Nerve blocks in palliative care.

Although between 85% and 90% of patients with advanced cancer can have their pain well controlled with the use of analgesic drugs and adjuvants, there are some patients who will benefit from an interventional procedure. This includes a variety of nerve blocks and also some neurosurgical procedures. Approximately 8-10% of patients may benefit from a peripheral nerve block and around 2% from a central neuraxial block. The most common indication is because opioid dose escalation is limited by signs of opioid toxicity but some patients will benefit from one component of their pain being relieved by a simple peripheral block. Most patients about to undergo these procedures are already taking high doses of opiods and obtaining valid consent may pose problems. The use of peripheral nerve blocks, epidural and intrathecal infusions, and plexus blocks is discussed.