Deep brain stimulator (DBS)

Electrodes in the brain driven by a chest generator, for Parkinson's, tremor or dystonia. The two ways to harm the patient: diathermy (can be fatal) and the wrong MRI - and losing stimulation can trigger a crisis.

Adult & paediatricNeurologicalManufacturer instructions for use

Also called: DBS, deep brain stimulation, deep brain stimulator, brain pacemaker, neurostimulator, Parkinson's stimulator, Activa, Percept

What it is

Deep brain stimulation uses electrodes implanted deep in the brain, connected by tunnelled leads to a pulse generator in the chest (like a pacemaker), to treat Parkinson's disease, essential tremor and dystonia (and some other conditions). The patient controls it with a handheld programmer; the settings are set by the neurology/neurosurgery team.

For the ED, the device matters in three ways. First, diathermy is contraindicated and can be lethal: the device label bars shortwave, microwave and therapeutic-ultrasound diathermy (e.g. in physiotherapy) - anywhere on the body, with the device on or off - because energy transmitted down the leads can burn the brain. Theatre electrosurgery (surgical monopolar diathermy) carries the same concern and must also be flagged, so no diathermy of any kind without device-team input. Second, MRI is conditional, model- and scan-specific, and a non-approved scan can also kill. Third, losing stimulation - battery depletion, the device switched off, lead failure - lets the underlying disease rebound, which in dystonia can be a life-threatening crisis. DBS is mostly an adult device (Parkinson's, tremor), with paediatric use mainly for dystonia.

How to recognise it

A pulse generator palpable below the collarbone (occasionally in the abdomen) with a scar, leads tunnelled up the neck to the skull, and small scalp scars/burr-hole caps.
A patient with Parkinson's disease, tremor or dystonia who has a brain stimulator and a handheld controller, and usually a device identification card.
Loss of stimulation shows as the return of the patient's disease - worsening rigidity, tremor or dystonia - which can escalate.
The generator is confused with a cardiac device on a chest x-ray; the leads run up to the head, not to the heart.

What goes wrong

Diathermy exposure (can be fatal)

A DBS patient going to theatre, or to physiotherapy, where diathermy might be used without the implant being flagged.

Red flag
Diathermy is contraindicated: 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. Flag the DBS to every surgeon, anaesthetist and physiotherapist; this is not negotiable (see the MRI/diathermy panel).

Inappropriate MRI

A DBS patient referred for MRI without device-specific checks.

Red flag
MRI is conditional, not free: Tissue lesions from component heating, especially at the lead electrodes, resulting in serious and permanent injury including coma, paralysis, or death, can occur if a contraindicated MRI scan is performed. Clear every scan against the device model with the implanting centre; prefer CT if a scan is urgent.

Loss of stimulation / disease rebound

Worsening tremor, rigidity or dystonia after the battery has depleted, the device has been switched off, or a lead has failed. In Parkinson's this can be a severe akinetic state; in dystonia it can escalate to continuous, severe spasms.

Red flag
Abruptly losing DBS can cause a rebound crisis - in dystonia, status dystonicus (continuous severe dystonia with fever, rhabdomyolysis and renal failure) is a life-threatening emergency. Restore stimulation urgently via the DBS team and support the patient (hydration, sedation, critical care as needed).

The device is not the problem

A DBS patient with chest pain, confusion, sepsis or any unrelated acute illness, where attention fixes on the implant.

Red flag
Assess and treat the acute illness normally. The DBS mainly changes what you must avoid (diathermy, some MRI) rather than the acute management itself.

The first ten minutes

Flag the DBS before any procedure. Tell surgery, anaesthetics and physiotherapy that the patient has a brain stimulator - no diathermy, and no MRI until it is cleared for the specific device.
Get the device identification card and model - MRI conditionality and settings depend on it.
If stimulation has been lost and the patient is deteriorating (especially dystonia), treat it as an emergency - involve the DBS team to restore stimulation, and support the patient; watch for hyperthermia, rhabdomyolysis and renal failure in status dystonicus.
Check the obvious reversible causes - is the device switched off, is the battery depleted, has the controller been used - while you contact the team.
For an unrelated acute illness, treat it normally and simply observe the device precautions.
Contact the neurology/neurosurgery DBS team for any stimulation failure or device concern.

Do not

Do not allow diathermy in a DBS patient.

Diathermy can transmit energy down the leads and cause brain injury or death. Surgical monopolar diathermy and physiotherapy shortwave diathermy are both dangerous; flag the implant and use alternatives.

Do not send a DBS patient for MRI without device-specific clearance.

A non-approved MRI can heat the electrodes and cause coma, paralysis or death. MRI safety is model- and scan-specific and must be cleared with the implanting centre; use CT if imaging is urgent.

Do not ignore worsening dystonia or rigidity after stimulation is lost.

Rebound after loss of DBS can escalate to status dystonicus or a severe akinetic crisis - life-threatening and needing urgent restoration of stimulation and supportive care.

