JP2016209461A - Pneumoperitoneum system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pneumoperitoneum system capable of highly accurately determining an occluded state.SOLUTION: The pneumoperitoneum system: calculates a pressure gradient Ra of a measurement duct, with an air supply ON (S3); when a flow integrated value Qsum of gas supplied with an output of an electropneumatic proportional valve regulated, reaches a threshold Qh, turns off the air supply, and calculates a pressure gradient Rb of the measurement duct (S10); and measures a lapse time Tb after turning off the air supply (S11). When Tb≥Th2 or Rb≥Rh, the pneumoperitoneum system compares the lapse time Tb with a first determination threshold Th1 and a second determination threshold Th2, to determine an occluded state of the measurement duct (S14) and transfers to processing according to the determination result of the occluded state.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a pneumoperitoneum system that feeds gas to inhale.

  In recent years, surgical operations under observation with a laparoscope have been widely adopted. In a surgical operation using a laparoscope, a predetermined gas such as carbon dioxide gas is supplied into the abdominal cavity, and an insufflation apparatus or an insufflation system is used to secure an observation field by the laparoscope and an area for operation. It is done.

  In such a pneumoperitoneum or pneumoperitoneum system, if a closed state such as clogging occurs in a duct communicating with the abdominal cavity, the pressure in the abdominal cavity may not be accurately detected.

  For this reason, Patent Document 1 detects the magnitude of the pressure change in the gas supply line when the gas for insufflation is flowed into or out of the gas supply line to which the pneumoperitoneal tube is connected. A technique for determining a clogged state of an insufflation tube based on the pressure change detection data is disclosed.

  Patent Document 2 discloses the pressure of the first cycle of pressure oscillation in the pipe line immediately after the gas is discharged from the gas discharge port of the gas supply pipe line to which the insufflation tube is connected and the gas discharge port is closed. A technique for determining whether the abdominal pressure is in a normal state, a tube clogged, or an abdominal overpressure state from the pressure detection result at the time of ascent is disclosed.

JP-A-6-209901 Japanese Patent Laid-Open No. 9-38029

  Patent Documents 1 and 2 detect the presence or absence of clogging, but do not disclose determining the degree of clogging in more detail. In practice, clogging (or occlusion) may be a slight occlusion state or a severe occlusion state, and different air supply control is required for the former determination result and the latter determination result. In order to determine such a closed state, the techniques of Patent Documents 1 and 2 lack a function for determining. Therefore, a pneumoperitoneum system that can determine the occlusion state with higher accuracy and has higher reliability is desired.

  This invention is made | formed in view of the said situation, and it aims at providing the pneumoperitoneum system which can determine an obstruction | occlusion state accurately.

  An insufflation system according to one aspect of the present invention includes an insufflation apparatus having a control unit that controls air supply of a predetermined gas into the abdominal cavity, and a first trocar inserted into the abdominal cavity after being inserted into the abdominal wall. Connected to a gas supply line for supplying the gas from the pneumoperitoneum into the abdominal cavity and a second trocar inserted into the abdominal wall and inserted into the abdominal cavity. A measuring line for measuring the internal pressure, an air supply switching unit provided on the air supply line, for switching the intermittent state of the air supply from the air supply line to the abdominal cavity, and provided on the measurement line A line pressure measuring unit for measuring the line pressure of the measurement line, and at the time of air supply control of the gas, after switching the intermittent state of the air supply of the air supply line by the air supply switching unit, The time until a predetermined change occurs in the rate of change of the line pressure measured by the line pressure measurement unit. A change time measurement unit that measures as a conversion time, and a change time measured by the change time measurement unit and a predetermined determination value, and a blockage state determination unit that determines a blockage state of the measurement pipeline, Have.

  According to the present invention, it is possible to accurately determine the closed state.

Configuration diagram of pneumoperitoneum system Explanatory drawing showing the measurement line for abdominal pressure Explanatory drawing which shows the change of the measurement pressure in the state without the blockade after air supply OFF from air supply ON Explanatory drawing which shows the change of the measurement pressure in the state with the obstruction after air supply OFF from air supply ON Explanatory drawing which shows the delay of the change of the measurement pressure after air supply ON after air supply ON Explanatory drawing which shows the change of the measurement pressure in the state without the obstruction | occlusion after air supply ON from air supply OFF Explanatory drawing which shows the change of the measurement pressure in the state with the obstruction after air supply ON after air supply OFF Explanatory drawing which shows the delay of the change of the measurement pressure after air supply ON from air supply OFF Flow chart of air supply control program Explanatory drawing showing changes in measured pressure

Embodiments of the present invention will be described below with reference to the drawings.
An insufflation system 1 shown in FIG. 1 includes an insufflation apparatus 3 for supplying carbon dioxide gas as a predetermined gas into the abdominal cavity 2a of a patient 2 placed on an operating table B, and inhaling the abdominal cavity 2a. The endoscope apparatus 4 for observing the inside of the abdominal cavity 2a of the patient 2 and the treatment tool 6 for performing treatment for treatment under the observation of the endoscope 5 constituting the endoscope apparatus 4 are provided.

