Comparative epidemiology of suspected perioperative hypersensitivity reactions

Drug challenge testing: a critical step in the investigation of neuromuscular blocking agent hypersensitivity

Neuromuscular blocking agents are a common cause of perioperative hypersensitivity. The sensitivity and specificity of skin tests and in vitro tests in this context have not been determined conclusively, which poses a barrier to accurate diagnosis. Use of challenge testing represents a promising development in this field and a key tool in confirming tolerance to an alternate neuromuscular blocking agent for use in future anaesthesia. However, its use is currently limited to specialised centres, and a standardised approach to testing has not yet been established. This article summarises the role of challenge testing to neuromuscular blocking agents and highlights the advantages and disadvantages of the different approaches.

Exploring the Landscape of Perioperative Immediate Hypersensitivity: A Comprehensive 6-Year Monocentric Observational Analysis on Epidemiology and Risk Factors

INTRODUCTION

Perioperative immediate hypersensitivity (POH) is a rare complication estimated at 1/10,000 anaesthesia. The objective of our study was to investigate the risk factors of POH over a 6-year period in a French teaching hospital.

MATERIALS AND METHODS

A single-centre retrospective descriptive epidemiological study of patients treated in the operating room from January 2016 to December 2021 with and without POH.

RESULTS

111 POH were identified out of 47,585 surgeries, mainly women (71%) with a history of asthma (16% vs. 6%, p < 0.001) undergoing plastic surgery (49% vs. 32%, p < 0.001). POH patients were more likely to receive neuromuscular blocking agents and antibiotics (respectively, 88% vs. 59%, p < 0.001 and 59% vs. 24%, p < 0.001). 92% of patients underwent intraoperative sampling, only 31% benefited from an allergy consultation. 14% had positive skin test (ST). The culprit agent were neuromuscular blocking agents (47% of which 57% rocuronium, 29% suxamethonium, and 14% atracurium), antibiotics (33%, of which 80% cefazolin and 20% cefoxitin), and gelatin (7%).

CONCLUSION

Our study reported a POH incidence of 23/10,000 anaesthesia, with identified allergens aligning with existing literature. These findings underscore the critical need for enhanced patient follow-up to monitor potential hypersensitivity and mitigate future risks.

Preoperative survey to evaluate the patients' allergy list and its relevance to perioperative care

INTRODUCTION

Perioperative hypersensitivity and allergic reactions can result in significant morbidity and mortality. For routine anesthetic care, allergies are determined from a review of the electronic medical record supplemented by a detailed patient history. Although the electronic medical record is generally assumed to be accurate, it may be that allergies are erroneously listed or not based on sound medical practice. The purpose of the current study is to evaluate allergies listed in the electronic medical record of children presenting for surgery and determine their origin, authenticity, and impact on perioperative care.

METHODS

Eligible patients included those presenting for a surgical procedure in the main operating room, who were ≤ 21 years of age, with a drug allergy listed on the EMR. Prior to intraoperative care, an electronic survey questionnaire containing questions related to medication allergies was provided to a guardian or parent. Two anesthesiology physicians reviewed the survey responses to determine the validity of any reported allergies. A second electronic survey was given postoperatively to the attending anesthesiologist to determine whether the documented allergy impacted anesthetic care.

RESULTS

The study cohort included 250 patients, ranging in age from 5 to 14 years (median age 9 years). All of the patients had at least one allergy listed on the electronic medical record. Seventy of the 250 patients (28%) had more than one drug allergy listed for a total of 351 medication allergies. The majority of the listed allergies were related to antibiotics including 155 (44%) from the penicillin family, 26 (7%) cephalosporins, 16 (5%) sulfonamides, and 36 (10%) other antimicrobial agents. Other commonly listed allergies were 27 (8%) nonsteroidal anti-inflammatory agents and 15 (4%) opioids. The remaining 76 (22%) included a miscellaneous list of other medications. On further review of the allergies, the survey was completed for 301 medications. After physician review, 135 of 301 (45%) responses were considered consistent with IgE reactions "true allergy," 73 (24%) were deemed less relevant to IgE reactions "unlikely true allergy," and 93 (31%) were not related to IgE reactions "not an allergy." Care alterations during surgery were uncommon regardless of whether the issue was assessed as a true allergy (11%), unlikely to be a true allergy (3%), or not a true allergy (13%).

CONCLUSION

A significant portion of the documented allergies in children are not true allergies, but rather recognized adverse effects (apnea from an opioid, renal failure from an NSAIDs) or other nonallergic concerns (gastrointestinal upset such as nausea). Erroneously listed allergies may lead to unnecessary alterations in patient care during perioperative care. A careful analysis of the allergy list on the EMR should be supplemented by a thorough patient history with specific questions related to the drug allergy. Once this is accomplished, the allergy listed should be updated to avoid its erroneous impact on perioperative care.

Rocuronium-specific antibodies drive perioperative anaphylaxis but can also function as reversal agents in preclinical models

Neuromuscular blocking agents (NMBAs) relax skeletal muscles to facilitate surgeries and ease intubation but can lead to adverse reactions, including complications because of postoperative residual neuromuscular blockade (rNMB) and, in rare cases, anaphylaxis. Both adverse reactions vary between types of NMBAs, with rocuronium, a widely used nondepolarizing NMBA, inducing one of the longest rNMB durations and highest anaphylaxis incidences. rNMB induced by rocuronium can be reversed by the synthetic γ-cyclodextrin sugammadex. However, in rare cases, sugammadex can provoke anaphylaxis. Thus, additional therapeutic options are needed. Rocuronium-induced anaphylaxis is proposed to rely on preexisting rocuronium-binding antibodies. To understand the pathogenesis of rocuronium-induced anaphylaxis and to identify potential therapeutics, we investigated the memory B cell antibody repertoire of patients with suspected hypersensitivity to rocuronium. We identified polyclonal antibody repertoires with a high diversity among V(D)J genes without evidence of clonal groups. When recombinantly expressed, these antibodies demonstrated specificity and low affinity for rocuronium without cross-reactivity for other NMBAs. Moreover, when these antibodies were expressed as human immunoglobulin E (IgE), they triggered human mast cell activation and passive systemic anaphylaxis in transgenic mice, although their affinities were insufficient to serve as reversal agents. Rocuronium-specific, high-affinity antibodies were thus isolated from rocuronium-immunized mice. The highest-affinity antibody was able to reverse rocuronium-induced neuromuscular blockade in nonhuman primates with kinetics comparable to that of sugammadex. Together, these data support the hypothesis that antibodies cause anaphylactic reactions to rocuronium and pave the way for improved diagnostics and neuromuscular blockade reversal agents.

Incidence of and risk factors for paediatric perioperative anaphylaxis in the USA

BACKGROUND

Perioperative anaphylaxis is a serious and often life-threatening immediate hypersensitivity reaction. There are few published data on paediatric perioperative anaphylaxis (pPOA). We evaluated the incidence of and risk factors involved in the occurrence of pPOA within a large US national database.

METHODS

Deidentified data from the US Nationwide Inpatient Sample from 2005 to 2014 were used to identify pPOA cases and to conduct a retrospective multivariate analysis of preselected independent variables.

