Patch Testing to Chlorhexidine Digluconate, 1% Aqueous: North American Contact Dermatitis Group Experience, 2015-2020

Background: Chlorhexidine is an antiseptic that may cause allergic contact dermatitis. Objectives: To describe the epidemiology of chlorhexidine allergy and characterize positive patch test reactions. Methods: This retrospective study analyzed patients patch tested to chlorhexidine digluconate 1% aqueous by the North American Contact Dermatitis Group, 2015-2020. Results: Of 14,731 patients tested to chlorhexidine digluconate, 107 (0.7%) had an allergic reaction; of these, 56 (52.3%) reactions were currently clinically relevant. Most (59%) reactions were mild (+), followed by strong (++, 18.7%) and very strong (+++, 6.5%). Common primary dermatitis anatomic sites in chlorhexidine-positive patients were hands (26.4%), face (24.5%), and scattered/generalized distribution (17.9%). Compared with negative patients, chlorhexidine-positive patients were significantly more likely to have dermatitis involving the trunk (11.3% vs 5.1%; P = 0.0036). The most commonly identified source category was skin/health care products (n = 41, 38.3%). Only 11 (10.3%) chlorhexidine reactions were occupationally related; of these, 81.8% were in health care workers. Conclusions: Chlorhexidine digluconate allergy is uncommon, but often clinically relevant. Involvement of the hands, face, and scattered generalized patterns was frequent. Occupationally related reactions were found predominantly in health care workers.

Perioperative anaphylaxis management and testing: a quaternary centre audit

BACKGROUND

Anaphylaxis is a severe, potentially life-threatening generalized or systemic hypersensitivity reaction. Sequential reports have cited anaphylaxis as the most common cause of anaesthesia-related deaths. We undertook an audit at a quaternary centre, examining the management of perioperative anaphylaxis and quality of referrals made to our anaesthesia allergy testing service.

METHODS

The data of 41 patients consulted at St Vincent's Hospital Melbourne for perioperative anaphylaxis between 17th of January 2020 and 20th of January 2022 were analysed. Intervention outcomes included total intravenous fluid administered, adrenaline administration, instigation of CPR and the collection and the timing of serum tryptase samples. We also assessed referral quality, provision of institutional allergy alert and time elapsed from the anaphylaxis event to allergy testing. Contemporaneous Australian and New Zealand Anaesthetic Allergy Group (ANZAAG) guidelines were used as the reference standard for most outcomes.

RESULTS

Our data reveals compliance of <80% with respect to intravenous fluid administration, referral quality and tryptase sampling, particularly at the 4-h timepoint.

CONCLUSION

Surgical leadership and patient advocacy in the post-acute phase would likely facilitate requisite testing and improve the quality of counselling. We recommend institutions adopt a case-by-case review of management compliance with recommendations. Additionally, we advocate for the inclusion of a prompt to the ANZAAG referral form, that encourages the operator to update their patient's institutional allergy alert while awaiting allergy testing.

Effect of body mass index and rocuronium on serum tryptase concentration during volatile general anesthesia: an observational study

OBJECTIVE

Female sex, body mass index (BMI), and neuromuscular blocking agents are risk factors of perioperative hypersensitivity reactions. This study aimed to investigate the effect of rocuronium on serum tryptase concentrations during general anesthesia in overweight and obese women.

METHODS

The study was conducted in two groups: Group I (n=66) underwent volatile anesthesia with rocuronium and group II (n=60) underwent volatile anesthesia without any muscle relaxant. Serum tryptase concentration (STC) measurements were performed at baseline (STC 0) and postoperatively (STC 1). ClinicalTrials.gov: NCT04035707 RESULTS: The highest median value of STC 0 was seen in obese patients (3.44 μg L-1) and it was significantly higher than in overweight (p=0.01) and underweight patients (p=0.03). The maximum STC 0 was observed in overweight patients (20.4 μg L-1). In group I, STC 0 in obese patients presented the highest median value (4.49 μg L-1), and was significantly higher than in overweight patients (p=0.03), and had significantly higher STC 1 than patients with normal BMI (p=0.04). STC 0 and STC 1 in overweight and obese female patients did not differ significantly between groups. STC 1 did not correlate with rocuronium doses. In group I, BMI positively correlated with the duration of rocuronium infusion (rho=0.37) and STC 1 positively correlated with BMI (rho=0.32).

