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Xavant Technology
Neuro Physiology

Organization of the Nervous System
Central Nervous System
Brains
Peripheral Nervous System
Sensory Division
Motor Division
Spinal Cord
Somatic Sensory
Visceral Sensory
Voluntary (Somatic)
Involuntary (Autonomic)
Sympathetic
Parasympathetic
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Neuro Physiology

Structure of a motor neuron
 Receptive (Input)
 Conducting
 Secretory (Output)
(Human Anatomy and Physiology – Marieb Third Edition 1995)
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Neuro Physiology

Membrane Potentials
Resting Potential = -70mV
(Human Anatomy and Physiology – Marieb Third Edition 1995)
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Neuro Physiology

Gated Channels
(Human Anatomy and Physiology – Marieb Third Edition 1995)
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Neuro Physiology

Action Potential – A all-or-none phenomenon
(Human Anatomy and Physiology – Marieb Third Edition 1995)
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Now with NMBA
Monitoring
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Xavant Technology
Nerve Stimulators

Where?
Nerve Stimulators can be used for
 Regional Anesthesia for various procedures using single shot
needles or stimulating catheters for post operative pain
management etc.
 Peripheral nerve blocks in trauma patients (Ambulances,
Emergency Room etc)
 Nerve Location in pain clinics
 Monitor the onset and reversal of muscle relaxants (NMBA
Monitoring)
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Nerve Stimulators

Why?
 60-80% increase in the success rate of peripheral nerve blocks
 Reduce time for performing nerve blocks (New Generation)
 Significantly reduce occurrence of nerve damage (New Generation)
 Avoid hematomas caused by multiple needle injections (Nerve
mapping)
 Less experience is needed for successful regional blocks
 Nerve mapping is a great educational tool for teaching purposes
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Nerve Stimulators

How?
Coulomb’s Law
Charge (C) = Current (A) x Time (s)
Total Charge (uC)
Current Amplitude (mA)
Pulse Width (ms)
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Nerve Stimulators

How?
Ohm’s Law
Voltage (V) = Current (A) x Resistance (Ω)
Normal Impedance
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Impedance too high
Nerve Stimulators

How?
 Nerve Mapping
 Nerve Locating
 NMBA Monitoring (NeuroMuscular Blocking Agent)
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STIMPOD NMS410

Features
 Display real-time feedback of the actual delivered
stimulus
 Proximity Indicator™ for near nerve functionality
 Single cable with auto-switching for nerve mapping and
nerve locating
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Xavant Technology
STIMPOD NMS410

Features
 Open circuit detection
 Non-linear mode allowing the user to customize current
and pulse width setting positions
 Set current adjustment intervals in 3 different current
ranges
 0.0 – 0.6 mA
 0.6 – 2.0 mA
 2.0 – 5.0 mA
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Xavant Technology
STIMPOD NMS450

Features
 NMBA Monitoring using 3 dimensional Accelerometer
 80mA current range
 Repeat timer for continuous monitoring
 Separate driving circuits for Locating and Mapping/NMBA
 Only 100V is generated for Locating mode
 400V is only generated for Mapping/NMBA mode
 + all the NMS410 features
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Xavant Technology
STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Train-of-Four (TOF)
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Train-of-Four (TOF)
• TOF ratio is the relation between the reaction to the 4th pulse compared to
the reaction to the 1st pulse i.e. 70%
• TOF count indicates the number of reactions if there is no 4th reaction i.e.
2/4
• A typical TOF ratio > 0.7 is required to indicate reversal
• Used during onset, maintenance and recovery until no fade is detected
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Double Burst (DB)
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Double Burst (DB)
• DB ratio is the relation between the reaction to the 2nd burst compared to
the reaction to the 1st burst i.e. 70%
• Used to detect residual paralysis
• Presence of fade indicates a residual neuromuscular blockade
• Could be followed by a clinical evaluation i.e. head lift for 5 seconds
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Post Tetanic Count (PTC)
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Post Tetanic Count (PTC)
• Use to assess intense block when there is no TOF count
• A response to PTC will be seen before any response to TOF
• The level of block is indicated by the number of counts compared to the
previous measurement i.e. 18 compared to 15 indicates a reversal
• If a count of 10 or higher is achieved it is indicative that the 1st response
on the TOF should appear soon
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Twitch (TWI)
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Twitch (TWI)
• Not a very sensitive measure for onset and reversal
• Usually used to test the placement of the electrodes
• No accelerometer feedback
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Xavant Technology
STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Tetanus (TET)
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STIMPOD NMS450

