How should analgesia be prescribed pre-operatively (pre-op), intra-operatively (intra-op), and post-operatively (post-op)?

Comprehensive Perioperative Analgesia Management

Multimodal analgesia should be implemented pre-operatively, intra-operatively, and post-operatively to optimize pain control, minimize opioid use, and enhance recovery after surgery. This approach reduces morbidity, mortality, and improves quality of life by preventing complications associated with inadequate pain control and excessive opioid use 1.

Pre-operative Analgesia

Medications to administer before surgery:

• Paracetamol (acetaminophen): 1g orally 2 hours pre-operatively 1
• NSAIDs or COX-2 inhibitors: Unless contraindicated (renal dysfunction, bleeding risk, etc.) 1
• Dexamethasone: Single IV dose (4-8mg) for its analgesic and antiemetic effects 1
• Oral carbohydrate drinks: Up to 2 hours before surgery to reduce insulin resistance 1

Pre-operative considerations:

• Assess for pre-existing chronic pain conditions and opioid tolerance 1
• Consider pre-operative nerve blocks for specific procedures (e.g., interscalene block for shoulder surgery) 1
• Avoid routine use of gabapentinoids due to insufficient evidence of benefit and potential for harm in older patients 1

Intra-operative Analgesia

Regional techniques (procedure-specific):

• Neuraxial anesthesia (spinal/epidural): First-line for major abdominal, pelvic, and lower limb surgeries 1
  • For cesarean delivery: Intrathecal morphine (50-100 μg) or diamorphine (300 μg) 1
  • For open abdominal surgery: Thoracic epidural with low-dose local anesthetic and opioid 1
• Peripheral nerve blocks:
  • Interscalene block for shoulder surgery 1
  • TAP blocks, quadratus lumborum, or ESP blocks for abdominal surgery 1
  • Femoral or posterior lumbar plexus blocks for hip surgery 1
• Local anesthetic infiltration: At surgical site prior to incision and/or at wound closure 1

Systemic medications:

• Paracetamol: IV 1g if not given pre-operatively 1
• NSAIDs/COX-2 inhibitors: IV formulations if appropriate 1
• Dexamethasone: If not given pre-operatively 1
• Opioids: Remifentanil 0.05-2 mcg/kg/min titrated to effect for intraoperative analgesia 2
• Controlled hypotension: Not recommended due to risk of reduced cerebral perfusion 1

Post-operative Analgesia

Immediate post-operative period:

• Continue regional techniques initiated intraoperatively:
  • Epidural infusion for 48-72 hours for major open surgery 1
  • Continuous peripheral nerve blocks where appropriate 1
• Transition to oral medications as soon as possible 1

Systemic medications:

• Paracetamol: 1g every 6 hours (maximum 4g/24h) 1
• NSAIDs/COX-2 inhibitors: Regular dosing unless contraindicated 1
• Opioids: Use as rescue analgesia rather than primary treatment 1
  • For immediate post-operative pain, consider PCA if regional techniques unavailable or contraindicated 1
  • Transition to immediate-release oral opioids when appropriate 1
  • Minimize home-going opioid prescriptions 1

Adjunctive therapies:

• Transcutaneous electrical nerve stimulation (TENS) 1
• Music via headphones during recovery 1
• Abdominal binders for abdominal surgery 1

Special Considerations

Laparoscopic vs. open surgery:

• Laparoscopic approaches reduce analgesic requirements 1
• For laparoscopic procedures, regional techniques may be less necessary 1

Opioid-tolerant patients:

• Higher doses of non-opioid analgesics
• Consider ketamine infusion intraoperatively
• Early involvement of acute pain service 1

Monitoring for complications:

• Monitor sedation scores and respiratory rate to detect opioid-induced ventilatory impairment 1
• Assess for PONV and treat proactively with multimodal antiemetics 1

Common Pitfalls to Avoid

1. Overreliance on opioids: Use multimodal approach to minimize opioid requirements and side effects 1
2. Inadequate regional anesthesia: Ensure proper placement and dosing of regional blocks 1
3. Poor transition planning: Have a clear plan for transitioning from IV to oral analgesia 1
4. Neglecting non-pharmacological approaches: Incorporate physical modalities and psychological support 1
5. One-size-fits-all approach: Consider surgical procedure, patient factors, and comorbidities when selecting analgesic regimen 1

By implementing this comprehensive multimodal approach to perioperative analgesia, clinicians can optimize pain control, reduce opioid-related complications, and enhance recovery after surgery.