Preoperative opioid consumption increases morphine requirement after leg amputation.

Area of Science:

• Anesthesiology
• Pain Management
• Surgical Oncology

Background:

• Effective pain management after leg amputation is crucial for patient recovery.
• Preoperative opioid use may influence postoperative analgesic requirements.
• Combined regional and general anesthesia is employed for leg amputations.

Purpose of the Study:

• To evaluate the impact of preoperative opioid consumption on postoperative morphine requirements in patients undergoing leg amputation.
• To investigate the association between chronic opioid use and postoperative pain after amputation.

Main Methods:

• Prospective observational study including patients undergoing leg amputation.
• Preoperative popliteal sciatic nerve catheter placement with ropivacaine infusion.
• Postoperative analgesia included acetaminophen, continuous ropivacaine infusion, and IV morphine based on visual analogue scale (VAS) pain scores.
• Patients were categorized into 'Preop opioids' and 'No preop opioid' groups.

Main Results:

• Twenty-two patients were analyzed (12 Preop opioids, 10 No preop opioid).
• Postoperative opioid consumption (days 1-3 and day 7) was significantly higher in the Preop opioids group compared to the No preop opioid group.
• The median morphine equivalent consumption was 52 mg in the Preop opioids group versus 0 mg in the No preop opioid group (P=0.02).

Conclusions:

• Preoperative opioid consumption is linked to increased postoperative morphine requirements after leg amputation.
• Regional anesthesia techniques do not fully mitigate the heightened analgesic needs in chronic opioid users.
• Chronic opioid use prior to amputation may exacerbate phantom limb pain.