EP1624789A1

EP1624789A1 - Method and device for recording operating incidents of medical instruments

Info

Publication number: EP1624789A1
Application number: EP04742444A
Authority: EP
Inventors: Jean-François Ognier
Original assignee: Sopro SA
Current assignee: Sopro SA
Priority date: 2003-04-16
Filing date: 2004-04-06
Publication date: 2006-02-15
Also published as: US20070073493A1; FR2853980A1; WO2004093665A1; CN1816302A; JP2006523483A; FR2853980B1

Abstract

The aim of the inventive method is to continuously measure, monitor and record operating parameters of medical appliances especially a medical insufflator, by storing the parameters measured on a pre-determined number of last operating cycles of the appliance, or over a pre-determined sliding operating period of said appliance. If an operating incident is detected, the data recorded at the time of the incident is stored. Furthermore, during the setting-up of the medical instrument, possible malfunctions of essential components are detected and the detected defects of said components are recorded.

Description

Method and device for recording operating incidents of medical devices

The present invention relates to a method, and a device for implementing this method, for recording operating incidents of medical devices.

The malfunctions of medical devices, which may cause danger for patients or users of these devices, are reported in France to the French Agency for Health Safety of Health Products (AFSSAPS), in the framework of a so-called materiovigilance procedure. This body may prohibit the use or marketing of the device subject to incidents, and inform the other Member States of the European Community, under Directive 93/42.

All medical devices and devices that may have a direct or indirect effect on the health of patients, such as: infusion pumps, surgical pumps, extra-corporeal circulation pumps, medical or surgical insufflators, respiratory assistance fans, etc. A more particular example is the medical insufflator with automatic regulation of gas flow, intended for diagnostic and surgical endoscopy, described in the published French patent application No. 2,716,627 of the same inventor, or its equivalents such as European Patent No. 0 699 083 and US Patent No. 5,800,381.

Unfortunately, the conditions under which operating incidents occur are very often poorly described or even poorly identified, and practitioners frequently tend to invoke the failure of a medical device to exonerate themselves from their own responsibilities.

As a result, in about 80% of the materiovigilance reports, the actual causes of dysfunctions remain unexplained, which leads the AFSSAPS to classify the files as "no action", but without concluding that the device is safe. which leaves a presumption of failure.

This situation has serious consequences in terms of civil liability of the manufacturer of the medical device in question, and coverage of this risk with insurance companies. It is true that in other fields of activity, in particular in the air, road and maritime transport sector, recording devices are used, such as for example recorders of the flight parameters of aircraft, commonly designated as "black boxes". In this regard, reference may be made, for example, to US Pat. No. 6,392,692. However, the characteristics and the application of these recorders do not allow a direct adaptation to the field of surveillance of medical devices, such as insufflators medical.

European Patent Application No. EP 1 010 391 also discloses an interactive monitoring device between two microprocessors for controlling a medical device; this document does not have the direct purpose of recording the incidents of operation of a medical device.

Thus, there is still a need for specific systems for recording operating incidents of medical devices, and more particularly medical insufflators.

The present invention aims to provide such a system, to overcome the difficulties currently encountered, and exposed above.

For this purpose, the invention firstly relates to a method for recording the operating incidents of a medical device, constituted by a medical insufflator, this method essentially consisting of measuring, monitoring and permanently recording operating parameters of the device. the medical device concerned, in particular the dynamic or static pressure, by storing the measured parameters over a predetermined number of the last operating cycles of the apparatus or over a "sliding" period of operation of a predefined duration of this apparatus, and case of detection of an operating incident, to keep in memory the data recorded at the time of the occurrence of this incident, and, in case of detection of an operating incident, to keep in memory the data recorded at the time of the occurrence of this incident, the recorded data for a period extending before and after the occurrence of the incident, the method also comprising, during the commissioning of the medical device concerned, a detection of possible malfunctions of components of this device, and the recording of detected failures of components. Depending on the type of component malfunction detected, it can be reported to the user and / or order a temporary or permanent prohibition of the commissioning of the medical device concerned.

