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What is it?                

Peripheral nerve block is a treatment used to block pain transmission through the nervous system. It involves intravenous painkillers to supress pain impulses. This treatment is mainly used for treating specific peripheral nerves.         

The procedure is normally done under fluoroscopy (real time X-ray images) or a CT scan (computerised tomography) which enables the doctor to place the injection in the right place. The results from this procedure tend to be immediate, but they are not long lasting. Some patients may need several sessions before noticing an improvement, depending on the severity of each case.

Why would you do it?

A peripheral nerve block is used to treat pain during surgery and while the wounds from it improve.  

Patients who have this kind of pain, whether chronic or not, can be given a nerve block injection to get pain relief, even if it is temporary. 

The pain quite often is located in or radiates from the spine, although there are other areas that are quite frequently affected too, such as the upper and lower limbs, the neck, or the upper part of the buttocks.  

What does it involve?    

Using a peripheral nerve block gives the affected nerve the needed time to recover from the irritant. It can also give the specialist diagnostic information.   

The procedure is normally done on an outpatient basis with no need for hospitalisation. It normally takes between 15 minutes to half an hour to perform. 

The patient will wait on a stretcher so that the doctor has access to the area to be treated. The doctor will use image guidance to locate the exact area. The needle is placed at a specified depth that is closest to the nerve.  

If the injection is to be placed close to a major nerve or set of nerves, such as the sciatic nerve, then the specialist will tell the patient to inform the team if they feel a sudden pain. This indicates that the needle is too close to the nerve and should be relocated.

In some cases, more than one injection is needed, this depends on the number of areas of pain or the size of the area to be treated.  

After the injection, the patient will feel immediate pain relief in the area treated.

How to prepare for it          

No special preparation is generally needed before a peripheral nerve block. A physical examination, previous anaesthetic information, and the patients clinical history is normally enough.

After the procedure the patient may need someone to escort them home. Doctors may request the patient not to eat or drink for at least twelve hours.    

Post-operative care 

The patient may notice numbness in their limb, or a tingling feeling or heaviness.

The specialist can prescribe additional medications to help alleviate pain in other parts of the body.   

Alternative treatments

There are many alternatives for pain relief:

• Pain physiotherapy
• Narcotic (opioid) and non-narcotic painkillers
• Nerve stimulation
• Surgery to relieve pain