II. Background
-
Baclofen is used to reduce severe spasticity (e.g. Spinal Cord Injury, Cerebral Palsy, Multiple Sclerosis)
- Oral Baclofen poorly penetrates blood brain barrier, and requires intolerable oral doses to offer effect
- Instead, intrathecal Baclofen has fewer side effects and may be used at low dose
- Baclofen 50-100 mcg/day via Intrathecal Pump (up to 900 mcg) and slowly titrate to effect
- Small dose modifications can have significant effects on patient findings (due to direct CSF drug delivery)
III. Precautions
- Baclofen Withdrawal is a life-threatening emergency presenting with hemodynamic instability and Altered Mental Status
- Withdrawal events typically occur within 72 hours of pump manipulation or medication administration
IV. Causes
- Empty medical reservoir
- Mistakes in Baclofen Pump programming
- Pump battery failure
- Catheter malfunction (kinked, migrated)
V. Findings
- Baclofen Withdrawal may be severe and life threatening
- Timing of withdrawal
- Onset within 48-96 hours of stopping intrathecal Baclofen (may have onset within 12 hours)
- Mild to moderate
- Muscle Spasticity returns
- Pruritus
- Anxiety
- Disorientation
- Severe
- Hyperthermia (Fever)
- Tachycardia
- Myoclonus
- Seizures
- Hemodynamic Instability
- Hypertension
- Altered Level of Consciousness
- Coma
- Hallucinations, Delirium, Delusions or paranoia (related to Norepinephrine and Dopamine release)
VI. Differential Diagnosis
- Autonomic Dysreflexia
- Malignant Hyperthermia
- Serotonin Syndrome
- Neuroleptic Malignant Syndrome
- Meningitis
-
Sepsis
- May present with Tachycardia, Tachypnea, fever and confusion (all consistent with Sepsis)
- However, in contrast with Sepsis, Baclofen Withdrawal presents with Hypertension
VIII. Imaging
- Abdominal AP and lateral
- Evaluate for catheter migration
- Catheterogram
- May be needed to identify catheter problems
IX. Management
- Urgently consult neurosurgery
- General supportive measures
- Replace Baclofen
- Baclofen cannot be effectively replaced orally or intravenously (needs intrathecal delivery)
- Refill empty Baclofen reservoir
- Inject Baclofen into the pump's side port OR via intrathecal space via spinal needle
- Typically performed by neurosurgery
- Interrogate Baclofen Pump
- Pump is implanted into Abdomen
- Tubing runs subcutaneously from port, to the patient's flank and into lumbar spinal canal
- Consider Lumbar Puncture with Baclofen intrathecal injection
- Indicated in severe withdrawal and unable to access Baclofen Pump or tubing
- Consult Anesthesia
- Other measures: GABA-A Agents (prevent Seizures, control spasticity)
- Benzodiazepines
- Propofol infusion may also counter withdrawal effects
- Initiate early before significant withdrawal, hemodynamic instability
- Other agents that have been used in case reports effectively (but inadequate evidence)
X. Complications
XI. Prevention
- Do not stop Baclofen abruptly (taper over weeks)
XII. References
- Mishler and Lovecchio (2017) Crit Dec Emerg Med 31(11): 15-20
- Orman and Swaminathan in Herbert (2017) EM:Rap 17(1): 1
- Riley and LoVecchio (2021) Crit Dec Emerg Med 35(5):28