Do not let the stimulator distract you from an unrelated emergency.

A DBS patient gets MI, sepsis and everything else; the device changes what to avoid, not the resuscitation. Treat the acute illness on its merits.

Who owns it

The neurology / functional neurosurgery (DBS) team owns the device, often at a regional centre. Tell them the indication (Parkinson's, tremor, dystonia), the model from the card, whether stimulation has been lost and why, and the clinical picture. Involve critical care for status dystonicus or airway compromise.

MRI and diathermy with an implanted neuro device

Three implanted neuro devices turn two routine hospital exposures - diathermy and MRI - into potentially lethal ones. The rule is the same for all of them: identify the device from the patient's card, and clear MRI and diathermy with the implanting centre before either happens. Never assume a scan or an operation is safe because the patient 'has had one before'.

Diathermy can kill - deep brain stimulation above all: The device label bars shortwave, microwave and therapeutic-ultrasound diathermy - anywhere on the body, with the system on or off. For DBS the manufacturer is explicit: 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. Theatre electrosurgery (surgical monopolar diathermy) carries the same risk and must also be flagged - to every surgeon, anaesthetist and physiotherapist.
MRI is conditional, never assumed: MRI is not a simple yes/no - it depends on the device model, the coil and the scan. For DBS a contraindicated scan is lethal: Tissue lesions from component heating, especially at the lead electrodes, resulting in serious and permanent injury including coma, paralysis, or death, can occur if a contraindicated MRI scan is performed. For a cochlear implant, MRI can damage your implant so is best avoided if an alternative scan is possible. Clear every scan with the implanting centre first.
Cochlear implant: diathermy and other energy: Monopolar diathermy can be used below the neck as long as care is taken to ensure that current does not pass near the head: it is safer to use bipolar diathermy where possible. And Procedures such as transcranial magnetic stimulation (TMS), electro-convulsive therapy (ECT) and neurostimulation, should not be undertaken.
Programmable shunt valves and stray magnets: Many CSF shunt valves are programmable - the closing pressure to be altered externally using a special magnetic device - so a stray magnet can change the setting, and it can lead to problems following an inadvertent change of pressure. MRI is a recognised cause of inadvertent reprogramming (per the valve manufacturers' labelling), so after any MRI a programmable valve must be checked and reset by neurosurgery.
What to do: Get the device identification card and the model; flag the implant to everyone planning diathermy, MRI, TMS or ECT; and contact the implanting centre before proceeding. When in doubt, choose an alternative to MRI (e.g. CT) and avoid diathermy entirely.

Who to call

The team and the criteria are national. The phone number is local, and this tool does not know it. Find it once, now, and write it on the department's own card — that is the part no website can do for you.

Say the device name first: Open with laryngectomy, LVAD, shunt — the single word changes who comes and what they bring. Do not bury it in the history.
Say what you have already established: Whether the device is patent, whether it has been removed or disturbed, and what you have already tried. The specialist is deciding whether to walk or run.
Ask who owns it out of hours: Device ownership and the on-call route often differ from the implanting specialty, and it is frequently a regional centre rather than your own hospital.
The patient's own team is a resource, not an afterthought: Named nurse specialists, home-care companies and device helplines answer questions nobody else can, and the patient usually has the number.

When the device is not the problem

A patient with a device gets pneumonia, sepsis, pulmonary oedema and myocardial infarction at the same rate as everybody else. The device is the most visible thing about them and it attracts the whole assessment.

The NTSP says it out loud: The project's own manual warns that patients with tracheostomies can become unwell with all the problems that other patients get too. It is easy to become fixated with the tracheostomy. The same sentence applies to every device in this tool.
Clear the device, then leave it: Establish that the device is doing its job — the stoma is patent, the line draws back, the pump is running — and then assess the patient as you would anyone else.
The anchoring runs both ways: The opposite error is treating a device complication as a medical illness: a blocked gastrostomy read as vomiting, a baclofen pump failure read as sepsis.

NTSP manual — Red flags · read in full

What the patient will be carrying

DBS patients carry a device identification card with the model and settings and have a handheld controller; they and their carers usually know the implanting centre and can tell you if stimulation has changed.

Scope of this page

This page covers the ED-relevant hazards of a deep brain stimulator: the diathermy contraindication, conditional MRI, and the rebound crisis when stimulation is lost. It does not teach DBS programming, battery replacement or troubleshooting the stimulation settings (the DBS team's role). The diathermy and MRI hazards are from the device label; the loss-of-stimulation and status-dystonicus content is established clinical practice rather than from that label. DBS is predominantly an adult device; paediatric use is mainly for dystonia (the US label from age 12) and is directed by the specialist team.

Sources

Medtronic deep brain stimulation system - Indications, Safety and Warnings (FDA-approved labelling): diathermy and MRI contraindications · read in full