NMBA Monitoring Stimulation Mode
Tetanus (TET)
• Sustained response to this pattern corresponds with adequate reversal
• Is not very reliable
• Is very painful
• Should not be performed on the awake patient
• No accelerometer feedback
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Xavant Technology
STIMPOD NMS410/450

Components
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Xavant Technology
STIMPOD NMS410/450

Screen Diagnostics
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Xavant Technology
2009 Stimulator Market Summary
B. Braun HNS-12 – MARKET LEADER (for now)
75% Market Share (2009 Dollars)
$288,840 sold (2009)
66% Market Share (2009 Units)
339 units sold (2009)
ASP: $852 (2009)
Life-Tech EZStim II
22.5% Market Share (2009 Dollars)
$86,803 sold (2009)
30.7% Market Share (2009 Units)
157 units sold (2009)
ASP: $553 (2009)
Life-Tech Tracer III
2.5% Market Share (2009 Dollars)
$9,757 sold (2009)
2.9% Market Share (2009 Units)
15 units sold (2009)
ASP: $650
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B. Braun HNS-12 with SENSe
User Benefits:
• Now with SENSe technology for safer, easier, and
more efficient nerve stimulation
• Advanced ergonomic shape and large display
• Digital ratchet dial for precise tactile current
adjustment
• Quick access buttons allow direct switching of key
parameter values during procedure
• Alarm screens and acoustic signals inform the user of
any relevant deviations
• StimuPlex Remote Control allows sterile one-handed
operation
• StimuPlex Pen helps pre-assess the puncture site
• Study: “An objective assessment of nerve stimulators
for peripheral nerve blockade” – HNS-12 #1, but
StimPod not included
© Copyright 2010
Xavant Technology
STIMPOD NMS410/450