  The endoscope apparatus 4 includes an endoscope 5 inserted into the abdominal cavity 2 a via the first trocar 13, and a light source apparatus 7 that supplies illumination light for optical observation to the endoscope 5. And a video processor 8 as a signal processing device that drives an image sensor provided in the endoscope 5 and performs signal processing on an image signal captured by the image sensor, and an image signal generated by the video processor 8 is input. By doing so, it has a monitor 9 as a display device that displays an image in the observation visual field within the abdominal cavity imaged by the imaging device as an endoscopic image.

  The pneumoperitoneum system 1 has a carbon dioxide gas cylinder (hereinafter simply referred to as a gas cylinder) 10 connected to an air supply base 11 a provided in the housing 3 a of the pneumoperitoneum 3. The gas cylinder 10 serves as a gas supply source for supplying carbon dioxide gas to the insufflation apparatus 3, and is connected to one end of the internal pipe line 11 in the insufflation apparatus 3 through an air supply base 11a.

  The internal conduit 11 includes a decompressor 21 that performs decompression, an electropneumatic proportional valve 22 that adjusts and outputs the pressure of carbon dioxide gas by an electric signal, an electromagnetic valve 23 that opens and closes by a control signal, and a flow sensor that measures an air supply flow rate. 24, the first pressure sensor 25 for measuring the pressure in the internal conduit 11 is sequentially arranged from the air supply base 11a on the upstream side to the air supply base 11b on the downstream side.

  One end of a flexible air supply tube 12 that forms an external conduit connected to the insufflation apparatus 3 is connected to the air supply base 11 b on the downstream side of the internal conduit 11. The other end of the insufflation tube 12 is connected to a first trocar 13 that forms an insufflation trocar (or an insufflation trocar) inserted into the abdominal wall of the patient 2.

  In the first trocar 13, the insertion portion 5 a of the endoscope 5 is inserted into a hollow guide tube, and the carbon dioxide gas fed from the air feeding tube 12 through the hollow path is connected to the air feeding tube 12. Air is fed into the abdominal cavity from the connecting portion using the gap between the insertion portion 5a and the guide tube in the first trocar 13 as a passage.

  Thus, the abdominal cavity 2a communicates with the internal conduit 11 of the insufflation apparatus 3 connected to the gas cylinder 10, the air supply tube 12, the air supply tube 12 and the first trocar 13 connected to the internal conduit 11. By the passage, an air supply conduit 14 for supplying the carbon dioxide gas supplied from the gas cylinder 10 into the abdominal cavity 2a is formed.

  In addition, as described below, the pneumoperitoneum system 1 according to the present embodiment is used as a conduit system for measuring an intraperitoneal pressure (also simply referred to as an intraabdominal pressure or an abdominal pressure) as an intraabdominal pressure. It has a measurement line 19 of a different system from the tracheal line 14.

  A second trocar 15 forming a measurement trocar is inserted into the abdominal wall of the patient 2, and one end of the measurement tube 17 is connected to a connection portion of the second trocar 15. The measurement tube 17 is a flexible tube having an inner diameter of about 2 mm and a length of about 3 m, for example.

  The other end of the measuring tube 17 is connected to a pipe line 16 in the insufflation apparatus 3 via a measuring cap 16a, and a pipe pressure measuring unit for measuring the pipe pressure of the measuring pipe line 19 is connected to the pipe line 16. Is connected to the second pressure sensor 35. In the following description, the “second pressure sensor 35” is appropriately described as “pressure sensor 35”.

  A filter 18 (see FIG. 2) for preventing the inside of the pneumoperitoneum 3 from being contaminated is inserted in the measurement base 16a. This filter 18 is replaced with a new and clean one at each operation.

