Bier block /bēr blok/ [August Karl Gustav Bier, German surgeon, 1861–1949] , regional anesthesia accomplished after intravenous injection of an exsanguinated extremity with a preservative-free local anesthetic such as 0.5% lidocaine. Used for surgical procedures on the arm below the elbow or the leg below the knee. A Bier block is performed by first inserting an intravenous catheter and then connecting a saline-flushed port, such as a hep-lock. The affected extremity is then sequentially and tightly wrapped with an Esmarch’s bandage to exsanguinate the extremity. A pneumatic double tourniquet, placed proximal to the elbow or knee is then inflated to a pressure that is 100 torr (mm Hg) greater than the systolic blood pressure. The local anesthetic is then injected intravenously, while the double tourniquet prevents the local anesthetic from entering the systemic circulation. A Bier block is limited to procedures of short duration (less than 1 hour). See also anesthesia, regional anesthesia.
