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Intrathecal baclofen therapy



  • Introduction

    Baclofen is a GABA ß-agonist with muscle relaxing properties and is administered to reduce spasticity or dystonia.  

    Patient groups receiving ITB may include children and adolescents with:Ìý

    • Cerebral PalsyÌý
    • Acquired brain injuryÌý
    • Severe metabolic or neurodegenerative conditions associated with spasticity and/or dystoniaÌý

    Long term continuous ITB therapy is administered via a surgically implanted programmable pump.Ìý Surgical and hardware complications are managed by the Neurosurgical team. Ìý

    The ITB pump programming and ongoing patient care is managed by the patient’s primary ITB team which is either:

    • Neurodevelopment & Disability
    • ¸é±ð³ó²¹²ú¾±±ô¾±³Ù²¹³Ù¾±´Ç²Ô 

    Aim

    The aim of the guideline is to outline the acute emergency and inpatient care for patients requiring Intrathecal Baclofen (ITB) therapy for all clinicians at RCH.Ìý

    Key Points

    1. ITB is administered via an implanted pumpÌý
    2. ITB pumps should only be accessed or programmed by a clinician familiar with the ITB therapy and programmingÌý
    3. Notify the primary ITB treating team for presentations to Emergency Department
    4. Pump malfunction causing withdrawal or overdose can be life-threatening and requires urgent intervention.
    5. MRI scans can stall the pump motor. Ìý

    Initial Assessment of child with an ITB pump who presents to EmergencyÌý

    The following steps are recommended in the initial assessment of the child with an ITB pump:

    • Physical exam and comprehensive history
    • Confirm date of last pump refill and next pump refill.
    • Assess for pump alarms.Ìý Pump alarms can be quiet and as infrequent as every hour, parents have mistaken the pump alarm for the sounds of an electronic device or toy.Ìý

    A child with an ITB pumpÌýin situÌýmay present to the emergency department for several reasons not related to ITB therapy. Consider differential diagnoses such as pain, anxiety, infection/sepsis/meningitis, epilepsy, malignant hyperthermia, intracranial haemorrhage, neuroleptic-malignant or serotonin syndrome

    If concerned about baclofen overdose or withdrawal contact the on-call consultant of the child’s ITB treating team (NeurodevelopmentÌý& Disability or Rehabilitation Department).

    Complications of Intrathecal Baclofen Therapy

    Ìý Cause Symptoms Emergency Management
    Overdose

    A pump or catheter malfunction resulting in the over-delivery of IT baclofen

    Ìý

    Programming error

    Ìý

    Patient sensitivity to dose of ITB

    Mild – Moderate Symptoms:

    • Weakness (beginning in the lower limbs)
    • Tiredness to somnolence
    • Dizziness,
    • Constipation
    • Urinary retention,
    • Nausea & Vomiting
    • Headache
    • Drooling
    Ìý

    Severe symptoms:

    • Hypotonia
    • Hypothermia
    • Bradycardia
    • Seizures
    • Loss of consciousness progressing to coma
    Ìý

    Differential diagnosis:

    Ìý

    Hypoglycaemia, electrolyte imbalance, epilepsy, infection/sepsis/meningitis, intracranial haemorrhage

    Initiate MET as indicated

    Ìý

    Notify the patient’s primary ITB team via switch

    Ìý

    Review pump function. Cease or decrease ITB as indicated

    Ìý Ìý Ìý Ìý
    Withdrawal (underdose)

    A pump or catheter malfunction resulting in the under-delivery or cessation of IT baclofen delivery

    Ìý

    A break or leak in the catheter

    Ìý

    Disconnection of the catheter from the pump.Ìý

    Ìý

    Movement of the catheter at a spinal level

    Ìý

    Programming error

    Ìý Ìý

    Mild - Moderate Symptoms:

    • Increase in spasticity, often worse than pre-pump baseline
    • Pruritus
    • Irritability & Agitation
    • Febrile >38°°ä
    • Labile blood pressure
    • Tachycardia,
    • Headache,
    • Disorientation,
    • Hallucination
    Ìý

    Severe symptoms:

    • Extreme CNS hyper excitability
    • Myoclonus
    • Fever >39
    • Altered mental status to coma Seizures
    • Rhabdomyolysis
    • Disseminated intravascular coagulation
    • Multisystem organ failure Autonomic dysregulation to cardiac arrest if insufficiently treated
    Ìý

    Most common cause of life-threatening event.

    Ìý

    Initiate MET as indicated.Ìý A confirmed withdrawal should be managed in PICU.

    Ìý Ìý

    If withdrawal is suspected but vital signs are within acceptable limits, notify primary ITB team urgently with aim to restore intrathecal dose of baclofen as quickly as possible.

    Ìý

    Depending on severity of symptoms consider sequential dosing with:

    • Baclofen p.o. 10 mg-20 mg
    • Diazepam p.o. (5-10 mg)
    • Oral cyproheptidineÌý(4-8 mg)
    Ìý

    If not effective consider Intravenous diazepam: 1-2mg/hr continuously, or IV infusion of clonidine up to 1-5 mcg/kg/hour.