RESULTS

Among 3,601,180 surgeries and procedures in children aged 0-18 yr, 297 pPOA cases were identified for an incidence of one in 12,125 surgeries and procedures. Compared with controls, pPOA cases had an increased median length of stay (6 vs 2 days; P<0.001) and median hospital cost ($54 719 vs $5109; P<0.0001). The age groups between 6 and 12 yr (odds ratio [OR] 7.1; 95% confidence interval [CI] 3.9-12.9; P<0.001) and 13 and 17 yr (OR 8.5; 95% CI 4.7-15.2; P<0.001) were associated with increased odds of pPOA. Transplant (OR 46.3; 95% CI 20.8-102.9; P<0.001), cardiac (OR 16.4; 95% CI 7.5-35.9; P<0.001), and vascular (OR 15.2; 95% CI 7.5-30.7; P<0.001) procedures posed the highest risk for pPOA. Chronic pulmonary disease, coagulopathy, and fluid and electrolyte disorders were also associated with pPOA (OR 2.2; 95% CI 1.5-3.3; P<0.001).

CONCLUSIONS

The incidence of pPOA was one in 12,125 cases. Risk factors included age, procedure type, and comorbidities.

Management and treatment of perioperative hypersensitivity

PURPOSE OF REVIEW

Perioperative hypersensitivity reactions are rare but potentially catastrophic events. This review acts to summarize recent recommendations for both immediate and poststabilization management of suspected reactions, alongside practical advice for anaesthetists who may be faced with these events.

RECENT FINDINGS

Prompt treatment is essential but may be hampered by delay in recognition. This can occur because there are multiple differential diagnoses for the observed clinical signs as well as variations in clinical presentation. Resuscitation is dependent on the use of adrenaline and fluids. Adrenaline should be administered in small, titrated intravenous boluses. Low-dose infusions should be commenced early if the response to boluses is poor. Large volume fluid resuscitation may be required to maintain adequate circulating volume. Chest compressions are recommended when there is evidence of inadequate perfusion, rather than waiting until cardiac arrest is confirmed. Antihistamines and corticosteroids are no longer recommended in the immediate management phase. Once the patient has been stabilized, it is important to obtain serial tryptase concentrations to aid the subsequent clinic investigation. The decision to proceed or abandon surgery will be based on an individual risk-benefit analysis. All cases of suspected perioperative hypersensitivity, including fatal cases, must be referred for formal investigation.

SUMMARY

There have been recent updates to management guidelines in perioperative hypersensitivity. Treatment algorithms, treatment packs and referral packs can all help the anaesthetist manage these complex cases, aid the subsequent investigation and ensure patient safety in the future.

Remimazolam-Induced Anaphylaxis and Cardiovascular Collapse: A Narrative Systematic Review of Eleven Cases

Background and Objectives: Remimazolam, a novel benzodiazepine, is used for procedural sedation and general anesthesia due to its rapid onset and short duration of action. However, remimazolam-induced anaphylaxis (RIA) is a rare but severe complication. This study aimed to analyze RIA characteristics, focusing on cardiovascular collapse, and provide guidelines for safe remimazolam use. Methods: This study conducted a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Research articles retrieved from PubMed on 26 May 2023, using the keywords 'remimazolam AND anaphylaxis' were evaluated based on the inclusion criteria of being written in English and aligning with the World Allergy Organization criteria for anaphylaxis, while studies not meeting these criteria were excluded. All published articles up to the search date were included without any date restrictions. The review analyzed factors such as age, sex, type of anesthesia, remimazolam dose (bolus/continuous), allergic symptoms and sign, epinephrine use, serum tryptase levels, and skin prick tests. Results: Among eleven cases, the mean age was 55.6 ± 19.6 years, with 81.8% male. Hypotension (81.8%) was the most common symptom, followed by bradycardia (54.5%) and desaturation (36.4%). Two patients experienced cardiac arrest. Serum tryptase levels confirmed anaphylaxis in ten cases. Epinephrine was the primary treatment, with intravenous doses ranging from 0.1 mg to 0.3 mg. Conclusions: Vigilance is crucial when administering remimazolam, adhering to recommended dosages, and promptly treating RIA with epinephrine. Further research is needed to understand the risk factors and refine the management strategies. Guidelines for safe remimazolam use are proposed.

Evaluation of the passive mast cell activation test for identifying allergens in perioperative anaphylaxis: a study protocol for a prospective diagnostic accuracy study

INTRODUCTION

Perioperative anaphylaxis (POA) can lead to significant complications. Therefore, accurate identification of allergens for POA patients is critical to ensure the safety of future surgical and anaesthetic procedures. Existing perioperative allergen detection methods face challenges in sensitivity and specificity. The passive mast cell activation test (pMAT) has recently emerged as a potential diagnostic tool. Our study aims to evaluate the diagnostic efficacy of pMAT for identifying perioperative allergens, with a focus on non-depolarising neuromuscular blocking agents, the most common culprits of POA.

METHODS AND ANALYSIS

This prospective diagnostic accuracy study will measure the diagnostic accuracy of pMAT in POA patients. Participants will undergo skin testing (ST), basophil activation testing (BAT) and pMAT. The diagnostic validity of pMAT will be assessed based on the results of ST and BAT. The assessment of diagnostic accuracy will include sensitivity, specificity, likelihood ratios, and false-positive and false-negative rates while measurement of the consistency rate will assess reliability.

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board of China-Japan Friendship Hospital (2023-KY-247). Results will be disseminated through academic presentations and peer-reviewed journal publications and will provide valuable scientific data and some new insights into the diagnostic accuracy of pMAT.

Examining cefazolin utilization and perioperative anaphylaxis in patients with and without a penicillin allergy label: A cross-sectional study

STUDY OBJECTIVE

To compare the occurrence of cefazolin perioperative anaphylaxis (POA) in patients with and without a penicillin allergy label (PAL) to determine whether the prevalence of cefazolin POA differs based on the presence of a PAL.

DESIGN

Cross-sectional study.

SETTING

A large U.S. healthcare system in the Baltimore-D.C. region, July 2017 to July 2020.

PATIENTS

112,817 surgical encounters across inpatient and outpatient settings in various specialties, involving 90,089 patients. Of these, 4876 (4.3%) encounters had a PAL.

INTERVENTIONS

Perioperative cefazolin administration within 4 h before surgery to 4 h after the procedure began.

MEASUREMENTS

The primary outcome was cefazolin POA in patients with and without PALs. Potential POA cases were identified based on tryptase orders or diphenhydramine administrations within the initial cefazolin administration to 6 h postoperatively. Verification included two validation steps. The first checked for hypersensitivity reaction (HSR) documentation, and the second, led by Allergy specialists, identified POA and the probable culprit. The secondary outcome looked at cefazolin use trends in patients with a PAL, stratified by setting and specialty.

MAIN RESULTS

Of 112,817 encounters, 1421 (1.3%) had possible cefazolin HSRs. Of these, 22 (1.5%) had POA, resulting in a 0.02% prevalence. Of these, 13 (59.1%) were linked to cefazolin and 9 (40.9%) attributed to other drugs. Only one cefazolin POA case had a PAL, indicating no significant difference in cefazolin POA prevalence between patients with and without PALs (p = 0.437). Perioperative cefazolin use in patients with PALs steadily increased from 2.6% to 6.0% between 2017 and 2020, specifically in academic settings.

CONCLUSIONS

The prevalence of cefazolin POA does not exhibit significant differences between patients with and without PALs, and notably, the incidence remains remarkably low. Based on these findings, it is advisable to view cefazolin as an acceptable choice for prophylaxis in patients carrying a PAL.

Relationship between perioperative anaphylaxis and history of allergies or allergic diseases: A systematic review and meta-analysis with meta-regression

STUDY OBJECTIVE

We conducted this meta-analysis to summarize the available evidence and evaluate the relationship between a history of allergies/allergic diseases and perioperative anaphylaxis to offer preventive decision support.

DESIGN

Systematic review and meta-analysis of observational studies.

SETTING

We searched the MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials databases for observational studies. Two investigators independently performed the search, screened the articles, and collected the study details.

