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Background: Large volumes of dilute local anesthesia are increasingly used not only for liposuction but also for other large cutaneous surgeries, including skin cancer excision. Although the lidocaine serum levels and peaks after injection of tumescent anesthesia in the trunk were shown to be safe even when used in high doses, the levels after use of less dilute (1% lidocaine) solutions for facial cancer surgery have not been described. Objective: We sought to ascertain whether perioperative peak lidocaine levels during Mohs micrographic surgery approach thresholds for lidocaine toxicity. Methods: In this prospective cohort study, each Mohs micrographic procedure was commenced per routine protocol, with use of injectable 1% lidocaine with 1:200,000 epinephrine and 1:10 8.4% bicarbonate for local anesthesia. Six peripheral blood draws of 5 mL each were performed and sent for serum lidocaine concentration measurement. Blood draws were obtained before and after the first two stages of Mohs micrographic surgery, and before and after the third stage or wound repair, as appropriate. Subjects and investigators reported any symptoms or signs of lidocaine toxicity. The main outcome measures include: (1) number of subjects exhibiting at least one level higher than the threshold for toxicity; and (2) sustained elevated lidocaine levels in one or more subjects. Results: Mean total lidocaine volume per subject was 15 mL (range: 5-48 mL). The highest peak serum lidocaine level detected at any time point (blood draw) for any subject was 0.3 μg/mL. Mean serum lidocaine level for all 6 time points was less than 0.1 μg/mL and was thus not detected. Detectable lidocaine levels were found to be associated with higher mean (P = .028) and median (P = .008) total lidocaine doses. Because no toxic levels were detected, it was not possible to measure sustained high lidocaine levels. Limitations: Limitations of this study include the lack of use of very concentrated (eg, 2% vs 1%) lidocaine solution. Conclusions: Lidocaine use during Mohs micrographic surgery does not appear to result in serum lidocaine levels approaching toxic levels even when relatively high total lidocaine doses are used. There is an association between higher total lidocaine dose and perioperative peak serum lidocaine level. [Copyright &y& Elsevier]

Context In 1998, a multidisciplinary team of investigators initiated RADAR (Research on Adverse Drug events And Reports), a clinically based postmarketing surveillance program that systematically investigates and disseminates information describing serious and previously unrecognized adverse drug and device reactions (ADRs). Objective To describe the structure, operations, and preliminary findings from the RADAR project and related dissemination efforts by pharmaceutical suppliers and the US Food and Drug Administration (FDA). Design After identifying a serious and unexpected clinical event suitable for further investigation, RADAR collaborators postulated clinical hypotheses and derived case series and incidence estimates from physician queries, published and unpublished clinical trials, published case reports, FDA databases, and manufacturer sales figures. Results RADAR investigators identified 16 types of serious ADRs among 1699 patients, of whom 169 (10%) died as a result of the reaction. Initial cases were identified by 7 RADAR investigators, 4 collaborating physicians, 2 attorneys, and by reviewing 3 published reports. Additional sources included queries of occupational health programs and medical directors of interventional cardiology laboratories (3 types of ADRs), published manuscripts and clinical trials (11 types of ADRs), review of medical records at a RADAR site (2 types of ADRs), unpublished clinical trial reports (3 types of ADRs), and reports from attorneys, family members, or patients (4 types of ADRs). Incidence estimates, ranging from 0.4% to 33%, were derived from 5 clinical trial reports, 2 physician queries, and 2 observational databases. Laboratory support for hypotheses included identification of 3 neutralizing antibodies and 3 histopathological findings. ADR reports were disseminated as 8 revised package inserts, 7 “dear doctor” letters, and 9 peer-reviewed articles. Conclusion A new, clinically based, hypothesis-driven approach to postmarketing surveillance may supplement existing regulatory surveillance systems and improve patient safety. [ABSTRACT FROM AUTHOR]