Role of Intrathecal Opioids in Managing Severe Pain

Indications and Patient Selection

The American Society of Clinical Oncology recommends intrathecal opioid delivery for patients with severe, refractory pain who have failed conventional pain management strategies, particularly those with cancer pain or intractable non-cancer pain with life expectancy >6 months 1, 2
Intrathecal opioid administration should be considered in patients experiencing pain in various anatomic locations including head and neck, upper and lower extremities, and trunk 1, 3
Patients with inadequate pain relief despite systemic opioid dose escalation, or non-effective response to opioid switching or route changes, are most appropriate for intrathecal opioid therapy 2, 4
Life expectancy >6 months is a consideration for implantable pump systems 2, 4

Intrathecal route requires only 1/10 of systemic dose for equivalent analgesia, and epidural route requires 20-40% of systemic dose 1, 2
Lower risk of infection compared to epidural route, and fewer catheter problems compared to epidural delivery 1, 2
Delivery options include percutaneous catheters, tunneled catheters, and implantable programmable pumps 1, 2
Fully implanted systems offer less infection risk and lower maintenance requirements but involve more complex positioning 1, 2

Primary medications used intrathecally include morphine, ziconotide, and baclofen (particularly for spasticity) 1, 2, 4
Adjuvant medications include local anesthetics (bupivacaine 0.125%-0.25%) and limited evidence supports subanesthetic doses of ketamine for intractable pain 1, 2, 4

Intrathecal techniques should be included as part of cancer pain management strategy but widespread use should be avoided 1, 2
Intrathecal delivery should be monitored by a skilled team 1, 2, 4