MEASUREMENTS

Several databases were systematically searched to evaluate the relationship between a history of allergies/allergic diseases and perioperative anaphylaxis using subgroup analysis, sensitivity analysis and meta-regression.

MAIN RESULTS

A total of 19 studies involving 672 anaphylaxis episodes, 5608 immune-mediated reactions, and 1126 severe episodes met the eligibility criteria and were included in this meta-analysis. Drug allergies, food allergies, a history of allergies, and atopy increased the incidence of perioperative anaphylaxis (Drug allergies, odds ratio [OR] 3.54, 95% confidence interval [CI] 1.07-11.69; Food allergies, OR 2.29, 95% CI 1.23-4.26; A history of allergies, OR 4.86, 95% CI 3.65-6.49; Atopy, OR 3.58, 95% CI 1.47-8.71), but not the presence of immune-mediated reactions and the severity of perioperative anaphylaxis.

CONCLUSIONS

Patients with previous drug allergies, food allergies, a history of allergies, or atopy are more likely to develop anaphylaxis during the perioperative period. Additional studies should be carried out to determine whether a history of allergies/allergic diseases is a major factor for perioperative anaphylaxis when confounders are controlled.

Epidemiology of perioperative anaphylaxis in France in 2017-2018: the 11th GERAP survey

BACKGROUND

Perioperative anaphylaxis is rare but is associated with significant morbidity. This complication has been well described in France by the GERAP (Groupe d'Etude des Réactions Anaphylactiques Périopératoires), a network focused on its study. The epidemiology of perioperative anaphylaxis is evolving, influenced by environmental factors and clinical practice. The aim of this study was to update the epidemiology of perioperative anaphylaxis in France.

METHODS

This multicentre retrospective study was performed in 26 allergy clinics of the GERAP network in 2017-8.

RESULTS

There were 765 patients with perioperative anaphylaxis included. Most cases were severe, with 428 (56%) reactions graded as 3 or 4 according to the Ring and Messmer classification. Skin test results were available for 676 patients, with a culprit agent identified in 471 cases (70%). Neuromuscular blocking agents were the main cause of perioperative anaphylaxis (n=281; 60%), followed by antibiotics (n=118; 25%) and patent blue dye (n=11; 2%). Cefazolin was the main antibiotic responsible for perioperative anaphylaxis (52% of antibiotic-related reactions). Suxamethonium and rocuronium were the main neuromuscular blocking agents responsible for perioperative anaphylaxis with 7.1 (6.1-8.4) and 5.6 (4.2-7.4) reactions per 100,000 vials sold, respectively, whereas cefazolin-related cases were estimated at 0.7 (0.5-0.9) reactions per 100,000 vials sold.

CONCLUSIONS

Our results confirm that most commonly identified triggering agents remain neuromuscular blocking agents. Reactions to antibiotics, particularly cefazolin, are becoming increasingly frequent. The origin of sensitisation to cefazolin is unknown, as no cross-sensitisation has been described, and it should be the subject of further study. Perioperative anaphylaxis should be followed over the years and understood given the changing triggers.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (NCT04654923).

A US-Based Multicenter Retrospective Report of Perioperative Anaphylaxis, 2010-2021

BACKGROUND

US-based perioperative anaphylaxis (POA) studies are limited to single-center experiences. A recent report found that a serum acute tryptase (sAT) >9.8 ng/mL or mast cell activation (MCA) can predict POA causal agent identification. Urinary mast cell mediator metabolites (uMC) have not been studied in POA.

OBJECTIVE

To analyze the epidemiologic data of POA, to determine if sAT or MCA can predict suspected causal agent identification, and to evaluate uMC utility in POA.

METHODS

This study is a retrospective multicenter review of POA cases that were subcategorized by suspected causal agent identification status. sAT, MCA (defined as sAT >2 + 1.2 × serum baseline tryptase), and uMC (N-methylhistamine [N-MH], 11β-prostaglandin-F2α [11β-PGF2α], leukotriene E4 [LTE4]) were recorded.

RESULTS

Of 100 patients (mean age 52 [standard deviation 17] years, 94% adult, 50% female, 90% White, and 2% Hispanic) with POA, 73% had an sAT available, 41% had MCA, 16% had uMC available, and 50% had an identifiable suspected cause. POA cases with an identifiable suspected cause had a positive MCA status (100% vs 78%; P = .01) compared with POA with an unidentifiable cause. An elevated median sAT did not predict causal agent identification. Positive uMC were not associated with suspected causal agent identification during POA. Patients with positive uMC had a higher median sAT (30 vs 6.45 ng/mL; P = .001) and MCA status (96% vs 12%; P = .001) compared with negative uMC patients. Patients with POA had an elevated acute/baseline uMC ratios: 11β-PGF2α ratio > 1.6, N-MH ratio >1.7, and LTE4 ratio >1.8.

CONCLUSIONS

The presence of MCA in POA is associated with suspected causal agent identification. Positive uMC possibly correlate with a higher sAT level and MCA status but require further study. The authors suggest applying an acute/baseline uMC ratio (11β-PGF2α ratio >1.6, N-MH ratio >1.7, and LTE4 ratio >1.87) in patients with POA for MCA when a tryptase level is inconclusive during POA evaluations.

Emergency treatment of peri-operative anaphylaxis: Resuscitation Council UK algorithm for anaesthetists

Peri-operative anaphylaxis is a rare but potentially catastrophic event which must be considered whenever unexpected and significant cardiovascular or respiratory compromise occurs during anaesthesia. The Resuscitation Council UK algorithm for peri-operative anaphylaxis highlights the importance of early intravenous adrenaline and fluid resuscitation and provides guidance on the treatment of refractory anaphylaxis and immediate follow-up. This algorithm is endorsed by the Royal College of Anaesthetists, Association of Anaesthetists, British Society of Allergy and Clinical Immunology and Clinical Immunology Professional Network of the British Society for Immunology. This document was produced by the Perioperative Allergy Network steering committee in collaboration with the Resuscitation Council UK.

Pholcodine and allergy to neuromuscular blocking agents: where are we and how did we get here?

Despite the purported link between pholcodine and neuromuscular blocking agent allergy, screening for prior pholcodine use offers no practical benefit to patients, and anaesthetists should continue to use a neuromuscular blocking agent where this is clinically indicated.

Changing patterns in the epidemiology of drug allergy

Drug allergy (DA) remains a complex and unaddressed problem worldwide that often deprives patients of optimal medication choices and places them at risk for life-threatening reactions. Underdiagnosis and overdiagnosis are common and due to the lack of standardized definitions and biomarkers. The true burden of DA is unknown, and recent efforts in data gathering through electronic medical records are starting to provide emerging patterns around the world. Ten percent of the general population engaged in health care claim to have a DA, and the most common label is penicillin allergy. Up to 20% of emergency room visits for anaphylaxis are due to DA and 15%-20% of hospitalized patients report DA. It is estimated that DA will increase based on the availability and use of new and targeted antibiotics, vaccines, chemotherapies, biologicals, and small molecules, which are aimed at improving patient's options and quality of life. Global and regional variations in the prevalence of diseases such as human immunodeficiency virus and mycobacterial diseases, and the drugs used to treat these infections have an impact on DA. The aim of this review is to provide an update on the global impact of DA by presenting emerging data on drug epidemiology in adult and pediatric populations.

Comparison of the passive mast cell activation test with the basophil activation test for diagnosis of perioperative rocuronium hypersensitivity

BACKGROUND

Rocuronium is a major cause of perioperative hypersensitivity (POH). Skin tests (STs) and quantification of specific immunoglobulin E antibodies (sIgEs) can yield incongruent results. In such difficult cases, the basophil activation test (BAT) can be helpful. Here, we evaluated the passive mast cell activation test (pMAT) as a substitute of BAT as part of the diagnostic tests for rocuronium allergy.