  As shown in FIG. 2, the outer tube of the treatment instrument 6 is inserted into the guide tube of the second trocar 15. In the second trocar 15, the distal end opening of the second trocar 15 inserted into the abdominal cavity is connected to the connection portion using a gap between the outside of the outer tube of the treatment instrument 6 and the inside of the guide tube as a passage. The measurement tube 17 communicates with an open end serving as one end of the measurement tube 17.

  As shown in FIG. 2, when the outer tube of the treatment instrument 6 is inserted into the second trocar 15, a passage inside the second trocar 15 is provided by a rubber lid 15a provided with a cross notch for insertion. Is cut off from the outside.

  In this way, the measurement tube 17 connected to the second trocar 15, the passage communicating with the abdominal cavity 2 a via the measurement tube 17 and the second trocar 15, and further in the pneumoperitoneum apparatus 3 to which the measurement tube 17 is connected. A measurement line 19 for measuring the pressure in the abdominal cavity 2a is formed by the line 16.

  The pipe line 16 in the pneumoperitoneum 3 is a conduit for guiding pressure to the second pressure sensor 35, and the second pressure sensor 35 is connected to the measurement tube 17 via the measurement cap 16a. The pipe line 16 can be omitted.

  The insufflation apparatus 3 includes a controller 100 having a control unit 101 that controls an insufflation operation or the like of the insufflation apparatus 3 and a target target abdominal pressure (or insufflation) by the insufflation (insufflation) from the insufflation apparatus 3. A panel 27 for setting (or inputting) a setting pressure) and a display 28 for displaying the measured abdominal pressure, the air flow rate, and the like are provided. The controller 100 is mainly configured by a microcomputer having a central processing unit (CPU), but can be configured by using an electronic circuit including a timer circuit, a comparison circuit, an arithmetic circuit, a memory circuit, and the like. It is.

  In addition, a user such as a surgeon performs an instruction operation (or instruction input) for starting an insufflation (feeding) operation or ending an insufflation operation on the controller 100 on the controller 100. A panel 27 is connected.

  The gas cylinder 10 supplies a high-pressure carbon dioxide gas of, for example, about 6 MPa to the decompressor 21 in the insufflation apparatus 3 through the air supply base 11a. The pressure reducer 21 reduces the pressure to a low pressure of about 0.4 Mpa, for example, and sends it to the electropneumatic proportional valve 22. The electro-pneumatic proportional valve 22 is a valve that variably controls the air supply pressure that is adjusted to a pressure according to the control signal and supplied to the electromagnetic valve 23 side when a control signal is applied from the control unit 101 of the controller 100. It is.

  In the air supply control by the controller 100, the control unit 101 is electro-pneumatic proportional to the control signal corresponding to the difference between the actually measured abdominal pressure and the target abdominal pressure (or set pressure) set by the panel 27. Applied to valve 22. The electropneumatic proportional valve 22 supplies carbon dioxide gas having a predetermined pressure (for example, about 0 to 80 mmHg) corresponding to the difference to the electromagnetic valve 23 side.

  Specifically, when the difference in the abdominal pressure actually measured compared to the set pressure is large as when the air supply is started, the electropneumatic proportional valve 22 supplies air with a large pressure, Since the difference decreases as the pressure approaches the set pressure, the electropneumatic proportional valve 22 enters a state in which air is supplied at a pressure close to zero.

  The electromagnetic valve 23 forms an air supply switching unit that switches an intermittent state of the supply of carbon dioxide gas from the air supply line 14 into the abdominal cavity 2a, and is electrically controlled by an ON / OFF control signal from the control unit 101. Then, the valve opens and closes to open and close the air supply conduit 14 to switch between the intermittent state of air supply execution (air supply ON) and air supply stop (air supply OFF). The electromagnetic valve 23 is opened by a control signal for initiating an insufflation (feeding) and closed by a control signal for ending insufflation.

  The flow sensor 24 sends the measured air supply flow rate to the control unit 101. The control unit 101 samples the air supply flow rate measured at an appropriate period (for example, about 10 msec), integrates it, and calculates the integrated flow rate Q. The carbon dioxide gas that has passed through the flow rate sensor 24 is supplied into the abdominal cavity through the air supply tube 12 and the first trocar 13. The first pressure sensor 25 measures the pressure in the internal conduit 11 and outputs it to the control unit 101.