Comparison Study
BBRaun HNS12
STIMPOD NMS410
STIMPOD NMS450
Sterility
Offers a remote control covered
for use under sterile gloves
Unit can be covered by sterile
sheet
Unit can be covered by sterile
sheet
Device attachment
No attachment mechanism
Special clip allows for
attachment to drapes
Special clip allows for attachment
to drapes
Current Range
Nerve Locating 0.0 – 5.0 mA
Nerve Mapping 0.0 – 5.0 mA
NMBA Monitoring None
Nerve Locating 0.0 – 5.0 mA
Nerve mapping 0 – 20 mA
NMBA Monitoring None
Nerve Locating
0.0 – 5.0 mA
Nerve Mapping
0 – 20 mA
NMBA Monitoring 0 – 80 mA
Pulse Width
0.05ms, 0.1ms, 0.3ms, 0.5ms,
1ms
0.05ms, 0.1ms, 0.3ms, 0.5ms,
1ms
0.05ms, 0.1ms, 0.3ms, 0.5ms,
1ms
Nerve Mapping
Yes - 5mA maximum current
Yes - 20mA maximum current
Yes - 20mA maximum current
Auto Sensing
Technology
No
Yes
Combination Cable Auto Sensing
Yes
Combination cable Auto Sensing
Show Current
Delivered
Yes
Yes – Actual waveform delivered
showing exact charge
Yes – Actual waveform delivered
showing exact charge
NMBA Monitoring
No
No
Yes - 3 dimensional accelerometer
© Copyright 2010
Xavant Technology
B. Braun HNS-12 with SENSe
What is SENSe?
The SENSe technology
(Sequential Electrical
Nerve Stimulation) is a
sequence of two fixed
impulse durations of 0.1
ms along with a third
longer impulse duration.
This results in getting the
first muscle twitch already
at a distance from the
nerve and requires less
adjustments to the
amperage control, while
maintaining the visual
feedback.
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Life-Tech EZstim II
User Benefits:
• Large, bright, easily read LCD continuously displays
all instrument settings and battery status.
• eShield protects agains electromagnetic interference.
Unique interference protection capability eliminates
need to disconnect the stimulator from the patient
during electro-surgery procedures
• Audible and visual warning of any open circuit or high
resistance condition
• Detachable lead sets allow quick and easy
replacement of patient leads
•Function-specific electrode connectors guard against
inappropriate use of stimulator
• Large, high-sensitivity control knob facilitates precise
current adjustment
• Pause mode allows changing stimulus parameters
without stimulating
• Optional protective boot and IV pole mount
Source: Life-Tech EZstim II Brochure
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Life-Tech EZstim II
User Benefits:
• Neuromuscular Block Monitor Function:
Complete selection of stimulus patterns – twitch,
train of four, double burst, or tetanus
• Nerve Block Function: Audible “chirp” pulse
amplitude indicator frees operator from having to
watch the display
• Optional SoloStim foot control allows handsfree operation in nerve locator mode
• Dual current range (1.5 or 5 mA) with SoloStim
provides a wide range when distant from nerve,
and fine control when close to nerve
Source: Life-Tech EZstim II Brochure
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Life-Tech Tracer III
User Benefits:
• Large, bright, easily read LCD continuously displays all
instrument settings and battery status.
• Pause mode allows changing stimulus parameters
without stimulating
• Audible “chirp” indicator of pulse delivery and
amplitude frees the operator from having to watch the
display
• Chirp volume is adjustable to be optimal for any
environment
• Adjustable pulse width allows selective stimulation of
motor or sensory fibers
• Both audible and visual warnings indicate any
discrepancy between actual current and selected
current
• Large, high sensitivity current control knob
• Detachable lead set allows quick and easy
replacement of patient leads
Source: Life-Tech Tracer III Brochure
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Life-Tech Tracer III
User Benefits:
• SoloStim Foot Control
• Dual current range (1.5/5.0 mA) provides
wide range when distant from nerve and
narrow range with finer control when close
to nerve
• Hands-free operation increases the ease,
rapidity and accuracy of current adjustment
and in many facilities eliminates the need
for an assistant
Source: Life-Tech EZstim II Brochure
© Copyright 2010
Xavant Technology
STIMPOD NMS410/450