METHODS

Sera from patients with a suspected POH reaction potentially related to rocuronium were included. All patients had a complete diagnostic investigation, including STs, quantification of sIgEs to morphine and rocuronium, and BAT. For execution of pMAT, human mast cells were generated from healthy donor peripheral blood CD34+ progenitor cells and sensitised overnight with patient sera.

RESULTS

In total, 90 sera were studied: 41 from ST+sIgE+ patients, 13 from ST-sIgE- patients, 20 from ST+sIgE- patients, and 16 from ST-sIgE+ patients. According to BAT results, patients were further allocated into subgroups. Of the 38 BAT+ patients, 25 (66%) showed a positive pMAT as well. Of the 44 BAT- patients, 43 (98%) also showed a negative pMAT. Mast cells that were not passively sensitised did not respond to rocuronium.

CONCLUSIONS

We show that the pMAT, in many cases, can substitute for BAT in the diagnosis of rocuronium hypersensitivity and advance diagnosis in difficult cases with uncertain ST or sIgE results when BAT is not locally available.

Rocuronium-Induced Anaphylaxis in the Perioperative Period: A Clinical Review

Rocuronium, a nondepolarizing neuromuscular blocking agent used for muscle relaxation especially during endotracheal intubation, can cause hypersensitivity reactions. This article provides an overview of anaphylactic reactions; risk factors; and the pathophysiology, presentation, diagnosis, treatment, and nursing implications associated with rocuronium-induced anaphylaxis. Life-threatening anaphylaxis can be immunoglobulin E-mediated or non-immunoglobulin E-mediated and usually occurs after the first dose. Anaphylaxis can present with hypotension and bronchospasm; cutaneal symptoms, such as erythema, may not be obvious. Diagnosis is initially presumptive and may require a transesophageal echocardiogram to rule out other causes of hypotension (eg, pulmonary embolus). Emergency treatment begins with epinephrine administration and fluid boluses; cardiac support devices may be needed. Definitive diagnosis requires early measurement of histamine and tryptase levels and skin testing after the patient recovers from the reaction. Perioperative nurses should be prepared to participate in emergency treatment of anaphylaxis and advocate for testing for a definitive diagnosis.

Anaphylaxis mortality in the perioperative setting: Epidemiology, elicitors, risk factors and knowledge gaps

Perioperative anaphylaxis (PA) is a severe condition that can be fatal, but data on PA mortality are scarce. The aim of this article is to review the epidemiology, elicitors and risk factors for PA mortality and identify knowledge gaps and areas for improvement regarding the management of severe PA. PA affects about 100 cases per million procedures. Mortality is rare, estimated at 3 to 5 cases per million procedures, but the PA mortality rate is higher than for other anaphylaxis aetiologies, at 1.4% to 4.8%. However, the data are incomplete. Published data mention neuromuscular blocking agents and antibiotics, mainly penicillin and cefazolin, as the main causes of fatal PA. Reported risk factors for fatal PA vary in different countries. Most frequently occurring comorbidities are obesity, male gender, cardiovascular diseases and ongoing treatment with beta-blockers. However, there are no clues about how these factors interact and the impact of individual risk factors. The pathophysiology of fatal PA is still not completely known. Genetic factors such as deficiency in PAF-acetyl hydrolase and hereditary alpha-tryptasemia, have been reported as modulators of severe anaphylaxis and possible targets for specific treatments. Our review underlines unmet needs in the field of fatal PA. Although we confirmed the need for timely administration of an adequate dose of adrenaline and the proper infusion of fluids, there is no evidence-based data on the proper dose of intravenous titrated adrenaline and which clinical manifestations would flag the need for fluid therapy. There are no large clinical studies supporting the administration of alternative vasopressors, such as glucagon and methylene blue. Further research on pathophysiological mechanisms of PA and its severity may address these issues and help clinicians to define new therapeutic approaches.

Perioperative anaphylaxis: when the allergological work-up goes negative

PURPOSE OF REVIEW

Perioperative anaphylaxis (POA) is rare but is associated with significant morbidity and mortality. Patients are referred to the allergist to identify the mechanism of the reaction, the causative agent and make recommendations regarding subsequent anaesthesia. Despite a well conducted allergological evaluation, the causative agent is not found in 30-60% of these reactions, leaving patients without a well established diagnosis.

RECENT FINDINGS

Several mechanisms can induce POA. In addition to the well known IgE-mediated reactions, IgG-mediated reaction, MRGPR-X2-related reaction or nonspecific histamine release may be involved. These situations are not easily assessed by the allergological workup.

SUMMARY

When the allergological workup is negative, the situation should be reassessed with the team present at the time of the reaction to confirm the reality of the hypersensitivity reaction and to search for a possible differential diagnosis. If POA is confirmed, the allergological evaluation should be repeated, ensuring proper execution according to current guidelines and including the search for hidden allergens. Specific IgE assays or basophil activation tests may be of interest. In case of negative results, a closely monitored drug challenge test, in coordination with the anaesthesia teams, may be useful to avoid the exclusion of any drug injected during the reaction.

Suspected perioperative anaphylaxis: are we making the correct diagnosis?

We provide a commentary on aspects of a prospective study of the epidemiology of perioperative anaphylaxis in Japan (Japanese Epidemiologic Study for Perioperative Anaphylaxis [JESPA]). Accurate diagnosis of perioperative anaphylaxis is important for research but essential for clinical safety. We evaluate the diagnostic approach used in the JESPA study and caution against over-reliance on diagnostic tests that lack sensitivity and specificity when clinical data suggest an immediate perioperative hypersensitivity reaction is likely.

Pholcodine, perioperative anaphylaxis, and the European Medicines Agency: finally the decision to remove pholcodine from the market in the European Union

Two recent case-control studies, both published in the British Journal of Anaesthesia, have shown that intake of pholcodine-containing cough medicines during the year preceding general anaesthesia significantly increased the risk of anaphylaxis caused by neuromuscular blocking agents. Both a French multicentre study and a single-centre study from Western Australia offer strong support to the pholcodine hypothesis for IgE-sensitisation to neuromuscular blocking agents. The European Medicines Agency, criticised for not taking preventive action at its first assessment of pholcodine in 2011, finally recommended a stop to sales of all pholcodine-containing medicines throughout the EU on December 1, 2022. Time will tell whether this reduces the incidence of perioperative anaphylaxis in the EU, as in Scandinavia.

Pholcodine exposure increases the risk of perioperative anaphylaxis to neuromuscular blocking agents: the ALPHO case-control study

BACKGROUND

Neuromuscular blocking agents (NMBAs) are among the leading cause of perioperative anaphylaxis, and most of these reactions are IgE mediated. Allergic sensitisation induced by environmental exposure to other quaternary ammonium-containing compounds, such as pholcodine, has been suggested. The aim of this study was to assess the relationship between pholcodine exposure and NMBA-related anaphylaxis.

METHODS

ALPHO was a multicentre case-control study, comparing pholcodine exposure within a year before anaesthesia between patients with NMBA-related perioperative anaphylaxis (cases) and control patients with uneventful anaesthesia in France. Each case was matched to two controls by age, sex, type of NMBA, geographic area, and season. Pholcodine exposure was assessed by a self-administered questionnaire and pharmaceutical history retrieved from pharmacy records. The diagnostic values of anti-pholcodine and anti-quaternary ammonium specific IgE (sIgE) were also evaluated.

