure value increases. Therefore, if the medical staff knows the set negative pressure value in advance, the temporal change in the difference between the set negative pressure value and the minimum negative pressure value can be grasped. Thereby, the health care worker can determine whether the air leak is likely to occur, that is, whether the air leak is increasing or decreasing.

  When the minimum negative pressure value is calculated, the predetermined time may be appropriately determined. For example, 60 seconds may be set as the predetermined time, and the minimum negative pressure value or a value in the vicinity thereof may be calculated as the minimum negative pressure value. The value in the vicinity of the minimum value is a value within a range that does not hinder the handling of the negative pressure as the minimum value, and the range may be appropriately determined in consideration of a predetermined time or the like. When calculating the minimum negative pressure value, the minimum negative pressure value may be calculated by using the measured value measured by the pressure measuring means as it is, but the minimum value based on the average value of several measured values, for example, the moving average value, is the minimum. A negative pressure value may be calculated. The output means may be in any form as long as the medical staff can acquire the output information. For example, a display device that outputs information to the screen, a printing device that outputs information to a medium such as paper, or a speaker that outputs information as audio information may be used as the output means.

  In one aspect of the first air leak monitoring apparatus of the present invention, the output control means outputs a set negative pressure value (NPset) preset as a pressure in the suction circuit to the output means together with the minimum negative pressure information. (Claim 2). According to this aspect, since the set negative pressure value is output together with the minimum negative pressure information, it becomes easy for a medical worker to grasp the difference between the set negative pressure value and the minimum negative pressure value.

  The information to be output to the output means may be both the minimum negative pressure information and the minimum negative pressure related information, or either the minimum negative pressure information or the minimum negative pressure related information. Various information related to the minimum negative pressure information is assumed as the minimum negative pressure related information. For example, the minimum negative pressure related information is information in which a difference (ΔNPmin) between the minimum negative pressure value and a preset negative pressure value (NPset) preset as a pressure in the suction circuit is associated with time. (Claim 3). According to this aspect, since the minimum negative pressure related information is output, the medical worker can directly acquire the difference between the minimum negative pressure value and the set negative pressure value and the temporal change of the difference. The burden required for the worker to grasp the air leak state is reduced. Further, the minimum negative pressure related information may be information in which a fluctuation range (δNPmin) per predetermined time of the minimum negative pressure value calculated by the negative pressure calculating unit is associated with time (claim). 4). The larger the fluctuation range of the minimum negative pressure value, the stronger the occurrence of air leak. According to this aspect, since the medical worker can acquire the temporal change of the fluctuation range of the minimum negative pressure value by outputting the minimum negative pressure related information, for example, a period in which the fluctuation range is small continues for a long time. It can be estimated that no air leak has occurred within that period. That is, it can be used for the judgment of the presence or absence of an air leak by a medical staff.

  In one aspect of the first air leak monitoring apparatus of the present invention, the negative pressure calculating means determines a maximum negative pressure value or a value near the maximum negative pressure based on the pressure measured by the pressure measuring means for each predetermined time. A value (NPmax), and the output control means relates to the maximum negative pressure information (Imax) in which the maximum negative pressure value calculated by the negative pressure calculation means and time are associated with each other or the maximum negative pressure information. The maximum negative pressure related information (RImax) may be output to the output unit together with at least one of the minimum negative pressure information and the minimum negative pressure related information.

  As described above, in the case of a patient being treated, it can be said that the maximum value of the negative pressure within a certain period is mainly caused by the patient's inspiration within that period. A patient's breathing changes the state of the inspiratory flow rate and intensity associated with breathing depending on the patient's situation, for example, resting, talking, and coughing. Therefore, the maximum negative pressure value closely related to inspiration increases in the order of rest, conversation, and cough. According to this aspect, the maximum negative pressure information in which the maximum negative pressure value is associated with the time or the maximum negative pressure related information related to the information is output together with the minimum negative pressure information and the like. Therefore, when a medical worker acquires the maximum negative pressure information and the minimum negative pressure information at the same time, the determination of the presence or absence of air leak based on the minimum negative pressure information and the like can be associated with the patient's situation. For example, if a medical worker determines that an air leak has occurred based on minimum negative pressure information, etc., the maximum leak pressure information, etc. is also acquired, so that the air leak occurred at rest or occurred during conversation It can be used to determine whether it has occurred or occurred during coughing. For example, if a medical worker knows that the patient is close to healing when he knows that an air leak does not occur at rest or during conversation but only occurs during coughing, this aspect is more suitable for formulating a treatment policy. Can provide meaningful information to healthcare professionals.

  The value near the maximum value is interpreted in the same manner as the value near the minimum value described above. That is, it is a value within a range where there is no problem even if it is handled as the maximum value of the negative pressure, and the range may be appropriately determined in consideration of a predetermined time. In addition, the measurement value regarding the calculation method of the maximum negative pressure value may be handled in accordance with the above-described calculation of the minimum negative pressure value.

  The maximum negative pressure related information in this aspect is related to the maximum negative pressure information and may be any information as long as it is useful for determining the patient's situation. For example, the maximum negative pressure related information may be information in which a difference (ΔNPpp) between the maximum negative pressure value and the minimum negative pressure value is associated with time (Claim 6), or the maximum The negative pressure related information may be information in which a difference (ΔNPmax) between the maximum negative pressure value and a set negative pressure value (NPset) preset as a pressure in the suction circuit is associated with time. (Claim 7). Since the size of these pieces of information also changes depending on the patient's situation, it is useful for determining the patient's situation.

  There is no particular limitation on the configuration of the suction circuit to which the first air leak monitoring device of the present invention is applied. However, if a suction circuit is incorporated in the chest drain system that sucks the gas in the chest cavity of the patient through the water seal chamber, it is known that bubbles are generated in the water seal chamber as air leaks occur. Yes. By detecting the generation of the bubbles, it is possible to make a reliable air leak determination. Therefore, by outputting information on the bubble generation state together with the above-described maximum negative pressure information or maximum negative pressure related information, it is possible to reinforce the minimum negative pressure information for grasping the air leak state. Thereby, since the judgment of the state of the air leak by the medical staff becomes more accurate, the accuracy of the judgment according to the patient's situation is improved.

  For example, as one aspect of the first air leak monitoring apparatus of the present invention, the suction circuit uses the negative pressure generated by the suction source (5) to store the gas in the chest cavity with the liquid (L). Incorporated into the chest drain system (1B, 1C) for suction through the water sealed chamber (11, 41), the pressure measuring means measures the pressure between the suction source and the water sealed chamber. A bubble generation state acquisition unit (30) for acquiring a bubble generation state in the water seal chamber, wherein the output control unit is information related to the bubble generation state acquired by the bubble generation state acquisition unit. May be output to the output means together with at least one of the minimum negative pressure information and the minimum negative pressure related information in a state associated with time (claim 8). According to this aspect, as described above, the information related to the bubble generation state is output together with the minimum negative pressure information and the like in a state associated with the time. Improves. Examples of the bubble generation state include the flow rate and number of bubbles, the bubble generation duration, and the like. The bubble generation status can be obtained directly by using an optical sensor attached to the water seal chamber, and the pressure change associated with the bubble generation can be grasped from the measurement results of the pressure measurement means. It is also possible to do this.

