Prise en charge diagnostique des céphalées aiguës non traumatiques de l'adulte aux urgences du CHU de Rennes (une étude rétrospective sur 271 patients)

Introduction: les céphalées aiguës représentent un motif fréquent de consultation aux urgences. Bien que la plupart des patients présentent une cause bénigne de céphalée, une recherche soigneuse des céphalées symptomatiques d'une affection sous-jacente potentiellement grave, comme l'HSA, est indispensable. Méthode: il s'agit d'une étude rétrospective au SAU du CHU de Rennes, sur une période de 6 mois. Tous les patients présentant une céphalée aiguë non traumatique ont été inclus. L'objectif principal de l'étude était d'évaluer la prise en charge diagnostique des céphalées aiguës brutales non traumatiques au CHU de Rennes et sa conformité aux recommandations en vigueur. La prise en charge était considérée comme conforme quand le patient présentant une céphalée à risque d'HSA bénéficiait d'une TDM cérébrale suivie d'une PL si la TDM était normale ou bénéficiait d'une TDM cérébrale retrouvant une lésion expliquant la céphalée. Résultats: deux cent soixante et onze patients ont été inclus, dont 119 hommes (43,9%) de 37,3 +- 16,5 ans de moyenne d'âge. Une TDM était réalisée dans 45,4% des cas et une PL était réalisée dans 25,1 % des cas. Près d'un tiers des céphalées étaient considérées comme à risque d'HSA. La prise en charge diagnostique était considérée comme conforme dans 56,8% des cas. Conclusion: il n'existe actuellement pas de règles diagnostiques pouvant aider l'urgentiste à déterminer quels patients nécessiteraient des examens complémentaires. Nous avons établi un algorithme d'aide à la prescription d'examens complémentaires dans les céphalées aiguës.Introduction: Acute headaches are a common complaint in emergency department . Although most patients have a benign cause of their headache, a careful research of symptomatic headache for potentially life-threatening diseases, especially subarachnoid haemorrhage (SAH), is essential. Method: This is a retrospective study conducted in the emergency department of the university hospital of Rennes, for a period of 6 months. All non-traumatic acute headache patients were enrolled. The main objective of the study was to find out if the diagnostic strategy of nontraumatic acute headache at the University Hospital of Rennes was compliant with the recommendations. The strategy was considered as compliant when patients with suspected SAH undergo a head CT followed by a lumbar puncture (LP) if CT was negative or undergo a head CT which found a lesion explaining the headache. Results: Two hundred and seventy one patients were enrolled, of which 119 men (43.9%).The mean age was 37.3 +- 16.5 years. A CT was performed in 45.4% of the cases, a PL was performed in 25.1% of the cases. Almost one-third (29.9%)of all headaches were considered as being at risk of SAH and 56.8% of the diagnostic strategies were considered as compliant. Conclusion: there is currently no clinical decision rule that can help emergency physician to determine which patients would require diagnostic tests. We have created an algorithm to support the prescription of diagnostic tests in acute headaches.RENNES1-BU Santé (352382103) / SudocSudocFranceF

From fear to food: predation risk shapes deer behaviour, their resources and forest vegetation

The “ecology of fear” emphasizes the potential role of predation risk in shaping large herbivore behaviour and the way they affect forest ecology. In this study we show how the presence or absence of predation risk by hunters, together with or in the absence of carnivores, affect the behaviour and ecological effects of Sitka black-tailed deer introduced to the islands of Haida Gwaii, (British Columbia, Canada) or native to coastal BC. Deer in risk-free population showed remarkable tolerance to human presence while deer exposed to severe culling in the recent past, exhibited more costly anti-predator behaviors (long flight initiation distances and long travel distances when fleeing; reluctance to consume foreign bait or to investigate baited traps; increased night-time foraging) and were more likely to use exposed habitats. Contrasts in hunting histories translated into dramatic variation in the nature, distribution and abundance of the understory vegetation deer depended on.The experimental translocation of unwary deer from an island without hunting to an island where culls had partially restored the vegetation, showed that the lack of costly anti-predator behaviors was not significantly affected by the presence of abundant and higher quality forage. We interpreted these results as evidence that the experience of risk was key in explaining the observed behavioral contrasts between deer populations with different risk histories. We strengthened this conclusion by analysing the proportion of stable isotopes in deer bone collagen to show that deer foraged less in the exposed intertidal zone when predation risk was higher.Our results provide novel insights into how predation risk affects ecological networks, ecosystem complexity and animal behaviour. By revealing the role of key species, they may enable better strategies for future ecosystem restoration