Activa® RC and Activa PC

Activa® RC and Activa PC
M927893A_fc.fm 8/21/08
3:23 pm
Activa® RC and Activa PC
Multi-program neurostimulators
Information for prescribers
c Rx only
0123
M927893A002
M927893A_fc.fm 8/21/08
3:23 pm
Medtronic®, Activa®, Itrel®, and Soletra® are registered trademarks of Medtronic, Inc.
M927893A002
M927893ATOC.fm
8/21/08
3:23 pm
Table of contents
Contraindications 3
Warnings 3
Precautions 5
Physician training 5
Storage and sterilization 6
System implant 6
Clinician programming 8
Patient programming and patient control devices 9
Charging system 9
Patient activities 10
Component disposal 10
Patient selection (Activa RC only) 11
Clinical studies and adverse events 12
Adverse events summary 12
Patient counseling information 13
Appendix A: Electromagnetic interference 15
Hospital or medical environment 15
Home or occupational environment 16
Refer to the indications sheet for indications and related information.
Refer to the device implant manual for device description, package
contents, device specifications, and instructions for use.
Refer to System Eligibility, Battery Longevity, Specifications reference
manual packaged with the software application card for neurostimulator
selection, battery longevity calculations and specific neurostimulator
specifications.
c Refer to the clinical summary booklet packaged with the
neurostimulator for information on the clinical study results of the
neurostimulation system and individualization of treatment.
Information for prescribers
M927893A002
2007-09
English 1
M927893ATOC.fm
2 English
M927893A002
8/21/08
3:23 pm
Information for prescribers
2007-09
M927893A_ch.fm 8/21/08
3:23 pm
Contraindications
Implantation of an Activa RC or Activa PC Brain Stimulation System is contraindicated for:
■
Patients exposed to diathermy. Do not use shortwave diathermy, microwave diathermy
or therapeutic ultrasound diathermy (all now referred to as diathermy) on patients
implanted with a neurostimulation system. Energy from diathermy can be transferred
through the implanted system and can cause tissue damage at the location of the
implanted electrodes, resulting in severe injury or death.
Diathermy can also damage the neurostimulation system components, resulting in loss
of therapy and requiring additional surgery for system explantation and replacement.
Advise your patient to inform all their health care professionals that they should not be
exposed to diathermy treatment.
Injury to the patient or damage to the device can occur during diathermy treatment
when:
– the neurostimulation system is turned ON or OFF.
– diathermy is used anywhere on the body - not just at the location of the
neurostimulation system.
– diathermy delivers heat or no heat.
– any component of the neurostimulation system (lead, extension, neurostimulator)
remains in the body.
■
Patients who will be exposed to Magnetic Resonance Imaging (MRI) using a full body
transmit radio-frequency (RF) coil, a receive-only head coil, or a head transmit coil that
extends over the chest area. Performing MRI with this equipment can cause tissue
lesions from component heating, especially at the lead electrodes, resulting in serious
and permanent injury including coma, paralysis or death. Refer to the MRI guidelines
manual packaged with this product for comprehensive safety information and
instructions.
■
Patients for whom test stimulation is unsuccessful.
■
Patients who are unable to properly operate the Activa PC Brain Stimulation System,
which includes a patient programmer, or the Activa RC Brain Stimulation System, which
includes a patient programmer and a charging system.
Warnings
Avoid excessive stimulation – There is a potential risk of brain tissue damage for
stimulation parameter settings of high amplitudes and wide pulse widths.
The Activa System is capable of parameter settings outside the range of those used in the
clinical studies. Stimulation parameter ranges for symptom suppression are typically within
1 to 3.5 V for amplitude, 60 to 120 µsec for pulse width, and 130 to 185 Hz for rate. Higher
amplitude and pulse width may indicate a system problem or less than optimal lead
placement. Parameter values exceeding the recommended output settings should only be
programmed with due consideration of the warnings concerning charge densities described
in the programming guide.
Information for prescribers
M927893A002
2007-09
English 3
M927893A_ch.fm 8/21/08
3:23 pm
If programming of stimulation parameters exceeds charge density limits, the following
programmer warning appears: WARNING: CHARGE DENSITY MAY BE HIGH ENOUGH
TO CAUSE TISSUE DAMAGE.
The use of rates less than 30 Hz may “drive” tremor, ie, cause it to occur at the same
frequency as the programmed frequency. For this reason, rates should not be programmed
below 30 Hz.
Case damage – If the neurostimulator case is ruptured or pierced due to outside forces,
severe burns could result from exposure to the battery chemicals.
