Usage of Epinephrine Mixed With Lidocaine in Plastic Surgery

Abstract Plastic surgeons commonly administer subcutaneous epinephrine to reduce intraoperative blood loss. The authors hypothesized that there are safe and effective concentration of epinephrine for vasoconstriction and their durations. The aim of this study is to summarize the existing literatures for the usage of epinephrine mixed with lidocaine in plastic surgical field. In 1903, Braun reported that adrenaline prolonged the local anesthetic effects of cocaine. The Parke-Davis Company began selling cocaine with adrenaline, as well as combining adrenaline with new synthetic local anesthetics. Based on a review of the literature, concentrations between 1:50,000 and 1:400,000 are equally effective and provide superior vasoconstriction compared with more dilute solutions. If epinephrine is further diluted, its onset and time to peak serum concentration are delayed, and its duration of action is shortened. When lidocaine is used without epinephrine, duration of anesthesia is shortened reverse proportionally to the lidocaine concentration. When lidocaine is used with epinephrine, duration of anesthesia is prolonged proportionally to the lidocaine concentration. With slow injection rate in the soft tissue, the maximum safe dose of lidocaine is approximately 3 mg/kg plain and 7 mg/kg when mixed with epinephrine. Lidocaine may protect the myocardium because of its antiarrhythmic activity, which is the rationale for infiltrating lidocaine mixed with epinephrine in general anesthesia. In plastic surgery, subcutaneous infiltration of epinephrine-lidocaine solution is performed to reduce intraoperative blood loss. Even in general anesthesia, infiltrating lidocaine mixed with epinephrine may protect the myocardium because of its antiarrhythmic activity.