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#49 P11073-10721™/D1 - Introduction
P11073-10721™/D1
Draft Standard for Device Specialization - High Frequency (200 kHz to < 5 MHz) Surgical Equipment
6. Introduction
6.1 HF SURGICAL EQUIPMENT Device Concepts and Operational Concepts
Device Concepts
HF SURGICAL EQUIPMENT is MEDICAL ELECTRICAL EQUIPMENT which delivers HIGH FREQUENCY currents to perform surgical modification of tissue. The most common forms of tissue modification are CUTTING and COAGULATION but may also include tissue ablation, lesioning, shrinkage, sealing or fusion.
The HF current is conducted to and from the PATIENT in the following ways:
- in MONOPOLAR application with an ACTIVE ELECTRODE of a small area and a large NEUTRAL ELECTRODE;
- in MONOPOLAR application of HF SURGICAL EQUIPMENT with a RATED OUTPUT POWER less than 50 W and not provided with a NEUTRAL ELECTRODE connection point, the circuit for the HIGH FREQUENCY current being completed through the capacitive coupling between the PATIENT and the earthed environment;
- in BIPOLAR application with a BIPOLAR electrode only, for example forceps where the legs are electrically insulated from each other;
- in multipolar application where a multitude of ACTIVE ELECTRODES are present. In this type of application the current passes from one or more of the ACTIVE ELECTRODES to either a large NEUTRAL ELECTRODE in a MONOPOLAR like arrangement or to one or more small area electrodes in the immediate vicinity in a BIPOLAR like arrangement;
- in an application where the current delivery is augmented by the use of argon gas or saline solution between the ACTIVE ELECTRODE(S) and the target tissue.
The output power may vary considerably depending on the intended use, from a few watts for special procedures, for example in ophthalmology, up to 300 W or more for some equipment. The peak output voltage from some equipment may be as high as 6 000 V or more.
Operational Concepts
Currently available devices can be distinguished between "ACTIVE ACCESSORY-oriented" and "ACTIVE OUTPUT TERMINAL-oriented".
Using the so-called "ACTIVE ACCESSORY-oriented" approach, all parameters are directly related to the ACTIVE ACCESSORY. This means that the user directly configures the settings of the ACTIVE ACCESSORY used for the surgery. For example, the settings of bipolar forceps or a monopolar electrode handle with ball electrode are configured independently from the ACTIVE OUTPUT TERMINAL they are plugged in or will be plugged in, respectively. For the configuration it does not matter whether the ACTIVE ACCESSORY is plugged to an ACTIVE OUTPUT TERMINAL or not. If the ACTIVE ACCESSORY is connected, the VmdState/PhysicalConnector element of the VIRTUAL TERMINAL VMD is used to model the association between ACTIVE ACCESSORY and ACTIVE OUTPUT TERMINAL. Note that it is typically possible to plug an ACTIVE ACCESSORY to different ACTIVE OUTPUT TERMINALs. The number of VIRTUAL TERMINALs represents the number of configurable ACTIVE ACCESSORYs. If a monopolar ACTIVE ACCESSORY is selected, the GENERAL HF OUTPUT PARAMETER CHANNELs modelling the bipolar parameters are deactivated and vice versa.
Using the so-called "ACTIVE OUTPUT TERMINAL-oriented" approach, all parameters are directly related to the ACTIVE OUTPUT TERMINAL. Nowadays, this might be the common way of interaction. The user configures a particular ACTIVE OUTPUT TERMINAL to be used for example with plugged bipolar forceps or a monopolar electrode handle with ball electrode. Consequently, the ACTIVE ACCESSORY has to be plugged to this particular ACTIVE OUTPUT TERMINAL.
There is a static assignment between VIRTUAL TERMINAL and ACTIVE OUTPUT TERMINAL. Thus, the VmdState/PhysicalConnector element describes the static ACTIVE OUTPUT TERMINAL the VIRTUAL TERMINAL represents. The number of VIRTUAL TERMINALs equals to the number of available ACTIVE OUTPUT TERMINAL. For monopolar ACTIVE OUTPUT TERMINALs, the GENERAL HF OUTPUT PARAMETER CHANNELs modelling the bipolar parameters are omitted in the CONTAINMENT TREE or deactivated at STATE level.
Additionally, there are devices covering aspects of both operating concepts. For example, if ACTIVE ACCESSORIES are able to identify themselves at a device that are basically ACTIVE-OUTPUT-TERMINAL-oriented, this can bring aspects of the ACTIVE-ACCESSORY-oriented approach to these devices.
Diff:
Diff:
[tCon 26.05.2020]
Add references and additional documents/information:
text for Device Concepts updated and note added according to todays webex meeting:
**Device Concepts **
HF SURGICAL EQUIPMENT is MEDICAL ELECTRICAL EQUIPMENT which delivers HIGH FREQUENCY currents to perform surgical modification of tissue. The most common forms of tissue modification are CUTTING and COAGULATION but may also include tissue ablation, lesioning, shrinkage, sealing or fusion.