    Infection

    Surgical complication

    Ìý

    Pump refill

    Ìý

    Colonisation of bacteria in hardware of pump/catheter

    Temperature > 38 °CÌý

    Ìý

    Redness or inflammation of woundÌýor around pump

    Ìý

    Swelling around pumpÌý

    Inform neurosurgical team for review.Ìý

    Ìý

    Inform primary ITB team.Ìý

    Ìý

    Commence septic work up:Ìý

    • TemperatureÌý
    • UrinalysisÌýMC&S
    • FBEÌý
    • Blood culturesÌý
    • Respiratory assessment
    • Chest X-ray
    Ìý

    Consult with neurosurgery before considering Lumbar PunctureÌý

    CSF LeakÌý

    Catheter crack/breakÌý

    Ìý

    Catheter disconnection

    Ìý

    Leak around insertion site ofÌýcatheterÌýinto theÌýintrathecal space

    Ìý

    Catheter migration out of IT space

    • Postural headaches
    Ìý
    • Swelling around pump and abdomen
    Ìý
    • Clear fluid discharge around surgical wound

    Urgently notify Neurosurgical team and ITB treating team

    Ìý

    Investigations may include:Ìý

    Imaging of the pump and catheter

    Ìý

    Nuclear medicine/Dye flow study under video fluoroscopy- should be performed by a neurosurgeon

    Ìý

    Surgical exploration of pump and catheter

    Medication interactions

    Patients receiving ITB therapy may have an increased sensitivity to opiates.

    Ìý

    Opiates should be given with caution, and in smaller doses in children with ITB pumps as respiratory depression may be more than anticipated.Ìý

    Ìý
    • As for Overdose

    Initiate MET as indicated

    Ìý

    Cease or reduce dose of opioids

    Ìý

    Consider using other medications

    Ìý

    Notify the patient’s treating team

    Ìý

    Clinical Considerations

    Considerations for MRI, Lumbar Puncture, Epidural and Surgical cauterisation

    Procedure Considerations
    MRI
    • The ITB pump motor can stall during an MRI.Ìý
    • Prior to the MRI coordinate with the patient’s primary ITB team to ensure they are available to program the pump at the completion of the MRI, in the hour after
    Lumbar Puncture & Epidural
    • Notify the Neurosurgical team
    • Notify the ITB treating team
    • Prior to performing a lumbar puncture check x-ray as catheter loops subcutaneously beyond incision site.Ìý
    • Lumbar puncture may be performed if the proceduralist is confident that the catheter can be avoided.Ìý Micro holes in the catheter from inadvertent injury can lead to baclofen withdrawal.Ìý
    • Consider using an image intensifier
    Surgery Intra-operative risks to ITB include:
    • Interaction of ITB with other medications, particularly opioids
    • Risk of damage to catheter during surgery
    • Pump malfunction
    • Monopolar cautery can interfere with the pump program.Ìý Bipolar cautery should be used as an alternative.Ìý
    • Notify the Neurosurgical team and ITB treating team with concerns

    Ìý

    Post-operative management of Intrathecal Baclofen Therapy (ITB) pump placement

    Initial post-operative management (days 0- 2)Ìý

    • Routine post anaesthetic observations
    • Routine post-operative neurological observations. See nursing assessment for more information.
    • Observe dressing of abdominal and lumbar wounds hourly for 24 hours then observe with routine observations. Ìý
    • To reduce risk of CSF leak the patient must lie flat for 48 hours. Do NOT tilt bed. Head should remain level with bottom.
    • Patient can move from side to side and back to front.
    • Patient should remain Nil Orally until bowel sounds are audible, as there is a risk of a paralytic ileus.ÌýÌý
    • Replace dressings if faecally contaminated. Use the same type of dressing as applied in operating theatre. Typically, Mepilex BoarderÓ™ dressing is used.Ìý
    • Report any discharge or CSF leakage to neurosurgical team immediately.  Ìý
    • Patients who are incontinent may require an Indwelling Catheter (IDC) to be inserted in theatre reduce the risk of wound contamination.  The IDC should remain in situ until the patient is mobilising as usual.  Ìý

    Ongoing inpatient management (day 2 to discharge)

    • The ITB pump will be reviewed and re-programmed as required by the treating ITB team Ìý
    • Continue routine observations including the patient's wound site and dressing until patient is discharged. Ìý
    • Baclofen is known to decrease gastrointestinal motility and cause constipation.  Document all bowel actions and consider aperients if no bowel action in a 24-hour period.ÌýÌý
    • Refer to orthotics for fitting of a neoprene belt. This provides protection around the pump and should be worn when patient is out of bed for the first three months post insertion. NB: The belt shouldn’t be too tight; it is for support not compression of abdomen.  Ìý
    • Refer to Physiotherapy and Occupational Therapy for review of seating in wheelchair and car seat.Ìý
    • ÌýAP and lateral x-ray to check catheter position and height postoperatively once the patient is mobilising. Ìý

    DischargeÌý

    • Able to sit comfortably out of bedÌý
    • Bowels openÌý
    • Returned to baseline diet (either oral or enteral feeding or both)Ìý
    • Pain is well controlled and only requires breakthrough oral pain reliefÌý
    • Parents/carers have sound understanding of how to care for ITB at home, including ITB complications and pump alarmsÌý
    • Review by ITB treating team, with appointment for review organisedÌý
    • Appointment with Neurosurgeon six- eight weeks post operatively organisedÌý
    • Review by physiotherapy and occupational therapy
    • Review by ITB Clinical Nurse ConsultantÌý

    Companion Documents

    Evidence Table

    Intrathecal Baclofen Evidence Table - coming soon.


    Please remember to


    The revision of this nursing guideline was coordinated by Ingrid Sutherland, Clinical Nurse Consultant, Neurodevelopment and Disability, and Lillian Stagoll, CNC, Neurology, and approved by the Nursing Clinical Effectiveness Committee. Updated February 2023.ÌýÌý