RESULTS

Overall, 167 cases were matched with 334 controls. NMBA-related anaphylaxis was significantly associated with pholcodine consumption (odds ratio 4.2; 95% confidence interval 2.3-7.0) and occupational exposure to quaternary ammonium compounds (odds ratio 6.1; 95% confidence interval 2.7-13.6), suggesting that apart from pholcodine, other environmental factors can also lead to sensitisation to NMBAs. Pholcodine and quaternary ammonium sIgEs had a high negative predictive value (99.9%) but a very low positive predictive value (<3%) for identifying NMBA-related reactions.

CONCLUSIONS

Patients exposed to pholcodine 12 months before NMBA exposure have a significantly higher risk of an NMBA-related anaphylaxis. The low positive predictive values of pholcodine and quaternary ammonium sIgEs precludes their use to identify a population with a high risk of NMBA-related anaphylaxis.

CLINICAL TRIAL REGISTRATION

NCT02250729.

The Japanese Epidemiologic Study for Perioperative Anaphylaxis, a prospective nationwide study: allergen exposure, epidemiology, and diagnosis of anaphylaxis during general anaesthesia

BACKGROUND

Diagnosis of perioperative anaphylaxis is often challenging. This study describes the utility of a newly developed tool for identifying patients with a high possibility of anaphylaxis, and aimed to investigate the frequency of anaphylaxis with each drug during the perioperative period in Japan.

METHODS

This study included patients with anaphylaxis of Grade 2 or higher severity during general anaesthesia at 42 facilities across Japan in 2019 and 2020. We developed and adopted a unique objective evaluation tool yielding a composite score for diagnosing anaphylaxis, which includes the results of skin tests and basophil activation tests, and clinical scores for perioperative anaphylaxis. The number of cases using each drug and the total number of anaphylaxis cases were investigated to calculate the frequency of anaphylaxis.

RESULTS

General anaesthesia was performed in 218 936 cases, which included 55 patients with suspected perioperative anaphylaxis. The developed composite score diagnosed 43 of them with a high probability of anaphylaxis. The causative agent was identified in 32 cases. Plasma histamine levels showed high diagnostic accuracy for anaphylaxis. The top causative agents were rocuronium (10 cases in 210 852 patients, 0.005%), sugammadex (7 cases in 150 629 patients, 0.005%), and cefazolin (7 cases in 106 005 patients, 0.007%).

CONCLUSIONS

We developed a composite tool to diagnose anaphylaxis, and found that the combination of tryptase levels, skin testing, and basophil activation testing results and clinical score improved the certainty of anaphylaxis diagnosis. The incidence of perioperative anaphylaxis in our study was 1 in about 5000 general anaesthesia cases.

CLINICAL TRIAL REGISTRATION

UMIN000035350.

Intraoperative Kounis Syndrome and Fixation Errors: A Case Report

Postinduction hypotension, though frequently due to anesthetic medications, has a variety of causes. We present a case of presumed intraoperative Kounis syndrome, or anaphylaxis-induced coronary vasospasm, in which the patient's perioperative course was initially attributed to anesthesia-induced hypotension and iatrogenic rebound hypertension leading to Takotsubo cardiomyopathy. A second anesthetic event with immediate recurrence of hypotension after the patient received levetiracetam appears to confirm the diagnosis of Kounis syndrome. In this report, we discuss the fixation error that led to this patient's original misdiagnosis.

Neuromuscular blocking agent induced hypersensitivity reaction exploration: an update

Acute hypersensitivity reactions (AHRs) occurring in present-day anaesthesia can have severe, sometimes fatal, consequences and their incidence is increasing. The most frequent allergens responsible for AHR during anaesthesia are neuromuscular blocking agents (NMBAs) (70% of the cases) followed by antibiotics (18%), patent blue dye and methylene blue dye (5%), and latex (5%). Following an AHR, strategies for subsequent anaesthetic procedures (especially the choice of an NMBA) may be difficult to formulate due to inconclusive diagnostic analysis in up to 30% of AHRs. Current diagnosis of AHR relies on the detection of mast cell degranulation products and drug-specific type E immunoglobulins (IgE) in order to document an IgE-mediated anaphylaxis (IgE endotype). Nonetheless, other IgE-independent pathways can be involved in AHR, but their detection is not currently available in standard situations. The different mechanisms (endotypes) involved in peri-operative AHR may contribute to the inconclusive diagnostic work-up and this generates uncertainty concerning the culpable drug and strategy for subsequent anaesthetic procedures. This review provides details on the IgE endotype; an update on non-IgE related endotypes and the novel diagnostic tools that could characterise them. This detailed update is intended to provide explicit clinical reasoning tools to the anaesthesiologist faced with an incomplete AHR diagnostic work-up and to facilitate the decision-making process regarding anaesthetic procedures following an AHR to NMBAs.

Incidence of perioperative hypersensitivity reactions: A single-center, prospective, US cohort experience

Background

A previous study, using administrative data, reported an incidence of perioperative anaphylaxis (POA) of 1:6537 procedures in the United States.

Objective

We sought to determine the incidence of POA in a prospective US cohort.

Methods

Adult participants undergoing a procedure at a single tertiary care center were studied prospectively between April 2018 and January 2022. Subinvestigators recorded vital signs and skin checks preoperatively, 15 minutes into induction, and hourly thereafter until 1 hour into the postoperative period. If participants developed an adverse reaction, additional variables were documented: causal agent(s) exposure, type of nonallergic adverse reaction, Sixth National Audit Project severity score, evidence of mast cell activation by serum acute and baseline tryptase pairing, Allergy consult, and causal agent identification.

Results

Among 939 procedures (mean age, 59.25 ± 14.78 years; 58% females; 87% White), there were 12 (1.3%) cases with an identified adverse reaction. Nine cases were classified as nonhypersensitivity adverse reactions (1%) and 3 as possible hypersensitivity reactions (0.3%); 1 case was classified as suspected perioperative hypersensitivity and 2 as POA (0.2%). Both POA cases were males, had previous procedures, had evidence of mast cell activation, had a Sixth National Audit Project score of 3, and were referred to Allergy for further evaluation. There were 9 participants who developed a nonhypersensitivity adverse reaction: relative overdose of anesthetic (n = 6), transient rash (n = 2), and isolated bronchospasm (n = 1). All transient rashes were observed during undraping protocol.

Conclusions

In our prospective study, the incidence of POA is 1:470 procedures. Our study suggests that the incidence of POA may be higher than previously reported.

The Nonirritating Concentrations of Neuromuscular Blocking Agents and Related Compounds

BACKGROUND

Skin testing (ST) concentrations of neuromuscular blocking agents (NMBAs), NMBA-reversal agents, and the sugammadex-rocuronium inclusion complex (S-R-Cx) vary widely among reports.

OBJECTIVE

To determine maximal ST nonirritant concentrations (NICs) of NMBAs (cisatracurium, rocuronium, succinylcholine, and vecuronium), NMBA-reversal agents (neostigmine and sugammadex), and S-R-Cx in NMBA-tolerant and NMBA-naïve participants.

METHODS

A single-center, prospective study between October 2019 and November 2021 of adult participants with or without a planned surgical procedure. The reference standard was tolerance of medication tested during a procedure (NMBA-tolerant group) before ST. Participants received skin prick testing (SPT) and intradermal test (IDT) injections at 5-7 increasing concentrations of 1 or more medications. All medications were reconstituted according to package insert instructions and diluted with 0.9% saline. A concentration was considered irritant when more than 5% of participants had a positive test per ST positivity criteria (wheal ≥3 mm than initial wheal and associated erythema of the same size or greater than wheal). We also compared our results with current guidelines.