Coagulopathies – Use extreme care with lead implantation in patients with a heightened
risk of intracranial hemorrhage. Physicians should consider underlying factors, such as
previous neurological injury, or prescribed medications (anticoagulants), that may
predispose a patient to the risk of bleeding.
Electromagnetic interference (EMI) – Electromagnetic interference is a field of energy
generated by equipment found in the home, work, medical or public environments that is
strong enough to interfere with neurostimulator function. Neurostimulators include features
that provide protection from electromagnetic interference. Most electrical devices and
magnets encountered in a normal day are unlikely to affect the operation of a
neurostimulator. However, sources of strong electromagnetic interference can result in the
following effects:
■
Serious patient injury or death - it is possible for the extension, lead, or both to “pick
up” electromagnetic interference and deliver an excess voltage, which can in turn
deliver an excessive amount of heat to the brain.
■
System damage - resulting in a loss of or change in symptom control and requiring
surgical replacement.
■
Operational changes to the neurostimulator - causing it to turn on or off, or to reset
to power-on-reset (POR) settings, resulting in loss of stimulation, return of symptoms,
and in the case of POR, requiring reprogramming by a clinician.
■
Unexpected changes in stimulation - causing a momentary increase in stimulation
or intermittent stimulation, which some patients have described as a jolting or shocking
sensation.
Refer to “Appendix A: Electromagnetic interference” on page 15 for guidelines on the
interaction of electromagnetic interference and an implanted Activa RC or Activa PC
System.
Importance of regular recharging (Activa RC only) – Inform patients and their
caregivers of the importance of maintaining a regular schedule of recharging.
Magnetic Resonance Imaging – Do not conduct an MRI examination on a patient with any
implanted Activa System component until you read and fully understand all MRI information
in this manual and the safety information and instructions in the MRI guidelines manual
packaged with this product. Do not conduct an MRI examination at parameters other than
those described in these guidelines. Failure to follow all warnings and guidelines related to
MRI can result in serious and permanent injury including coma, paralysis, or death.
Placement of lead-extension connector in neck – Do not place the lead-extension
connector in the soft tissues of the neck. Placement in this location has been associated with
an increased incidence of lead fracture.
4 English
M927893A002
Information for prescribers
2007-09
M927893A_ch.fm 8/21/08
3:23 pm
Replacement Procedure – Do not replace two Soletra Model 7426 Neurostimulators with
one bilateral neurostimulator unless retunneling is performed so both lead-extensions are
on the same side of the body. Otherwise, the “looped” configuration formed by the leadextensions increases the potential for electromagnetic interference (EMI) effects.
Return of symptoms and rebound effect – Inform patients and their caregivers that
abrupt cessation of stimulation for any reason, including failure to maintain adequate battery
charge in rechargeable neurostimulators, will probably cause a return of disease symptoms.
In some cases, symptoms may return with intensity greater than was experienced prior to
system implant (rebound effect). This can in rare cases constitute a medical emergency.
For patients with rechargeable neurostimulators, it is important that the clinician emphasize
the following:
■
Patients must willing and able to perform battery status checks and battery recharge
activities on a frequent basis.
■
The device charge level should be maintained such that symptoms are controlled.
■
The recharge warnings from the patient programmer must be understood and heeded
by the patient and caregiver.
■
Medication may aid in symptom control during short periods of time following depletion
of the device before a recharge session.
If symptoms worsen or do not abate following recharge, the patient should contact his or her
clinician immediately so the status of the system can be assessed and the condition of the
patient can be monitored.
Theft Detectors and Screening Devices – Theft detectors found in retail stores, public
libraries, etc., and airport/security screening devices may cause the stimulation power
source of an implantable neurostimulation system to switch Off It is also possible that
sensitive patients, or those with low stimulation thresholds, may experience a momentary
increase in their perceived stimulation. For other indications, higher levels of stimulation
have been described as uncomfortable (“jolting” or “shocking”) by some patients as they
pass through these devices. Refer to “Appendix A: Electromagnetic interference” for more
information.
Precautions
Physician training
Prescribing physicians should be experienced in the diagnosis and treatment of movement
disorders and should be familiar with the use of the Activa System. Implanting physicians
should have expertise with functional stereotactic neurosurgical treatment of movement
disorders. Such expertise should include knowledge of the anatomical and
neurophysiological characteristics of the targeted nucleus, surgical and /or implantation
techniques for the Activa System, operational and functional characteristics of the Activa
System, and experience in the continued management of patients by stimulation parameter
adjustment. Physicians may contact Medtronic before prescribing or implanting an Activa
System for the first time and request a referral to a physician experienced in the use of Activa
Therapy. Prescribing and implanting physicians of Activa RC systems should be aware of
the patient requirements for a rechargeable neurostimulation system.
