The COVID-19 pandemic, which has been expanding since the first cases in Asia in late 2019, may result in acute respiratory failure (ARF) with severe hypoxemia [1-3]. In prehospital settings, the paucity of clinical respiratory signs has made assessing the severity of some COVID-19 patients challenging. Indeed, even though hypoxic ARF generally leads to an increase in respiratory rate (RR) [4], in some COVID-19 patients, a persistent normal RR was inconsistent with the severity of hypoxia. Based on retrospective data, we aimed to describe the discrepancy between prehospital initial RR (RRi) and initial SpO2 (Spo2i; i.e., before oxygen supplementation, FiO2 = 21%) in COVID-19 patients suffering from ARF. We retrospectively examined consecutive COVID-19 patients suffering from ARF who were treated by the Paris Fire Brigade's basic life-support (BLS) teams in the prehospital setting. Data were provided from primary home care providers. Based on a previous study [5], we used the SpO2i/RRi ratio as an estimator of the discrepancy insofar as a low numerator is associated with hypoxia, whereas a high denominator is typically associated with respiratory failure. After having measured the SpO2i/RRi values in COVID-19 patients, we compared them to those of non-COVID-19 patients (i.e., patients with other causes of ARF treated by the BLS teams over the previous 3 years in the same period). Continuous data were described as median (interquartile range) and were compared by applying the Kruskal-Wallis test. The French Society of Anaesthesia and

OBJECTIVE Blunt cerebrovascular injuries (BCVIs) affect approximately 1% of patients with blunt trauma. An antithrombotic or anticoagulation therapy is recommended to prevent the occurrence or recurrence of neurovascular events. This treatment has to be carefully considered after severe traumatic brain injury (TBI), due to the risk of intracranial hemorrhage expansion. Thus, the physician in charge of the patient is confronted with a hemorrhagic and ischemic risk. The main objective of this study was to determine the incidence of BCVI after severe TBI. METHODS The authors conducted a prospective, observational, single-center study including all patients with severe TBI admitted in the trauma center. Diagnosis of BCVI was performed using a 64-channel multidetector CT. Characteristics of the patients, CT scan results, and outcomes were collected. A multivariate logistic regression model was developed to determine the risk factors of BCVI. Patients in whom BCVI was diagnosed were treated with systemic anticoagulation. RESULTS In total, 228 patients with severe TBI who were treated over a period of 7 years were included. The incidence of BCVI was 9.2%. The main risk factors were as follows: motorcycle crash (OR 8.2, 95% CI 1.9-34.8), fracture involving the carotid canal (OR 11.7, 95% CI 1.7-80.9), cervical spine injury (OR 13.5, 95% CI 3.1-59.4), thoracic trauma (OR 7.3, 95% CI 1.1-51.2), and hepatic lesion (OR 13.3, 95% CI 2.1-84.5). Among survivors, 82% of patients with BCVI received systemic anticoagulation therapy, beginning at a median of Day 1.5. The overall stroke rate was 19%. One patient had an intracranial hemorrhagic complication. CONCLUSIONS Blunt cerebrovascular injuries are frequent after severe TBI (incidence 9.2%). The main risk factors are high-velocity lesions and injuries near cervical arteries.

The artery of Percheron is a solitary trunk representing an uncommon anatomic variant that provides bilateral arterial supply to the paramedian thalami and the rostral midbrain. Occlusion of this artery results in bilateral thalamic and mesencephalic infarctions. The clinical diagnosis is difficult because the complex anatomy causes large clinical variability. We report a case of a comatose patient with normal early head-computed tomography and magnetic resonance imaging. A bilateral paramedian thalamic infarct due to an occlusion of the artery of Percheron was revealed two days later by a new head computed tomography. To our knowledge, this is the first report in the literature of a symptomatic patient presenting an acute Percheron stroke with normal early brain magnetic resonance imaging. Our case indicates that a normal initial magnetic resonance imaging cannot formally eliminate the diagnosis of acute stroke of the artery of Percheron. We discuss the causes of noncontributive brain magnetic resonance imaging at the onset of this acute Percheron stroke and the alternative diagnosis and therapy methods.

Therapeutic, level IV.