This article is missing citations or needs footnotes. Please help add inline citations to guard against copyright violations and factual inaccuracies. (June 2007)

Bier block anesthesia is an intravenous regional anesthesia technique in which an extremity (generally an arm) is made numb for surgery by injecting a local anesthetic solution into a vein after the blood has been squeezed out of the extremity and a tourniquet has been placed on it. The tourniquet prevents the local from leaving the extremity and blood from entering it, giving the patient a numb (anesthetic) extremity and the surgeon a bloodless field to work in.

The advantages of the technique is that it is simple to perform, and provides a bloodless field that is easy to work in and minimizes blood loss. The disadvantages are that there is a practical time limit on its use (1 - 2 hours) due to the tourniquet restricting blood flow to the extremity. Thus, the tissues of the extremity are not getting oxygen. The extremity could eventually be damaged, and large doses of local anesthetic are required intravenously to produce the numbness. If the tourniquet is released before a large amount of the local anesthetic is metabolized or chemically bound, there is a possibility of a toxic blood level with the attendant problems.

• Intravenous regional anaesthesia (Bier's block) PRACTICAL PROCEDURES Issue 1 (1992) Article 2: Page 1 of 1 Dr W.F. Casey, Consultant Anaesthetist, Gloucestershire Royal Hospital, Gloucester.