  The control unit 101 adjusts the air pressure (in other words, adjusts the air flow rate) based on the abdominal pressure of the abdominal cavity 2a, and controls the air feeding operation from the air feeding line 14. In a normal state, the abdominal pressure is equivalent to the line pressure (measurement pressure) of the measurement line 19 measured by the pressure sensor 35, but the measurement tube 17 forming the main part of the measurement line 19 is flexible. Therefore, the measurement accuracy of the abdominal pressure may be deteriorated because it is bent during use and the inner diameter becomes flat, resulting in a slight semi-occlusion where the original duct characteristics cannot be obtained. .

  In addition, the filter 18 disposed in the middle of the measurement pipe line 19 is clogged with fine particles or the like and becomes blocked, or the narrow passage in the second trocar 15 becomes clogged due to the entry of foreign matter. There is also a risk of being in a closed state. In addition, closing the cock (not shown) of the second trocar 15 as an erroneous operation may result in a closed state.

  As a typical example of such a closed state, FIG. 2 schematically shows a closed portion 36 that generates a closed state when the inner diameter is substantially reduced in the middle of the measurement tube 17. In many cases, the occlusion portion 36 is generated in the long measuring tube 17 having flexibility.

  For this reason, the controller 100 has a function for determining the closed state of the measurement conduit 19 in addition to the function of controlling the air supply into the abdominal cavity by the control unit 101. The controller 100 determines the closed state of the measurement pipeline 19 based on the change in the pipeline pressure of the measurement pipeline 19 when the air supply is switched between ON and OFF.

  Here, a determination algorithm of the controller 100 that determines the closed state of the measurement pipe line 19 will be described. The following description will be divided into (A) when air supply is turned from ON to OFF and (B) when air supply is turned from OFF to ON, but basically the same algorithm.

(A) When the air supply is switched from ON to OFF In the state where the measurement line 19 is not blocked, the abdominal pressure Pc and the line pressure (measured pressure measured by the pressure sensor 35) Pm of the measurement line 19 are As shown in FIG. 3, it changes with time. That is, since gas is sent into the abdominal cavity when the air supply is on, the abdominal pressure Pc increases as shown in FIG. 3, and when the air supply is turned off, the increase in the abdominal pressure Pc stops. In other words, the rate of change of the abdominal pressure Pc (the amount of change in pressure per unit time) changes at the time tc when the air supply is switched from ON to OFF. At this time, since the measurement line 19 is not blocked, the measurement pressure Pm behaves similarly to the abdominal pressure Pc, and the rate of change of the measurement pressure Pm changes when the air supply is turned off from on.

  On the other hand, in the state where the measurement line 19 is blocked, the abdominal pressure Pc and the measurement pressure Pm when the air supply is switched from ON to OFF change as shown in FIG. The blockage of the measurement pipe line 19 means that the flow path resistance of the measurement pipe line 19 is higher than the original design value. Therefore, when the air supply is ON, the abdominal pressure Pc shown in FIG. 4 behaves the same as in FIG. 3, but the measured pressure Pm becomes lower than the abdominal pressure Pc, and the measured pressure increases as the abdominal pressure Pc increases. Pm also rises.

  When the air supply is switched from ON to OFF, the increase in the measurement pressure Pm does not stop immediately, but the increase stops after the elapse of time τ. Such a phenomenon occurs because, when the measurement line 19 is blocked, a delay occurs until the pressure change in the abdominal cavity is transmitted to the pressure sensor 35 (delay time τ).

  The manner in which this delay occurs varies depending on the degree of blockage of the measurement pipe 19. After the air supply is turned off from on, in the state where there is no blockage in the pipeline, there is almost no delay in the measured pressure Pm as shown by the line L1 in FIG. As the degree of blockage of the pipeline increases, delay times τ1, τ2 (τ1 <τ2) are generated as indicated by the line L2 → L3. When the measurement tube 17 forming the measurement line 19 is bent or the like, and the line is completely blocked, as shown by the line L4, the measurement pressure changes when the air supply is turned on and off. Absent. This can be considered as an infinite time delay (τ → ∞).

  Therefore, after changing the air supply from ON to OFF, the rate of change of the pipe pressure of the measurement pipe 19 with time is obtained, and the delay time until the predetermined change occurs in the pipe pressure change rate is measured. By doing so, the blockage state of the measurement pipe line 19 can be determined by the magnitude of the delay time. The delay time until a predetermined change occurs in the rate of change in the pipeline pressure is grasped as the change time until the rate of change in the pipeline pressure reaches the set value (elapsed time after the air supply is turned from ON to OFF). be able to.