RESULTS

A total of 187 participants (78% NMBA-tolerant) underwent 7812 skin tests. All undiluted SPT concentrations were nonirritant. We found the following maximal IDT NICs (mg/mL): cisatracurium (0.02), rocuronium (0.05), succinylcholine (0.8), vecuronium (0.01), neostigmine (0.2), sugammadex (50), and S-R-Cx (sugammadex 7.14 + rocuronium 2).

CONCLUSION

Our results suggest that SPT may be performed with undiluted stock concentrations. We confirm maximal IDT NICs for cisatracurium and rocuronium. We also propose that currently recommended maximal IDT NICs of succinylcholine, neostigmine, sugammadex, and S-R-Cx could be increased, whereas the maximal IDT NIC of vecuronium could be decreased compared with current guidelines and prior reports.

Perioperative Hypersensitivity Evaluation and Management: A Practical Approach

Perioperative hypersensitivity (POH) is an uncommon, potentially life-threatening event. Identification of POH can be difficult given the lack of familiarity, physiological effects of anesthesia, draping of the patient during surgery, and potential nonimmunological factors contributing to signs and symptoms. Given the unique nature and large number of medications administered in the perioperative setting, evaluation of POH can be challenging. In this paper, we present a practical approach to management with an emphasis on understanding what happens in the operating room, the overlap of signs and symptoms between nonimmunological and immunological reactions, acute management, and subsequent evaluation. In addition, we provide a strategy for further review of an initially negative evaluation and emphasize the importance of establishing management plans for the patient as well as providing recommendations to the medical, anesthesia, and surgical teams for future surgeries. A critical factor for successful management at all points in the process is a close collaboration between the anesthesia and the allergy teams.

Perioperative Anaphylaxis

Anesthesiologists routinely manage patients receiving drugs and agents, all of which have the potential for anaphylaxis, the life-threatening presentation of an allergic reaction. Clinicians must be ready to diagnose and manage the acute cardiopulmonary dysfunction that occurs.

Management of Suspected Life-Threatening Perioperative Anaphylaxis and Risk Factors for Near-Fatal and Fatal Outcomes: A Retrospective Study in China

Purpose

Perioperative anaphylaxis (POA) is an acute severe systemic hypersensitivity reaction characterized by life-threatening respiratory and circulatory collapse. In our previous study, we reported the epidemiology of suspected POA in China. In the present study, we aimed to elucidate the management and outcomes of these cases and further verify the risk factors for near-fatal and fatal outcomes.

Patients and Methods

This was a retrospective study of 447 cases of suspected life-threatening POA encountered at 112 tertiary hospitals in mainland China between September 2018 and August 2019. Patient characteristics, symptoms, duration of hypotension, treatments, and clinical outcomes were documented. Bivariate logistic regression was used to identify risk factors for near-fatal and fatal outcomes.

Results

Most cases of suspected POA (89.9%) were recognized and treated within 5 min. Epinephrine was administered as the initial treatment in 232 (51.9%) cases. Corticosteroids (26.6%), other vasoactive drugs (18.3%), and bronchodilators (1.6%) were also administered as the initial treatment instead of epinephrine. The initial dosage of epinephrine (median, 35 µg) was insufficient according to the anaphylaxis guidelines. On multivariable analysis, age ≥65 years (odds ratio [OR] 7.48; 95% confidence interval [CI]: 1.33-41.87, P=0.022), ASA physical status IV (OR 17.68; 95% CI: 4.53-68.94; P<0.001), and hypotension duration ≥15 min (OR 3.63; 95% CI: 1.11-11.87; P=0.033) were risk factors for fatal and near-fatal outcomes.

Conclusion

Most cases in this study were managed in a timely manner, but the epinephrine application should be optimized according to the guidelines. Age ≥65 years, ASA physical status IV, and long-term hypotension were risk factors for near-fatal and fatal outcomes.

Could Artificial Intelligence Prevent Intraoperative Anaphylaxis? Reference Review and Proof of Concept

Drugs and various medical substances have been used for many decades to diagnose or treat diseases. Procedures like surgery and anesthesia (either local or general) use different pharmacological products during these events. In most of the cases, the procedure is safe and the physician performs the technique without incidents. Although they are safe for use, these substances (including drugs) may have adverse effects, varying from mild ones to life-threatening reactions in a minority of patients. Artificial intelligence may be a useful tool in approximating the risk of anaphylaxis before undertaking a medical procedure. This material presents these undesirable responses produced by medical products from a multidisciplinary point of view. Moreover, we present a proof of concept for using artificial intelligence as a possible guardship against intraoperative anaphylaxis.

Quaternary ammonium compounds in hypersensitivity reactions

Quaternary ammonium compounds (QAC) are commonly used disinfectants, antiseptics, preservatives, and detergents due to their antibacterial property and represent the first used biocides before phenolic or nitrogen products. Their common structure consists of one or more quaternary ammonium bound with four lateral substituents. Their amphiphilic structure allows them to intercalate into microorganism surfaces which induces an unstable and porous membrane that explains their antimicrobial activity towards bacteria, fungi, and viruses. QAC are thus found in many areas, such as household products, medicines, hygiene products, cosmetics, agriculture, or industrial products but are also used in medical practice as disinfectants and antiseptics and in health care facilities where they are used for cleaning floors and walls. QAC exposure has already been involved in occupational asthma in healthcare workers or professional cleaners by many authors. They also have been suggested to play a role in contact dermatitis (CD) and urticaria in workers using cosmetics such as hairdressers or healthcare workers, inciting reglementary agencies to make recommendations regarding those products. However, distinguishing the irritant or sensitizing properties of chemicals is complex and as a result, the sensitizing property of QAC is still controverted. Moreover, the precise mechanisms underlying the possible sensitization effect are still under investigation, and to date, only a few studies have documented an immunological mechanism. Besides, QAC have been suggested to be responsible for neuromuscular blocking agents (NMBA) sensitization by cross-reactivity. This hypothesis is supported by a higher prevalence of quaternary ammonium (QA)-specific IgE in the professionally exposed populations, such as hairdressers, cleaners, or healthcare workers, suggesting that the sensitization happens with structurally similar compounds present in the environment. This review summarizes the newest knowledge about QAC and their role in hypersensitivities. After describing the different QAC, their structure and use, the most relevant studies about the effects of QAC on the immune system will be reviewed and discussed.

Successful management of rocuronium-induced anaphylaxis with sugammadex: A case report

Although anaphylaxis during anaesthesia is a rare event, neuromuscular blocking drugs are responsible for 62% of anaesthesia-related anaphylaxis. However, sugammadex, a modified gamma-cyclodextrin, can encapsulate rocuronium molecules and cause the rapid reversal of the neuromuscular blockade. A 68-year-old man who presented for a radical prostatectomy was induced with IV fentanyl/propofol/rocuronium. He had not received rocuronium previously but had received cisatracurium. Shortly after anaesthesia, the patient’s heart rate abruptly increased, and systolic blood pressure (SBP) dropped to 40 mm Hg. Despite cardiopulmonary resuscitation and intensive management, his haemodynamic stability did not improve until he received IV sugammadex, 200 mg. Intradermal skin tests showed he was positive for cisatracurium, rocuronium and succinylcholine. The patient was suspected to have cross-reactivity of rocuronium with cisatracurium. This case highlights the potential benefit of sugammadex as an adjunct to conventional measures during rocuronium-induced anaphylaxis.