  The second air leak monitoring device of the present invention is an air leak monitoring device (7) applied to a suction circuit (2, 32) connected in a chest cavity of a patient, and is a pressure for measuring the pressure in the suction circuit. A measuring means (15); an output means (17) capable of outputting predetermined information; and a calculating means (16) for performing a calculation using the pressure measured by the pressure measuring means. A negative pressure calculating means (20) for calculating a minimum negative pressure value or a value in the vicinity thereof as a minimum negative pressure value (NPmin) on the basis of the pressure measured by the pressure measuring means every predetermined time; and the negative pressure calculating means An air leak determination means for determining the presence or the occurrence tendency of air leaks in the chest cavity based on the minimum negative pressure value calculated by or a minimum negative pressure related value (ΔNPmin, δNPmin) related to the minimum negative pressure value ( 27) And output control means (26) for causing the output means to output information (Irs, Io) relating to the determination result of the air leak determination means (claim 9).

  As described above, for a patient being treated, the minimum negative pressure within a period is closely related to the air leak condition. According to the second air leak monitoring apparatus, the presence / absence or occurrence tendency of air leak is determined based on the minimum negative pressure value or the like, and information regarding the determination result is output. A medical worker in contact with the information on the determination result of the air leak can grasp the presence or the occurrence tendency of the air leak based on the information. Therefore, since the medical staff can know the occurrence or tendency of the air leak without judging the presence or the occurrence tendency of the air leak by itself, it is possible to reduce the burden required for formulating a treatment policy for the patient.

  In one aspect of the second air leak monitoring apparatus of the present invention, the calculation means includes the minimum negative pressure value as the minimum negative pressure related value, and a set negative pressure value preset as a pressure in the suction circuit ( And a data processing means (25) for calculating a difference (ΔNPmin) from the NPset), wherein the air leak determination means determines that the state in which the difference calculated by the data processing means is equal to or less than a threshold (Th1) is a determination time ( JT1) The presence or absence of the air leak may be determined on the basis of whether or not to continue.

  The greater the difference between the minimum negative pressure value and the set negative pressure value, the stronger the occurrence of air leak. Therefore, on the contrary, it can be said that the air leak does not occur as the difference is smaller. However, even if there is a difference between the minimum negative pressure value and the set negative pressure value, this difference may occur due to causes other than air leakage. For example, the suction circuit is generally provided with a one-way valve that releases positive pressure to protect the patient, but the suction circuit may not be completely sealed due to the structure of the one-way valve. In this case, even if no air leak occurs, a difference is generated between the minimum negative pressure value and the set negative pressure value. In addition, the difference may occur due to disturbance such as malfunction of the suction source or inflow of air from the connection part of the suction circuit. For this reason, if the presence or absence of air leak is determined only by the presence or absence of the difference between the minimum negative pressure value and the set negative pressure value, an erroneous determination may be caused.

  On the other hand, air leak is basically a phenomenon in which air leaks into the chest cavity when air is taken into the lungs during inhalation by the patient, but the air leak into the chest cavity is transmitted to the suction circuit as pressure fluctuations. Is when the patient exhales. Therefore, in order to determine the presence or absence of an air leak based on the pressure in the suction circuit, data at the time of expiration is required, and the presence or absence cannot be accurately determined only by the data at the time of inspiration. Therefore, in order to accurately determine the presence or absence of an air leak, it is preferable to determine within a time that can cover at least one breath (inspiration and expiration) of the patient.

  According to this aspect, when determining the presence or absence of air leak, based on whether or not the state where the difference between the minimum negative pressure value and the set negative pressure value is equal to or less than the threshold continues for the determination time or longer, the minimum negative pressure value and Considering not only the magnitude of the difference from the set negative pressure value, but also time. For this reason, it is possible to suppress an unclear determination result in which the opposite determination result is repeated, for example, it is determined that there is no air leak during inhalation while air leak is determined during expiration. Thereby, the reliability of the determination result of the presence or absence of air leak is increased. If the state where the difference between the minimum negative pressure value and the set negative pressure value is equal to or less than the threshold value continues for the determination time or longer, it can be determined that there is no air leak, and if this condition is not satisfied, it can be determined that there is an air leak.

  In one aspect of the second air leak monitoring apparatus of the present invention, the computing means calculates data fluctuation means (δNPmin) per predetermined time of the minimum negative pressure value as the minimum negative pressure related value (25 ), And the air leak determination means determines whether or not the air leak is present based on whether or not the state where the fluctuation range calculated by the data processing means is equal to or less than a threshold (Th2) continues for a determination time (JT2) or more. May be determined (claim 11). Also in this aspect, in determining whether or not there is an air leak, not only the magnitude of the fluctuation range per predetermined time of the minimum negative pressure value but also the time is taken into account, so the reliability of the determination result of whether or not there is an air leak is increased. When the state in which the fluctuation range of the minimum negative pressure value per predetermined time is equal to or less than the threshold value continues for the determination time or more, it can be determined that there is no air leak, and when this condition is not satisfied, it can be determined that there is air leak.

  The determination of the presence or absence of air leak may be performed from a viewpoint different from the determination based on the minimum negative pressure value. For example, in one aspect of the second air leak monitoring apparatus of the present invention, the suction circuit can store the gas in the thoracic cavity with the liquid (L) using the negative pressure generated by the suction source (5). Incorporated into the chest drain system (1B, 1C) for suction through the water sealed chamber (11, 41), the pressure measuring means measures the pressure between the suction source and the water sealed chamber. A bubble generation state acquisition means (30) for acquiring a bubble generation state in the water-sealed chamber, wherein the air leak determination means is based on the bubble generation state acquired by the bubble generation state acquisition means. The presence or absence of air leak may be determined (claim 12). According to this aspect, since the determination is based on the bubble generation state, the determination accuracy is improved with respect to the occurrence of air leak as described above. Therefore, in this case, since the determination based on the bubble generation state is performed in addition to the determination based on the minimum negative pressure value, the reliability of the determination result is improved. Further, in this aspect, the output control means, when the determination result based on the minimum negative pressure value or the minimum negative pressure related value regarding the presence or absence of the air leak is different from the determination result based on the bubble generation state, A determination result with air leak may be output to the output means as information relating to the determination result (claim 13). According to this, the determination result with air leak is preferentially output. That is, since the determination result without air leak is not output when the authenticity is unknown, safety is improved.

  In one aspect of the second air leak monitoring apparatus of the present invention, the calculation means includes the minimum negative pressure value as the minimum negative pressure related value and a set negative pressure (NPset) preset as a pressure in the suction circuit. ) Further includes data processing means (25) for calculating a difference (NPmin) from the value, and the air leak determination means is configured to reduce the air leak based on a temporal change in the difference calculated by the data processing means. It may be determined whether or not there is (claim 14). If the difference between the minimum negative pressure value and the set negative pressure value decreases with the passage of time, it can be estimated that the occurrence of air leaks is reduced during the decrease period without sequentially determining the presence or absence of air leaks. According to this aspect, since the temporal change in the difference between the minimum negative pressure value and the set negative pressure value is used as a reference, it can be determined whether or not the air leak tends to decrease.

  In one aspect of the second air leak monitoring apparatus of the present invention, the negative pressure calculating means calculates a maximum negative pressure value or a value near the maximum negative pressure based on the pressure measured by the pressure measuring means for each predetermined time. The output control means calculates the maximum negative pressure value calculated by the negative pressure calculation means or the maximum negative pressure related value (ΔNPmax, ΔNPpp) related to the maximum negative pressure value, as a value (NPmax). Each of the steps of the maximum negative pressure value (A to C) or the steps of the maximum negative pressure related value divided into a plurality of steps by the step dividing means (26a). Information (Irs) associated with the determination result (Rs) of the air leak determination means belonging to each stage of the maximum negative pressure value or each stage of the maximum negative pressure related value is output as information related to the determination result. You may make it output to a means (Claim 15).