  The set value for the rate of change of the line pressure is set based on the rate of change of the line pressure of the measurement line 19 in the air supply ON state before turning off the air supply, and before the air supply is turned off. For the change rate, for example, a predetermined change rate set in consideration of the configuration of the pipeline system, the air supply pressure, the environmental conditions, and the like is used. The set value can be a fixed value determined in advance under limited conditions.

(B) When the air supply is changed from OFF to ON The case where the air supply is changed from OFF to ON is the same as the case where the air supply is changed from ON to OFF. As shown in FIG. 6, at the time to when the air supply is turned from OFF to ON, the change rate of the measurement pressure Pm changes like the abdominal pressure Pc, and the measurement pressure Pm immediately increases. On the other hand, in the state where the measurement line 19 is blocked, as shown in FIG. 7, when the air supply is turned from OFF to ON, the abdominal pressure Pc immediately rises, whereas the measurement pressure Pm does not rise immediately. A delay time τ ′ occurs before a change appears in the change rate of the measurement pressure Pm.

  Even in this case, the manner in which the delay occurs differs depending on the degree of blockage of the pipeline. In a state where there is no blockage in the pipeline, as shown by the line L1 'in FIG. 8, the measured pressure Pm immediately rises when the air supply is turned on from OFF, and there is almost no delay. As the degree of occlusion increases, delay times τ1 ′ and τ2 ′ (τ1 ′ <τ2 ′) are generated as indicated by the line L2 ′ → L3 ′. When the measurement tube 17 is bent or the like, and the pipe line is completely blocked, as shown by the line L4 ', the measurement pressure Pm does not change even if air is supplied. This can be considered as an infinite time delay (τ ′ → ∞).

  Therefore, after changing the air supply from ON to OFF, the rate of change of the pipe pressure of the measurement pipe 19 with time is obtained, and the delay time until the predetermined change occurs in the pipe pressure change rate is measured. As a result, as in the case where the air supply is turned from ON to OFF, the closed state of the measurement pipe line 19 can be determined based on the delay time.

  Based on the above, the controller 100 includes a change time measuring unit 102 and a closed state determining unit 103 as functional units for determining the closed state of the measurement pipeline 19 as shown in FIG. These functional units are realized as a part of the function of the controller 100 in the present embodiment, but may be configured as an apparatus independent of the controller 100 and exchange information with each other via a communication line or the like. .

  The change time measuring unit 102 switches the electromagnetic valve 23 of the air supply line 14 from open to closed and turns the air supply from ON to OFF, or switches the electromagnetic valve 23 from closed to open to change the air supply from OFF to ON. After that, the pipe pressure of the measurement pipe 19 is monitored, and the change time until a predetermined change occurs in the change rate of the pipe pressure is measured.

  Specifically, the change time is measured as an elapsed time until the rate of change in the pipe pressure of the measurement pipe 19 reaches a set value, and the delay state of the pressure behavior due to the blockage of the pipe is determined by this elapsed time. Check out. The set value of the change rate is set based on the change rate of the pipe pressure of the measurement pipe line 19 before the air supply is switched from ON to OFF or from OFF to ON. For example, assuming that 30% of the change rate of the pipeline pressure immediately before switching the solenoid valve 23 from open to closed or from closed to open is the set value Rh, the change rate of the pipeline pressure after switching is 30% of the change rate before switching. Measure the elapsed time until.

  However, as described above, depending on the closed state of the pipeline, it may take an infinite or nearly infinite time for the rate of change of the pipeline pressure to reach the set value. Provided, when a time equal to or greater than a second determination threshold value Th2 described later indicating that the measurement line 19 is in a severely closed state has elapsed before the rate of change in the line pressure reaches the set value Rh, Considering the time as the time when the set value Rh has been reached, the timing is stopped, and it is avoided that the time until the determination increases.

  The blockage state determination unit 103 determines the blockage state of the measurement pipeline 19 by comparing the elapsed time measured by the change time measurement unit 102 with a preset determination value. In the present embodiment, the closed state of the measurement pipeline 19 is determined in three stages: a normal state that is not blocked, a lightly blocked state that is in a slightly blocked state, and a severely blocked state that is in a severely closed state. To do. For this reason, as a determination value for determining the occlusion state, the first determination threshold Th1 serving as a boundary between the normal state and the slight occlusion state, and the boundary between the slight occlusion state and the severe occlusion state are used. A second determination threshold value Th2 larger than Th1 is set in advance.