Thus, the method of recording operating incidents of medical devices, object of the invention, makes it possible to put under surveillance two types of events, namely:

- on the one hand, malfunctions of components, which are tested during the commissioning of the medical device,

- on the other hand, operational incidents occurring after the start of the medical device, knowing that this device must not be able to start in case of malfunction of a component essential for the safety of patients or users. In addition, both the component failures detected during the commissioning of the medical device and the incidents observed during operation of this device are stored, while also recording the moment of the memorized event. The recording of component failures will guide the after-sales service in the analysis of the malfunctions of the medical device concerned, and the recordings of operating incidents, stored in a secure manner, will enable the conditions to be fixed with certainty. occurrence of each incident and, as a result, the responsibilities of the practitioner and / or the manufacturer of the medical device. In addition, in the event of an incident involving a materiovigilance declaration after the AFSSAPS, the user may possibly be opposed to the fact that he has not made any corrective action, whereas a component failure has been reported, especially if the memorized date of this failure and its report is much earlier than the date, also stored, of the incident detected and reported to the AFSSAPS.

The aims of the invention, presented in the introduction, are therefore fully achieved, particularly with regard to the mandatory reporting of operating incidents and their conditions of occurrence.

In addition, the recordings of failures and incidents made may ^" provide for each medical device or category of medical devices concerned, analysis and knowledge necessary for the evolution of these devices and their software, in the sense of an improvement in their operation and reliability. A particularly advantageous aspect of the method which is the subject of the invention is that it ensures, after the start of the medical device concerned, a permanent storage of the only information concerning anomalies of certain parameters, in particular the information which precedes and immediately follows all incident, and which correspond to a duration of a few seconds or a few tens of seconds, which makes it possible to limit the size of the memories while benefiting from a maximum of useful information, the information considered as "normal" not being kept in memory.

The subject of the invention is also a device for implementing the method for recording medical device operating incidents previously defined, which essentially comprises electronic means for measuring the operating parameters of the medical device concerned, in particular relationship with a storage unit provided for, on the one hand, "sliding" the parameters measured over a predetermined number of last cycles or on a predefined operating time of the medical device and, on the other hand, memorizing permanently the data acquired at the time of the occurrence of an incident, the device further comprising means for testing the components of the medical device concerned, in connection with means for signaling component failures, and with the unit memory, also provided for recording the failures of the components.

This storage unit can be of any known type: so-called "EPROM" memory, hard disk, magnetic tape, etc.

In detail, the device stores the operating parameters measured over the last operating cycles of the medical device concerned, for example over three to ten cycles, which represents a permanent monitoring over a "sliding" period of at least 10 to 30 hours. seconds. By operating cycle is meant a series of phases of physical measurement of output data of the medical device, such as dynamic pressure, static pressure, pressure drop, flow rate, speed, voltage, intensity, etc., and calculation of control parameters of the medical device in order to reach the set values of the different outputs, followed by the application of the new calculated parameters. The stored data will be all the measurement and parameterization information of the medical device concerned. In the event of an incident, the values representative of the parameterization of the medical device and the physical output values of the same medical device are fixed in a part of the storage unit which is only accessible to the manufacturer or to accredited inspection bodies, to be noted preferably in the context of contradictory expertise.

In the event of a component malfunction detected during the commissioning of the medical device, ie as soon as it is switched on, the malfunction and its date are recorded (day the first finding of the failure of the component in question). Malfunctions of components that are essential for safety are signaled to the user by an automatic return of the medical device to "pause" or "standby" mode, with simultaneous display of an error code indicating the nature of the malfunction .

The normal functioning of the medical device can only be controlled after the preliminary tests of the components have been carried out, and in the event of a malfunction of an essential component, the device can not be operated in principle. However, in order to take account of certain random or fugitive failures, the medical device may restart after switching off and on again, provided of course that, during repeated tests during this power-up, no component failure is found. . However, such a situation will remain stored in the device, which will thus keep track.

