Key points
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Intravenous (IV) regional anesthesia is usually achieved using dilute lidocaine 0.5%; 50 mL of prilocaine has also been used successfully.
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The IV regional block is useful for procedures lasting 90–120 minutes. This time limit is due to tourniquet time constraints rather than to diminution of the local anesthetic effect.
Perspective
IV regional anesthesia was introduced by Bier in 1908. As illustrated in Fig. 11.1 , in the initial description, a surgical procedure was required to cannulate a vein, and both proximal and distal tourniquets were used to contain the local anesthetic in the venous system. After its introduction, the technique fell into disuse until the less toxic amino amides became available in the mid-20th century. This technique can be used for a variety of upper extremity operations, including both soft tissue and orthopedic procedures, primarily in the hand and forearm. The technique has also been used for foot procedures with a calf tourniquet.
Patient Selection. The technique is best suited for patients in whom there is no disruption of the venous system of the involved upper extremity, because the technique relies on an intact venous system. It can be used for distal orthopedic fractures and soft tissue operations. Intravenous regional block may not be appropriate for patients in whom movement of the upper extremity causes significant pain, because movement of the upper extremity is required to exsanguinate blood from the venous system adequately.
Pharmacologic Choice. The most commonly used agent for IV regional anesthesia is a dilute concentration of lidocaine; however, prilocaine has also been used successfully. Lidocaine is used in a 0.5% concentration; approximately 50 mL is used for an upper extremity IV regional block.
Placement
Anatomy. The only anatomic detail necessary for clinical use of the IV regional block is identification of a peripheral vein; one must be cannulated in the involved extremity.
Position. The patient should be resting supine on the operating table with an IV tube already established in the nonsurgical arm. The involved arm should be extended on an armboard near available supplies ( Fig. 11.2 ).