  Specifically, the occlusion state determination unit 103 determines the normal state when the elapsed time measured by the change time measurement unit 102 is equal to or less than the first determination threshold Th1, and exceeds the first determination threshold Th1. When it is less than the second determination threshold Th2, it is determined that the state is slightly occluded. When the elapsed time measured by the change time measuring unit 102 is equal to or greater than the second determination threshold Th2, it is determined that the state is a severe blockage. Here, in the slight occlusion state, the pressure in the abdominal cavity can be measured, but in the severe occlusion state, the pressure in the abdominal cavity may be erroneously measured.

  Next, program processing for air supply control including determination of the closed state of the measurement pipeline 19 in the controller 100 will be described with reference to the flowchart of FIG.

  In FIG. 9, a process for determining the blockage state of the measurement pipe 19 by switching the air supply from ON to OFF will be described. Therefore, the occlusion state can be determined by a similar algorithm.

  The program processing shown in FIG. 9 is started by an operation input for insufflation start from the panel 27 and is ended by an operation input for insufflation end. In the normal state where the measurement line 19 is not obstructed, when the abdominal pressure reaches the set pressure, air is supplied at the set flow rate, and after the start of the air supply, the integrated value of the air supply flow rate reaches the threshold value. The air supply is temporarily stopped to determine the closed state of the measurement pipeline 19. If it is determined that the measurement pipe line 19 is blocked, the normal air supply control is changed to switch to the air supply control corresponding to the closed state of the measurement pipe line 19.

  Specifically, when the air supply control program of FIG. 9 is started, first, in the first step S1, the electromagnetic valve 23 of the air supply line 14 is opened, and the carbon dioxide gas of the gas cylinder 10 is supplied from the air supply tube 12 to the first. The air is fed into the abdominal cavity 2a through one trocar 13 (air feeding ON). In step S2, the pressure sensor 35 measures the line pressure of the measurement line 19 corresponding to the abdominal pressure.

  Next, the process proceeds to step S3, and the pressure gradient Ra is calculated from the measurement result of the pressure sensor 35. The pressure gradient Ra here is the pressure change rate on the time axis, and the measured time change amount of the pipe pressure corresponds to the pressure gradient Ra.

As shown in FIG. 10, the measurement of the pipe pressure by the pressure sensor 35 is performed every predetermined time Tm (for example, Tm = 10 msec), and the pressure gradient Ra is obtained from the comparison with the previous measurement value every time it is measured. For example, if the current measured pressure is Pm (i) and the previous measured pressure is Pm (i-1), the pressure gradient Ra is given by the following equation (1).
Ra = (Pm (i) -Pm (i-1)) / Tm (1)

  Then, it progresses to step S4, a control signal is applied to the electropneumatic proportional valve 22 based on the measurement result of step S2, and the output (valve opening / closing amount) of the electropneumatic proportional valve 22 is set (or controlled). Immediately after the start of insufflation, the measured abdominal pressure is considerably lower than the set pressure. Therefore, the output of the electropneumatic proportional valve 22 is controlled to be a large value, and the measured abdominal pressure is set to the set pressure. Control is performed so as to decrease the output of the electropneumatic proportional valve 22 as it approaches. By controlling so that the output of the electropneumatic proportional valve 22 decreases as the set pressure approaches, it is possible to prevent the abdominal pressure from greatly exceeding the set pressure.

  In the next step S5, the air flow rate is measured by the flow sensor 24, and the flow rate integrated value Qsum is calculated from the measurement result of the air flow rate in step S6. The integration of the air supply flow rate is a process for examining how much gas has been supplied in total since the start of air supply in step S1, and the flow rate integrated value Qsum reaches a predetermined threshold value Qh in step S7. Find out if you did.

  If the flow rate integrated value Qsum does not reach the threshold value Qh (Qsum <Qh), the air supply is continued and the process returns from step S7 to step S2. On the other hand, when the flow rate integrated value Qsum has reached the threshold value Qh (Qsum ≧ Qh), the process proceeds from step S7 to step S8 and subsequent steps.

  In step S8, the solenoid valve 23 is closed to stop air supply (air supply OFF), and in step S9, the pressure sensor 35 measures the line pressure of the measurement line 19 after the air supply is turned off. In step S10, the pressure gradient Rb after the air supply is turned off is calculated from the measurement result of the pressure sensor 35. The pressure gradient Rb is calculated in the same manner as the pressure gradient Ra in step S3 (see equation (1)), and is given by the amount of change in the pipeline pressure per time Tm.