  As described above, in the case of a patient being treated, it can be said that the maximum value of the negative pressure within a certain period is mainly caused by the patient's inspiration within that period. A patient's breathing changes the state of the inspiratory flow rate and intensity associated with breathing depending on the patient's situation, for example, resting, talking, and coughing. Therefore, the patient's situation can be associated with each stage by appropriately classifying the maximum negative pressure value or the maximum negative pressure related value with respect to the magnitude. According to this aspect, information in which each stage of the maximum negative pressure value or the maximum negative pressure related value is associated with the determination result regarding the presence or absence of air leak can be provided to the medical staff. Thereby, a medical worker in contact with the information can quickly know the relationship between the patient's situation and the occurrence of air leak. Therefore, it is not necessary for the medical staff to grasp the patient's situation based on the maximum negative pressure value or the maximum negative pressure-related value, so that the patient can be easily healed or the current state of the patient until the healing is achieved. I can grasp. Therefore, this aspect can provide meaningful information without imposing a burden on the medical staff when formulating a treatment policy.

  The maximum negative pressure related value may be a value related to the maximum negative pressure value. For example, the maximum negative pressure related value may be a difference (ΔNPpp) between the maximum negative pressure value and the minimum negative pressure value (Claim 16), or the maximum negative pressure related value may be the maximum negative pressure related value. It may be a difference (ΔNPmax) between a pressure value and a preset negative pressure value (NPset) preset as a pressure in the suction circuit (claim 17). Since these physical quantities also change in size according to the patient's situation, it is possible to associate each stage with the patient's situation by dividing these values according to the magnitude.

  In the second air leak monitoring apparatus, the calculation method of the minimum negative pressure value and the maximum negative pressure value, the significance of the value near the minimum value and the value near the maximum value, and the mode of the output means are also described in the first air leak monitor. It may be the same as in the case of the monitoring device.

  In the above description, in order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are added in parentheses, but the present invention is not limited to the illustrated form.

  As described above, according to the first air leak monitoring apparatus of the present invention, information closely related to the air leak state is output via the output means, which is useful for medical personnel to understand the air leak state. be able to. In addition, according to the second air leak monitoring apparatus of the present invention, since the determination result relating to the presence or absence of the air leak is output via the output means without the medical worker himself / herself determining whether or not the air leak exists, the treatment policy of the patient It can reduce the burden on medical staff required for formulation.

BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram which showed the outline of the chest cavity drain system containing the air leak monitoring apparatus which concerns on the 1st form of this invention. The block diagram which showed the detail of the air leak monitoring apparatus which concerns on a 1st form. The figure which showed an example of the image displayed on the screen of a display apparatus. The conceptual diagram which showed an example of the determination process of the generation tendency of an air leak. The figure which showed an example of the display of the display apparatus with which the information regarding an occurrence tendency was output. The conceptual diagram which showed the 1st example of the determination process of the presence or absence of an air leak. The conceptual diagram which showed the 2nd example of the determination process of the presence or absence of an air leak. The conceptual diagram which showed the 3rd example of the determination process of the presence or absence of an air leak. The conceptual diagram which showed the 4th example of the determination process of the presence or absence of an air leak. The figure which showed an example of the display of the display apparatus with which the information regarding a determination result was output. The functional block diagram explaining the process which performs the stage division | segmentation according to the patient's condition. The figure which showed an example of the display of the display apparatus from which the processing result of FIG. 11 was output. The whole block diagram which showed the outline of the chest cavity drain system containing the air leak monitoring apparatus which concerns on the 2nd form of this invention. The block diagram which showed the detail of the air leak monitoring apparatus which concerns on a 2nd form. The figure which showed an example of the display of the display apparatus in which the information regarding the bubble generation state was output. The whole block diagram which showed the outline of the chest cavity drain system containing the air leak monitoring apparatus which concerns on the 3rd form of this invention.

(First form)
As shown in FIG. 1, the thoracic drain system 1 </ b> A is used to discharge body fluid such as air leaking into a patient's thoracic cavity and blood accumulated in the thoracic cavity. The chest drain system 1A incorporates a suction circuit 2 connected to the chest cavity of a patient after thoracic surgery or a patient undergoing pneumothorax treatment. The suction circuit 2 includes a drain tube 3 placed in a chest cavity of a patient (not shown), and the drain tube 3 is connected to a chest drain device 4 that collects body fluid. An aspirator 5 as a suction source is connected to the chest drain device 4 via a suction passage 6 constituting a part of the suction circuit 2. The suction device 5 includes a suction pump (not shown) and its drive source. An air leak monitoring device 7 is applied to the suction circuit 2. The air leak monitoring device 7 is configured by storing various elements in a housing (not shown), but the appearance is not shown for convenience.

  The thoracic drain device 4 is connected to the drain tube 3 to store the drainage liquid Ld discharged from the chest cavity of the patient, and the water seals to the drainage storage chamber 10 and the suction passage 6 respectively. A chamber 11 and a pressure regulating chamber 12 connected to the suction passage 6 are provided. The water sealing chamber 11 contains a liquid L such as water and prevents backflow of outside air to the chest cavity side. The pressure regulating chamber 12 communicates with the atmosphere Ar and is filled with the liquid L to prevent suction due to excessive negative pressure.

  According to the chest drain system 1A, the negative pressure generated by the aspirator 5 traps the liquid in the patient's chest cavity in the drainage chamber 10 of the chest drain device 4 as indicated by the solid line arrow, and also in the patient's chest cavity. The gas leaked into the pipe is guided to the suction passage 6 through the water seal chamber 11 as indicated by the broken arrow. When an air leak occurs in the chest cavity of the patient, the leaked gas passes through the water seal chamber 11 of the chest drain device 4, so that bubbles are generated in the water seal chamber 11. In order to adjust the pressure of the suction circuit 2, the atmosphere Ar may be guided to the suction passage 6 through the pressure regulating chamber 12 as indicated by a one-dot chain line arrow.

  The air leak monitoring device 7 is a pressure sensor 15 as pressure measuring means connected to the branch path 6a branched from the suction passage 6, and an arithmetic means that is electrically connected to the pressure sensor 15 and performs various information processing. Control unit 16, display device 17 as an output means for displaying information output from control unit 16, and operations for accepting operations of users such as medical workers and inputting various operation commands to control unit 16 And a unit 18. Since the branch path 6 a to which the pressure sensor 15 is connected branches off from the suction passage 6 between the suction device 5 and the water seal chamber 11, the pressure sensor 15 is a pressure between the suction device 5 and the water seal chamber 11. Can be measured.

  As shown in FIG. 2, the control unit 16 is configured as a computer, and the illustrated units are logically configured by executing a predetermined program. However, each of the timer 21 and the storage unit 22 is configured by being coupled to an electronic circuit (not shown) included in the control unit 16 and a physical device such as a storage device such as a RAM and a ROM, and the remaining units are controlled. It is logically configured in a microprocessor (not shown) included in the unit 16. Among the units configured in the control unit 16, the negative pressure calculation unit 20 is a negative pressure calculation unit according to the present invention, the data processing unit 25 is a data processing unit according to the present invention, and the output control unit 26 is according to the present invention. The air leak determination unit 27 corresponds to the output control means and corresponds to the air leak determination means according to the present invention.

  The pressure measurement value Mv of the pressure sensor 15 is input to the negative pressure calculation unit 20. The negative pressure calculation unit 20 extracts a plurality of measurement values Mv for a predetermined time, for example, 60 seconds while referring to the counter value C supplied from the timer 21 at a constant time interval, and extracts the extracted data D as a counter value. Sequentially stored in the storage unit 22 while being associated with C. In the data extraction performed by the negative pressure calculation unit 20, the measurement value Mv input from the pressure sensor 15 is used as it is, but an average value (for example, a moving average value) of several measurement values Mv is measured as one measurement. As a value, a plurality of measured values can be extracted in a predetermined time.

