Aim: The aim of this study was to optimize the dose of local anesthetic with interscalene-infraclavicular brachial plexus block. Methods: In this retrospective study, an examination was made of the records and peripheral block monitoring forms of 55 patients who underwent humerus surgery under the combined interscalene and infraclavicular block necessary for whole arm surgical anesthesia in the Orthopaedics Clinic between 2015 and 2017. Postoperative analgesia was evaluated and recorded with a visual analog scale (VAS) from 0-10 (0 = no pain, 10 = the most severe pain) every hour in the first 12 hours and at every 4 hours between 12 and 24 hours. The duration of the procedure, the onset of the block, and the duration of the analgesia were recorded. The local anesthetic doses used in the peripheral block procedure were: Group A: interscalene block 15 ml (10 ml 0.5% Bupivacaine + 5 ml 2% Lidocaine) + infraclavicular block 15 ml (10 ml 0.5% Bupivacaine + 5 ml 2% Lidocaine); Group B: interscalene block 10 ml (10 ml 0.5% Bupivacaine + 5 ml 2% Lidocaine) + infraclavicular block 15 ml (10 ml 0.5% Bupivacaine + 5 ml 2% Lidocaine). Results: A statistically significant difference was determined between the two groups in terms of the first analgesia requirement time. The first analgesia requirement time was significantly longer in Group A (P = 0.004). In Group A, patient satisfaction was statistically significantly higher (P = 0.003). Conclusion: Using lower doses of local anesthetic in combined brachial plexus block under USG guidance, sufficient anesthesia can be obtained. In patients with comorbidities in particular, interscalene block + infraclavicular block under USG guidance can be used as an alternative to general anesthesia in surgical interventions involving the whole arm.