Bier blocks are used in an upper or lower extremity to help combat complex regional pain syndrome after the diagnosis is made. These blocks are usually placed for complex regional pain syndrome in a hand, arm, foot or leg.
This injection is done in a surgical center. An IV is placed in the extremity that is effected. A second IV in the normal extremity may also be placed. The extremity that is effected will then be wrapped in a plastic bandage to help squeeze the blood out of this extremity and to keep it out a tourniquet is placed in the upper arm or upper leg. Then local anesthetic and possibly a second medication will be injected into the limb. This may or may not anesthetize the limb for the next 15 to 30 minutes depending upon the medication. At this point the tourniquet will be deflated, vital signs will be monitored, and the patient will remain in the surgery center for the next 30 minutes for evaluation.
Potential complications do depend upon the drugs that are used in the injection, which include guanethidine, bretylium, labetalol, prazosin, clonidine and reserpine. Please note that IV guanethidine and reserpine are not readily available in the United States. A mixed alpha or beta antagonist, labetalol, may be used. As above, potential side effects do depend upon the drugs, but can include low blood pressure, dizziness, black out, and transient drop in blood flow to that effected limb called ischemia, which may or may not produce neuropathy. Please note that it is recommend that the patient do not eat or drink for up to four hours prior to this procedure.