Pulse Oximeter Perfusion Index as a Predictor of Successful Supraclavicular Brachial Plexus Block

Abstract

Objective Ultrasound-guided supraclavicular brachial plexus block is a popular anesthetic technique for upper limb surgeries. Assessing the success sensory and motor block using conventional methods is time consuming and also it needs patient co-operation. In the present study, objective method like increase in perfusion index is used to predict the success of ultrasound-guided supraclavicular block. Materials and Methods This prospective trial consists of total 95 patients undergoing elective upper limb procedures. All patients received ultrasound-guided supraclavicular block using 0.5% bupivacaine 20 mL. Sensory and motor blocks were evaluated every 5 minutes followed by pinprick testing and ability to flex the elbow and the hand against gravity, respectively. The perfusion index was measured using pulse oximetry applied on the index finger and recorded at baseline and 10, 20, and 30 minutes interval after local anesthetic injection in both the blocked limb and the contralateral unblocked limb using two separate pulse oximeters. Results Perfusion index increased in blocked arm after 5 minutes compared with unblocked arm and also to its baseline value. Both perfusion index and perfusion index ratio in blocked arm were found statistically significant. Conclusion To evaluate the success of supraclavicular block, perfusion index can be considered as a useful tool.