CONCLUSION

Excess weight and obesity predispose to higher preoperative serum tryptase values. Postoperative STC is not linked to rocuronium doses. BMI is the main determinant factor of STC during combined volatile general anesthesia.

Australian and New Zealand Anaesthetic Allergy Group/ Australian and New Zealand College of Anaesthetists Perioperative Anaphylaxis Management Guidelines

Anaphylaxis is an uncommon but important cause of serious morbidity and even mortality in the perioperative period. The Australian and New Zealand College of Anaesthetists (ANZCA) with the Australian and New Zealand Anaesthetic Allergy Group (ANZAAG) have developed clinical management guidelines that include six crisis management cards. The content of the guidelines and cards is based on published literature and other international guidelines for the management of anaesthesia-related and non–anaesthesia-related anaphylaxis. The evidence is summarised in the associated background paper (Perioperative Anaphylaxis Management Guidelines [2016] www.anzca.edu.au/resources/endorsed-guidelines and www.anzaag.com/Mgmt%20Resources.aspx ). These guidelines are intended to apply to anaphylaxis occurring only during the perioperative period. They are not intended to apply to anaphylaxis outside the setting of dedicated monitoring and management by an anaesthetist. In this paper guidelines will be presented along with a brief background to their development.

Perioperative chlorhexidine allergy: Is it serious?

Chlorhexidine is an antiseptic agent, commonly used, in many different preparations, and for multiple purposes. Despite its superior antimicrobial properties, chlorhexidine is a potentially allergenic substance. The following is a review of the current evidence-based knowledge of allergic reactions to chlorhexidine associated with surgical and interventional procedures.

Predictive value of allergy tests for neuromuscular blocking agents: tackling an unmet need

BACKGROUND

Neuromuscular blocking agents (NMBAs) are a predominant cause of perioperative anaphylaxis in Europe. Diagnosis of NMBA allergy relies upon the careful review of the anaesthetic report complemented with skin tests. Additional diagnostic tests are quantification of specific IgE antibodies (sIgE) and basophil activation test (BAT). However, data on the predictive value of the skin tests, the BAT and the sIgE assays (drug-specific and substituted ammonium structures) are limited or not available, mainly because such exploration requires dangerous NMBA provocation tests.

METHODS

In this study, the predictive value of skin test, BAT and measurement of sIgE to substituted ammonium structures is gathered from a review of anaesthetic records of subsequent surgical procedures with NMBA administration and/or occurrence of perioperative incidents.

RESULTS

We investigated a series of 272 patients with perioperative anaphylaxis, of whom 100 had undergone second general anaesthesia. Negative skin test and negative BAT assisted the selection of alternative NMBA, which were well tolerated in all cases. Five patients with a positive sIgE to rocuronium but with negative skin testing and BAT safely received rocuronium during second anaesthesia. Twelve patients with sIgE reactivity to morphine, but negative skin test and BAT to benzylisoquinolines, tolerated administration of cisatracurium or atracurium. Alternatively, benzylisoquinoline allergy went undetected in the morphine solid-phase assay.

CONCLUSIONS

Skin test and BAT have an excellent negative predictive value in our series. The uneventful re-exposure of rocuronium in patients with an isolated positive sIgE result to rocuronium calls into question the predictive value of this assay and suggests sIgE serology to be less clinically predictive than the functional investigations relying upon activation of mast cells or basophils. The presence of a positive sIgE to substituted ammonium structures such as morphine does not preclude further use of benzylisoquinolines.

Impact of national guidelines on reporting anaphylaxis during anaesthesia -- an outcome audit

AIMS

Anaphylaxis during anaesthesia is a rare and potentially fatal event. Adequate reporting and investigation of anaphylaxis associated with anaesthesia results in improved patient safety and outcomes. Guidelines from the Association of Anaesthetists of Great Britain and Ireland (AAGBI) designed to improve this process were first issued in 1990 and updated in 1995, 2003 and 2008. In a setting where no formal guideline was previously in place, we compared the reporting and investigation of anaphylaxis in a large hospital before and after the introduction of the 2008 guideline.