We will now consider the normal operation of the medical device, as it occurs in the case where no malfunction of a component essential to safety has prohibited the start of this medical device. The storage unit then intervenes to record any operating incidents, that is to say to store the data present just before and just after the moment of occurrence of an operating incident, which also triggers a problem. alarm and / or causes the shutdown of the medical device, with or without counter-effect.

The data recorded and analyzed here are variable values associated with each parameterization of the device of control of the medical device / values established during sequences which generally represent times equal to or less than one second. In order to have a clear idea of the conditions for triggering an operating error, an analysis period of at least 10 seconds is in practice necessary. period extending before and after the occurrence of the incident. This involves, for example, recording the parameters of the five cycles that precede the appearance of an alarm, and also the parameters of the five cycles that follow the appearance of the alarm. This recording must also be dated, with appropriate precision, of the order of one second.

Beyond the recording of a particular operating incident, as described above, the storage unit of the device of the invention must be able to manage a minimum number of recordings of dated incidents, which may occur successively, for example ten recordings, in order to keep track of these incidents, even if the practitioner deems it essential and safe to continue his intervention, without interrupting the operation of the medical device.

At the moment of the recording of each incident, the device stores in particular, in association with the temporal data (date):

- the set values of the various parameters,

- the state of the various commands of the medical device, the state of the reports in progress other than the malfunctions of essential components,

values of the control parameters of the medical device,

- associated physical measurements during the cycles surrounding the incident.

In addition, in order to be able to identify external devices that disturb the operation of the medical device, in this case the medical insufflator, it is also necessary to memorize the physical measurements of the output of this device and their chronological evolution in "standby" mode. for example during the entire alarm phase.

Of course, the number of cycles recorded before and after each incident, as well as the number of incidents stored in memory, can be modified and adapted to each application case, in order to offer a better analysis relevance.

As a particular example of application of the invention, the following is considered the monitoring of incidents of operation of a medical insufflator, such as that subject of the aforementioned French patent application No. 2,716,627 , with reference to the attached schematic drawing. For the understanding of what follows, it is recalled that this is an insufflator for diagnostic and surgical endoscopy, which includes a circuit for insufflating a neutral gas such as carbon dioxide in an operating cavity, a controlled proportional flow rate controlled pneumatic valve being provided on this circuit, this valve being electrically powered. Means for measuring the insufflation pressure are provided at the head of the insufflation circuit, and the intracavitary pressure is calculated from the measured insufflation pressure, by means of an evaluation of the pressure loss of the circuit. A comparison is made between the intracavitary pressure thus determined, and a set value of this pressure, and the pneumatic valve is controlled according to the result of the comparison, to permanently provide a minimum gas flow rate, which strictly compensates for gas leaks. out of the operative cavity. As illustrated in FIG. 1, which is a diagram of the pressures as a function of time, the operation of this insufflator comprises an alternation of insufflation time, with measurement of dynamic pressure, and rest time, with measurement of a static or intracavitary pressure, to be compared with the set pressure. The insufflation time itself is subdivided into a succession of partial times, with increasing flow rates, until a dynamic pressure value equal to the setpoint pressure increased by an amount "Δp" is reached.

In the example considered, three significant operating parameters are monitored, which are respectively (with particular reference to the diagram of FIG. 1):

the instantaneous dynamic or static pressure P at points 1, 2, 3, A, B, C;

a coefficient k, which is a numerical control factor of the electric voltage applied to the proportional pneumatic valve of the insufflator, this coefficient being determined at points 1, 2 and 3 (it is zero at points A, B and C) ;

- the instantaneous gas flow D at points 1, 2 and 3 (this flow rate not being measured at points A, B and C).

The instantaneous pressure P and flow D, measured at each parameterization of the coefficient k, are kept in "sliding" memory for the last three parameterizations of this coefficient k.

In the event of an alarm with a stop of the insufflation, thus with disulphilation, the closing of the valve after de-airing causes the storage "frozen" of the characterizing values and the operating parameters for the three last cycles before stopping the insufflation, as well as values of the instantaneous pressures after stopping the insufflation, when opening the valve and closing it.

The different functions and phases of the operation of the insufflator, and the recording of failures and incidents, are also illustrated by the flowcharts of the following figures 2 to 5.

