STIMPOD NMS410 & 450 User Manual rev 1.00

Manufacturer Xavant Technology PTY (LTD) 169 Garstfontein Road Ashlea Gardens, 0081 Pretoria South Africa Tel: Fax: E-mail: Web:

+27 (0) 12 755 9491 +27 (0) 86 547 0026 [email protected] www.xavant.com

Legal Representative in the EU Emergo Europe 15 Molenstraat, 2513 BH, The Hague The Netherlands Tel: +31 70 345 8570 Fax: +31 70 346 7299

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Indications for use:

This product is a nerve stimulation device designed to be used by an anesthetist during regional anesthesia for the purpose of • Nerve mapping using the non-invasive Nerve Mapping Probe (supplied) and • Nerve locating using invasive electrodes/needles (not supplied) • General Anesthesia, for the purpose of establishing the efficacy of a Neuromuscular Blocking Agent using non-invasive surface electrodes (not supplied). (NMS450)

Contraindications:

• Infection of the puncture site • Known neurological disorders • Severe Coagulation disorders

Warnings:

• Read the entire User Manual before attempting to use the device. • Use of cables or accessories other than those supplied with the STIMPOD may result in serious injury. • Maintenance on this device may only be performed by the manufacturer or persons explicitly authorized by the manufacturer. • Do not use the STIMPOD in close proximity to equipment that produces strong electromagnetic fields, such as high frequency surgical equipment. The cable leads could act as antennae and dangerous currents could be induced as a result. • Do not apply the STIMPOD to patients with implanted electrical devices, such as cardiac pacemakers, without first consulting with an appropriate medical specialist.

Cautions:

• Remove elements which may adversely affect the connection between the ecg electrodes and the skin, ie: dirt, hair, oil. • Ensure that ECG electrodes are not damaged or dried out. • ECG electrodes may be used in the higher current ranges (> 10 mA). • This product must be stored at room temperature. • This product must be transported in the carry case provided. • This product and all the accessories have been certified latex free.

Warranty:

• The Stimpod carries a 12 Month Warranty against defects, provided that the device was used in accordance with the operating instructions. • The Stimpod enclosure should not be opened under any circumstances. Opening the unit will void the warranty.

STIMPOD (NMS410/450) conforms to the following standards:

• IEC 60601-1, IEC 60601-2-10 • IEC 60601-1-2: CISPR 11 Group1 class B; IEC 61000-4-2; IEC 61000-4-3 • ISO 13485, Directive 93-42-EEC

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Contents 1.

Getting to know the STIMPOD (NMS 410/450)

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1.1) 1.2) 1.3) 1.4) 1.5) 1.6) 1.7) 1.8) 1.9) 1.10)

Device Description Special Features Accessories Device Layout Screen Layout Open Circuit Detection Combined Nerve Mapping/Locating Mode Sound Auto Shutdown Symbols on device battery clip

1 2 3 4 5 7 7 8 8 8

2.

Operating device in Nerve Locating Mode (NMS 410/450)

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2.1) 2.2) 2.3) 2.4) 2.5)

Adjusting the Current Adjusting the Pulse Width Adjusting the Twitch Frequency Diagnostic Screen Proximity Indicator

10 10 10 11 11

3.

Operating device in Nerve Mapping/Locating Mode (NMS 410/450)

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3.1) 3.2) 3.3) 3.4)

Adjusting the Current Adjusting the Pulse Width Adjusting the Twitch Frequency Diagnostic Screen

13 13 13 14

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Contents 4.

Operating device in Neuromuscular Blocking Agent (NMBA) Monitoring Mode (NMS 450)

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4.1) 4.2) 4.3) 4.4) 4.5) 4.6) 4.7) 4.8) 4.9) 4.10) 4.11)

Adjusting the Current Adjusting Stimulation Mode Adjusting the Twitch/ Tetanus Frequency Electrode Placement Accelerometer Placement Single Stimulus vs. Repeated Stimulation Train of Four Mode (TOF) Double Burst Mode (DB) Post Tetanic Count Mode (PTC) Tetanus Mode Twitch Mode

16 16 16 16 16 17 17 17 18 18 19

5.