Information for prescribers
M927893A002
2007-09
English 5
M927893A_ch.fm 8/21/08
3:23 pm
All Activa System programming should be by or under the supervision of a physician or other
experienced medical personnel familiar with the use of the programming software and
equipment. Physicians should be thoroughly familiar with Activa System supporting
material, including all product labeling and education and training materials.
Storage and sterilization
Component packaging – Do not implant a component if the following circumstances have
occurred:
■
The storage package has been pierced or altered because component sterility cannot
be guaranteed and infection may occur.
■
The component shows signs of damage because the component may not function
properly.
■
The use-by date has expired because component sterility cannot be guaranteed and
infection may occur; also, neurostimulator battery longevity may be reduced and may
require early replacement.
Sterilization – Medtronic has sterilized the package contents according to the process
indicated on the package label before shipment. This device is for single use only and is not
intended to be resterilized.
Storage temperature: leads and extensions – Do not store or transport the leads or
extensions above 57°C (135°F) or below -34°C (-30°F). Temperatures outside this range
can damage components.
Storage temperature: neurostimulators – Do not store or transport the neurostimulator
above 52°C (125°F) or below -18°C (0°F). Temperatures outside this range can damage
components.
System implant
Battery longevity and brain target selection – Stimulation settings for systems
implanted in the internal Globus Pallidus (GPi) may be higher than stimulation settings for
systems implanted in the Subthalmic Nucleus (STN). Consequently, when implanted in the
Gpi, rechargeable systems may need to be charged more frequently and nonrechargeable
systems may have reduced battery longevity compared to systems implanted in the STN.
Compatibility, all components – Follow these guidelines when selecting system
components:
■
Medtronic components: For proper therapy, use only Medtronic Neurological
components that are compatible or specified in an intended use statement (if present).
Components are compatible when the following conditions are met:
– Components have the same indication.
– For implanted components, the contact spacing and the number of electrode
contacts at the connections for the lead and extension/neurostimulator or extension
and neurostimulator are the same.
For each product, refer to the indication insert(s) and shipping label artwork for this
information.
6 English
M927893A002
Information for prescribers
2007-09
M927893A_ch.fm 8/21/08
3:23 pm
Non-Medtronic components: No claims of safety or efficacy are made with regard to the
compatibility of using non-Medtronic components with Medtronic components. Refer to
the non-Medtronic documentation for information.
Components – The use of non-Medtronic components with this system may result in
damage to Medtronic components, loss of stimulation or patient injury.
Component failures – The Activa System may unexpectedly cease to function due to
certain events. These events, which can include electrical short or open circuits, conductor
(wire) fracture, and insulation breaches, cannot be predicted. The patient's disease
symptoms will return if the device ceases to function.
Component handling – Handle the implantable components of this system with extreme
care. These components may be damaged by excessive traction or sharp instruments,
which may result in intermittent or loss of stimulation, requiring surgical replacement.
Refer to the appropriate implant manual for additional instructions.
Extension routing for multiple leads – When multiple leads are implanted, route the
lead-extensions so the area between them is minimized (Figure 1). If the lead-extensions
are routed in a loop, the loop will increase the potential for electromagnetic interference
(EMI).
■
3URSHU
,PSURSHU
Figure 1. Routing for multiple lead-extensions.
Lead materials – The polyurethane tubing of the lead may release neurotoxic or
carcinogenic compounds. Data are insufficient to assess the likelihood of these effects
occurring in patients who receive the device.
Long-term safety and effectiveness of Activa Therapy – The long-term safety and
effectiveness of Activa Therapy has not been established.
Multiple implants – The long-term safety associated with leads left in place without use,
replacement of leads, multiple implants into the target structure, and lead explant is
unknown.
Information for prescribers
M927893A002
2007-09
English 7
M927893A_ch.fm 8/21/08
3:23 pm
Neurostimulator location – Select a location that is:
■
a minimum of 20 cm (8 in) away from another neurostimulator to minimize telemetry
interference and possible inappropriate therapy.
■
on the opposite side of the body from another active implanted device (eg, pacemaker,
defibrillator) to minimize possible interaction between the devices.
■
away from bony structures (eg, 3 – 4 cm [1.2 – 1.6 in]) to minimize discomfort at the
neurostimulator site.
■
away from areas of restriction or pressure to minimize the potential for skin erosion and
patient discomfort.
