Baclofen Withdrawal

Aka: Baclofen Withdrawal, Baclofen Pump Malfunction

1. See Also
   1. Baclofen
   2. Intrathecal Pump
   3. Drug Withdrawal
   4. Baclofen Poisoning
2. Background
   1. Baclofen is used to reduce severe spasticity (e.g. spinal cord injury, Cerebral Palsy, Multiple Sclerosis)
      1. Oral Baclofen poorly penetrates blood brain barrier, and requires intolerable oral doses to offer effect
   2. Instead, intrathecal Baclofen has fewer side effects and may be used at low dose
      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)
3. Precautions
   1. Baclofen Withdrawal is a life-threatening emergency presenting with hemodynamic instability and Altered Mental Status
   2. Withdrawal events typically occur within 72 hours of pump manipulation or medication administration
4. Causes
   1. Empty medical reservoir
   2. Mistakes in Baclofen Pump programming
   3. Pump battery failure
   4. Catheter malfunction (kinked, migrated)
5. Findings
   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. Muscle Spasticity returns
      2. Pruritus
      3. Anxiety
      4. Disorientation
   4. Severe
      1. Hyperthermia (Fever)
      2. Tachycardia
      3. Myoclonus
      4. Seizures
      5. Hemodynamic Instability
      6. Hypertension
      7. Altered Level of Consciousness
         1. Coma
         2. Hallucinations, Delirium, Delusions or paranoia (related to Norepinephrine and Dopamine release)
6. Differential Diagnosis
   1. Autonomic Dysreflexia
   2. Malignant Hyperthermia
   3. Serotonin Syndrome
   4. Neuroleptic Malignant Syndrome
   5. Meningitis
   6. 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
7. Labs
   1. Creatine Kinase
   2. Urine Myoglobin
   3. Serum Creatinine
   4. Blood Urea Nitrogen
8. Imaging
   1. Abdominal AP and lateral
      1. Evaluate for catheter migration
   2. Catheterogram
      1. May be needed to identify catheter problems
9. Management
   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
         1. Pump is implanted into Abdomen
         2. Tubing runs subcutaneously from port, to the patient's flank and into lumbar spinal canal
      5. Consider Lumbar Puncture with Baclofen intrathecal injection
         1. Indicated in severe withdrawal and unable to access Baclofen Pump or tubing
         2. Consult Anesthesia
   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
10. Complications
    1. Rhabdomyolysis
    2. Disseminated Intravascular Coagulation
    3. Cardiac Arrest
11. Prevention
    1. Do not stop Baclofen abruptly (taper over weeks)
12. 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
    3. Riley and LoVecchio (2021) Crit Dec Emerg Med 35(5):28