Setting Up Device Defaults

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5.1) 5.2) 5.3) 5.4) 5.5) 5.6) 5.7) 5.8) 5.9)

Languages Current Mode Pulse Width Options Stimulating Frequency Repeat Timer Proximity Indicator Speaker Volume Backlight User Information

21 22 27 27 28 28 29 30 31

6.

Specifications

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6.1) 6.2)

Specifications Cleaning and Disinfecting STIMPOD

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1) Getting to know the STIMPOD (NMS 410/450) 1.1)

Device Description

The STIMPOD (NMS 410/450) is a precision nerve locating tool used for localizing specific neural path ways. Localization of nerves by electrical stimulation involves connecting the nerve stimulator to a conducting needle through which local anaesthetics can be injected. The distance of the needle (cathode) from the nerve can be estimated by establishing the minimum threshold current required, to facilitate a neuromuscular response. The STIMPOD (NMS 450) includes Neuromuscular Blocking Agent Monitoring functionality with real-time feedback achieved by tri-axial accelerometery. CAUTION: This device should only be used by a qualified physician with appropriate knowledge in regional anaesthesia. CAUTION: The sale or purchase of the device is restricted to licensed medical practitioners, as governed by the law of the country/ state in which he/ she practices, or where the device is to be used.

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1.2)

Special Features

User interface: • Four high quality membrane-switch Buttons and a capacitive sensing Wheel form a simple and intuitive keypad layout. • All device parameters displayed. • Visual and Auditory stimulation feedback. Waveforms: • The STIMPOD offers superior performance in terms of stimulus shape, linearity and consistency. Attachment Clip: • Designed to serve as a stand, hook, or a clip. This clip offers a versatile and ergonomic solution to secure device placement. Diagnostics Screen: • Displaying real-time feedback on the shape of the actual delivered stimulus as well as average current and charge delivered. A warning notifies the user if the calculated averages differs from the current setting. Proximity Range: • Visual and auditory feedback is given when the target current- and pulse width ranges are reached. Non–Linear Adjustment: • Choose between Linear (normal) and Non-Linear progression of current and pulse width settings. Non – Linear mode allows the user to customize 20 current and pulse width setting positions. Cable Recognition: • The Stimpod recognizes the respective cables plugged into it and activates the appropriate stimulating modes. Nerve Mapping Probe: • The ergonomic Nerve Mapping Probe presents the user with a simple and reliable Nerve Mapping solution. The surgical steel tip is small enough to provide good neuronal selectivity while still providing enough contact surface to minimize current densities. Tri-axial Accelerometery (NMS 450) • The NMS 450 offers real-time feedback of the efficacy of Neuromuscular Blocking Agents by means of tri-axial accelerometery, measuring relative contraction strengths.

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1.3)

Accessories

WARNING: Use of cables or other accessories other than those supplied with the STIMPOD may result in serious injury. NOTE: ECG Electrodes and Nerve Locating needles are not included in this package.

Nerve Locating Cable: This cable is used to activate the Nerve Locating mode on the STIMPOD. The red (anode) connector is designed to clip onto a standard ECG electrode. The needle connector will accommodate various makes of needles.

Nerve Mapping / Nerve Locating Cable: This cable is used to activate the Nerve Mapping/ Nerve Locating mode on the STIMPOD. The red (anode) connector is designed to clip onto a standard ECG electrode. The ergonomically designed cutaneous Nerve Mapping Probe presents the user with a simple and reliable Nerve Mapping solution. The needle connector will accommodate various makes of needles.

NMBA Monitoring Cable (NMS450): This cable is used to activate the NMBA mode on the STIMPOD. The red (anode) and black (cathode) connectors are designed to clip onto standard ECG electrodes. The blue accelerometer is designed to attach to the contracted appendage (in the case of the ulnar nerve, this will be the thumb).

CAUTION: A sterile wipe should be applied to the Nerve Mapping Probe prior to use. Batteries: The unit uses 4 x AAA penlight batteries. Alkaline batteries are recommended. When the battery is depleted the unit will prompt the user to replace the battery and switch off. Switch device off before replacing battery. Remove battery if the device is not to be used for an extended period of time, to prevent leakage.