■
in an area accessible to the patient for proper neurostimulator recharging (Activa RC
only) and proper operation of a patient control device.
Neurostimulator location and MRI – If MRI is planned, avoid, if possible, implanting the
neurostimulator in the abdomen. This requires the use of a longer length lead/extension
system that can increase the heating from MRI induced RF currents, especially at the lead
electrodes. Refer to the MRI guidelines for comprehensive safety information and
instructions.
Clinician programming
Effects on other medical devices – The Activa System may affect the operation of other
implanted devices, such as cardiac pacemakers and implantable defibrillators. Possible
effects include sensing problems and inappropriate device responses. If the patient requires
concurrent implantable pacemaker and/or defibrillator therapy, careful programming of each
system may be necessary to optimize the patient's benefit from each device.
Parameter adjustment – To prevent possible unpleasant stimulation decrease the
amplitude(s) to 0.0 V before:
■
connecting or disconnecting the cable to the screener or external neurostimulator.
■
replacing the external neurostimulator or screener batteries.
Programmer interaction with a cochlear implant – When the patient has a cochlear
implant, minimize or eliminate the potential for unintended audible clicks during telemetry by
keeping the external portion of the cochlear system as far from the programming head as
possible or by turning OFF the cochlear implant during programming.
Programmer interaction with flammable atmospheres – The programmer is not
certified for use in the presence of a flammable anaesthetic mixture with air or with oxygen
or nitrous oxide. The consequences of using the programmer near flammable atmospheres
are unknown.
Programmer interaction with other active implanted devices – When a patient has a
neurostimulator and another active implanted device (eg, pacemaker, defibrillator,
neurostimulator), the radio-frequency (RF) signal used to program these devices may reset
or reprogram the other device. To verify that inadvertent programming did not occur,
clinicians familiar with each device should check the programmed parameters of each
device before the patient is discharged from the hospital and after each programming
session of either device (or as soon as possible after these times).
Also, inform patients to contact their physician immediately if they experience symptoms that
could be related to either device or to the medical condition treated by either device.
8 English
M927893A002
Information for prescribers
2007-09
M927893A_ch.fm 8/21/08
3:23 pm
Screening with external neurostimulators – When screening a patient who has multiple
leads implanted, do not operate multiple external neurostimulators simultaneously. The
signals from simultaneously operated external neurostimulators can interfere with each
other and result in incorrect results.
Telemetry signal disruption from EMI – Do not attempt telemetry near equipment that
may generate electromagnetic interference (EMI). If EMI disrupts programming, move the
programmer away from the likely source of EMI. Examples of sources of EMI are magnetic
resonance imaging (MRI), lithotripsy, computer monitors, cellular telephones, motorized
wheelchairs, x-ray equipment, and other monitoring equipment. Interrupting telemetry can
result in incorrect or incomplete programming.
Test stimulation – An intraoperative test stimulation phase during the lead implant
procedure verifies a correct lead placement that results in symptom suppression with
minimal side effects. Perform test stimulation intraoperatively. If there is no symptom
suppression, do not implant the Activa System.
Patient programming and patient control devices
Group selection – Patients should select the group recommended by the clinician for the
desired therapeutic effect. Use of another group may result in unpleasant stimulation when
stimulation is turned ON.
Patient control devices may affect other implanted devices – Do not place the patient
control device (ie, patient programmer) over another active implanted medical device (eg,
pacemaker, defibrillator, another neurostimulator). The patient control device could
unintentionally change the operation of the other device.
Patient device handling – To avoid damaging the device, do not immerse it in liquid; do not
clean it with bleach, nail polish remover, mineral oil, or similar substances; and do not drop
it or mishandle it in a way that may damage it.
Patient device use – When operating a patient programmer or charging system, use
special care near flammable or explosive atmospheres. An interaction between the
flammable or explosive atmospheres and the battery in the device could occur. The
consequences of using a battery-powered device near flammable or explosive atmospheres
are unknown.
Charging system
Low battery charge level (Activa RC only) – Advise patients to charge the
neurostimulator on a regular basis, taking into consideration the therapeutic parameters and
battery usage of the patient, to prevent the battery from overdischarging. If the
neurostimulator battery is allowed to overdischarge, the patient cannot charge the
neurostimulator; however, the clinician may be able to restore the battery function using the
Physician Recharge Mode on the recharger (refer to the troubleshooting section of the
software manual).
Allowing the neurostimulator battery to overdischarge will permanently affect the
neurostimulator in one of the following ways:
■
Battery function is restored; however, charging sessions may be more frequent
because battery capacity has been reduced.
