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.

Electroacupuncture reduced airway inflammation by activating somatosensory-sympathetic pathways in allergic asthmatic rats.

BACKGROUND: Electroacupuncture (EA) treatment is efficacious in patients with respiratory disorders, although the mechanisms of its action in lung-function protection are poorly understood. This study aimed to explore the neuroanatomical mechanisms of EA stimulation at the BL13 acupoint (Feishu, EA-BL13) improvement in asthma. METHODS: Allergic asthma was induced by intranasal 2.0% ovalbumin (OVA) instillation combined with intraperitoneal injection of the 10.0% OVA. The levels of interleukin (IL)-4 and IL-5 were detected by enzyme-linked immunosorbent assay. Hematoxylin and eosin and periodic acid-schiff stain were used to evaluate inflammatory cell infiltration and mucus secretion. Cellular oncogene fos induction in neurons after EA stimulation was detected by immunofluorescent staining. The mRNA expression levels of adrenergic receptors were quantified with real-time polymerase chain reaction. RESULTS: EA improved airway inflammation and mucus secretion mainly by activating somatosensory-sympathetic pathways (P <0.001). Briefly, the intermediolateral (IML) nuclei of the spinal cord received signals from somatic EA stimulation and then delivered the information via the sympathetic trunk to the lung. Excited sympathetic nerve endings in lung tissue released large amounts of catecholamines that specifically activated the ß2 adrenergic receptor (ß2AR) on T cells (P <0.01) and further decreased the levels of IL-4 and IL-5 (P <0.001) through the cyclic adenosine monophosphate/protein kinase A signaling pathway. CONCLUSION: This study provided a new explanation and clinical basis for the use of EA-BL13 as a treatment for allergic asthma in both the attack and remission stages and other respiratory disorders related to airway inflammation.

Microglial Nrf2/HO-1 signaling gates remifentanil-induced hyperalgesia via suppressing TRPV4-mediated M1 polarization.

Remifentanil-induced hyperalgesia (RIH) represents a significant clinical challenge due to the widespread use of opioids in pain management. However, the molecular and cellular mechanisms underlying RIH remain elusive. This study aimed to unravel the role of spinal cord microglia, focusing on the Nrf2/HO-1 signaling pathway and TRPV4 channels in the development of RIH. We used both in vivo and in vitro models to investigate the activation state of spinal cord microglia, the expression of TRPV4 channels, and the modulation of the Nrf2/HO-1 pathway under remifentanil exposure. In addition, we evaluated the potential therapeutic effects of dexmedetomidine, a perioperative α2-adrenergic agonist, on RIH and its related molecular pathways. Our results revealed a prominent role of spinal cord microglia in RIH, demonstrating an apparent microglial M1 polarization and increased TRPV4 channel expression. A notable observation was the downregulation of the Nrf2/HO-1 pathway, which was associated with increased neuroinflammation and mechanical allodynia. By upregulating or overexpressing Nrf2, we confirmed its ability to inhibit TRPV4 and thereby attenuate RIH-associated mechanical allodynia, M1 polarization, and neuroinflammation. Encouragingly, dexmedetomidine demonstrated therapeutic potential by positively modulating the Nrf2-TRPV4 nexus, attenuating mechanical allodynia, and reducing microglial inflammation. Our research highlights the critical role of spinal cord microglia in RIH mediated by the Nrf2-TRPV4 axis. The ability of dexmedetomidine to modulate this axis suggests its potential as an adjunctive therapy to remifentanil in mitigating RIH. Further studies are imperative to explore the broader implications and practical applicability of our findings.

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.

Effect of personality traits on rehabilitation effect after anterior cruciate ligament reconstruction: An observational study.

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction requires an extended period of postoperative rehabilitation. Psychological factors can affect recovery after surgery. Study of psychological factors is still limited to self-motivation, fear and pain. Study of personality traits associated with early rehabilitation outcome after ACL reconstruction is scarce. OBJECTIVE: We aimed to explore the effect of personality traits on early rehabilitation after ACL reconstruction and provide a reference for clinicians in designing a personalized rehabilitation plan. METHODS: This prospective analysis investigated 155 patients at 3 and 6 months after ACL reconstruction. Follow-up involved administration of a general data questionnaire, the Chinese Big Five Personality Inventory Brief Version, the Tegner activity score, the International Knee Documentation Committee Subjective Knee Score, the Knee injury and Osteoarthritis Outcome Score, the Lysholm Score and a balance test. RESULTS: Among the 155 patients included (124 males), Neuroticism was negatively correlated with subjective knee scores at 3 and 6 months after surgery (p<0.001). The odds of a poor balance test result was increased for each 1-point increase in Neuroticism score (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.28-2.36, p<0.001). We found a positive correlation between Conscientiousness score and subjective knee scores at 3 and 6 months after surgery (p<0.001). For every 1-point increase in Conscientiousness score, the odds of a poor balance test result were decreased (OR 0.29, 95% CI 0.16-0.54, p<0.001). Agreeableness and Openness to experience scores were positively correlated with subjective knee scores at 3 and 6 months after surgery (p<0.001). We found no correlation between Extraversion and subjective knee scores at 3 and 6 months after surgery (p>0.05) but a positive correlation with the Tegner activity score at 3 and 6 months after surgery (p<0.05). CONCLUSION: We found a significant correlation between the Big Five personality dimensions and the early rehabilitation effect after ACL reconstruction, which can provide a reference for clinicians in designing a personalized rehabilitation plan.