Carry Case WARNING: If battery acid has leaked into the device essential circuitry may have been compromised. In the event of leakage the device must be returned to its manufacturer for safety checks and possible repairs.

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1.4)

Device Layout

Cable Connector Insert the Nerve Locating Cable or the combined Nerve Locating/Mapping Cable to activate the relevant Mode.

Enter / Frequency Button

Display

Multi Functional Clip

Press to toggle between Frequencies. Press to Enter in setup menu.

Menu/ Pulse Width Button NMS 410/450 (LOC/MAP Mode) Press to toggle between Pulse Widths. Press and hold to access Setup Menu.

NMS 450 (NMBA Mode) Press to toggle between Stimulation Modes.

Stimulating LED indicator Flashing Green: Stimulus delivered. Flashing Red: Open Circuit.

Pause Button NMS 410/450 (LOC/MAP Mode) Press to Start/ Stop Stimulation.

NMS 450 (NMBA Mode) Press and release to elicit a single stimulation. Press and hold for two seconds to initiate/ stop continuous stimulation.

The Wheel

Battery Compartment Cover

Adjust current in the main operating mode. Navigate the Setup Menus.

On / Off Button Press to switch unit on. Press and hold to switch unit off.

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1.5)

Screen Layout

Indicators Nerve mapping mode

Non-Linear map Linear map

Nerve locating mode NMBA mode (NMS450)

Speaker Volume

Battery Status

LOC MAP

Main Screen Current Setting (Adjust using Wheel)

0.90mA

LOC

0.90mA

Average current of actual stimulus

Diagnostics or Warning Screen Pulse Width Setting

(Adjust using Menu/ Pulse Width button)

Warning Screens

0.1ms

1 Hz

NMBA Mode (NMS 450)

Stimulating Frequency Setting

(Stimulation Mode: TOF, DB, PTC, TET, TWI)

(Adjust using Enter/Hz button)

TOF Diagnostic Screen NMS 410/450 (LOC/MAP Mode) Proximity indicator arrow

Calculated Charge Setting

Indication of current setting

0.09uC

0 mA Graph indicating shape of actual current stimulus

Warning (Notifies the user of a discrepancy between current settting and avarage current of actual stimulus)

Diagnostic Screen NMS 450 (NMBA Mode) Real-time feedback of relative contraction strength as measured with the accelerometer

Countdown timer for repeat mode

00:36

100%

0.09uC

Average charge of actual stimulus

Calculated percentage in TOF and DB mode Twitch Count in PTC and TOF if less than 4 contractions were identified 5

Warning Screens

Insert Cable

Insert Cable: This is the first prompt which the user will encounter as the unit is switched on, and signals that the unit is waiting for the cable to be inserted.

PAUSE: This warning informs the user that the PAUSE button was pressed. The STIMPOD will pause all its activities and wait for, the PAUSE button to be pressed again.

Cable Not Recognised

Cable not recognized: This warning informs the user that the inserted cable is not compatible with the NMS 400.

Replace Batteries: This warning informs the user that the batteries are depleted beyond an acceptable level. Continuing to operate the device thus will make it unreliable. To prevent this the STIMPOD flashes this warning for 4 seconds before switching off.

Open Circuit Detected

PAUSE

Replace Batteries

Open Circuit Detected: This warning informs the user that the two electrodes (ie. Ecg electrode and needle or mapping device) do not form a closed circuit. This warning will be accompanied by a red flashing LED, every time the unit attempts to stimulate.

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1.6)

Open Circuit Detection

A few milli seconds prior to the actual stimulation, an impedance measurement is made to detect whether the connection between the STIMPOD and the patient comprises a closed circuit.

Open Circuit Detected

Closed Circuit Detected:

Open Circuit Detected:

Stimulation will take place

No stimulation will take place.

Stimulating sound will be heard (Single or multiple beeps depending on

No stimulating sound will be heard.

proximity indicator settings. Sound pitch will follow the current intensity).

The LED stimulus indicator will pulse red with every unsuccessful

The LED stimulus indicator will pulse green with every successful

stimulus attempt.

stimulus attempt.

A warning screen will appear in the diagnostics screen indicating that

The diagnostics screen will provide active feedback on every pulse delivered.

an open circuit was detected.