Information for prescribers
M927893A002
2007-09
English 9
M927893A_ch.fm 8/21/08
3:23 pm
Battery function is not restored and the neurostimulator must be surgically replaced.
Battery function is not restored when:
– the neurostimulator battery is permanently damaged.
– the neurostimulator battery has been overdischarged and restored twice before. The
third time the battery is overdischarged, the neurostimulator will reach end of
service. Surgery is required to replace the neurostimulator.
Wound contact (Activa RC only) – DO NOT use the recharger on an unhealed wound.
The recharger, recharger antenna, and holster are not sterile, and contact with the wound
may cause an infection.
■
Patient activities
Component manipulation by patient – Advise your patient to avoid manipulating the
implanted system components (eg, the neurostimulator, the burr hole site). This can result
in component damage.
Patient activities/environmental precautions – Patients should exercise reasonable
caution in avoidance of devices which generate a strong electric or magnetic field. Close
proximity to high levels of electromagnetic interference (EMI) may cause a neurostimulator
to switch On or Off. The system also may unexpectedly cease to function. For these
reasons, the patient should be advised about any activities that would be potentially unsafe
if their symptoms unexpectedly return. For additional information about devices which
generate electromagnetic interference, call Medtronic at 1-800-707-0933.
Component disposal
When explanting a device (eg, replacement, cessation of therapy, or postmortem), or when
disposing of accessories, follow these guidelines:
■
If possible, return the explanted device with completed paperwork to Medtronic for
analysis and disposal. Refer to the back cover for the mailing addresses.
■
To allow for device analysis, do not autoclave the device or expose the device to
ultrasonic cleaners.
■
Dispose of any unreturned components according to local environmental regulations;
in some countries, explanting a battery-powered implantable device is mandatory.
– Do not incinerate or cremate the neurostimulator because it may explode if
subjected to these temperatures.
– Do not reuse any implantable device or implantable accessory after exposure to
body tissues or fluids because the functionality of the component cannot be
guaranteed.
10
English
M927893A002
Information for prescribers
2007-09
M927893A_ch.fm 8/21/08
3:23 pm
Patient selection (Activa RC only)
Consultation with the neurologist who will provide follow-up care is recommended prior to
patient selection.
Compliance with checking the battery status regularly is critical. Medtronic recommends a
practice period for the patient and associated caregiver prior to implant, to assess whether
the patient will be willing and able to incorporate the required recharging activities into
current activities of daily living.
Selection of patients living in assisted care or nursing home facilities is not recommended,
as maintenance of therapy maybe relegated to the care staff who may not be adequately
trained to assist with recharge activities.
Careful consideration should be exercised when determining if a patient is appropriate for a
rechargeable Activa RC Neurostimulator. The following should be considered for the
expected duration of the implant period:
■
Patient’s ability to use the patient programmer and correctly interpret the icons that
appear on the screen
■
Patient's ability to regularly monitor the status of the rechargeable battery and respond
appropriately
■
Patient’s ability to accurately locate their implanted neurostimulator, properly position
the recharge antenna for sufficient coupling, put on the recharge holster/belt, and
monitor progress during the recharge session
■
Patient's ability to perform charging activities for sufficient duration and frequency to
maintain therapy and to perform charging activities on an ongoing basis
Special consideration should be given to:
■
Available level of support from a care giver, to assist the patient with monitoring and
recharging activities
■
Expected effect from cessation of therapy, should patient fail to recharge on schedule
or when alerted
■
Patient's age, as very young or very old patients may have difficulty performing required
monitoring and recharging of the device
■
Patient's mental capacity, as patients with cognitive impairment or those prone to
developing dementia would likely have difficulty performing device-related tasks
without assistance
■
Patient’s physical ability, as patients with higher degrees of motor impairment might
have difficulty with the physical requirements of monitoring and recharging the device
■
Patient’s visual ability, the patient needs to be able to read the patient programmer or
recharger display screen to assess battery status
■
Patient’s willingness to use the patient programmer alert or a different method that will
be effective in reminding the patient to check the battery status on a regular basis
■
Patient’s (and caregiver’s) willingness to continue recharging activities as necessary
under all circumstances, eg, power outages, travel, and hospitalizations, and recognize
the critical nature of maintaining a charged battery in the neurostimulator
Information for prescribers
M927893A002
2007-09
English
11
M927893A_ch.fm 8/21/08
3:23 pm
Clinical studies and adverse events
The clinical use of implantable deep brain stimulation systems for Parkinson’s disease and
essential tremor is supported by the Medtronic Parkinson’s disease clinical studies using the
Itrel II Model 7424 Neurostimulator.