  The negative pressure calculation unit 20 reads the extraction data D from the storage unit 22 and calculates the minimum negative pressure value NPmin and the maximum negative pressure value NPmax from the extraction data D. The negative pressure calculation unit 20 calculates the minimum value of the extraction data D or a value in the vicinity thereof as the minimum negative pressure value NPmin, and calculates the maximum value of the extraction data D or a value in the vicinity thereof as the maximum negative pressure value NPmax. The value is sent to the data processing unit 25. The nearby value is a value within the range where there is no problem even if it is handled as the minimum value or the maximum value of the negative pressure, and the range is appropriately determined in consideration of the data extraction time (predetermined time). Good. In short, only true minimum and maximum values are not subject to processing.

The data processing unit 25 associates each of the minimum negative pressure value NPmin and the maximum negative pressure value NPmax sequentially sent from the negative pressure calculation unit 20 with time while referring to the counter value C. Further, the data processing unit 25 calculates the following various physical quantities (1) to (4) based on the minimum negative pressure value NPmin and the maximum negative pressure value NPmax sequentially sent from the negative pressure calculation unit 20, Each physical quantity is associated with time while referring to the counter value C.
(1) Difference ΔNPmin between minimum negative pressure value NPmin and set negative pressure value NPset
(2) Fluctuation width δNPmin per predetermined time of the minimum negative pressure value NPmin
(3) Difference ΔNPmax between maximum negative pressure value NPmax and set negative pressure value NPset
(4) Difference ΔNPpp between maximum negative pressure value NPmax and minimum negative pressure value NPmin

  The set negative pressure value NPset is a negative pressure value set in advance as the pressure in the suction circuit 2 and is stored in the storage unit 22. The data processing unit 25 reads the set negative pressure value NPset from the storage unit 22 and uses it for calculating the physical quantity. Further, the fluctuation range δNPmin of (2) is the data processing unit 25 when the data of the minimum negative pressure value NPmin sent from the negative pressure processing unit 20 is collected to some extent, for example, when 300 seconds of data are collected. Is calculated by In this case, 300 seconds corresponds to the predetermined time.

  The data processing unit 25 outputs the minimum negative pressure value NPmin and the maximum negative pressure value NPmax associated with the time and the physical quantities (1) to (4) associated with the time to the output control unit 26 and the air leak. The data is sent to each determination unit 27. Detailed processing contents in the air leak determination unit 27 will be described later.

  The output control unit 26 expresses various physical quantities associated with the time sent from the data processing unit 25 as a graph with the horizontal axis representing time and the vertical axis representing negative pressure. Are converted into drawing data Imd... For each physical quantity, and the drawing data Imd... Are temporarily stored in the storage unit 22. Then, the output control unit 26 reads drawing data Imd corresponding to the selected display mode from the storage unit 22 in accordance with a display mode selection command Cm described later input from the operation unit 18, and the drawing data Imd is displayed on the display device. The display device 17 is controlled so as to be output to the 17 screen 17a.

  Various drawing data Imd... Are associated with time. Therefore, among the images displayed as information on the screen 17a, those in which the minimum negative pressure value NPmin and time are associated with each other are added to the minimum negative pressure information Imin, the difference ΔNPmin in (1), and the above (2). The correspondence between the fluctuation range δNPmin and time corresponds to the minimum negative pressure related information RImin related to the minimum negative pressure information Imin. Of these images, those in which the maximum negative pressure value NPmax and time are associated with each other correspond to the maximum negative pressure information Imax and the difference ΔNPmax in (3) and the difference ΔNPpp in (4) correspond to time. The attached information corresponds to the maximum negative pressure related information RImax related to the maximum negative pressure information Imax.

  The air leak monitoring device 7 is provided with a plurality of types of display modes for causing the display device 17 to display images relating to various physical quantities individually or in a state where two or more physical quantities are combined. For example, as a mode for displaying a physical quantity on the display device 17, (a) a display mode for displaying a time change of the minimum negative pressure value NPmin, (b) a display mode for displaying a time change of the maximum negative pressure value NPmax, (c ) Display mode for displaying the difference ΔNPmin between the minimum negative pressure value NPmin and the set negative pressure value NPset, (d) Display mode for displaying the difference ΔNPmax between the maximum negative pressure value NPmax and the set negative pressure value NPset, (e) Maximum There is a display mode for displaying a difference ΔNPpp between the negative pressure value NPmax and the minimum negative pressure value NPmin. There are also multiple types of display modes in which these physical quantities are displayed individually and simultaneously on the screen 17a of the display device 17 as a graph.

  The operation unit 18 is configured to accept an operation for selecting these display modes as necessary. The operation unit 18 outputs a selection command Cm corresponding to each display mode in response to a user operation, and the selection command Cm output from the operation unit 18 is input to the output control unit 26. The output control unit 26 performs the process of selecting the display mode described above according to the selection command Cm.

  A display example of the display device 17 is shown in FIG. In the image of FIG. 3, each time change of the maximum negative pressure value NPmax, the minimum negative pressure value NPmin, and the set negative pressure value NPset is expressed simultaneously. “0” on the horizontal axis means the present, and “−” means the past. This display scale is set so that data for the past 20 hours can be displayed. The scale of the time axis and each scale of the negative pressure axis can be appropriately changed according to the user's operation. A medical worker such as a doctor who sees the display of FIG. 3 can grasp the patient's progress and the air leak state in the past 20 hours using each displayed physical quantity as a clue.

  The display of FIG. 3 includes the minimum negative pressure information Imin, and this minimum negative pressure information Imin includes the time change of the minimum negative pressure value NPmin that is closely related to the air leak state of the patient. The person can grasp the magnitude of the minimum negative pressure value NPmin and determine whether or not there is an air leak, that is, whether or not an air leak has occurred. Further, since the minimum negative pressure information Imin is obtained by associating the minimum negative pressure value NPmin with the time, it is possible to specify the occurrence point of the air leak along with the time change. As the air leak occurs, the minimum negative pressure value NPmin is lower than the set negative pressure value NPset, that is, the difference ΔNPmin increases. In the display of FIG. 3, the set negative pressure value NPset is also shown, so that the temporal change of the difference ΔNPmin can be easily grasped visually. Therefore, the medical staff can determine whether the air leak is likely to occur, that is, whether the air leak is increasing or decreasing.

  Note that, instead of the minimum negative pressure information Imin displayed in FIG. 3, only the minimum negative pressure related information RImin such as the difference ΔNPmin in (1) and the fluctuation range δNPmin in (2) is displayed. Even when is switched, the minimum negative pressure related information RImin is useful for grasping the state of the presence or absence of an air leak, the occurrence tendency, and the like by the medical staff in the same manner as the minimum negative pressure information Imin. That is, it is possible to make the same determination as when the medical staff acquires the minimum negative pressure information Imin. In particular, since the medical worker can directly acquire the difference ΔNPmin and its temporal change in (1) above, only the minimum negative pressure information Imin is displayed which is a burden required for the medical worker to grasp the state of the air leak. This is less than if Further, the larger the fluctuation range δNPmin of (2) above, the stronger the occurrence of air leak is estimated. Therefore, by displaying the temporal change of the fluctuation range δNPmin as the minimum negative pressure related information RI, for example, when the medical worker grasps that the period in which the fluctuation range δNPmin is small continues for a long time, It can be estimated that no air leak occurred. That is, it can be used for the judgment of the presence or absence of an air leak by a medical staff.

  In addition, since the display of FIG. 3 includes the time variation of the maximum negative pressure value NPmax, which is the maximum negative pressure information Imax, the patient's situation (at rest, conversation or (When coughing) can be grasped, and the situation of the patient and the state of occurrence of air leak can be correlated and grasped. That is, the maximum negative pressure information Imax can be used to determine whether the air leak occurred at rest, occurred during conversation, or occurred during coughing. For example, the display in FIG. 3 formulates a treatment policy, such as when a medical worker knows that the patient is close to healing when he knows that an air leak does not occur at rest or during conversation but occurs only during coughing. Therefore, more meaningful information can be provided to the medical staff.

