Risk of adverse events due to high volumes of local anesthesia during Mohs micrographic surgery

General guidelines for the maximum amounts of locally injected lidocaine exist; however, there is a paucity of data in the Mohs micrographic surgery (MMS) literature. This study aimed to determine the safety and adverse effects seen in patients that receive larger amounts of locally injected lidocaine. A retrospective chart review of 563 patients from 1992 to 2016 who received over 30 mL of locally injected lidocaine was conducted. Patient records were reviewed within seven postoperative days for complications. The average amount of anesthesia received was 40 mL, and the average patient weight was 86.69 kg. 1.4% of patients had a complication on the day of surgery, and 4.4% of patients had a complication within 7 days of the surgery. The most common complications were excessive bleeding/hematoma formation and wound infection. Only two complications could be attributable to local anesthetics. Gender, heart disease, hypertension, diabetes, and smoking were not significant risk factors for the development of complications. MMS is a safe outpatient procedure for patients that require over 30 mL of locally injected anesthesia. The safety of high volumes of lidocaine extends to patients with risk factors such as heart disease, hypertension, diabetes, and smoking.