  Thereafter, the process proceeds to step S11, where the elapsed time Tb after the air supply is turned off (the electromagnetic valve 23 is closed) is measured. In step S12, the elapsed time Tb reaches the second determination threshold Th2 for determining the severely closed state. Check whether or not. When Tb <Th2, the process proceeds from step S12 to step S13, and when Tb ≧ Th2, the process proceeds from step S12 to step S14.

  Since Tb <Th2 initially after the air supply OFF, the process proceeds from step S12 to step S13, and it is checked whether or not the pressure gradient Rb has reached the set value Rh. In step S13, when Rb <Rh, the process returns to step S9. When Rb ≧ Rh, the elapsed time at that time is recorded and the process proceeds to step S14, and the closed state of the measurement pipeline 19 is determined.

  In this case, when the air supply is OFF, a response delay of a predetermined time Td occurs after the control signal is sent to the electromagnetic valve 23 until the valve actually starts to close (usually, Td = 20 msec). During this response delay, as shown in FIG. 10, the pressure gradient Rb hardly changes, and after the delay time Td, the pressure gradient Rb gradually starts to change.

  In step S13, the elapsed time Tb until the pressure gradient Rb reaches the set value Rh from the pressure gradient Ra immediately before closing the solenoid valve 23 is recorded. In step S14, the measurement pipe 19 is closed from the elapsed time Tb. Determine. As described above, the set value Rh is, for example, 30% of the pressure gradient Ra immediately before the air supply is turned off.

  However, if the time during which the pressure gradient Rb is less than the set value Rh is equal to or greater than the second determination threshold Th2, the time at that time is regarded as the elapsed time Tb when the pressure gradient Rb has reached the set value Rh. The process proceeds from step S12 to step S14.

  The blockage state determination in step S14 is performed by comparing the elapsed time Tb in step S12 or step S13 with the first determination threshold value Th1 and the second determination threshold value Th2, for example, as shown below. Values F1, F2, and F3 corresponding to the result are set in the determination flag FL. The first determination threshold Th1 is, for example, Th1 = Td + 20 msec when considering the response delay of closing of the electromagnetic valve 23, and the second determination threshold Th2 is, for example, Th2 = Td + 150 msec.

Judgment flag Judgment result Elapsed time FL = F1 Normal state not closed Tb ≦ Th1
FL = F2 Minor obstruction that does not hinder measurement of abdominal pressure Th1 <Tb <Th2
FL = F3 Severe obstruction in which the abdominal pressure cannot be measured accurately Tb ≧ Th2

  Thereafter, the process proceeds to step S15 where the determination result of the closed state is identified by referring to the determination flag FL, and the process proceeds to a process corresponding to the closed state. For example, in the case of FL = F1, since it is a normal state that is not closed, the process returns from step S15 to step S1 to resume air supply. Further, when FL = F2, since there is no problem in the measurement of the abdominal pressure in a slight occlusion state, the process proceeds from step S15 to step S16, and the threshold value Qh for the flow rate integrated value Qsum is reset to a smaller value, Return to step S1.

  That is, in the present embodiment, since the determination operation of the closed state is performed every time a predetermined amount of air is supplied, the determination operation is frequently performed by reducing the threshold Qh of the integrated flow rate that determines the timing for turning off the air supply. To be done. In a slight blockage state, it is assumed that the blockage is gradually progressing due to foreign matters entering the measurement pipe line 19 or the like. Therefore, when a slight occlusion state is detected, by adjusting the frequency of the determination operation, adjustment is made so that it can be quickly detected even if it falls into a severe occlusion state.

  On the other hand, if it is determined in step S15 that FL = F3 and the state is severely closed, the process proceeds from step S15 to step S17, and the air supply control is switched to the intermittent air supply method. In the intermittent air supply method, gas supply and detection of abdominal pressure by the first pressure sensor 25 of the air supply line 14 are alternately performed via the air supply line 14 without using the measurement line 19. Thus, this is an air supply system in which gas is intermittently sent so that the abdominal pressure becomes a predetermined value. In this intermittent air supply method, the air supply efficiency is worse than that in the method using the measurement pipeline 19, but the procedure can be continued without any problem.

  As described above, in the present embodiment, after switching the intermittent state of the air supply, the line pressure of the measurement line 19 communicating with the abdominal cavity 2a is monitored by the pressure sensor 35, and the blocked state is determined from the rate of change of the line pressure. Therefore, the degree of blockage or the blockage state as the degree of clogging of the measurement pipe line 19 can be accurately determined from the normal pressure measurement result without requiring a special device for the determination of the blockage state.

