A peripheral nerve block involves the injection of local anaesthetic near the nerves supplying the site of surgery. Your anaesthetist may use an ultrasound machine or another nerve localisation device to carefully guide placement of this medicine. Peripheral nerve blockade renders the parts of the body controlled by these nerves numb and weak. This local anaesthetic effect may last for up to 12 to 18 hours. You may be offered a peripheral nerve block as your sole anaesthetic technique or for postoperative pain relief. If it is used as the main anaesthetic technique, your anaesthetist may administer some sedation to your added comfort.
There are several potential advantages to this type of anesthesia. The local anesthetic can last up to 24 hours, providing long-lasting pain relief for painful procedures. There is less risk of nausea than with general anesthesia. There is also less risk of temporary cognitive dysfunction (confusion), a potential problem in the elderly. There are also some specific risks to peripheral nerve blocks, including:
- Failure (you may be offered an additional or alternative block)
- Insufficient nerve block (you may be offered an additional or alternative block)
- Minor nerve injury (this often resolves within days)
- Major nerve injury (this may be permanent but is extremely rare)
- Damage to other local structures (such as nerves, muscles, blood vessels or organs)
- Drug reaction or toxicity
Your anaesthetist will discuss your individual risks with you. We encourage you to raise your specific questions and concerns with them prior to your procedure.