  Even when the display mode is switched to display the maximum negative pressure related information RImax related thereto instead of the maximum negative pressure information Imax included in the display of FIG. 3, the difference ΔNPmax in the above (3) or the above The maximum negative pressure related information RImax in which the physical quantity such as the difference ΔNPpp of (4) is associated with time can be used in the same manner as the maximum negative pressure information Imax in order to grasp the patient's situation. Even when the display mode is switched in this way, the maximum negative pressure related information RImax displayed instead is useful as meaningful information for the medical staff to formulate a treatment policy.

  Next, returning to FIG. 2, the determination process performed by the air leak determination unit 27 of the control unit 16 and the output of the determination result will be described with reference to FIGS. 2 and 4 to 12. The determination processing performed by the air leak determination unit 27 is classified into (α) determination of occurrence tendency of air leak and (β) determination of presence / absence of air leak.

(Α) Determination of air leak occurrence tendency This determination method determines whether or not the occurrence of air leak tends to decrease. As described above, if the difference ΔNPmin between the minimum negative pressure value NPmin and the set negative pressure value NPset decreases with the passage of time, the occurrence of air leaks occurs during the decrease period even if the presence or absence of air leaks is not sequentially determined. It can be guessed that it is decreasing. This determination method is based on this consideration and is a method for determining whether or not the air leak tends to decrease on the basis of the difference ΔNPmin between the minimum negative pressure value NPmin and the set negative pressure value NPset.

  An example of this determination method will be described with reference to FIGS. For example, the air leak determination unit 27 extracts data Δ1, Δ2,... Every about 1 to 2 hours (every 2 hours in the illustrated example) from the difference ΔNPmin obtained from the data processing unit 25 (FIG. 4). . Then, the data adjacent to each other are compared to specify the magnitude relationship between them. When the magnitude relationship is specified in this way, it is possible to determine a general tendency of air leaks with time. In the case of FIG. 4, although there are some exceptions, the difference ΔNPmin gradually decreases, and it can be determined that the air leak tends to decrease when viewed over a span of 20 hours.

  In this embodiment, when the air leak determination unit 27 receives an operation command Cmb of a user who desires to display the determination result, the air leak determination unit 27 synchronizes the above-described adjacent data magnitude determination result Rs1 with the display data to the output control unit 26. send. Moreover, the air leak determination part 27 memorize | stores the determination result Rs1 in the memory | storage part 22 in the state matched with time irrespective of the presence or absence of the operation command Cmb.

  The output control unit 26 displays information Irs regarding the magnitude relation determination result Rs1 on the screen 17a together with physical quantity information such as minimum negative pressure information Imin and minimum negative pressure related information RImin corresponding to the display mode selected by the user. The display device 17 is controlled as described above. An example of the display is shown in FIG. In the illustrated example, the information Irs related to the determination result Rs1 is encoded into a symbol S meaning increase or decrease, and the symbol S is superimposed on the display of the display mode selected by the user (for example, FIG. 3). Displayed on the screen 17a. Thereby, the medical staff who looked at the display of FIG. 5 can grasp | ascertain the occurrence tendency of an air leak directly. Therefore, the medical staff can know the tendency of the occurrence of air leak without judging himself / herself, thereby reducing the burden required for formulating a treatment policy for the patient.

(Β) Determination of presence or absence of air leak This determination method is common based on the minimum negative pressure value NPmin that is closely related to the state of air leak, but the physical quantities used for final determination are different from each other in the following ( There are two methods i) and (ii).

(I) Method using difference ΔNPmin between minimum negative pressure value NPmin and set negative pressure value NPset As shown in FIGS. 6 and 7, this method is a difference ΔNPmin between minimum negative pressure value NPmin and set negative pressure value NPset. Whether or not there is an air leak is determined based on whether or not the state where the value is equal to or less than the threshold Th1 continues for the determination time JT1 or more. The basic concept of this determination method will be described with reference to FIGS. FIG. 6 shows an example in which the determination time JT1 is a relatively long time (for example, 6 hours). As shown in FIG. 6, the period in which the state in which the minimum negative pressure value NPmin is equal to or less than the threshold Th1 continues for the determination time JT1 or longer is a period from time t0 to time t1. During this period, it is determined that “no air leak”. On the other hand, it is determined that “there is an air leak” during the period from time t1 to time t2 that does not meet this criterion. Thus, since the fact that there is no air leak for a long time is found by setting the determination time JT1 to be relatively long, the patient is healed by outputting the information on the determination result to the display device 17 as described later. Useful for determining the final stage of the process.

  In contrast to FIG. 6, FIG. 7 shows an example in which the determination time JT1 is set to a relatively short time (for example, several seconds that can cover one breath). In the case of FIG. 7, even if the same data and the same threshold value Th1 as in FIG. 6, the determination result is different from that in FIG. That is, the determination result of “no air leak” exists even in the period (time t1 to t2) in which it is determined that “there is air leak” by the method of FIG. By setting the determination time JT1 to a relatively short time as in the case of FIG. 7, a detailed determination result regarding the presence or absence of air leak can be obtained. Therefore, by outputting information related to the determination result to the display device 17 as will be described later, it can be used to grasp the state of the air leak in more detail. In addition, the number of times that “air leak” is determined is counted every unit time (for example, every hour), and the number of determinations “air leak” per unit time is output to the display device 17 as information Irs related to the determination result. Therefore, it is also possible to quantitatively show the transition of the patient's healing status.

(Ii) Method of using fluctuation range δNPmin of minimum negative pressure value NPmin In this method, as shown in FIGS. 8 and 9, the state in which fluctuation width δNPmin of minimum negative pressure value NPmin is equal to or less than threshold Th2 is equal to or longer than determination time JT2. The presence or absence of air leak is determined based on whether or not to continue. The basic concept of this determination method will be described with reference to FIGS. FIG. 8 is an example in which the determination time JT2 is set to a relatively long time (for example, 6 hours), and FIG. 9 is an example in which the determination time JT2 is set to a relatively short time (for example, several seconds that can cover one breath). . Similarly to the method (i), this determination method can grasp the fact that there is no air leak for a long time by increasing the determination time JT2 in FIG. 8, and by decreasing the determination time JT2 in FIG. A detailed determination result about the presence or absence of air leak can be obtained. In the case of FIG. 9 as well, as in FIG. 7 of (i) above, it is possible to quantitatively indicate the transition of the patient's healing status by counting and outputting the number of times determined as “air leak”. Become.

  Information on the determination result obtained by the determination method (i) or (ii) is output from the display device 17 as follows. As in the case of (α), the air leak determination unit 27 determines the determination result obtained by the determination method of (i) or (ii) when the operation command Cmb of the user who desires to display the determination result is received. Rs2 is sent to the output control unit 26. Moreover, the air leak determination part 27 memorize | stores the determination result Rs2 in the memory | storage part 22 in the state matched with time irrespective of the presence or absence of the operation command Cmb.

  The output control unit 26 displays the information Irs related to the determination result Rs2 on the screen 17a together with the physical quantity information such as the minimum negative pressure information Imin and the minimum negative pressure related information RImin corresponding to the selected display mode. 17 is controlled. An example of the display is shown in FIG. In the illustrated example, the information Irs related to the determination result Rs2 is symbolized by an indicator Ind that means “with air leak” or “without air leak”, and the symbolized indicator Ind is displayed in the display mode selected by the user ( For example, it is displayed on the screen 17a in a state of being superimposed on FIG. The display of the indicator Ind shown in FIG. 10 is a display of information Irs regarding the determination result of FIG.