Because safety and effectiveness of the Activa Parkinson’s Control therapy was established
using bilateral Itrel II neurostimulators, clinical results and adverse event rates associated
with other implantable deep brain stimulation systems for Parkinson’s disease and essential
tremor may not be identical. Refer to the system components sheet packaged with the DBS
Lead for more information about specific Activa System components.
Adverse events summary
Deep brain stimulation may potentially have the following adverse events:
■
Allergic or immune system response to the implanted materials
■
Infection
■
Lead, extension, or neurostimulator erosion through the skin or migration
■
Persistent pain at the neurostimulator site
■
Seroma or hematoma at the neurostimulator site
■
Intracranial hemorrhage, immediate or delayed, which could result in temporary or
permanent muscle weakness, paralysis, aphasia, or death.
■
Lead and extension fracture
■
Loss of therapeutic effect
■
Mentation impairment such as attention or cognitive deficits, memory disturbances,
confusion, or psychiatric disturbances
■
Motor problems such as paresis, weakness, incoordination, muscle spasms, gait
disorders, tremor, dystonia, or chorea
■
Seizures
■
Sensory changes
■
Speech problems such as dysphasia or dysarthria
■
Undesirable sensations such as paresthesia that could be either temporary or
permanent
■
Visual disturbances, such as diplopia, oculomotor difficulties or other visual field effects
c For a comprehensive summary of adverse events, refer to the Clinical Summary.
12
English
M927893A002
Information for prescribers
2007-09
M927893A_ch.fm 8/21/08
3:23 pm
Patient counseling information
Before surgery, the patient and family should be advised of the known risks of the surgical
procedure and the therapy, as well as the potential benefits. After the Activa System is
implanted, the patient should also be advised to read the patient manual included in the
neurostimulator package.
Physicians should provide patients with information about:
■
the components of the neurostimulation system: lead, extension, and neurostimulator.
■
instructions for using the neurostimulation system, including the patient programmer
and charging system (Activa RC).
■
the indications, contraindications, warnings, and precautions for a neurostimulation
system.
Physicians should also instruct patients to:
■
always inform any healthcare personnel that they have an implanted neurostimulation
system before any procedure is begun.
■
contact their physician if they notice any unusual symptoms or signs.
Information for prescribers
M927893A002
2007-09
English
13
M927893A_ch.fm 8/21/08
14
English
M927893A002
3:23 pm
Information for prescribers
2007-09
M927893A_appA.fm 8/21/08
3:23 pm
Appendix A: Electromagnetic interference
Electromagnetic interference is a field (electrical, magnetic or a combination of both) that is
generated by various medical or environmental devices. These medical and environmental
(home, occupational, and other) devices may generate enough interference to change the
parameters of a neurostimulator: turn a neurostimulator off and on, or cause a
neurostimulator to surge, shock, or jolt the patient.
In addition, it is possible for the extension, lead, or both to “pick up” electromagnetic
interference and deliver an excess voltage, which can in turn deliver an excessive amount
of heat to the brain. Refer to the sections that follow for guidelines on the interaction of
electromagnetic interference and an implanted Activa System.
Activa neurostimulators are designed to assure immunity from most common sources of
electromagnetic interference (EMI). Because many different types of EMI sources exist, it is
impossible to specify all interference sources here. However, the most common sources of
EMI are discussed below.
Severe electromagnetic fields, such as those that exist near electrocautery equipment, can
reprogram a neurostimulator, temporarily suppress the output of a neurostimulator, and
cause damage to the implanted system components.
Hospital or medical environment
Before any medical procedure is begun, patients should always inform any health care
personnel that they have an implanted neurostimulation system. The potential for the
following effects results from an interaction of the neurostimulation system and equipment—
even when both are working properly.
Most routine diagnostic procedures, such as fluoroscopy and x-rays, are not expected to
affect system operation. However, because of higher energy levels, sources such as
transmitting antennas found on various diagnostic and therapeutic equipment may interfere
with the Activa System.
Electrocautery – Electrocautery can damage the lead, the extension, or both. It can also
cause temporary suppression of neurostimulator output and/or reprogramming of the
neurostimulator. If use of electrocautery is necessary, the current path (ground plate) should
be kept as far away from the neurostimulator, extension, and lead as possible, and use of
bipolar electrocautery is recommended.