1.7)

Combined Nerve Mapping/Locating Mode

When using the mapping/locating cable: • The STIMPOD will always default on Mapping Mode. • When the needle penetrates the patient, STIMPOD will sense it and switch to Locating Mode. • If the needle is disconnected from the patient, and the mapping probe touches the patient, STIMPOD will sense it and switch back to Mapping Mode. • Whenever both the needle and the probe touches the patient, the needle will have highest priority and the STIMPOD will switch to Locating Mode.

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1.8)

Sound

If sound is enabled: • STIMPOD will beep every time that a stimulus was delivered. • The pitch of the sound will follow the current intensity level. If the proximity indicator is activated: • A successful stimulus above the proximity range will make a single beep. • A successful stimulus within the proximity range will make a double beep. • A successful stimulus below the proximity range will make a triple beep.

1.9)

Auto Shutdown

STIMPOD will shutdown after 10 minutes of no user or patient interaction.

1.10)

Symbols on device battery clip

Manufacturer

Attention! See Instructions for Use

Separate collection for electrical and electronic equipment (Applicable to EU community only)

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Manufacturing Date (Year)

SN

EC REP

Serial Number

Representative in the EU

2) Operating device in Nerve Locating Mode (NMS 410/450) Localization of nerves by electrical stimulation involves connecting the nerve stimulator to a conducting, locating needle (not supplied) through which local anaesthetics can be administered. This procedure involves subcutaneous stimulation of the motor component of the relevant peripheral nerve, to ‘locate’ the nerve. Select this mode by inserting the Nerve Locating cable. The STIMPOD will automatically default to the Nerve Locating current range (0.00 – 5.00 mA) and display the ' ' indicator.

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2.1)

Adjusting the Current Current Mode Options:

Options in the Setup Menu: Linear Mode, Non-Linear Mode Default: Linear

Linear Mode:

Non - Linear Mode:

The Linear Mode is called linear because one 'click' on the Wheel will correspond With one increment as set in the specific current range. The Linear Mode allows the user to select individual incrementing options for the three different current ranges.

The Non-Linear Mode facilitates the non-linear nature of the current intensity versus the distance from the nerve as discussed in section 6.8 (Stimulus Intensity vs. Distance from Nerve). This mode allows the user to define 20 adjustment positions in terms of Current (mA) and Pulse Width (ms). If correctly implemented each adjustment position should afford the user with a relatively linear progression in terms of the distance from needle tip to the nerve.

Default Current range: 0.00 - 5.00 mA adjustable in the following default increments: 0.00 – 0.60 mA Default: 0.1 mA increments 0.6 – 2.0 mA Default: 0.1 mA increments 2.0 – 5.0mA Default: 0.2 mA increments

Default Current and Pulse Width Range: As shown in table 5.1 in section 5.2 circle the Wheel to select the predetermined current and pulse width positions sequentially.

Increments can be adjusted in the Setup Menu (refer to 5.2) Circle the Wheel to adjust current. Warning (Notifies the user of a discrepancy between current settting and avarage current of actual stimulus) Average of actual current delivered.

2.2)

Adjusting the Pulse Width

NOTE: Because the 20 definable positions include both

0.90mA

LOC

0.90mA

current and pulse width settings, pulse width cannot be adjusted independently in this mode. This is indicated on the screen by the fact that pulse width is not highlighted.

0.1ms 0.1ms

1 Hz

2.3) Adjusting the Twitch Frequency

Options in the Setup Menu: 0.05ms, 0.1ms, 0.3ms, 0.5ms, 1ms Default: 0.1ms, 0.3ms

Options in the Setup Menu: 1Hz, 2Hz, 5Hz Default: 2Hz

Press Menu/Pulse Width button to toggle between different Pulse Widths

Press Enter/Hz button to toggle between different stimulating frequencies.

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2.4)

Diagnostics Screen

The diagnostics screen offers the user qualitative real-time feedback of:

0.09uC 0.09uC

Calculated Charge Setting

NOTE: Adjusting the Current and or Pulse Width will also affect the total charge delivered per pulse. This charge is shown next to the current display, and is measured in µC (micro Coulomb) Average of actual charge delivered.

