Prescription-event monitoring (PEM) is the current gold standard for determining the risk of rare drug side-effects and comparing the risk between agents; however, spontaneous or prompted reporting schemes have low case-detection rates and exposure may be difficult to estimate. A novel method is described that allows a comparative adverse event rate between two drugs to be estimated-based on patterns of cross-reactivity-requiring only a sample of cases and no direct knowledge of drug exposure rates. Agreement was compared between the novel method and historical estimates of risk using PEM for comparative risk of rocuronium versus vecuronium anaphylaxis.
View Article and Find Full Text PDFBackground: A clinical scoring system to estimate the likelihood that a reaction represents a perioperative immediate hypersensitivity reaction has been devised using a Delphi consensus process. Agreement of this clinical scoring system with the outcome of allergological assessment would allow the use of this tool in post-resuscitation and subsequent management of suspected perioperative immediate hypersensitivity reaction and potentially as a new standard reference for clinical investigations.
Methods: We prospectively scored 301 cases of suspected perioperative immediate hypersensitivity reaction according to the Hypersensitivity Clinical Scoring Scheme.
Background: The observation that patients presenting for bariatric surgery had a high incidence of neuromuscular blocking agent (NMBA) anaphylaxis prompted this restricted case-control study to test the hypothesis that obesity is a risk factor for NMBA anaphylaxis, independent of differences in pholcodine consumption.
Methods: We compared 145 patients diagnosed with intraoperative NMBA anaphylaxis in Western Australia between 2012 and 2020 with 61 patients with cefazolin anaphylaxis with respect to BMI grade, history of pholcodine consumption, sex, age, comorbid disease, and NMBA type and dose. Confounding was assessed by stratification and binomial logistic regression.
Investigation of intraoperative anaphylaxis includes the exclusion of potential trigger agents the individual was exposed to within a plausible interval preceding the reaction. Occasionally, none of these agents will test positive. In this situation it is important to consider that excipients may be responsible for anaphylaxis, that the dilutions prepared to test the medication may not contain an appropriate concentration of the excipient to induce a positive skin reaction, or if an alternative formulation of the medication is tested, it may not contain the culprit excipient.
View Article and Find Full Text PDFSuspected perioperative allergic reactions are rare but can be life-threatening. The diagnosis is difficult to make in the perioperative setting, but prompt recognition and correct treatment is necessary to ensure a good outcome. A group of 26 international experts in perioperative allergy (anaesthesiologists, allergists, and immunologists) contributed to a modified Delphi consensus process, which covered areas such as differential diagnosis, management during and after anaphylaxis, allergy investigations, and plans for a subsequent anaesthetic.
View Article and Find Full Text PDFStandardising nomenclature facilitates diagnostic and therapeutic algorithms, improves comparisons of data in scientific research and reduces misunderstanding. Here, we propose a nomenclature for suspected perioperative allergic reactions.
View Article and Find Full Text PDFSuspected perioperative allergic reactions are often severe. To avoid potentially life-threatening re-exposure to the culprit drug, establishing a firm diagnosis and identifying the culprit is crucial. Drug provocation tests are considered the gold standard in drug allergy investigation but have not been recommended in the investigation of perioperative allergy, mainly because of the pharmacological effects of drugs such as induction agents and neuromuscular blocking agents.
View Article and Find Full Text PDFPerioperative hypersensitivity reactions (POH) constitute a clinical and diagnostic challenge, a consequence of heterogeneous clinical presentations, and multiple underlying pathomechanisms. POH do not necessarily involve an allergen-specific immune response with cross-linking of specific immunoglobulin E (sIgE) antibodies on mast cells and basophils. POH can also result from alternative specific and non-specific effector cell activation/degranulation such as complement-derived anaphylatoxins and off-target occupancy of mast cell, basophil, or both surface receptors.
View Article and Find Full Text PDFSuspected perioperative hypersensitivity reactions are rare but contribute significantly to the morbidity and mortality of surgical procedures. Recent publications have highlighted the differences between countries concerning the respective risk of different drugs, and changes in patterns of causal agents and the emergence of new allergens. This review summarises recent information on the epidemiology of perioperative hypersensitivity reactions, with specific consideration of differences between geographic areas for the most frequently involved offending agents.
View Article and Find Full Text PDFBackground: The propensities for the upper airway to collapse during anesthesia and sleep are related, although much of our understanding of this relationship has been inferred from clinical observation and indirect measures such as the apnea-hypopnea index. The aim of this study was to use an identical, rigorous, direct measure of upper airway collapsibility (critical closing pressure of the upper airway) under both conditions to allow the magnitude of upper airway collapsibility in each state to be precisely compared.
