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Baclofen Withdrawal

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Baclofen Withdrawal, Baclofen Pump, Baclofen Pump Malfunction, Baclofen Intrathecal Pump

  • Background
  1. Baclofen is used to reduce severe spasticity (e.g. spinal cord injury, Cerebral Palsy, Multiple Sclerosis)
  2. Oral Baclofen poorly penetrates blood brain barrier, and requires intolerable oral doses to offer effect
  3. Instead, intrathecal Baclofen has fewer side effects and may be used at low dose
  • Dosing
  1. Baclofen 50-100 mcg/day via Intrathecal Pump (up to 900 mcg) and slowly titrate to effect
  2. Small dose modifications can have significant effects on patient findings (due to direct CSF drug delivery)
  • Causes
  • Baclofen Withdrawal
  1. Empty medical reservoir
  2. Mistakes in Baclofen Pump programming
  3. Pump battery failure
  4. Catheter malfunction (kinked, migrated)
  • Findings
  • Baclofen Withdrawal
  1. Baclofen Withdrawal may be severe and life threatening
  2. Timing of withdrawal
    1. Onset within 48-96 hours of stopping intrathecal Baclofen (may have onset within 12 hours)
  3. Mild to moderate
    1. Spasticity returns
    2. Pruritus
    3. Anxiety
    4. Disorientation
  4. Severe
    1. Hyperthermia
    2. Tachycardia
    3. Myoclonus
    4. Seizures
    5. Coma
    6. Hallucinations, Delirium, Delusions or paranoia (related to Norepinephrine and Dopamine release)
    7. Baclofen Withdrawal results in hemodynamic instability, Seizures
    8. May present with signs similar to Sepsis
      1. May present with Tachycardia, Tachypnea, fever and confusion (all consistent with Sepsis)
      2. However, in contrast with Sepsis, Baclofen Withdrawal presents with Hypertension
  • Imaging
  1. Abdominal AP and lateral
    1. Evaluate for catheter migration
  2. Catheterogram
    1. May be needed to identify catheter problems
  • Management
  • Baclofen Withdrawal
  1. Urgently consult neurosurgery
  2. General supportive measures
    1. ABC Management
    2. Intravenous FluidResuscitation
  3. Replace Baclofen
    1. Baclofen cannot be effectively replaced orally or intravenously (needs intrathecal delivery)
    2. Refill empty Baclofen reservoir
    3. Inject Baclofen into the pump's side port OR via intrathecal space via spinal needle
      1. Typically performed by neurosurgery
    4. Interrogate Baclofen Pump
  4. Other measures: GABA-A Agents (prevent Seizures, control spasticity)
    1. Benzodiazepines
    2. Propofol infusion may also counter withdrawal effects
      1. Initiate early before significant withdrawal, hemodynamic instability
  5. Other agents that have been used in case reports effectively (but inadequate evidence)
    1. Dantrolene
    2. Cyproheptadine
  • Prevention
  • Baclofen Withdrawal
  1. Do not stop Baclofen abruptly (taper over weeks)
  • References
  1. Mishler and Lovecchio (2017) Crit Dec Emerg Med 31(11): 15-20
  2. Orman and Swaminathan in Herbert (2017) EM:Rap 17(1): 1