Penicillin Allergy and Perioperative Anaphylaxis

Penicillin allergy is the most commonly reported drug allergy, while perioperative anaphylaxis is overall rare. This review covers the epidemiology of both penicillin allergy and perioperative anaphylaxis both separately and taken together. Considerations regarding anaphylaxis to penicillin during pregnancy are also discussed, since penicillin is the drug of choice for Group B Streptococcus prophylaxis. The minimal cross reactivity between penicillins and cephalosporins is addressed, since the vast majority of patients with a penicillin allergy label can receive perioperative cephalosporins. The management of the patient who has experienced perioperative anaphylaxis, including the importance of allergy referral is covered. Approaches to pre-operative penicillin allergy evaluations and opportunities for education are highlighted.

Contemporary use of antimicrobial prophylaxis for surgical patients: An observational cohort study

BACKGROUND

Antimicrobial prophylaxis is commonly used to prevent surgical site infection (SSI), despite concerns of overuse leading to antimicrobial resistance. However, it is unclear how often antimicrobials are used and whether guidelines are followed.

OBJECTIVES

To describe contemporary clinical practice for antimicrobial prophylaxis including guideline compliance, the rate of postoperative infection and associated side effects.

DESIGN

A prospective, multicentre, observational cohort study.

SETTING

Twelve United Kingdom National Health Service hospitals.

PARTICIPANTS

One thousand one hundred and sixteen patients, aged at least 18 years undergoing specific colo-rectal, obstetric, gynaecological, urological or orthopaedic surgical procedures.

EXPOSURE

Compliance with guidelines for antimicrobial prophylaxis.

OUTCOMES

The primary outcome was SSI within 30 days after surgery. Secondary outcomes were number of doses of antimicrobials for prophylaxis and to treat infection, incidence of antimicrobial-related side effects and mortality within 30 days after surgery. Data are presented as number with percentage (%) or median with interquartile range [IQR].Results of logistic regression analyses are presented as odds ratio/rate ratio (OR/RR) with 95% confidence intervals (95% CIs).

RESULTS

1102 out of 1106 (99.6%) patients received antimicrobial prophylaxis, which was compliant with local guidelines in 929 out of 1102 (84.3%) cases. 2169 out of 51 28 (42.3%) doses of antimicrobials were administered as prophylaxis (median 1 [1 to 2] dose) and 2959 out of 5128 (57.7%) were administered to treat an infection (median 21 [11 to 28] doses). 56 patients (5.2%) developed SSI. Antimicrobial prophylaxis administered according to local guidelines was not associated with a lower incidence of SSI compared with administration outside guidelines [OR 0.90 (0.35 to 2.29); P  = 0.823]. 23 out of 1072 (2.2%) patients experienced a side effect of antimicrobial therapy. 7 out of 1082 (0.6%) patients died. The median hospital stay was 3 [1 to 5] days.

CONCLUSION

Antimicrobial prophylaxis was administered for almost all the surgical procedures under investigation. However, this was not always compliant with guidelines. Further research is required to determine whether the amount of prophylactic antimicrobials could be safely and effectively reduced without increasing the incidence of SSI.

Acute Urticaria and Anaphylaxis: Differences and Similarities in Clinical Management

Acute urticaria is a common condition that presents with wheals and/or angioedema. However, these symptoms are also frequent in anaphylaxis, a life-threatening reaction that should be immediately diagnosed and treated. In both, mast cells play a central role in the physiopathology. Causes and triggers of acute urticaria and anaphylaxis are similar in general, but some peculiarities can be observed. The diagnostic approach may differ, accordingly to the condition, suspicious causes, age groups and regions. Adrenaline is the first-line treatment for anaphylaxis, but not for acute urticaria, where H1-antihistamines are the first choice. In this paper, we review the main aspects, similarities and differences regarding definitions, mechanisms, causes, diagnosis and treatment of acute urticaria and anaphylaxis.

Incidence of intraoperative anaphylaxis caused by blood products: a 12-year single-center, retrospective study

PURPOSE

Intraoperative anaphylaxis caused by blood products is uncommon, but it is unclear whether the rarity of this reaction is attributable to the difficulty of diagnosis, underreporting, or both. We investigated the incidence of intraoperative transfusion anaphylaxis and its reporting to the hemovigilance system.

METHODS

We retrospectively reviewed cases wherein general anesthesia was used at a single hospital during a 12-year period. Cases of intraoperative anaphylaxis were extracted using an electronic search strategy and determined using the recently developed grading and clinical scoring system. The causative blood products were determined by the onset duration based on literature regarding intraoperative transfusion anaphylaxis cases.

RESULTS

Among the 62,146 general anesthesia cases, 22 cases of intraoperative anaphylaxis were identified, and 11 of the 22 cases received transfusions before the onset of anaphylaxis. Intraoperative transfusion anaphylaxis was defined as occurring within 30 min of transfusion. Finally, nine cases of intraoperative transfusion anaphylaxis were analyzed. The overall incidence of intraoperative transfusion anaphylaxis was 1/3,994, with the highest incidence noted for fresh frozen plasma (1/2146; 95% confidence interval [CI] 1/6610-1/920), platelet concentrate (1/2348; 95% CI 1/92,742-1/422), and red blood cells (1/22,867; 95% CI 1/903,199-1/4,105). No evidence indicated that these cases were reported to the Japanese hemovigilance system, although all intraoperative transfusion anaphylaxis cases were diagnosed by anesthesiologists.

CONCLUSION

The incidence of intraoperative anaphylaxis caused by blood products was higher than that reported and may be underreported to the Japanese hemovigilance system. Further research, particularly multicenter studies, is needed to confirm our results.

Perioperative anaphylaxis to fibrin sealants in children with Noonan Syndrome: A retrospective study

BACKGROUND

In the diagnosis of perioperative anaphylaxis, it is essential to define its cause to prevent future reexposures, especially in children with Noonan Syndrome who are characterized by a large number of systemic features and wide-ranging dysmorphia. From an oral surgeon's point of view, apart from an increased risk of tumor incidence, diverse hematologic anomalies are of high concern.

OBJECTIVE

Perioperative management of such patients often requires the use of fibrin sealants, which contain aprotinin. A certain number of anaphylaxis cases have been observed in our daily practice during such treatment, which was the reason for this evaluation.

METHODS

The study was conducted to retrospectively review perioperative anaphylaxis grade II and above in children with Noonan Syndrome who underwent surgeries in the Department of Oral Surgery, Medical University of Lodz, between 2006 and 2021.

RESULTS

Out of the 16 cases of suspected anaphylaxis to aprotinin, 14 were observed in children with Noonan Syndrome. The postoperative serologic screening revealed positive results for qualitative aprotinin-specific immunoglobulin (Ig) G, highly elevated quantitative aprotinin-specific IgG, and slightly elevated aprotinin-specific IgE antibodies. Interestingly, previous aprotinin administration or contact in the past 12 months was excluded.

CONCLUSION

Given that fibrin sealants are typically used in various surgical practices and although the anaphylaxis reactions in such cases are rare, it is essential to be cautious in patients with RASopathies who are at a high risk of developing anaphylaxis.

Clinical characteristics and allergen detection of perioperative anaphylaxis: a 12-year retrospective analysis from an anesthesia clinic in China

Abstract

Background

Anaphylaxis during anesthesia is a rare but often a potentially life-threatening event for patients. Identifying culprit agents responsible for anaphylaxis is of great important for avoiding potential re-exposure to allergens, but it poses great challenge for anesthetists. This retrospective study aimed to analyze the culprits of patients with a history of perioperative anaphylaxis referred to an anesthesia allergy clinic in China, and to evaluate the role of allergy diagnostic tests in clinical practice.

Methods

A total of 145 patients (102 female/43 male) who attended the Anesthesia Allergy Clinic for allergen detection between 1 January 2009 and 31 December 2020 were reviewed retrospectively. Clinical characteristics, results of allergy diagnostic tests including skin, and/or basophil activation tests, and the incidence of repeat anaphylaxis after use of recommended alternative anesthetics were obtained.

