(163 days)
Pajunk's MultiStim ECO is intended for nerve stimulation during anaesthesia delivery; first for identification of peripheral nerves and second for localizations. This device is indicated for adults only.
PAJUNK® GmbH Medizintechnologie is submitting this 510(k) for the MultiStim ECO handheld, battery powered peripheral nerve stimulator.
The MultiStim ECO is a nerve stimulator that is suitable for stimulation technique. It is characterized in particular by the following properties:
- small, compact device complies with the requirements of combined procedures -
- -Simple operation - manual settings are limited to the parameters proven in practice
- -No additional patient cable - cannula is directly connected to the device
The MultiStim ECO settings are adapted to standard applications as well as the intuitively operated keyboard enable one-hand operation. A keystroke is all that is necessary for activation after switching on - an additional function selection is not required.
Basic functions/ features:
Fixed defined settings:
The frequency is predefined at 1 Hz and the stimulation pulse width at 0.1 ms.
Due to safety reasons, stimulation is first activated by a touch of the stimulation button.
Variation of the current strength
Depending on the special requirements of an application, the current strength can be gradually set on a six-level amplitude scale from 0.2 to 2.0 mA. Arrow buttons are used for the plus/minus key.
Fixation by an adhesive electrode
The MultiStim ECO has a pushbutton connection on the lower side of the device and is clicked directly on the adhesive electrode. The stimulateable cannula is connected directly to the MultiStim ECO.
The provided text is a 510(k) summary for the MultiStim ECO, a peripheral nerve stimulator, seeking substantial equivalence to the MultiStim SENSOR. The document focuses on demonstrating that the new device performs as effectively as the predicate device.
Here's an analysis of the acceptance criteria and the study proving the device meets them, based on the provided text:
Acceptance Criteria and Reported Device Performance
The core of the performance acceptance criteria appears to be the congruence of output graphs between the MultiStim ECO (subject device) and the MultiStim SENSOR (predicate device) across various current (mA) settings. The device's performance is tested against specific current outputs and the corresponding voltage (mV).
Table of Acceptance Criteria and Reported Device Performance:
| Current (mA) | Expected Voltage (mV) for Congruence | Reported Device Performance (MultiStim ECO Output Voltage) | Outcome of Comparison |
|---|---|---|---|
| 0.2 | Approx. 202 | 202 | Congruent |
| 0.5 | Approx. 500 | 500 | Congruent |
| 0.7 | Approx. 712 | 712 | Congruent |
| 1.0 | Approx. 1000 | 1000 | Congruent |
| 1.5 | Approx. 1520 | 1520 | Congruent |
| 2.0 | Approx. 2040 | 2040 | Congruent |
Additional Implicit Acceptance Criteria:
- Identical Intended Use: The MultiStim ECO must have the same intended use as the MultiStim SENSOR. This is explicitly stated and claimed to be identical, with a minor change in wording ("percutaneous" removed as obsolete).
- Identical Basic Technical Description Relevant to Clinical Use: The fundamental method of impulse generation (quartz crystal) and the non-software hardware solution are presented as core to this.
- Compliance with Recognized Standards: The device must meet a comprehensive list of IEC/EN standards for medical electrical equipment, including safety, electromagnetic compatibility, usability, and specific requirements for nerve and muscle stimulators. (See the list of standards provided on pages 10-11).
- Physical and Functional Equivalence (where applicable): Various characteristics like dimensions, FDA classification, product code, biocompatibility, power supply, pulse form, and protection type are compared, and deviations are rationalized as either equivalent or improvements/simplifications that do not negatively impact safety or effectiveness.
Study Details Proving Acceptance Criteria
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Sample Size and Data Provenance:
- Test Set Sample Size: The document does not specify a "sample size" in terms of number of devices tested. It describes a bench test where "the output signals of values which are adjustable at the MultiStim ECO have been compared to those with the same settings at the MultiStim SENSOR." This implies testing of at least one MultiStim ECO device against a MultiStim SENSOR for the specified current settings. There is no indication of a large-scale clinical trial or patient data.
- Data Provenance: The data is generated from bench testing ("the desired signal combination was adjusted and visualized with an oscilloscope"). The location of the test is not specified, but the manufacturer is based in Germany. The data is prospective in the sense that it was generated for this submission to verify performance.
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Number of Experts and Qualifications for Ground Truth:
- This submission does not involve experts establishing ground truth in the typical sense of clinical image review or diagnostic performance. Instead, the "ground truth" is established by the engineering specifications and the measured output of the predicate device (MultiStim SENSOR), which is itself a legally marketed device. The comparison is objective, based on instrument readings (oscilloscope).
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Adjudication Method for the Test Set:
- Not applicable. This was a bench test with objective measurements and comparison to a known standard (predicate device output).
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Multi Reader Multi Case (MRMC) Comparative Effectiveness Study:
- No MRMC study was done. This device is a nerve stimulator, not an imaging AI or diagnostic aid that would typically involve human readers interpreting results. The comparison is at the engineering/performance level, not human-in-the-loop effectiveness.
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Standalone Performance:
- Yes, a standalone (algorithm only without human-in-the-loop performance) was done. The core performance testing involved measuring the output signals of the MultiStim ECO device in isolation and comparing them to those of the predicate device, using an oscilloscope. This is purely a device performance assessment independent of human interpretation or use in a clinical setting.
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Type of Ground Truth Used:
- The "ground truth" is the measured output characteristics (voltage at specific current settings and pulse shape) of the predicate device (MultiStim SENSOR), along with compliance to relevant medical device standards (e.g., consistency of square pulse form, 1Hz frequency, 0.1ms pulse width). It's an engineering/device specification ground truth, not a clinical outcome or pathology report.
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Training Set Sample Size:
- Not applicable. This is a hardware device without a "training set" in the context of machine learning or AI algorithms. The device's design is based on established electrical engineering principles and the performance of its predicate.
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How Ground Truth for Training Set was Established:
- Not applicable, as there is no "training set." The design and "training" (if one could use the term loosely) of the device come from established medical device engineering practices and the existing predicate device.
§ 868.2775 Electrical peripheral nerve stimulator.
(a)
Identification. An electrical peripheral nerve stimulator (neuromuscular blockade monitor) is a device used to apply an electrical current to a patient to test the level of pharmacological effect of anesthetic drugs and gases.(b)
Classification. Class II (performance standards).