[Contrast medium: an unpredictable ally]. / Produit de contraste : un allié imprévisible.

Reactions to contrast media are unpredictable. This article examines the use of iodinated and gadolinium-based contrast agents in medical imaging. It explores their clinical presentation, associated risk factors, precautions prior to their administration, and treatment options in the event of a reaction. By highlighting these essential aspects, the article aims to inform healthcare professionals on the safe and effective management of these agents during imaging procedures. The effectiveness of the different premedication protocols proposed in the literature has not yet been established. In particular, premedication does not prevent serious allergic reactions.

Les réactions aux produits de contraste sont imprévisibles. Cet article examine l'utilisation des agents de contraste iodés et à base de gadolinium en imagerie médicale. Il explore la présentation clinique de leurs réactions, les facteurs de risque, les précautions préalables à leur administration et les options de traitement en cas de réaction. En mettant en lumière ces aspects essentiels, l'article vise à informer les professionnels de la santé sur la gestion sécuritaire et efficace de ces agents lors des procédures d'imagerie. L'efficacité des différents protocoles de prémédication proposés dans la littérature n'est pas établie. En particulier, la prémédication ne prévient pas les réactions allergiques graves.

[Interprofessional simulation in emergency medicine]. / Simulation interprofessionnelle en médecine d'urgence.

Teamwork is essential in emergency medicine, but in practice it can be polluted by communication difficulties, a lack of understanding of everyone's roles and responsibilities, and a discordant definition of operating methods and objectives. Today, there is a strong awareness of the need to train medical and healthcare teams in interprofessional collaborative practice to learn how to work as a team, reduce medical errors and improve patient safety. Simulation is a recognized and effective pedagogical modality for achieving these objectives. It is now permanently established in pre- and postgraduate medical-nursing training courses in emergency medicine.

Le travail en équipe est indispensable en médecine d'urgence mais, dans la pratique, il peut être pollué par des difficultés de communication, une méconnaissance des rôles et responsabilités de chacun, et une définition discordante des modes de fonctionnement et des objectifs. Aujourd'hui, il y a une forte prise de conscience de la nécessité de former les équipes médico­soignantes à la pratique collaborative interprofessionnelle pour apprendre à travailler en équipe, réduire les erreurs médicales et améliorer la sécurité des patient-e-s. La simulation est une modalité pédagogique reconnue et efficace pour atteindre ces objectifs. Elle est désormais implantée de façon pérenne dans les cursus de formation médico-soignante pré et postgraduée en médecine d'urgence.

PLUS-IS-LESS project: Procalcitonin and Lung UltraSonography-based antibiotherapy in patients with Lower rESpiratory tract infection in Swiss Emergency Departments: study protocol for a pragmatic stepped-wedge cluster-randomized trial.

BACKGROUND: Lower respiratory tract infections (LRTIs) are among the most frequent infections and a significant contributor to inappropriate antibiotic prescription. Currently, no single diagnostic tool can reliably identify bacterial pneumonia. We thus evaluate a multimodal approach based on a clinical score, lung ultrasound (LUS), and the inflammatory biomarker, procalcitonin (PCT) to guide prescription of antibiotics. LUS outperforms chest X-ray in the identification of pneumonia, while PCT is known to be elevated in bacterial and/or severe infections. We propose a trial to test their synergistic potential in reducing antibiotic prescription while preserving patient safety in emergency departments (ED). METHODS: The PLUS-IS-LESS study is a pragmatic, stepped-wedge cluster-randomized, clinical trial conducted in 10 Swiss EDs. It assesses the PLUS algorithm, which combines a clinical prediction score, LUS, PCT, and a clinical severity score to guide antibiotics among adults with LRTIs, compared with usual care. The co-primary endpoints are the proportion of patients prescribed antibiotics and the proportion of patients with clinical failure by day 28. Secondary endpoints include measurement of change in quality of life, length of hospital stay, antibiotic-related side effects, barriers and facilitators to the implementation of the algorithm, cost-effectiveness of the intervention, and identification of patterns of pneumonia in LUS using machine learning. DISCUSSION: The PLUS algorithm aims to optimize prescription of antibiotics through improved diagnostic performance and maximization of physician adherence, while ensuring safety. It is based on previously validated tests and does therefore not expose participants to unforeseeable risks. Cluster randomization prevents cross-contamination between study groups, as physicians are not exposed to the intervention during or before the control period. The stepped-wedge implementation of the intervention allows effect calculation from both between- and within-cluster comparisons, which enhances statistical power and allows smaller sample size than a parallel cluster design. Moreover, it enables the training of all centers for the intervention, simplifying implementation if the results prove successful. The PLUS algorithm has the potential to improve the identification of LRTIs that would benefit from antibiotics. When scaled, the expected reduction in the proportion of antibiotics prescribed has the potential to not only decrease side effects and costs but also mitigate antibiotic resistance. TRIAL REGISTRATION: This study was registered on July 19, 2022, on the ClinicalTrials.gov registry using reference number: NCT05463406. TRIAL STATUS: Recruitment started on December 5, 2022, and will be completed on November 3, 2024. Current protocol version is version 3.0, dated April 3, 2023.