  The methods (i) and (ii) both consider not only the magnitude of the physical quantity but also the determination time. Therefore, by changing the determination time according to the purpose, more meaningful information can be given to the medical staff. Can be provided. The reason for considering the determination time is as described above.

  The determination result Rs2 regarding the presence or absence of air leak can be displayed by the following method in addition to the display method as shown in FIG. As described above, since the maximum negative pressure value NPmax varies depending on the patient's situation (resting, speaking, coughing, etc.), the difference ΔNPmax between the maximum negative pressure value NPmax and the set negative pressure value NPset, The difference ΔNPpp between the pressure value NPmax and the minimum negative pressure value NPmin also changes in the same tendency as the maximum negative pressure value NPmax. Since these physical quantities ΔNPmax and ΔNPpp are related to the maximum negative pressure value NPmax as described above, these physical quantities ΔNPmax and ΔNPpp may be collectively referred to as a maximum negative pressure related value RNPmax for convenience.

  In this output method, the maximum negative pressure value NPmax or the maximum negative pressure related value RNPmax is divided into a plurality of stages with respect to the magnitude, each of the maximum negative pressure value NPmax or the maximum negative pressure related value RNPmax divided into a plurality of stages, The display device 17 is caused to output information in association with the determination result regarding the presence or absence of air leaks belonging to the stage.

  FIG. 11 shows the logical configuration of the output control unit 26 in detail. The stage division unit 26a logically configured in the output control unit 26 corresponds to the stage division unit according to the present invention. Stage division by the stage division unit 26a includes the following three methods (x), (y), and (z) depending on the target physical quantity.

(X) Method of grading the maximum negative pressure value NPmax The grading unit 26a is configured so that the maximum negative pressure value NPmax corresponds to each of rest, conversation, and cough, for example, A: less than 20 hPa, B: It is divided into three stages of 20 hPa or more and less than 30 hPa and C: 30 hPa or more.

  The stage division unit 26a distributes the data to the respective stages A to C by searching for data related to the determination result Rs2 about the presence or absence of air leak stored in the storage unit 22 (S1). As described above, since the determination result Rs2 is stored in the storage unit 22 in a state associated with time, the data distributed to the stages A to C can be classified for each predetermined period. Therefore, the stage division unit 26a divides the data distributed to the respective stages A to C, for example, every 24 hours, and determines whether or not “air leak exists” data exists for each of the sections 1, 2,. (S2). Then, the stage division unit 26a generates information Iyn in which “with air leak” or “without air leak” is specified for each of the stages A to C based on the determination (S3).

  The output control unit 26 converts the information Iyn generated by the stage division unit 26a into drawing data corresponding to an image in a chart format, and then displays the information Irs regarding the determination result on the screen 17a of the display device 17. An example in which an image in a chart format is displayed on the screen 17a is shown in FIG. With the display of FIG. 12, the medical staff who sees the display can consider as follows. In other words, the first day was “needed to be air leaked” at all stages regardless of the patient's condition, but the second day was “needed to be air leaked” at stage B and stage C. It can be seen that in stage A, the patient's condition has improved due to “no air leak”. Furthermore, since the third day is “air leak” only at stage C, it can be seen that the patient's condition has improved from the second day. On the fourth day, since there is “no air leak” at all stages, it can be determined that the disease such as the patient's pneumothorax has been cured.

  As described above, the medical staff who has seen the display of FIG. 12 can easily grasp the process toward the healing of the patient without estimating the situation of the patient in which the air leak has occurred from the display of FIG. Therefore, it is possible to provide meaningful information without burdening the medical staff when formulating a treatment policy.

(Y) Method of grading the difference ΔNPmax In this method, the physical value used for grading is different from the above (x), and therefore the specific numerical range of grading is different. That is, in this method, similarly to the above (x), the difference ΔNPmax is set to, for example, A: less than 10 hPa, B: 10 hPa or more and less than 20 hPa, so as to correspond to each of the patient's rest, conversation, and cough. : Divide into 3 stages of 20 hPa or more. The specific data distribution process and the information display process and the significance of the display are the same as in the above (x), and the description thereof will be omitted.

(Z) Method of grading difference ΔNPpp This method is the same as (x) except for the specific numerical range of grading. That is, in this method, the difference ΔNpp is divided into three stages of A: less than 10 hPa, B: 10 hPa or more and less than 20 hPa, and C: 20 hPa or more so as to correspond to each of the patient's rest, conversation, and cough. This method also has the same significance as the above (x) because of the specific data distribution process, information display process, and display, and a description thereof will be omitted.

(Second form)
Next, a second embodiment of the present invention will be described with reference to FIGS. The second mode is characterized in that the information related to the generation state of bubbles generated in the water seal chamber 11 of the chest drain device 4 described above is supplementarily used for the above-described output or air leak determination process. . Since points other than this are the same as in the first embodiment, description of matters common to the first embodiment is omitted below.

  As shown in FIG. 13, the chest cavity drain system 1 </ b> B includes an optical sensor 30 as a bubble generation state acquisition unit provided in the water seal chamber 11 of the chest cavity drain device 4. As described above, the chest drain device 4 has been known to generate bubbles in the water seal chamber 11 with the occurrence of air leaks. By detecting the generation of the bubbles, it is possible to make a reliable air leak determination. Although the illustration is simplified, the optical sensor 30 irradiates the inspection light from the outside of the transparent water-sealed chamber 11, and the water-sealed due to the change in the light intensity of the transmitted light transmitted through the water-sealed chamber 11 or the reflected light reflected. The presence or absence (bubble generation state) of bubbles in the chamber 11 can be acquired. A signal output from the optical sensor 30 is input to the control unit 16 of the air leak monitoring device 7.

  Since this embodiment processes an input signal from the optical sensor 30, the logical configuration of the control unit 16 and the processing content of each component are slightly different from those of the first embodiment. In the following, differences between the logical configuration and processing of the control unit 16 will be described.

  As shown in FIG. 14, the bubble detection signal Sga from the optical sensor 30 is input to the bubble counting processing unit 31. The bubble counting processing unit 31 associates the detection signal Sga with time by referring to the counter value C supplied by the timer 21. The bubble counting processing unit 31 processes the detection signal Sga associated with the time into detection data, analyzes the detection data, and calculates the number of generated bubbles Na, the bubble generation duration Ta, and the bubble flow rate Fa, respectively. To the data processing unit 25. The generated number Na means the number of bubbles generated per predetermined time (for example, 10 seconds). The bubble generation duration Ta defines a phenomenon in which bubbles are continuously generated at relatively short intervals as one event, and means the duration of one event. The bubble flow rate Fa is estimated from the bubble generation duration Ta and is a physical quantity corresponding to the number of bubbles per unit time generated in the event. The bubble generation number Na, the bubble generation duration Ta, or the flow rate Fa corresponds to information related to the bubble generation state.

  The data processing unit 25 synchronizes each of the generated number Na, the generation duration Ta, and the flow rate Fa sequentially sent from the bubble counting processing unit 31 with the various physical quantities NPmin, ΔNPmin, NPmax, etc. described in the first embodiment. To the output control unit 26 and the air leak determination unit 27.

