Muscle relaxants allergy

Epidemiology and Triggers of Severe Perioperative Anaphylaxis: An 8-Year Single-Center Study

OBJECTIVE

To determine the features, rescue measures, outcomes, re-allergic reactions, and independent risk factors associated with severe anaphylaxis during surgery.

DESIGN

Instances of severe perioperative anaphylaxis were identified through perioperative electronic records, adverse event reporting records, and surveys of anesthesiologists. Confirmed cases were randomly matched 4:1 with control cases on the same operation day. Patient risk factors, surgery type, anesthetic technique, and perioperative medications, fluids, and blood transfusions were given in instances of severe perioperative anaphylaxis were compared with control cases.

SETTING

A tertiary hospital in China.

PATIENTS

All patients undergoing surgery and anesthesia in the operating room from January 2014 to February 2022.

MEASUREMENTS

Incidence and the independent risk factors for severe perioperative anaphylaxis.

MAIN RESULTS

Ninety-seven patients experienced severe perioperative allergic responses during the 266,033 surgeries performed, with an incidence rate of 3.6 per 10,000. Three of 97 anaphylaxis patients experienced a severe allergic reaction again during the second surgery. The nested case-control study revealed that the independent triggers during surgery were allergy history (odds ratio 5.23; 95% confidence interval [CI], 2.35-11.68; p < 0.001), cisatracurium use (odds ratio 5.03; 95% CI, 1.22-20.70; p < 0.001), hydroxyethyl starch 130/0.4 use (odds ratio 5.36; 95% CI, 2.99-9.60; p =0.025), and allogeneic plasma (odds ratio 11.02; 95% CI, 3.78-35.95; p < 0.001).

CONCLUSIONS

Perioperative severe anaphylaxis is a rare but life-threatening complication. Previous allergic history, cisatracurium, hydroxyethyl starch 130/0.4, and allogeneic plasma may be the independent triggers. Early diagnosis of anaphylaxis and the timely administration of epinephrine are critical to allergic treatment. Avoiding exposure to allergens is effective for preventing severe allergic responses and the efficacy of glucocorticoids and antihistamines is controversial.

Atracurium-Induced Bronchospasm With Flat Capnograph at Induction of General Anaesthesia: A Case Report

Benzylisoquinolinium neuromuscular blocking agents can precipitate bronchospasm either through allergy/anaphylaxis or isolated stimulation of mast cell histamine release. This report presents a 75-year-old female who attended the day surgery unit for a rigid cystoscopy under general anaesthesia. She had a hyper-reactive airway history of mild historic asthma and sensitivity to aerosols. After administration of atracurium at induction of anaesthesia, ventilation became challenging with no chest rise and a flat CO2 trace. Repeat video laryngoscopy confirmed correct endotracheal tube position. The patient remained cardiovascularly stable with no mucocutaneous signs of anaphylaxis. Administration of high flow oxygen, sevoflurane, salbutamol and magnesium sulfate led to gradual improvement and normalisation of respiratory parameters. Surgery was postponed. This report highlights atracurium as an important trigger of bronchospasm at induction of anaesthesia, and illustrates that in rare cases a flat capnograph does not always indicate a mispositioned airway device. Several aspects of the anaesthetic plan for this patient were suboptimal given her respiratory history, namely, the choice of mode of anaesthesia and choice of neuromuscular blocking agent. These factors are discussed in the context of anaesthetic planning for patients presenting with features suggesting high bronchospastic risk.

Azemiopsin, a Selective Peptide Antagonist of Muscle Nicotinic Acetylcholine Receptor: Preclinical Evaluation as a Local Muscle Relaxant

Azemiopsin (Az), a linear peptide from the Azemiops feae viper venom, contains no disulfide bonds, is a high-affinity and selective inhibitor of nicotinic acetylcholine receptor (nAChR) of muscle type and may be considered as potentially applicable nondepolarizing muscle relaxant. In this study, we investigated its preclinical profile in regard to in vitro and in vivo efficacy, acute and chronic toxicity, pharmacokinetics, allergenic capacity, immunotoxicity and mutagenic potency. The peptide effectively inhibited (IC50 ~ 19 nM) calcium response of muscle nAChR evoked by 30 μM (EC100) acetylcholine but was less potent (IC50 ~ 3 μM) at α7 nAChR activated by 10 μM (EC50) acetylcholine and had a low affinity to α4β2 and α3-containing nAChR, as well as to GABAA or 5HT₃ receptors. Its muscle relaxant effect was demonstrated at intramuscular injection to mice at doses of 30-300 µg/kg, 30 µg/kg being the initial effective dose and 90 µg/kg-the average effective dose. The maximal muscle relaxant effect of Az was achieved in 10 min after the administration and elimination half-life of Az in mice was calculated as 20-40 min. The longest period of Az action observed at a dose of 300 µg/kg was 55 min. The highest acute toxicity (LD50 510 μg/kg) was observed at intravenous injection of Az, at intramuscular or intraperitoneal administration it was less toxic. The peptide showed practically no immunotoxic, allergenic or mutagenic capacity. Overall, the results demonstrate that Az has good drug-like properties for the application as local muscle relaxant and in its parameters, is not inferior to the relaxants currently used. However, some Az modification might be effective to extend its narrow therapeutic window, a typical characteristic and a weak point of all nondepolarizing myorelaxants.

Anaphylaxis from atracurium without skin manifestation

Anaphylaxis is an acute, potentially fatal allergic reaction involving multi organ system that is triggered by a wide range of antigens with a subsequent release of chemical mediators from mast cells and basophils. Diagnosis is primarily clinical though laboratory studies are helpful in further confirmation. Anaphylactic reactions during anesthesia are rare, but can be fatal if not promptly recognized and treated. Among all drugs commonly used in anesthesia, muscle relaxants are the most notorious to trigger anaphylactic reactions and benzylisoquinolinium group of drugs are known to be less common an offender than the steroidal compounds. We report severe anaphylactic reaction after administration of atracurium that was promptly diagnosed and managed without any further morbidity.