Methods: Ten subjects (8 men and 2 women; mean ± SD: age, 40.
A 50-year-old man developed a severe anaphylactic reaction shortly after the administration of sugammadex at the end of an uneventful laparoscopic appendectomy. Subsequent skin testing was negative to all agents to which the patient was exposed including sugammadex. Because of the temporal relationship to the administration of sugammadex, further skin testing was performed with premixed sugammadex and rocuronium that produced a markedly positive response.
View Article and Find Full Text PDFAnaphylactic reactions may be either of immune (allergy, usually IgE-mediated, sometimes IgG-mediated) or non-immune origin. The incidence of anaphylactic reactions during anaesthesia varies between countries ranging from 1/1250 to 1/18,600 per procedure. In France, the estimated incidence of allergic reactions is 100.
View Article and Find Full Text PDFCatheters that traverse the pharynx are often in place during clinical or research evaluations of upper airway function. The purpose of this study was to determine whether the presence of such catheters affects measures of upper airway collapsibility itself. To do so, pharyngeal critical closing pressure (Pcrit) and resistance upstream of the site of collapse Rus) were assessed in 24 propofol-anaesthetized subjects (14 men) with and without a multi-sensor oesophageal catheter (external diameter 2.
View Article and Find Full Text PDFNeuromuscular blocking agents (NMBAs) are the most commonly implicated drugs in IgE-mediated anaphylaxis during anaesthesia that can lead to perioperative morbidity and mortality. The rate of NMBA anaphylaxis shows marked geographical variation in patients who have had no known prior exposure to NMBAs, suggesting that there may be external or environmental factors that contribute to the underlying aetiology and pathophysiology of reactions. Substituted ammonium ions are shared among NMBAs and are therefore thought to be the main allergenic determinant of this class of drugs.
View Article and Find Full Text PDFJ Appl Physiol (1985)
August 2013
Increasing lung volume increases upper airway patency and decreases airway resistance and collapsibility. The role of diaphragm contraction in producing these changes remains unclear. This study was undertaken to determine the effect of selective diaphragm contraction, induced by phrenic nerve stimulation, on upper airway collapsibility and the extent to which any observed change was attributable to lung volume-related changes in pressure gradients or to diaphragm descent-related mediastinal traction.
View Article and Find Full Text PDFAnesthesia and sleep both predispose to upper airway obstruction through state-induced reductions in pharyngeal dilator muscle activation and lung volume. The tendencies are related in patients with obstructive sleep apnea commonly presenting with difficulties in airway management in the perioperative period. This is a period of great potential vulnerability for such patients because of compromise of the arousal responses that protect against asphyxiation during natural sleep.
View Article and Find Full Text PDFBackground: Upper airway collapsibility is known to increase under anesthesia. This study assessed how this increase in collapsibility evolves during slow Propofol induction and how it relates to anesthesia-induced changes in upper airway muscle activity and conscious state.
Methods: Nine healthy volunteers were studied.
Study Objectives: To determine the effect of head posture on upper airway collapsibility and site of collapse of the passive human upper airway.
Design: Pharyngeal critical closing pressure (Pcrit) and site of airway collapse were assessed during head flexion, extension and rotation in individuals undergoing propofol anesthesia.
Setting: Operating theatre of major teaching hospital.
Background: This study investigated the effect of varying concentrations of propofol on upper airway collapsibility and the mechanisms responsible for it.
Methods: Upper airway collapsibility was determined from pressure-flow relations at three concentrations of propofol anesthesia (effect site concentration = 2.5, 4.
Upper airway obstruction is common during both anaesthesia and sleep, as a result of loss of muscle tone present during wakefulness. Patients with obstructive sleep apnoea (OSA) are vulnerable during anaesthesia and sedation as the effects of loss of wakefulness are compounded by drug-induced depression of muscle activity and of arousal responses, so that they cannot respond to asphyxia. Conversely, those with 'difficult' airways during anaesthesia, either because of problems with maintenance of airway patency without tracheal intubation or because intubation itself is problematic, are at increased risk of OSA.
View Article and Find Full Text PDFUpper airway (UA) patency may be influenced by surface tension (gamma) operating within the (UAL). We examined the role of gamma of UAL in the maintenance of UA patency in eight isoflurane-anesthetized supine human subjects breathing via a nasal mask connected to a pneumotachograph attached to a pressure delivery system. We evaluated 1).
View Article and Find Full Text PDFBackground: The unprotected upper airway tends to obstruct during general anesthesia, yet its mechanical properties have not been studied in detail during this condition.
Methods: To study its collapsibility, pressure-flow relationships of the upper airway were obtained at three levels of anesthesia (end-tidal isoflurane = 1.2%, 0.