Faculty Bibliography

INTRODUCTION: Severe allergic reactions during anesthesia are rare events (1:6000 to 1:20000) that can be challenging to recognize in the operating room because the hypotensive manifestation often overlaps with the effects of anesthetics.1 Previous studies have shown varying frequencies of agents associated with allergic reactions with neuromuscular blocking drugs most common in European and Australia/New Zealand studies.2,3 However, recent studies in the U.S. have demonstrated that antibiotics are the most frequent cause.^1,4 The purpose of our study was to examine the causes, manifestations, and frequencies of severe allergic reactions during anesthesia at our medical center. METHODS: Quality management data from a university medical center from 2013-5 were reviewed for cases of severe allergic reactions during anesthesia. Medical records of these patients were examined for demographics, suspected causative agent, allergic reaction manifestations, and outcome. Causative agents of these reactions were determined by the clinicians caring for the patient and/or those reviewing the cases. RESULTS: 15 cases of severe allergic reactions during anesthesia were identified from a total of 112,000 (1:7500) cases during the 3-year period (Table 1). Antibiotics were the suspected causative agent in 11 cases (73%). NSAIDs, narcotics, and protamine were responsible for the other allergic reactions. There were no cases of severe allergic reactions to muscle relaxants (Fig. 1). The most frequent manifestations were hypotension and erythema, each presenting in 10 cases (67%) (Fig. 2). Of the reactions that presented intraoperatively, 5 cases were cancelled (33%). In 1 case there was a documented allergy history to medication given. There were no deaths. CONCLUSIONS: This study demonstrates and reaffirms that severe allergic reactions during anesthesia are rare. At our medical center, these reactions were most commonly caused by antibiotics. This is contrary to some studies which show that muscle relaxants are the most frequent cause of significant allergic reactions. Hypotension was one of the most common clinical manifestations. However, clinicians frequently fail to make the diagnosis of allergic reaction because they attribute hypotension to anesthetic effects. Examination of the skin, which is frequently draped for surgery, and finding erythema in combination with hypotension should direct clinicians to the diagnosis of allergic reaction. Severe allergic reactions during anesthesia can be fatal. There were no deaths or serious adverse consequences in our cases because the allergic reactions were discovered and addressed quickly. Vigilance, diagnosis, and prompt definitive treatment can result in excellent outcomes. Future studies should focus on allergy testing for all cases of suspected intraoperative allergic reactions in order to unquestionably establish the identity of the causative agent

ABSTRACT: Simulation-based training is becoming an accepted tool for educating physicians before direct patient care. As ultrasound-guided regional anesthesia (UGRA) becomes a popular method for performing regional blocks, there is a need for learning the technical skills associated with the technique. Although simulator models do exist for learning UGRA, they either contain food and are therefore perishable or are not anatomically based. We developed 3 sonoanatomically based partial-task simulators for learning UGRA: an upper body torso for learning UGRA interscalene and infraclavicular nerve blocks, a femoral manikin for learning UGRA femoral nerve blocks, and a leg model for learning UGRA sciatic nerve blocks in the subgluteal and popliteal areas

Buprenorphine is a partial mu, kappa agonist that has been shown to influence spontaneous behaviour in animals. Previously, we have demonstrated significant differences in the analgesic response to buprenorphine between the August Copenhagen Irish (ACI)/SegHsd and the Brown Norway (BN)/RijHsd inbred rat strains. The purpose of this study was to determine whether these strains also differed in their behavioural response to buprenorphine in order to provide an additional parameter for the genetic analysis and localization of genes involved in this response. Male and female rats of both strains were used (n = 6/strain/sex) for this study. Each rat was subjected, respectively, to three treatment regimens at 15:00 h: (A) unchallenged; (B) intravenous saline; (C) intravenous buprenorphine (0.05 mg/kg) according to a crossover design. The relative duration (s/h) of locomotion, grooming, drinking and eating behaviour was subsequently determined from 15:30 to 07:00 h using the automatic registration system, Laboratory Animal Behaviour Registration and Analysis System(trade mark). Significant strain differences were observed in unchallenged behaviour between the ACI and the BN rats. ACI rats, but not BN rats, responded to buprenorphine treatment with decreased levels of locomotion, drinking and eating behaviour. The same treatment resulted in an increased grooming behaviour in both strains. Slight but significant sex differences were observed for locomotion and eating in the analysis of variance procedure, but did not reach the level of statistical significance in the multiple comparison procedure. The results of this study emphasize the possibility that strain-specific effects must be taken into account when using behavioural parameters for the assessment of the analgesic effects of buprenorphine in rats.