Brachial plexus block commonly used in finger replantation has the advantages of simple operation, small side effects, and stable circulation, but it has inherent problems such as imperfect block range, slow onset of anesthesia, and short maintenance time of anesthesia. In order to explore the reliable clinical anesthesia effect, this paper uses experimental investigation methods to study the effect of dexmedetomidine in clinical surgery of replantation of severed fingers. Moreover, this paper uses comparative test methods, uses statistical methods to process test data, and uses intuitive methods to display test results. Finally, this paper verifies the reliability of dexmedetomidine in replantation of severed finger through comparative analysis and verifies that the anesthesia method proposed in this paper has certain user satisfaction through parameter survey.