  Moreover, in the present embodiment, the measurement pipe line 19 communicating with the abdominal cavity 2a is a pipe line whose end is closed, and the closed state is determined based on a change in pressure in the pipe line whose end is closed. Compared with a measurement method in which carbon dioxide used for insufflation (or air supply) is released to the atmosphere, replenishment of carbon dioxide can be suppressed to a minimum, and the economy is excellent.

  In addition, according to the present embodiment, the pneumothorax operation can be further continued in accordance with the determined occlusion state, so that the surgeon performs an operation with the treatment tool 6 under observation with an endoscope. Can be performed smoothly.

  Specifically, when it is determined that the occlusion state is a slight occlusion state, the operator maintains the abdominal pressure substantially equal to the set pressure by performing air supply control in the same manner as in the non-occlusion state. Surgery with the treatment tool 6 under observation with an endoscope can be performed smoothly. On the other hand, when it is determined that the occlusion state is a severe occlusion state in which the pressure in the measurement pipe line 19 cannot be measured, by performing intermittent air supply on the side of the air supply pipe line 14, the operator can observe under the endoscope. It is also possible to ensure the function of performing an operation with the treatment tool 6 in the above.

DESCRIPTION OF SYMBOLS 1 Insufflation system 2 Patient 2a Abdominal cavity 3 Insufflation apparatus 4 Endoscope apparatus 5 Endoscope 6 Treatment tool 7 Light source apparatus 8 Video processor 9 Monitor 10 (Carbon dioxide) gas cylinder 11 Internal pipe line 12 Air supply tube 13 1st trocar DESCRIPTION OF SYMBOLS 14 Air supply line 15 2nd trocar 16 Pipe 17 Measurement tube 19 Measurement line 21 Pressure reducer 22 Electropneumatic proportional valve 23 Electromagnetic valve 24 Flow rate sensor 25 1st pressure sensor 27 Panel 35 2nd pressure sensor 36 Blocking part DESCRIPTION OF SYMBOLS 100 Controller 101 Control part 102 Change time measurement part 103 Occlusion state determination part Pc Abdominal pressure Pm Measurement pressure Ra Pressure gradient (Pressure change rate of air supply ON)
Rb pressure gradient (pressure change rate after air supply OFF)
Tb elapsed time (change time)
Rh (change rate) set value Th1 First judgment threshold Th2 Second judgment threshold

Claims (4)

An insufflation apparatus having a control unit for controlling the insufflation of a predetermined gas into the abdominal cavity;
An insufflation line connected to a first trocar inserted into the abdominal cavity and inserted into the abdominal wall, for supplying the gas from the insufflation apparatus into the abdominal cavity;
A measuring line for measuring pressure in the abdominal cavity, connected to a second trocar inserted into the abdominal wall and inserted into the abdominal cavity;
An air supply switching unit that is provided on the air supply line and switches an intermittent state of air supply from the air supply line to the abdominal cavity;
A pipe pressure measurement unit that is provided on the measurement pipe and measures the pipe pressure of the measurement pipe;
During the gas supply control, a predetermined change occurs in the rate of change of the line pressure measured by the line pressure measuring unit after switching the intermittent state of the air supply of the air supply line by the air supply switching unit. A change time measurement unit that measures the time until the change time,
A blockage state determination unit that compares a change time measured by the change time measurement unit with a predetermined determination value and determines a blockage state of the measurement pipeline;
A pneumoperitoneum system characterized by comprising:   The pneumoperitoneum system according to claim 1, wherein the change time in the change time measuring unit is an elapsed time until the rate of change of the pipe pressure of the measurement pipe reaches a set value.   The set value in the change time measuring unit is set based on a rate of change in the line pressure of the measurement line before switching the air supply intermittent state of the air supply line. The described pneumoperitoneum system. The determination value in the blockage state determination unit includes a first determination threshold value that is set in advance according to the blockage state of the measurement pipeline, and a second determination threshold value that is greater than the first determination threshold value,
The blocking state determination unit
When the change time is equal to or less than the first determination threshold, it is determined that the measurement pipeline is in a normal state that is not blocked;
When the change time exceeds the first determination threshold and is less than the second determination threshold, the measurement conduit is in a slight occlusion state but is in a slight occlusion state in which the pressure in the abdominal cavity can be measured. Judgment,
When the change time is equal to or greater than the second determination threshold value, it is determined that the measurement pipeline is in a severe occlusion state and is in a severe occlusion state that may erroneously measure the pressure in the abdominal cavity. The pneumoperitoneum system according to claim 1.

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