  The output control unit 26 appropriately converts the information on the generated number Na, the generation duration Ta, and the flow rate Fa into the drawing data Imd... In the same manner as the display of the various physical quantities described above, and the drawing data Imd is displayed on the display device 17. The display device 17 is controlled so as to be output to the screen 17a. An example in which this image is displayed on the screen 17a is shown in FIG. In the image of FIG. 15, information such as the number of generated bubbles Na is processed into the visual information Io and superimposed on the display of FIG. Since the visual information Io in the figure is information in which the generation of bubbles is represented in a graphic form, a medical worker in contact with the image in FIG. 15 simply has information such as the number of bubbles generated Na, the generation duration Ta, and the flow rate Fa. Compared to the case indicated by numerical values, it is possible to grasp the bubble generation state intuitively. Further, since the visual information Io is displayed together with the minimum negative pressure information Imin and the maximum negative pressure information Imax, the accuracy of judgment for grasping the air leak state and the patient situation is improved.

  The operation unit 18 is configured to be able to accept an operation for switching display or non-display of the visual information Io related to bubbles, and outputs a selection command Cm corresponding to display or non-display in response to a user operation. The selection command Cm output from 18 is input to the output control unit 26. The output control unit 26 performs the above-described processing according to the selection command Cm.

  The air leak determination unit 27 uses the information regarding the number of generated bubbles Na, the generation duration Ta, and the flow rate Fa sent from the data processing unit 25 to increase the determination accuracy in the various determinations described in the first embodiment. To implement. The information such as the number of generated bubbles Na is based on the detection data of the bubbles generated in the water sealed chamber 11 and can be said to be highly reliable. When various physical quantities ΔNPmin and the like that are the basis of the determination result of “no air leak” by the air leak determination unit 27 and the information such as the number of bubbles generated Na are synchronized, the fact that an air leak has actually occurred. However, there is a possibility of making an erroneous determination of “no air leak”. Therefore, the air leak determination unit 27 gives priority to information such as the number of generated bubbles Na and changes the determination result Rs2 from “no air leak” to “with air leak” and sends it to the output control unit 26. Then, the output control unit 26 causes the display device 17 to output the changed determination result Rs2 by the various methods described above.

  The contents of processing performed by the air leak determination unit 27 and the output control unit 26 can be paraphrased as follows. That is, the air leak determination unit 27 determines the presence or absence of air leak based on the bubble generation state, and the output control unit 26 determines the air leak based on the determination result based on the bubble generation state by the air leak determination unit 27 and various physical quantities ΔNPmin. In other words, when the presence / absence determination result is different, it can be said that the determination result of “air leak” is preferentially output to the display device 17. Therefore, since the determination based on the bubble generation state is performed in addition to the determination based on various physical quantities ΔNPmin and the like, the reliability of the determination result is improved. Moreover, since the determination result with air leak is prioritized, safety is improved.

(Third form)
Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment of the chest drain system 1C incorporates a suction circuit 32 connected to the chest cavity of a patient after thoracic surgery or during treatment of a pneumothorax. The suction circuit 32 includes a drain tube 33 placed in a chest cavity of a patient (not shown), and the drain tube 33 is connected to a drain bag 34 for collecting body fluid. An electric low pressure suction device 35 is connected to the drain bag 34 through a suction passage 36 that constitutes a part of the suction circuit 32. The drain bag 34 communicates with the drain tube 33 to store the drainage liquid Ld drained from the chest cavity of the patient, and the water sealing chamber 41 communicated with each of the drainage storage chamber 40 and the suction passage 36. And. The water sealing chamber 41 contains a liquid L such as water and prevents backflow of outside air to the chest cavity side.

  The electric low pressure suction device 35 includes a suction pump 38 as a suction source. The suction pump 38 is connected to the suction passage 36 and controlled in operation by the air leak monitoring device 7 described above. That is, the air leak monitoring device 7 of this embodiment has a function of controlling the suction pump 38 in addition to the above-described air leak monitoring function. The electric low-pressure suction device 35 is provided with a function of preventing suction due to excessive negative pressure and issuing an alarm, but this function does not hinder the air leak monitoring function. The suction passage 36 is branched inside the electric low pressure suction device 35, and the pressure sensor 15 of the air leak monitoring device 7 is connected to the branch passage 36a. Therefore, it can be said that the air leak monitoring device 7 is applied to the suction circuit 32. Since the branch path 36 a to which the pressure sensor 15 is connected branches off from the suction passage 36 between the suction pump 38 and the water seal chamber 41, the pressure sensor 15 is a pressure between the suction pump 38 and the water seal chamber 11. Can be measured. The control unit 16 of the air leak monitoring device 7 feedback-controls the suction pump 38 so that the deviation between the measured value measured by the pressure sensor 15 and the set negative pressure value NPset described above is eliminated. Thereby, the pressure in the suction circuit 32 is controlled to the set negative pressure value NPset.

  The operation unit 18 of the air leak monitoring device 7 is provided with a function of accepting a power-on operation of the electric low-pressure suction device 35 by the user and a setting operation for setting the set negative pressure value NPset. The control unit 16 controls the operation of the suction pump 38 in response to a user power-on operation on the operation unit 18.

  According to the chest drain system 1C, the liquid in the patient's chest cavity is transferred to the drain chamber 40 of the drain bag 34 by the negative pressure generated by the suction pump 38 provided in the electric low-pressure suction device 35, as indicated by the solid line arrow. The gas that has been trapped and leaked into the chest cavity of the patient is guided to the suction passage 36 via the water seal chamber 41 as indicated by the dashed arrow. When an air leak occurs in the chest cavity of the patient, the leaked gas passes through the water sealing chamber 41 of the drain bag 34, so that bubbles are generated in the water sealing chamber 41. Since the air leak monitoring function provided in the air leak monitoring device 7 of the present embodiment is the same as that of the first embodiment, the description thereof is omitted. In addition, it is also possible to attach the optical sensor 30 used in the second form to the chest drain system 1C and perform the processing described in the second form.

(Other forms)
The present invention is not limited to the above embodiments, and can be implemented in various forms within the scope of the gist of the present invention. The physical configuration of each of the above forms is only an example. Basically, the pressure measuring means may be provided at any location in the suction circuit as long as it is applied to the suction circuit connected to the chest cavity of the patient.

  In each of the above embodiments, as shown in FIG. 2 or FIG. 14, the control unit 16 gives the display device 17 the minimum negative pressure information Imin, the minimum negative pressure related information RImin, the maximum negative pressure information Imax, and the maximum negative pressure. Related information RImax, visual information Io on air bubbles, and information Irs on air leak determination results can be output individually by switching the display mode, or can be output on a single screen by combining these alone or in combination of two or more. Yes. However, the specific examples of output introduced in the above description are only some of these output variations. Therefore, the air leak monitoring apparatus of the present invention can be implemented in such a form that, for example, only the minimum negative pressure information Imin is output among these pieces of information. If the information to be output is limited in this way, it is sufficient to calculate only the physical quantity necessary for generating the limited information and handle the calculation result. In short, it is not necessary to output all of the information and it is not necessary to generate all of the information. The information may be selected and generated and output as appropriate.

  In each of the above embodiments, not only information Imin related to the physical quantity, but also information Irs related to the determination result is output. However, the present invention may be implemented in a form in which information related to the air leak determination result is not output. it can. Such a form can be easily realized by changing to a form in which the process of the air leak determination unit 27 and the process for the air leak determination unit 27 implemented in the control unit 16 of each form are removed. In this case, the judgment and evaluation regarding the state of the air leak are left to the medical staff who grasps the output information, but the judgment and evaluation can be aided by outputting various information. Conversely, the present invention can also be implemented in a form in which only information Irs related to the determination result is output without outputting information Imin related to the physical quantity. In this case, a medical worker in contact with the information can directly know information regarding the determination result of the air leak.

  In each of the above embodiments, each information is output by displaying an image on the display device 17, but displaying the image is only an example. As described above, a printing device that outputs information to a medium such as paper or a speaker that outputs information as audio information may be used as the output means. For example, after displaying a part of various information as an image, It is also possible to implement the present invention in such a manner that a part is output as audio information from a speaker or printed on a medium such as paper.