METHODS

A retrospective outcome audit was conducted to compare data from 12 patients referred from April 2006 to May 2008 prior to release of the 2008 AAGBI guidance, with 53 patients referred from 2008 until April 2011. Data were collected using the AAGBI Anaphylaxis Referral Form.

RESULTS

There was an increase in the number of referrals for suspected anaphylaxis following implementation of the AAGBI guidance. The clinical features observed in patients were consistent with previous studies. There was improved documentation of referral to local and national databases. Most cases resulted in cancellation of surgery, and there were no patient deaths. A substantial increase in the number of patients with amoxicillin allergy was noted in the second time period, which was linked to a change in the local perioperative antibiotic policy.

CONCLUSIONS

Implementation of the AAGBI guidelines locally in a large hospital in 2008 resulted in an improved awareness of the importance of reporting and investigation of suspected anaphylaxis under anaesthesia. This tool was implemented coincidentally with the change in hospital antibiotic prophylaxis and enabled the cases detected to be accurately recorded and investigated. This led to a change in the hospital antibiotic policy for surgical prophylaxis. Implementation of structured guidance from a national anaesthesia organisation enhances recognition of the clinical features of anaphylaxis, increases number and completeness of referrals and more thorough immunological investigation, leading to improved patient safety during anaesthesia.

A critical incident report: Propofol triggered anaphylaxis

Although propofol is one of the most commonly used drugs for induction of anaesthesia, it is not devoid of anaphylactic potential. Early detection of any suspected anaphylactic reaction during anaesthesia, prompt management, identification of the offending agent and prevention of exposure to the offending agent in the future is the responsibility of the anaesthesiologist. This is a case report of anaphylaxis to propofol at the induction of anaesthesia in a previously non-allergic 56 year-old man, planned to undergo laparoscopic nephrectomy, who responded to epinephrine infusion.

Drug allergy: an updated practice parameter

Adverse drug reactions (ADRs) result in major health problems in the United States in both the inpatient and outpatient setting. ADRs are broadly categorized into predictable (type A and unpredictable (type B) reactions. Predictable reactions are usually dose dependent, are related to the known pharmacologic actions of the drug, and occur in otherwise healthy individuals, They are estimated to comprise approximately 80% of all ADRs. Unpredictable are generally dose independent, are unrelated to the pharmacologic actions of the drug, and occur only in susceptible individuals. Unpredictable reactions are subdivided into drug intolerance, drug idiosyncrasy, drug allergy, and pseudoallergic reactions. Both type A and B reactions may be influenced by genetic predisposition of the patient

Follow-up after anaesthetic anaphylaxis

background: the anaesthetic allergy clinic has been established at our institution for 30 years. Our practice has been to give patients a letter detailing the results of their investigations to pass on to subsequent anaesthetists. Our aims were to assess the adequacy of this letter in ensuring this vital communication, and to quantify the effectiveness of our recommendations on the safety of future anaesthesia.

METHODS

a project was undertaken to contact 606 previous clinic patients living in New South Wales by using last known addresses on our database, public telephone listing and local doctors. The review also involved collecting information, where available, about subsequent anaesthesia and the adequacy of information transfer about medications given safely or otherwise at this time.

RESULTS

of 606 patients, 246 were contactable. Of these, 183 had been anaesthetised subsequently, all safely. It was found that in only 11 cases had the patient's clinic letter been updated with the information from subsequent anaesthesia. We updated the letters of 82 patients with new information to improve the safety of drug selection for future anaesthesia.

CONCLUSIONS

although clinic testing allowed a high degree of safety in subsequent anaesthesia, it is evident that there is a need for systems to be implemented to improve the flow of patient anaesthetic allergy information after subsequent anaesthesia.

Rocuronium bromide induced anaphylaxis in a child -A case report-

Anaphylaxis or anaphylactoid reaction in pediatric patient during anesthesia is rare. We report a rocuronium induced anaphylactic reaction in a 33-month-old female. The patient was scheduled to undergo escharectomy due to injuries suffered from a major burn. Shortly after administration of rocuronium, the patient developed severe hypotension, tachycardia, and hypoxia. A similar reaction occurred after administration of rocuronium on subsequent anesthesia. She underwent uneventful anesthesia with volatile induction and maintenance of anesthesia with sevoflurane on her next 7 operations without using of muscle relaxant.