Results

Of these 145 patients, 109 patients (75.2%, 74 females/35 males) were determined to experience perioperative anaphylaxis. The most common presenting clinical feature was cardiovascular manifestations (n = 63, 57.8%). According to diagnostic work up, the most common causative agents for perioperative anaphylaxis were neuromuscular blocking agents (n = 35, 32.1%). After diagnostic work up, 52 patients underwent repeat anesthesia. None of these patients experienced recurrent anaphylaxis.

Conclusions

This study suggests that neuromuscular blocking agents are the main cause of perioperative anaphylaxis. For patients with perioperative anaphylaxis, allergy diagnostic tests are essential to identify causative agents, and to find suitable alternative drugs for the future planning of subsequent anesthetics.

Risk predictive tools of perioperative drug hypersensitivity reaction: A case-control study

Objective

We aimed to determine the risk factors of perioperative drug hypersensitivity reaction (DHR) and develop a predictive score for use in clinical practice.

Methods

A case-control study was conducted in patients who underwent anesthesia at a tertiary hospital in Thailand, between 2015–2018. DHR cases were graded clinically from 1 to 4 according to the World Federation of Societies of Anesthesiologists by two anesthesiologists. Controls were randomly matched with cases (ratio 2:1) by age group and month and type of surgery. Patient and anesthesia-related factors and agents given intraoperatively were recorded. A risk score was derived from the coefficients of the significant predictors of the final multivariate logistic regression model. Risk scores, adjusted odds ratios (OR) for perioperative DHR and 95% confidence intervals (CI) were determined.

Results

Overall, 325 cases and 650 controls were recruited. The severity of DHR was grade 1 (72.9%), grade 2 (24%), and grade 3 (3.1%). Our risk predictive tools for perioperative DHR provided a sensitivity of 62% and specificity of 65%. Predictive scores of subgroups of moderate to severe DHR showed high specificity (80%) but low sensitivity (47%). Common predictors of overall DHR and moderate to severe DHR were history of drug allergy to 2 or more drug categories (score 2.5–3.5), being allergic to analgesics (score 2.5–4.0), and intraoperative morphine use (score of 1). The sole predictor of high-risk perioperative DHR (score ≥3.5) was airway management with an endotracheal tube intubation (OR 5.6, 95% CI 2.2–14.4) whereas history of allergic rhinitis (OR 11.7, 95% CI 1.3–105.1) was a predictor of high-risk moderate to severe DHR (score ≥2.5).

Conclusions

Our predictive tool for perioperative DHR provided a modest predictive ability. History of drug allergies, rhinitis, morphine use and endotracheal intubation were significant risk factors of DHR after adjusting for age and type of surgery.

Intraoperative Cell Salvage for Women at High Risk of Postpartum Hemorrhage During Cesarean Section: a Systematic Review and Meta-analysis

Postpartum hemorrhage (PPH) can lead to substantial blood loss that compromises maternal hemodynamic stability and consequently cause severe maternal complications such as organ dysfunction or death. Intraoperative cell salvage (IOCS), an effective method of blood conservation used in other surgical specialties, can be an alternative intervention for managing PPH. Thus, our aim was to evaluate the efficacy and safety of IOCS for women at high risk of PPH undergoing cesarean sections. We conducted a systematic search of electronic databases from inception to February 25, 2021 for randomized controlled studies and observational studies published in English or Mandarin about IOCS use in cesarean sections. Primary outcomes of interest were changes in postoperative hematologic parameters and any adverse events reported among patients that had IOCS and controls that had an allogeneic blood transfusion. The certainty of the evidence of the outcomes was evaluated using the GRADE approach. A total of 24 studies with 5872 patients were included in the meta-analysis. Eleven randomized controlled trials (RCTs), and 13 observational studies were analyzed. Postoperative hemoglobin levels were higher among patients with IOCS SMD 0.39 (95% CI; 0.20, 0.60; P < 0.001, high certainty). Allogeneic blood transfusion increased adverse events RR = 1.81(95% CI; 1.24, 2.62; P = 0.002, low certainty). IOCS shortened hospital stay SMD - 0.59 (95% CI: - 0.98, - 0.19; P = 0.004, low certainty) and shortened prothrombin time SMD - 0.67 (95% CI; - 1.31, - 0.04), P = 0.037, low certainty). The lower incidence of transfusion-related adverse events and shorter hospital stay among other findings demonstrate that IOCS use in obstetrics is an effective and safe alternative for the management of PPH; however, high-quality randomized control studies are required to confirm this evidence.

What do we know about perioperative hypersensitivity reactions and what can we do to improve perioperative safety?

Hypersensitivity reactions are an important aspect of perioperative care and are a crucial interdisciplinary issue in anaesthesiological practice, as well as allergological and laboratory diagnostics. This phenomenon was observed as early as the 1980s and 1990s in Western European countries, and knowledge on this subject has grown significantly over time. Although hypersensitivity reactions are not frequent events (the incidence of perioperative hypersensitivity reactions ranges from 1:386 to 1:13 000 procedures, with higher frequency - 1 per 6500 general anaesthesias with neuromuscular blocking agents administrations), their courses are unfortunately serious and life-threatening. It should also be noted that there is no information regarding the occurrence of perioperative hypersensitivity reactions in many countries. Hence, global assessment of the problem is underestimated. The primary source of actual knowledge comes from epidemiological studies, which indicate an increasing frequency of hypersensitivity reaction occurrence and changes in aetiological factors. The first report from France (1984 to 1989) described two main causes - neuromuscular blocking agents and hypnotic agents. The following years confirmed an increase in perioperative hypersensitivity reactions associated with latex and antibiotics. The most recent data from the National Audit Project 6 indicated increased participation of antibiotics, chlorhexidine, and contrast agents. The results of epidemiological analyses are the basis of medical management guidelines and practice modification. Thanks to the activity of many organisations monitoring the intensity and nature of perioperative hypersensitivity reactions, guidelines for diagnostics and management have been developed. This article presents the results of numerous studies, including the first and the most recent, from various geographical regions. The clinical significance, pathogenesis mechanisms are also discussed. This publication also presents important directions for further scientific and epidemiological research on perioperative hypersensitivity reactions.Key messagesThe incidence of perioperative hypersensitivity reactions ranges from 1:386 to 1:13 000 procedures, with higher frequency - 1 per 6500 general anaesthesias with neuromuscular blocking agents administrations.Reactions may occur during the first episode of anaesthesia, most frequently in the induction of general anaesthesia, and much less frequently during postoperative follow-up.The first reports of perioperative hypersensitivity reaction come from the 1990s, and knowledge on this subject has grown significantly over time.In many countries, multidisciplinary teams and organisations have been established to identify, monitor the occurrence of this phenomenon, and have set the directions of medical activities and have changed the rules and recommendations.There is no information about the occurrence of perioperative hypersensitivity reactions in many countries, and global assessment of the problem is underestimated. Additionally, there is a great need to develop a system to monitor their occurrence in other countries.The long-term epidemiologic studies have demonstrated variability in pharmacologic triggers. However, the main pharmacological substances (antibiotics, muscle relaxants, disinfectans, contrast agents) are related to aspects of patient safety during anaesthesia.

Perioperative Anaphylaxis

Perioperative anaphylaxis is a potentially life-threatening and under-recognized event most commonly caused by antibiotics, neuromuscular blocking agents, dyes, latex, and disinfectants. This review provides updates in the epidemiology and pathogenesis of perioperative anaphylaxis, discusses culprit agents, and highlights the tenets of management including a comprehensive allergy evaluation.