External defibrillators – If a patient requires external defibrillation, the first consideration
should be patient survival. Safety for use of external defibrillatory discharges on patients
with neurostimulation systems has not been established. External defibrillation may damage
a neurostimulator.
If external defibrillation is necessary, follow these precautions to minimize current flowing
through the neurostimulator and lead system:
■
Position defibrillation paddles as far from the neurostimulator as possible.
■
Position defibrillation paddles perpendicular to the implanted neurostimulator-lead
system.
■
Use the lowest clinically appropriate energy output (J [watt seconds]).
■
Confirm neurostimulation system function following any external defibrillation.
Information for prescribers
M927893A002
2007-09
English
15
M927893A_appA.fm 8/21/08
3:23 pm
High radiation sources – High radiation sources, such as cobalt 60 or gamma radiation,
should not be directed at the neurostimulator. If a patient requires radiation therapy in the
vicinity of the neurostimulator, place lead shielding over the device to prevent radiation
damage.
Lithotripsy – Use of high output ultrasonic devices, such as an electrohydraulic lithotriptor,
is not recommended for patients with an implanted neurostimulation system. While there is
no danger to the patient, exposure to high output ultrasonic frequencies may result in
damage to the neurostimulator circuitry. If lithotripsy must be used, do not focus the beam
near the neurostimulator.
Psychotherapeutic procedures – The safety of psychotherapeutic procedures using
equipment that generates electromagnetic interference (eg, electroshock therapy,
transcranial magnetic stimulation) has not been established.
Home or occupational environment
Activa neurostimulators should not be affected by normal operation of electrical equipment
such as household appliances, electric machine shop tools, microwave ovens, RF
transmitting systems, or microwave frequency transmitting systems. A strong magnetic field
(electromagnet or permanent magnet) can switch the neurostimulator output from On to Off
or Off to On, but does not change the programmed parameters.
Advise your patients to avoid or to exercise care when approaching the following:
■
Theft detectors
■
Airport/security screening devices
■
Large stereo speakers with magnets
■
Electric arc welding equipment
■
Electric steel furnaces
■
Electric induction heaters (used in industry to bend plastic)
■
Power lines
■
Electric substations and power generators
If your patient suspects an electrical device or magnet is interfering with the neurostimulator,
advise him/her to move away from it, or turn the device off. Then, the patient can use the
patient programmer to set the neurostimulator back to the desired On or Off state. When
switched On, the neurostimulator will resume stimulation at the previously programmed
level.
Home appliances – Home appliances that are in good working order and properly
grounded do not usually produce enough electromagnetic interference (EMI) to interfere
with neurostimulator operation. However, items with magnets (eg, stereo speakers,
refrigerators, freezers, power tools) may cause the neurostimulator to switch On or Off.
Occupational environments – Commercial electrical equipment (arc welders, induction
furnaces, resistance welders), communication equipment (microwave transmitters, linear
power amplifiers, high-power amateur transmitters), and high voltage power lines may
generate enough electromagnetic interference (EMI) to interfere with neurostimulator
operation if approached too closely.
16
English
M927893A002
Information for prescribers
2007-09
M927893A_appA.fm 8/21/08
3:23 pm
Radio frequency sources – Analog and digital cellular phones, AM/FM radios, cordless
phones, and conventional wired telephones may contain permanent magnets. To prevent
undesired turning On or Off of the stimulation, these devices should be kept at least 10 cm
(4 in) away from the implanted neurostimulator.
Therapeutic magnets – Therapeutic magnets (for example, those found in bracelets, back
braces, shoe inserts and mattress pads) can cause inadvertent on or off activations of the
neurostimulator. Therefore, patients should be advised not to use them.
Theft detectors and security screening devices – Patients should be advised to use
care when approaching theft detectors and security screening devices (such as those found
in airports, libraries, and some department stores) because these devices can turn on or
turn off their neurostimulator.
When approaching these devices, patients should do the following:
1. If security personnel are present, patients should show them their neurostimulator
identification card and request a manual search. Security personnel may use a
handheld security wand, but patients should ask the security personnel to avoid placing
the wand over the neurostimulator.
2. If patients must pass through the security device, they should approach the center of
the device and walk normally (Figure 2).
a. If two security gates are present, they should walk through the middle, keeping as
far away as possible from each gate.
b. If one gate is present, they should walk as far away as possible from it.
Note: Some theft detectors may not be visible.
3. Patients should proceed through the security device. Patients should not touch, lean on
or linger near the security device.
'RXEOHVHFXULW\JDWH
6LQJOHVHFXULW\JDWH
Figure 2. Approaching security gates.