Comparison Study
LifeTech EzStim II
STIMPOD NMS410
STIMPOD NMS450
Sterility
None
Unit can be covered by sterile
sheet
Unit can be covered by sterile
sheet
Device attachment
IV Pole Attachment
Special clip allows for
attachment to drapes
Special clip allows for attachment
to drapes
Current Range
Nerve Locating 0.05 – 5.00 mA
Nerve Locating 0.0 – 5.0 mA
Nerve mapping 0 – 20 mA
NMBA Monitoring None
Nerve Locating
0.0 – 5.0 mA
Nerve Mapping
0 – 20 mA
NMBA Monitoring 0 – 80 mA
No Nerve Mapping
NMBA Monitor 0 – 80 mA
Pulse Width
0.1ms, 0.2ms
0.05ms, 0.1ms, 0.3ms, 0.5ms,
1ms
0.05ms, 0.1ms, 0.3ms, 0.5ms,
1ms
Nerve Mapping
No
Yes 20mA maximum current
Yes 20mA maximum current
Auto Sensing
Technology
No
Yes
Combination Cable Auto
Sensing
Yes
Combination cable Auto Sensing
Show Current
Delivered
No
Yes – Actual waveform delivered
showing exact charge
Yes – Actual waveform delivered
showing exact charge
NMBA Monitoring
Yes - No Accelerometer
No
Yes - 3 dimensional accelerometer
© Copyright 2010
Xavant Technology
Pajunk MultiStim SWITCH
User Benefits:
• Large, clearly arranged display
• Analogous setting of the intensity of
the stimulation current by means of a
notched turning-knob
• Integrated safety features
• High-precision, microprocessorcontrolled adjustment of constant
current
• Added continuous indication of the
patient resistance by means of two
analogous bar graphs
• Switch over key switches stimulation
from needle to catheter
Source: www.PAJUNK.com
Pajunk MultiStim SWITCH
User Benefits:
• Switch over key switches stimulation from
needle to catheter
• Stimulation by cannula
• cannula symbol appears on the
display
• maximum stimulation current intensity
will be 6 mA
• Stimulation by catheter
• the word “CATH” will appear on the
display
• range of stimulation current intensity
will be increased to 20 mA
• correspond with the specific
requirements of epidural stimulation
Source: www.PAJUNK.com
Pajunk MultiStim SENSOR
User Benefits:
• When using the PEG-electrode, the nerve is
stimulated through the skin
• Will evoke a reflexive response when the
nerve is encountered
• The cannula is introduced at the insertion
point identified by means of this method
• The stimulation current is switched over to
the cannula by keystroke
• Pressing the PEG- or Cannula button will
cause the stimulation to be switched to the
handle or the cannula, as may be required
• The intensity and the frequency of the
stimulation current, as well as the pulse width
can be adjusted separately for both outputs
• The stimulation pulse width can be adjusted
fast and simple with a button of its own in a
number of steps
Source: www.PAJUNK.com
Pajunk MultiStim VARIO/ MultiStim PLEX
User Benefits:
• Used for nerve stimulation for the
identification of peripheral nerves, as
well as the percutaneous stimulation of
neuromuscular monitoring in general
anesthesia
• Operation with one hand and audio
visual signals with adjustable volume
allow a full concentration on the patient
• All required stimulation impulse
patterns and frequencies are recallable
• The bandwidth of the stimulation
impulse is adjustable step by step, from
0.1 to 1.0 ms.
• Available constant current region 0-60
mA, adjustable in 0.1 mA steps
•The Pause function facilitates the
change of the stimulation parameters
without impulse output
MultiStim Plex
The MultiStim PLEX is very easy to handle.
The nerve stimulator is used in the plexus
anaesthesia particularly for training
purposes. In comparison with the MultiStim
VARIO, MultiStim PLEX has no function for
the percutaneous relaxation monitoring and
no PAUSE-function. The bandwidth of the
stimulation impulse are defined with 0,1ms.
The constant current field is between 0 - 6
mA, adjustable in 0,01 mA steps.
Source: www.PAJUNK.com
STIMPOD NMS410/450

Comparison Study
Pajunk MultiStim Vario
STIMPOD NMS410
STIMPOD NMS450
Sterility
None
Unit can be covered by sterile
sheet
Unit can be covered by sterile
sheet
Device attachment
No attachment mechanism
Special clip allows for
attachment to drapes
Special clip allows for attachment
to drapes
Current Range
Nerve Locating 0.0 – 5.0 mA
Nerve Mapping 0 – 60 mA*
NMBA Monitoring 0 – 60 mA
Nerve Locating 0.0 – 5.0 mA
Nerve mapping 0 – 20 mA
NMBA Monitoring None
Nerve Locating
0.0 – 5.0 mA
Nerve Mapping
0 – 20 mA
NMBA Monitoring 0 – 80 mA
Pulse Width
0.1ms, 0.3ms, 0.5ms, 1ms
0.05ms, 0.1ms, 0.3ms, 0.5ms,
1ms
0.05ms, 0.1ms, 0.3ms, 0.5ms,
1ms
Nerve Mapping
Yes – Need “Switchbox”
60mA maximum current
Yes - 20mA maximum current
Yes - 20mA maximum current
Auto Sensing
Technology
No
Yes
Combination Cable Auto
Sensing
Yes
Combination cable Auto Sensing
Show Current
Delivered
Yes
Yes – Actual waveform delivered
showing exact charge
Yes – Actual waveform delivered
showing exact charge
NMBA Monitoring
Yes - No Accelerometer
No
Yes - 3 dimensional accelerometer
* Need Switchbox
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Xavant Technology
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