In today's common HF SURGICAL applications, the HF current is conducted to and from the PATIENT in the following ways:
– in MONOPOLAR application with an ACTIVE ELECTRODE of a small area and a large NEUTRAL ELECTRODE. The current flow over the small area of the ACTIVE ELECTRODE leads to a high current density at the target tissue and therefore induces the intended thermal effect, whereas the low current density at the large NEUTRAL ELECTRODE site prevents thermal effects;
– in MONOPOLAR application of HF SURGICAL EQUIPMENT with a RATED OUTPUT POWER not in excess of 50 W and not provided with a NEUTRAL ELECTRODE connection point, the circuit for the HIGH FREQUENCY current being completed through the capacitive coupling between the PATIENT and the earthed environment;
– in BIPOLAR application with a BIPOLAR electrode only, for example forceps where the legs are electrically insulated from each other;
– in multipolar application where a multitude of ACTIVE ELECTRODES are present. In this type of application the current passes from one or more of the ACTIVE ELECTRODES to either a large NEUTRAL ELECTRODE in a MONOPOLAR like arrangement or to one or more small area electrodes in the immediate vicinity in a BIPOLAR like arrangement;
– in a MONOPOLAR application where the current delivery is augmented by the use of argon gas between the ACTIVE ELECTRODE and the target tissue.
– in a BIPOLAR or multipolar application where the current delivery is augmented by the use of saline solution between the ACTIVE ELECTRODES and the target tissue.
The output power may vary considerably depending on the intended use, from a few watts for special procedures, for example in ophthalmology, up to 300 W or more for some equipment. The peak output voltage from some equipment may be as high as 6 000 V or more.
...
Note:
For more and detailed information see:
IEC 60601-2-2: Particular requirements for the basic safety and essential performance of high frequency surgical equipment and high frequency surgical accessories
IEC/TR 61289: High frequency surgical equipment and high frequency surgical accessories - Operation and maintenance
[tCon 02.06.2020]
Consensus -> doc-me
Fine-tuned Operational Concepts paragraph:
Operational Concepts
Currently available devices can be divided into the two main groups "ACTIVE ACCESSORY-oriented" devices and "ACTIVE OUTPUT TERMINAL-oriented" devices.
Using the so-called "ACTIVE ACCESSORY-oriented" approach, operational parameters are directly related to the ACTIVE ACCESSORY. This means that the user directly configures the settings of the ACTIVE ACCESSORY used for the surgery. For example, the settings of bipolar forceps or a monopolar electrode handle with ball electrode are configured independently from the ACTIVE OUTPUT TERMINAL to which the ACTIVE ACCESSORY is or will be connected. For the configuration it does not matter whether the ACTIVE ACCESSORY connected to an ACTIVE OUTPUT TERMINAL or not. If the ACTIVE ACCESSORY is connected, the VmdState/PhysicalConnector element of the VIRTUAL TERMINAL VMD is used to model the dynamic association between ACTIVE ACCESSORY and ACTIVE OUTPUT TERMINAL. Note that it is typically possible to connect an ACTIVE ACCESSORY to different ACTIVE OUTPUT TERMINALs. The number of VIRTUAL TERMINALs represents the number of configurable ACTIVE ACCESSORYs. If a monopolar ACTIVE ACCESSORY is selected, the GENERAL HF OUTPUT PARAMETER CHANNELs modelling the bipolar parameters are deactivated and vice versa.
Using the so-called "ACTIVE OUTPUT TERMINAL-oriented" approach, operational parameters are directly related to the ACTIVE OUTPUT TERMINAL. Nowadays, this might be the common way of interaction. The user configures a particular ACTIVE OUTPUT TERMINAL to be used with a certain ACTIVE ACCESSORY, for example bipolar forceps or a monopolar electrode handle with ball electrode. Consequently, the respective ACTIVE ACCESSORY has to be connected to this particular ACTIVE OUTPUT TERMINAL. There exists a static one-to-one realtionship between VIRTUAL TERMINAL and ACTIVE OUTPUT TERMINAL, so the number of VIRTUAL TERMINALs equals the number of available ACTIVE OUTPUT TERMINALs. Thus, the VmdState/PhysicalConnector element describes the static ACTIVE OUTPUT TERMINAL the VIRTUAL TERMINAL represents. For MONOPOLAR ACTIVE OUTPUT TERMINALs, the GENERAL HF OUTPUT PARAMETER CHANNELs modelling the bipolar parameters are omitted in the CONTAINMENT TREE or deactivated at STATE level.
Additionally, there are devices covering aspects of both operating concepts. For example, if ACTIVE ACCESSORIEs are able to identify themselves at a device that are basically ACTIVE-OUTPUT-TERMINAL-oriented, this can bring aspects of the ACTIVE-ACCESSORY-oriented approach to these devices.
Text acknowledged by experts.