What is the effect of Quetiapine (antipsychotic medication) on anesthesia?

Effects of Quetiapine on Anesthesia

Quetiapine can cause refractory hypotension during anesthesia and should be used with caution in the perioperative period, especially in patients with cardiovascular concerns.

Cardiovascular Effects During Anesthesia

Quetiapine, an atypical antipsychotic, has significant effects on anesthesia administration that clinicians should be aware of:

• Hypotension risk: Quetiapine has α-adrenergic antagonist properties that can lead to refractory hypotension during general anesthesia 1. This hypotension may be particularly resistant to standard vasopressors and more responsive to vasopressin.

• Hemodynamic concerns: According to the European Heart Journal guidelines, quetiapine is associated with hypotension in approximately 10% of patients 2. This risk is particularly important in patients with cardiovascular disease or hemodynamic instability.

• Bradycardia potential: Like other sedatives, quetiapine can ablate sympathetic tone, potentially resulting in vasodilation, hypotension, and bradycardia during anesthesia 3.

Perioperative Management Considerations

Pre-anesthesia Assessment

• Identify patients on quetiapine therapy before surgery
• Assess cardiovascular status and risk factors
• Consider the indication for quetiapine use (psychosis vs. off-label for insomnia)
• Evaluate for potential drug interactions with anesthetic agents

Anesthesia Management

1. Induction modifications:

   • Consider using reduced doses of induction agents in patients on quetiapine
   • Be prepared for more pronounced hypotension during induction
   • Have vasopressors readily available, particularly vasopressin

2. Intraoperative monitoring:

   • Implement close hemodynamic monitoring
   • Consider arterial line placement for continuous blood pressure monitoring in high-risk patients
   • Monitor for prolonged sedative effects

3. Fluid management:

   • Consider individualized goal-directed fluid therapy 2
   • Avoid both restrictive and liberal strategies

Special Considerations

• Elderly patients: Older adults are particularly vulnerable to quetiapine's hemodynamic effects during anesthesia. Recent research shows increased mortality risk even with low-dose quetiapine in elderly patients 4.

• Patients with OSA: Quetiapine may worsen obstructive sleep apnea through sedative effects and weight gain 2, potentially complicating airway management during anesthesia.

• Delirium prevention: Despite its cardiovascular risks, low-dose quetiapine (12.5 mg) given preoperatively has been shown to reduce postoperative delirium incidence and improve sleep quality in elderly orthopedic patients 5.

Practical Recommendations

1. Continue or discontinue?

   • For patients on chronic quetiapine therapy for psychiatric indications, generally continue the medication to avoid withdrawal or psychiatric decompensation
   • For patients using quetiapine for off-label indications like insomnia, consider temporary discontinuation before surgery if cardiovascular risk is high

2. Anesthetic technique selection:

   • Consider regional anesthesia techniques when appropriate to minimize cardiovascular effects
   • If general anesthesia is required, consider using agents with minimal hemodynamic effects

3. Post-anesthesia monitoring:

   • Extend post-anesthesia monitoring in patients on quetiapine
   • Be vigilant for prolonged sedation and delayed emergence
   • Monitor for hypotension in the recovery period

Pitfalls to Avoid

• Underestimating hypotension risk: Be prepared for potentially severe and refractory hypotension that may not respond well to standard vasopressors.

• Overlooking drug interactions: Quetiapine is metabolized by CYP3A4, so interactions with anesthetic agents using the same pathway may occur 6.

• Assuming all antipsychotics have similar effects: Quetiapine has a unique receptor binding profile with greater serotonin 5-HT2 affinity than dopamine D2 affinity, creating a distinct side effect profile compared to other antipsychotics 7.

• Ignoring the benefits: While cardiovascular risks exist, quetiapine may provide benefits for certain surgical populations through reduced postoperative delirium and improved sleep quality 5.