The flow diagram of Figure 2 illustrates the general operating loop of the insufflator.

The flowchart of FIG. 3 illustrates the test and calibration loop carried out before commissioning the insufflator. This involves testing all the functions, and acquiring various data, such as the voltage values (or the value of the aforementioned coefficient k) at the opening of the valve and at the closing of this valve, as well as the values of the operating hysteresis curve of said valve. It is also a question of calibrating the measuring points of the pressure P and of the flow D. This flow diagram indicates how, in the initialization phase, the observation of failures of essential components causes the non-starting of the insufflator, and the memorization of the malfunctions, accompanied by an error message.

The flowchart of FIG. 4 illustrates the regulator phase of the insufflator, in its normal operating cycle. "Smoothed" refers to the smoothed value of six pressure measurements taken at intervals of 0.15 seconds (in this example - see also Figure 1).

Finally, the flowchart of FIG. 5 illustrates the phase of measurement and storage of the operating incidents, for one of the parameters monitored, "measurement 1" denoting here the instantaneous pressure (measured at the six points 1, 2, 3, A, B, C, as indicated above). For the understanding of this last flowchart, it will be noted that:

- "delta 1" means the permissible overpressure before alarm, variable for example from 5 to 10 mm Hg;

- "delta 2" means the static pressure difference before restarting the insufflation; for example, the insufflation starts again as soon as the static pressure is equal to the setpoint, decreased by 1 mmHg (so in this example: -deKa-2- = (-1)).

Claims

1. A method for monitoring and recording operating incidents of a medical device, constituted by a medical insufflator, characterized in that it consists in measuring, monitoring and permanently recording operating parameters of the medical device concerned , in particular the dynamic or static pressure, and the gas flow, by storing the parameters measured over a predetermined number of the last operating cycles of the apparatus or over a "sliding" period of operation of the predefined duration of this apparatus, and, in the event of detection of an operating incident, to keep in memory the data recorded at the time of the occurrence of this incident, the recorded data relating to a period extending before and after the occurrence of the incident, the method comprising also, during the commissioning of the medical device concerned, a detection of possible malfunctions of components of this device and the recording of detected component failures.

2. Method according to claim 1, characterized in that a component malfunction is reported to the user and / or orders a temporary or permanent prohibition of the commissioning of the medical device concerned.

3. Method according to claim 2, characterized in that the malfunctions of essential safety components are signaled to the user by an automatic return of the medical device in "pause" or "standby" mode, with simultaneous display an error code indicating the nature of the malfunction.

4. Method according to claim 3 or 4, characterized in that, in order to take account of failures of random or fugitive nature, the medical device is provided to be able to restart after switching off and on again, such a situation still being memorized.

5. Method according to any one of claims 1 to 4, characterized in that the occurrence of an incident, during operation of the medical device, triggers an alarm and / or causes the shutdown of the medical device, with or without counter-effect.

6. Method according to any one of claims 1 to 5, characterized in that at the moment of recording of each incident, are stored in particular, in association with the temporal data:

- the set values of the various parameters,

- the state of the different commands of the medical device,

- the status of pending reports other than malfunctions of essential components,

values of the control parameters of the medical device,

- associated physical measurements during the cycles surrounding the incident.

7. Method according to claim 6, characterized in that are also memorized the physical output measurements of the medical device and their chronological evolution in "standby" mode, for example during the entire alarm phase.

8. Device for recording the operating incidents of a medical device, for implementing the method according to any one of claims 1 to 7, characterized in that it comprises electronic means for measuring the operating parameters. of the medical device concerned, in connection with a storage unit provided for, on the one hand, "sliding" the parameters measured over a predetermined number of last cycles or on a predefined operating time of the medical device and, on the other hand, permanently store the data acquired at the time of the occurrence of an incident, and in that it still comprises means for testing the components of the medical device concerned, in relation to means reporting of component failures, and with the aforementioned storage unit, which is also provided for recording component failures.

9. Device according to claim 2, characterized in that the storage unit is provided to manage a minimum number of records of incidents dated, which may occur successively.