Lumbar Sympathetic Block

What is lumbar sympathetic block?

A lumbar sympathetic block is the injection of medication into the sympathetic nervous system at the lumbar level.

What is the sympathetic nervous system?

The sympathetic nervous system is responsible for the body's response during the times of stress or danger.  For example, sympathetic nerves cause the heart to beat faster and adrenaline to be secreted in preparation for our response to a stressful situation.  In addition, sympathetic nervous impulses cause the constriction of peripheral blood vessels (those in arms and legs).

How are sympathethic nerves involved with pain?

Sometimes a sympathetic nerve may be unnecessarily stimulated as a result of injury or other trauma to the body.  In this situation, the involved sympathetic nerve will cause the blood vessels in the arm or leg to constrict and remain constricted, resulting in poor circulation to that limb.  The patient may then experience pain and possibly swelling, skin and nail changes, unusual color of the skin and temperature changes in the limb.  By blocking the sympathetic nerve impulses, the blood vessels widen, circulation is improved and pain relief may then result.

What conditions are treated with sympathetic blocks?

The most commonly treated condition is Complex Regional Pain Syndrome (CRPS) or Reflex Sympathetic Dystrophy (RSD).  These blocks are also used in situations in which increased circulation to the limb will be beneficial for healing as in diabetic neuropathy or slow healing wounds.

What will happen to me during the procedure?

An IV will be started so that the relaxation medicine can be given. After lying on the X-ray table, the skin over your back will be well cleansed.  Next, the physician will numb a small area of the skin with numbing medicine (anesthetic) which stings for a few seconds.  The physician will then use X-ray guidance to direct a small needle to the correct level in the lumbar sympathetic chain.  When the physician is satisfied with needle placement, medication (local anesthetic) will be injected.  The temperature in your foot/leg will be monitored.  A rise in temperature indicates a successful sympathetic block.

What should I do and expect after the procedure?

After the lumbar sympathetic block, the temperature in your foot/leg should increase.  You will notice that your lower leg becomes rosy in color, feels warm and the veins in the leg are "full."  Most importantly, your pain may be decreased.  On occasion, you may experience weakness and/or numbness in the leg or dizziness.  This side effect is temporary.  You may have some soreness at the needle site in your back.  Ice will be typically more helpful than heat for the first 2-3 days after the injection.  You may resume your normal activities on the following day.