What is the recommended approach for managing withdrawal from ketamine, morphine, and baclofen?

Management of Ketamine, Morphine, and Baclofen Withdrawal

Baclofen withdrawal is the most dangerous of these three substances and requires immediate continuation or reinstitution of therapy, while morphine withdrawal should be managed with opioid replacement and gradual taper, and ketamine withdrawal lacks established protocols but may paradoxically benefit from low-dose ketamine for symptom management.

Baclofen Withdrawal: The Critical Priority

Immediate Management

• Continue baclofen therapy without interruption to prevent potentially life-threatening withdrawal, even in perioperative settings including the day of operation 1, 2
• If withdrawal has already begun, reinstitute baclofen therapy immediately as this is the primary and most effective treatment 2
• Abrupt discontinuation can lead to visual and auditory hallucinations, anxiety, agitation, delirium, fever, tremors, tachycardia, and seizures 1, 2

Life-Threatening Complications

• Intrathecal baclofen withdrawal is especially dangerous and can cause high fever, altered mental status, rebound spasticity, muscle rigidity leading to rhabdomyolysis, multiorgan failure, and death 1, 2
• Withdrawal symptoms from intrathecal baclofen can evolve over 1-3 days but may become fulminant if not recognized promptly 2
• Perioperative management of intrathecal baclofen requires specialist consultation 1

Adjunctive Treatment Options

• Benzodiazepines can be used to manage withdrawal symptoms if baclofen reinstitution is delayed 3
• Propofol may be considered for refractory symptoms 3
• Skeletal muscle relaxants and tizanidine are alternative adjunctive options 3

Prevention Strategy

• Gradual dose reduction is essential when discontinuing therapy to prevent withdrawal symptoms 2
• Never abruptly discontinue baclofen in patients on long-term therapy 1, 2

Morphine (Opioid) Withdrawal Management

Replacement Therapy Approach

• Continue patients on stable doses of opioid at their current dose when managing withdrawal 1
• For opioid-dependent patients, higher doses of opioid analgesics at shortened intervals are required due to tolerance 1
• Morphine is the opioid of choice for managing withdrawal symptoms in opioid-dependent patients 1

Dosing Strategy for Active Withdrawal

• Opioid-naïve patients can be started on 2 mg intravenous morphine boluses, titrated to effect 1
• Patients on continuous morphine infusions can receive bolus doses of 2× the hourly infusion rate every 15 minutes as needed for breakthrough symptoms 1
• If a patient requires 2 bolus doses in an hour, double the infusion rate 1
• Opioids should be titrated to symptoms with no dose limit 1

Alternative Approaches for Maintenance Therapy

• Converting to methadone at 30-40 mg daily can prevent acute withdrawal in most patients and allows for easier management with additional opioid analgesics 1
• If withdrawal persists on methadone, increase subsequent daily doses in 5-10 mg increments 1

Adjunctive Medications

• Benzodiazepines can be used in combination with opioids for withdrawal management 1
• Baclofen has been studied as an alternative to clonidine for opioid withdrawal, with effectiveness in managing both physical and mental symptoms and lower incidence of hypotension 4
• Antinauseants should be ordered pro re nata with opioids 1

Ketamine Withdrawal Management

Evidence Gap and Emerging Approaches

• No established guidelines exist for ketamine withdrawal management as the provided evidence focuses on ketamine as a treatment adjunct rather than withdrawal from ketamine itself
• Paradoxically, ketamine at sub-dissociative doses (sublingual 16 mg) has shown promise in managing withdrawal from other substances, suggesting potential self-management applications 5

Ketamine as Adjunctive Treatment

• Ketamine infusion (0.5 mg/kg over 30 minutes) has demonstrated significant improvement in severe benzodiazepine withdrawal when standard treatments fail 6
• Sub-dissociative doses of ketamine (sublingual 16 mg, bioequivalent to 3-6% of anesthetic dose) can reduce or eliminate spontaneous opioid withdrawal symptoms 5
• Most patients tolerate sub-dissociative ketamine doses without significant cognitive changes 5

Critical Assessment and Monitoring

Symptom Assessment

• Use standardized scoring systems to assess pain, agitation, and respiratory distress during withdrawal management 1
• Use objective signs such as tachypnea, grimacing, rising respiratory rate, and accessory muscle use to assess discomfort 1
• Document the rationale for giving any dose of comfort medication during withdrawal 1

Common Pitfalls to Avoid

• Never abruptly discontinue baclofen - this is the most dangerous error with potentially fatal consequences 1, 2
• Do not underestimate opioid dose requirements in tolerant patients - higher doses at shortened intervals are necessary 1
• Avoid treating agitation with sedatives before adequately treating pain and dyspnea with opioids 1
• Be cautious with increased sensitivity to full opioid agonists if buprenorphine therapy is abruptly discontinued, as this increases risk of sedation and respiratory depression 1