Michelle K. York

This is the first multi-centre retrospective survey from the United Kingdom to evaluate the aetiology and diagnostic performance of tryptase in anaphylaxis during general anaesthesia (GA). Data were collected retrospectively (2005-12) from 161 patients [mean ± standard deviation (s.d.), 50 ± 15 years] referred to four regional UK centres. Receiver operating characteristic curves (ROC) were constructed to assess the utility of tryptase measurements in the diagnosis of immunoglobulin (Ig)E-mediated anaphylaxis and the performance of percentage change from baseline [percentage change (PC)] and absolute tryptase (AT) quantitation. An IgE-mediated cause was identified in 103 patients (64%); neuromuscular blocking agents (NMBA) constituted the leading cause (38%) followed by antibiotics (8%), patent blue dye (6%), chlorhexidine (5%) and other agents (7%). In contrast to previous reports, latex-induced anaphylaxis was rare (0·6%). A non-IgE-mediated cause was attributed in 10 patients (6%) and no cause could be established in 48 cases (30%). Three serial tryptase measurements were available in 34% of patients and a ROC analysis of area under the curve (AUC) showed comparable performance for PC and AT. A ≥ 80% PPV for identifying an IgE-mediated anaphylaxis was achieved with a PC of >141% or an AT of >15·7 mg/l. NMBAs were the leading cause of anaphylaxis, followed by antibiotics, with latex allergy being uncommon. Chlorhexidine and patent blue dye are emerging important health-care-associated allergens that may lead to anaphylaxis. An elevated acute serum tryptase (PC >141%, AT >15·7 mg/l) is highly predictive of IgE-mediated anaphylaxis, and both methods of interpretation are comparable.

INTRODUCTION: Incidents of bias and microaggressions are prevalent in the clinical setting and are disproportionately experienced by racial minorities, women, and medical students. These incidents contribute to burnout. Published efforts to address these incidents are growing, but gaps remain regarding the long-term efficacy of these curricular models. We developed and longitudinally evaluated a workshop that taught medical students a framework to respond to incidents of bias or microaggressions. METHODS: In October 2019, 102 Vanderbilt core clerkship medical students participated in an hour-long, interactive, case-based workshop centered around the 3 D's response behavior framework: (1) direct, (2) distract, and (3) delegate. Participants were surveyed before and after the training, and both qualitative and quantitative data were collected. A refresher workshop was offered 8 months later, which added two additional D's: delay and display discomfort. RESULTS: After the workshop, respondents' knowledge of the assessed topics improved significantly, as did their confidence in addressing both personally experienced and witnessed incidents. Respondents initially indicated a high likelihood of using response behaviors to address incidents. The workshop did not consistently modify behavioral responses to experienced or witnessed incidents. Ninety-one percent of respondents agreed the workshop was effective. DISCUSSION: This workshop provided an effective curriculum to sustainably improve participant knowledge and confidence in responding to incidents of bias and microaggressions. This resource can be adopted by educators at other institutions.

BACKGROUND: Sheffield NARCOS (National Adverse Reactions Advisory Service) investigates suspected perioperative anaesthetic reactions using serial tryptase, urinary methylhistamine (UMH) and clinical information. Further recommendations for additional allergy clinic assessment are provided. OBJECTIVE: To establish a robustly measurable protocol for identifying mast cell mediator (MMR) release in this cohort. To compare these thresholds with previously suggested thresholds and algorithms. METHOD: A review of 3455 NARCOS cases referred with a suspected perioperative allergic reaction. Tryptase, UMH and clinical details were analysed. A total of 1746 cases were graded using the Ring and Messmer scale. Reaction grade, tryptase and UMH changes were compared with statistical and graphical presentations appropriate to non-normally distributed measurements using Analyse-IT software. RESULTS: Sensitive strategies such as 3 μg/L or 20% are measurable and translatable and would substantially increase detection of potentially relevant changes in tryptases. Adequate quality assurance for low-level measurement is needed. An incremental threshold of 20% would identify potential MMR in an additional 14% of cases with peak tryptase (Tp) between 5 and 14 μg/L and a further 15% with Tp below 5 μg/L. Further work is required to establish the diagnostic performance characteristics of this more sensitive approach. UMH also identified up to 120 further cases of potential MMR in the absence of tryptase increments. CONCLUSIONS AND CLINICAL RELEVANCE: Future studies should establish and compare the predictive performance characteristics of each strategy against clinical phenotypes. A single agreed definition of positive serial tryptases is needed to enable robust evaluation of diagnostic strategies. This could serve as a harmonized standard for comparative studies of case series from different centres.