4. If patients suspect that their neurostimulator was turned off, they should make sure
someone is able to turn on the system again. (This person could be the patient, if his
or her medical condition allows it. It could also be a family member or clinician who has
been taught how to use the system.)
Information for prescribers
M927893A002
2007-09
English
17
M927893A_appA.fm 8/21/08
18
English
M927893A002
3:23 pm
Information for prescribers
2007-09
M927893A002_bc.fm
8/21/08 3:23 pm
Contacts:
Asia: Medtronic International Ltd.
Tel. 02891-4068
Fax 2591-0313
Italy: Medtronic Italia SpA
Tel. 02-241371
Fax 02-241381
Medtronic Asia Ltd.
Tel. (02)-548-1148
Fax (02)-518-4786
Australia: Medtronic Australasia Pty. Ltd.
Tel. 02-9879-5999
Fax 02-9879-5100
Austria: Medtronic Österreich GmbH
Tel. 01-24044
Fax 01-24044-100
Belgium: Medtronic Belgium S.A.
Tel. 02-456-0900
Fax 02-460-2667
Canada: Medtronic of Canada Ltd.
Tel. (1905)-826-6020
Fax (1905)-826-6620
Czech Republic: Medtronic Czechia s.r.o.
Tel. 2-965-795-80
Fax 2-965-795-89
Denmark: Medtronic-Danmark A/S
Tel. 45-32-48-18-00
Fax 45-32-48-18-01
Finland: Medtronic Finland OY/LTD
Tel. (09)-755-2500
Fax (09)-755-25018
France: Medtronic France S.A.S.
Tel. 01-5538-1700
Fax 01-5538-1800
Germany: Medtronic GmbH
Tel. 0211-52930
Fax 0211-5293100
Greece: Medtronic Hellas S.A.
Tel. 02-10-677-90-99
Fax 02-10-677-93-99
Hungary: Medtronic Hungária Kft.
Tel. 1-889-06-00
Fax 1-889-06-99
Ireland: Medtronic Ireland Ltd.
Tel. (01)-890-6522
Fax (01)-890-7220
Tel. 06-328141
Fax 06-3215812
Japan: Medtronic Japan
Tel. 3-6430-2001
Fax 3-6430-7140
Latin America: Medtronic, Inc.
Tel. (1350)-500-9328
Fax (1786)-709-4244
The Netherlands: Medtronic B.V.
Tel. (045)-566-8000
Fax (045)-566-8668
Norway: Medtronic Norge AS
Tel. 67-10-32-00
Fax 67-10-32-10
Poland: Medtronic Poland Sp. z.o.o.
Tel. (022)-465-69-00
Fax (022)-465-69-17
Portugal: Medtronic Portugal, Lda.
Tel. 21-724-5100
Fax 21-724-5199
Spain: Medtronic Ibérica, S.A.
Tel. 91-625-0400
Fax 91-650-7410
Sweden: Medtronic AB
Tel. 08-568-585-00
Fax 08-568-585-01
Switzerland: Medtronic (Schweiz) AG
Tel. 031-868-0100
Fax 031-868-0199
U.K.: Medtronic U.K. Ltd.
Tel. 01923-212213
Fax 01923-241004
USA: Medtronic, Inc.
Tel. (1-763)-505-5000
Toll-free: (1-800)-328-0810
Fax (1-763)-505-1000
M927893A002
M927893A002_bc.fm
8/21/08 3:23 pm
Manufacturer
Medtronic, Inc.
710 Medtronic Parkway
Minneapolis, MN 55432-5604
USA
Internet: www.medtronic.com
Tel. 1-763-505-5000
Fax 1-763-505-1000
Contacts for specific countries are
listed inside this cover.
Medtronic E.C. Authorized
Representative/Distributed by
Medtronic B.V.
Earl Bakkenstraat 10
6422 PJ Heerlen
The Netherlands
Tel. 31-45-566-8000
Fax 31-45-566-8668
Europe/Africa/Middle East
Headquarters
Medtronic International Trading Sàrl
Route du Molliau 31
Case Postale
CH-1131 Tolochenaz
Switzerland
Internet: www.medtronic.co.uk
Tel. 41-21-802-7000
Fax 41-21-802-7900
Asia-Pacific
Medtronic International Ltd.
Suite 1602 16/F, Manulife Plaza
The Lee Gardens, 33 Hysan Avenue
Causeway Bay
Hong Kong
Tel. 852-2891-4068
Fax 852-2591-0313
*M927893A002*
M927893A002
©Medtronic, Inc. 2007
All Rights Reserved
M927893A002
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement