LAUSR

Patients with implanted pacemaker underwent upper limb surgery under regional anesthesia in the literature are rarely. We report a case of successful retroclavicular approach to infraclavicular brachial plexus block (RA-IBPB) in a patient with implanted pacemaker andwith requiring open osteosynthesis due to distal radius fracture. The patient who was a 31 year old man was admitted to emergency department with complaint of left wrist pain 1 h after a history of falling. His medical history included that a pacemaker (Medtronic, Minneapolis, USA) had been implanted 2 years ago in the left pectoral area because he was suffering from symptomatic sinus bradycardia. Plain radiographs showed a displaced, dorsally angulated fracture of distal radius. Surgery under regional anesthesia was planned. Informed written consent was obtained from the patient. In the operating room, the patient was placed in a supine position, arm was adducted and head was rotated to contralateral side of the blockade. A 10 MHz linear probe (5–10 MHz Mindray 7L4A, Mindray Bio-Medical Electronics Co, Shenzhen, China) with a sterile cover was placed parasagittally just medial to the coracoid process and caudal from the clavicle (Fig. 1A). At the US imaging, a dense shadow casting from the pacemaker hid the lateral of the axillary artery and lateral cord of the brachial plexus (Fig. 1B). A 21-gauge 100 mm needle was inserted immediately above the clavicle in the space between coracoid process and clavicle, and advanced from cephalad to caudal. After crossed the blind zone, needle was advanced toward the neurovascular bundle. 20ml bupivacaine 0.5%was injected to 6-o'clock position of the axillary artery. Then, the needle was withdrawn to 7 o'clock position and 5 ml 0.5% bupivacaine was injected to guarantee the covered of the lateral cord. Twenty minutes after receiving the block, sensorial and motor blockade were present in left arm. The surgery was lasted for 70 min uneventfully. In this case report, implanted pacemaker in the left pectoral areawas a limiting factor of the needle orientation.We preferred the RA-IBPB because the lateral of the axillary artery and lateral cord of brachial plexus could not precisely identified at the US imaging. In the traditional USguided IBPB (T-IBPB), needle path is the cephaloanterior aspect of the axillary artery, and lateral cord is located at this region. Therefore,