2.5)

Proximity Indicator

The proximity indicator is activated when the combination of current and pulse width settings result in a charge which is within the range as selected in the SETUP MENU, section 5.5.

Visual Indication:

0.09

Visually indicated in the diagnostics screen by two arrowheads.

Arrowhead indicating the lower threshold points upwards.

Arrowhead indicating the upper threshold points downwards.

The dotted line representing the selected current will be positioned between the two

arrowheads if the target charge range is entered.

0.09uC 0.09uC

Audible Indication: A successful stimulus above the proximity range will make a single beep. A successful stimulus within the proximity range will make a double beep. A successful stimulus below the proximity range will make a triple beep.

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3) Operating device in Nerve Mapping/ Locating Mode (NMS 410/450) Percutaneous nerve mapping enables the anesthetist to map out a particular superficial nerve prior to nerve location with the needle. This is accomplished by stimulating the motor component of the relevant peripheral nerve percutaneously with the nerve mapping probe. This technique ensures a higher success rate for directing the needle to the correct nerve. This mode offers the user the means to do nerve mapping and locating without having to switch or unplug cables. When inserting the Nerve Mapping/ Locating cable, the STIMPOD will default to the Nerve Mapping current range (1-20 mA). Current will be directed to the Nerve Mapping probe and the STIMPOD will attempt to stimulate. The moment that the needle penetrates the skin the cable will sense it and inform the STIMPOD. The STIMPOD will switch to Nerve Locating mode and behave as described chapter 2. If contact between the needle and patient is broken, and the nerve mapping probe touches the patient, STIMPOD will switch back to the nerve mapping mode and start monitoring the needle - patient connection again. Whenever the nerve mapping probe and the nerve locating needle simultaneously make contact with the patient the needle will have first priority. This mode is selected when the Nerve Mapping/Locating cable is inserted.

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When using the Nerve Mapping Probe NMS 410/450: The STIMPOD will automatically default to the Nerve Mapping current range (0-20mA) and display the ‘

3.1)

Adjusting the Current

Current Range: 0 – 20 mA adjustable in 1mA increments.

10 mA

MAP

10.2mA

Average of actual current delivered. Warning (Notifies the user of a discrepancy between current settting and avarage current of actual stimulus)

1.00uC

Circle the Wheel to adjust current.

1.02uC

0.1ms 3.2)

‘ indicator.

1 Hz

Adjusting the Pulse Width

3.3)

Adjusting the Twitch Frequency

Options in the Setup Menu: 0.05ms, 0.1ms, 0.3ms, 0.5ms, 1ms Default: 0.1ms, 0.3ms

Options in the Setup Menu: 1Hz, 2Hz, 5Hz Default: 2Hz

Press Menu/Pulse Width button to toggle between different pulse widths.

Press Enter/Hz button to toggle between different stimulating frequencies.

When using the Nerve Locating Needle Connect the needle to the Nerve Mapping/ Locating cable. The moment that the needle penetrates the skin the cable will communicate this to the STIMPOD, switch to nerve locating mode, and switch the stimulation to the needle. The current in locating mode will default to 0.00mA. The STIMPOD will now function exactly as described in Chapter 2. If contact between the needle and patient is broken, and the nerve mapping probe touches the patient, STIMPOD will switch back to the nerve mapping mode and start monitoring the needle - patient connection again. Mapping mode will default back to 0mA. Whenever the nerve mapping probe and the nerve locating needle simultaneously make contact with the patient the needle will have first priority.

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3.4)

Diagnostics Screen

The diagnostics screen offers the user qualitative real-time feedback of:

1.00uC 1.02uC

Calculated Charge Setting

NOTE: Adjusting the Current and or Pulse Width will also affect the total charge delivered per pulse. This charge is shown next to the current display, and is measured in µC (micro Coulomb) Average of actual charge delivered.

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4) Operating device in Neuromuscular Blocking Agent Monitoring Mode (NMS 450) Monitoring Neuromuscular Blocking Agents involves stimulating a neural pathway which facilitates the contracttion of an appendage. Based on the relative strength of contraction which is the result of a stimulus of specific intensity or waveform, it is possible to draw conclusions about the efficacy of an injected Neuromuscular Blocking Agent.

This mode is selected when the NMBA cable is inserted.

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