  In the second embodiment, the bubble generation state is acquired directly by the optical sensor 30 that is attached to the water-sealed chamber (see FIG. 13). For example, it is described in Patent Document 1 described above. According to the method described above, it is also possible to acquire the bubble generation state by grasping the pressure change accompanying the bubble generation from the measurement result of the pressure measuring means. In this case, there is an advantage that the number of parts can be reduced because a device such as an optical sensor is not required. Instead of the optical sensor 30, a flow sensor that can measure the flow rate of the fluid can also be used as the bubble generation state acquisition unit.

1A-1C Thoracic drain system 2, 32 Suction circuit 5 Aspirator (suction source)
7 Air leak monitoring device 11, 41 Water seal chamber 15 Pressure sensor (pressure measuring means)
16 Control unit (calculation means)
17 Display device (output means)
20 Negative pressure calculation part (negative pressure calculation means)
25 Data processing unit (data processing means)
26 Output control unit (output control means)
26a Stage division unit (stage division means)
30 Optical sensor (bubble generation state acquisition means)
38 Suction pump (suction source)
NPmin Minimum negative pressure value Imin Minimum negative pressure information RImin Minimum negative pressure related information

Claims (17)

An air leak monitoring device applied to a suction circuit connected in the chest cavity of a patient,
Pressure measuring means for measuring the pressure in the suction circuit;
Output means capable of outputting predetermined information;
A computing means for performing computation using the pressure measured by the pressure measuring means;
With
The computing means is
A negative pressure calculating means for calculating a minimum negative pressure value or a value in the vicinity thereof as a minimum negative pressure value based on the pressure measured every predetermined time measured by the pressure measuring means;
Output that causes the output means to output at least one of the minimum negative pressure information in which the minimum negative pressure value calculated by the negative pressure calculation means is associated with the time or the minimum negative pressure related information related to the minimum negative pressure information Control means,
An air leak monitoring device.   The air leak monitoring device according to claim 1, wherein the output control means causes the output means to output a set negative pressure value preset as a pressure in the suction circuit together with the minimum negative pressure information.   The minimum negative pressure related information is information in which the difference between the minimum negative pressure value and a set negative pressure value preset as a pressure in the suction circuit is associated with time. Air leak monitoring device.   The air leak monitoring apparatus according to claim 1, wherein the minimum negative pressure related information is information in which a fluctuation range per predetermined time of the minimum negative pressure value calculated by the negative pressure calculation unit is associated with a time. The negative pressure calculating means calculates a maximum value of negative pressure or a value in the vicinity thereof as a maximum negative pressure value based on the pressure every predetermined time measured by the pressure measuring means,
The output control means outputs maximum negative pressure information associated with the maximum negative pressure value calculated by the negative pressure calculation means and time, or maximum negative pressure related information related to the maximum negative pressure information, as the minimum negative pressure. The air leak monitoring apparatus according to any one of claims 1 to 4, wherein the output unit outputs the pressure information together with at least one of pressure information and the minimum negative pressure related information.   The air leak monitoring apparatus according to claim 5, wherein the maximum negative pressure related information is information in which a difference between the maximum negative pressure value and the minimum negative pressure value is associated with time.   The maximum negative pressure related information is information in which a difference between the maximum negative pressure value and a set negative pressure value preset as a pressure in the suction circuit is associated with time. Air leak monitoring device. The suction circuit is incorporated in a thoracic drain system that sucks the gas in the thoracic cavity through a water-sealed chamber containing a liquid by using a negative pressure generated by a suction source;
The pressure measuring means measures a pressure between the suction source and the water seal chamber,
Further comprising bubble generation state acquisition means for acquiring a bubble generation state in the water seal chamber;
The output control means includes information related to the bubble generation state acquired by the bubble generation state acquisition means together with at least one of the minimum negative pressure information and the minimum negative pressure related information in a state associated with time. The air leak monitoring apparatus according to any one of claims 1 to 4, wherein the air leak monitoring apparatus outputs the output means. An air leak monitoring device applied to a suction circuit connected in the chest cavity of a patient,
Pressure measuring means for measuring the pressure in the suction circuit;
Output means capable of outputting predetermined information;
A computing means for performing computation using the pressure measured by the pressure measuring means;
With
The computing means is
A negative pressure calculating means for calculating a minimum negative pressure value or a value in the vicinity thereof as a minimum negative pressure value based on the pressure measured every predetermined time measured by the pressure measuring means;
Air leak determination means for determining the presence or tendency of air leak in which air leaks into the chest cavity based on the minimum negative pressure value calculated by the negative pressure calculation means or the minimum negative pressure related value related to the minimum negative pressure value; ,
Output control means for causing the output means to output information relating to the determination result of the air leak determination means,
An air leak monitoring device. The calculation means further includes data processing means for calculating a difference between the minimum negative pressure value as the minimum negative pressure related value and a set negative pressure value preset as a pressure in the suction circuit,
The air leak monitoring device according to claim 9, wherein the air leak determination unit determines the presence or absence of the air leak based on whether or not the state where the difference calculated by the data processing unit is equal to or less than a threshold continues for a determination time or more. . The calculation means further includes data processing means for calculating a fluctuation range per predetermined time of the minimum negative pressure value as the minimum negative pressure related value,
10. The air leak monitoring according to claim 9, wherein the air leak determination unit determines the presence or absence of the air leak based on whether or not the state where the fluctuation range calculated by the data processing unit is equal to or less than a threshold continues for a determination time or more. apparatus. The suction circuit is incorporated in a thoracic drain system that sucks the gas in the thoracic cavity through a water-sealed chamber containing a liquid by using a negative pressure generated by a suction source;
The pressure measuring means measures a pressure between the suction source and the water seal chamber,
Further comprising bubble generation state acquisition means for acquiring a bubble generation state in the water seal chamber;
The air leak monitoring device according to any one of claims 9 to 11, wherein the air leak determination unit determines the presence or absence of the air leak based on the bubble generation state acquired by the bubble generation state acquisition unit.   If the determination result based on the minimum negative pressure value or the minimum negative pressure related value related to the presence or absence of the air leak is different from the determination result based on the bubble generation state, the output control means determines the determination result that there is an air leak. The air leak monitoring apparatus according to claim 12, wherein the output unit outputs the information related to the determination result. The calculation means further includes data processing means for calculating a difference between the minimum negative pressure value as the minimum negative pressure related value and a set negative pressure value preset as a pressure in the suction circuit,
The air leak monitoring apparatus according to claim 9, wherein the air leak determination unit determines whether or not the air leak tends to decrease based on a temporal change of the difference calculated by the data processing unit. The negative pressure calculating means calculates a maximum value of negative pressure or a value in the vicinity thereof as a maximum negative pressure value based on the pressure every predetermined time measured by the pressure measuring means,
The output control means has stage dividing means for dividing the maximum negative pressure value calculated by the negative pressure calculation means or the maximum negative pressure related value related to the maximum negative pressure value into a plurality of stages with respect to the magnitude, and Each step of the maximum negative pressure value or each step of the maximum negative pressure related value, and each step of the maximum negative pressure value or each step of the maximum negative pressure related value divided into a plurality of steps by the step dividing means The air leak monitoring device according to any one of claims 9 to 13, wherein the output unit outputs information associated with a determination result of the air leak determination unit as information on the determination result.   The air leak monitoring apparatus according to claim 15, wherein the maximum negative pressure related value is a difference between the maximum negative pressure value and the minimum negative pressure value.   The air leak monitoring device according to claim 15, wherein the maximum negative pressure related value is a difference between the maximum negative pressure value and a set negative pressure value preset as a pressure in the suction circuit.

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