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Summary: Videolaryngoscopy is a suitable alternative to flexible bronchoscopy to facilitate awake tracheal intubation. The relative effectiveness of these techniques in clinical practice is unknown. We compared flexible nasal bronchoscopy with Airtraq® videolaryngoscopy in patients with an anticipated difficult airway scheduled for awake tracheal intubation. Patients were allocated randomly to flexible nasal bronchoscopy or videolaryngoscopy. All procedures were performed with upper airway regional anaesthesia blockade and a target‐controlled intravenous infusion of remifentanil. The success rate with the allocated technique was the primary outcome. A non‐inferiority analysis with a predefined limit of 8% was planned. Seventy‐eight patients were recruited, allocated randomly and analysed. The rate of successful intubation was 97% and 82% in the flexible bronchoscopy and videolaryngoscopy groups, respectively, p = 0.032. The median (IQR [range]) time to tracheal intubation was shorter with the Airtraq, 163 (105–332 [40–1004]) vs. 217 (180–364 [120–780]) s, p = 0.030. There were no significant differences for complications found between the groups. The median visual analogue scale for ease of intubation was 8 (7–9 [0–10]) for Airtraq vs. 8 (7–9 [0–10]) for flexible bronchoscopy, p = 0.710. The median visual analogue scale for patient comfort for Airtraq was 8 (6–9 [2–10]) vs. 8 (7–9 [3–10]) for flexible bronchoscopy, p = 0.370. The Airtraq videolaryngoscope is not non‐inferior to flexible bronchoscopy for awake tracheal intubation in a clinical setting when awake tracheal intubation is indicted. It may be a suitable alternative when judged on a case‐by‐case basis. [ABSTRACT FROM AUTHOR]

Background: To reduce the number of deaths caused by exsanguination, the initial management of severe trauma aims to prevent, if not limit, the lethal triad, which consists of acidosis, coagulopathy, and hypothermia. Recently, several studies have suggested adding hypocalcemia to the lethal triad to form the lethal diamond, but the evidence supporting this change is limited. Therefore, the aim of this study was to compare the lethal triad and lethal diamond for their respective associations with 24-h mortality in severe trauma patients receiving transfusion., Methods: We performed a multicenter retrospective analysis of patients in TraumaBase®, a French database (2011-2023). The patients included in this study were all trauma patients who had received transfusions of at least 1 unit of red blood cells (RBCs) within the first 6 h of hospital admission and for whom ionized calcium measurements were available. Hypocalcemia was defined as an ionized calcium level < 1.1 mmol/L., Results: A total of 2141 severe trauma patients were included (median age: 39, interquartile range [IQR]: 26-57; median injury severity score: 27, IQR: 17-41). Patients primarily presented with blunt trauma (81.7%), and a 24-h mortality rate of 16.1% was observed. Receiver operating characteristic curve analysis revealed no significant difference in the association with 24-h mortality between the lethal diamond (area under the curve [AUC]: 0.71) and the lethal triad (AUC: 0.72) (p = 0.26). The strength of the association with 24-h mortality was similar between the lethal triad and the lethal diamond, with Cramer's V values of 0.29 and 0.28, respectively., Conclusions: This study revealed no significant difference between the lethal triad and the lethal diamond in terms of their respective associations with 24-h mortality in severe trauma patients requiring transfusion. These results raise questions about the independent role of hypocalcemia in early mortality., Competing Interests: Declarations. Ethics approval and consent to participate: TraumaBase® obtained approval from the Advisory Committee for Information Processing in Health Research (CCTIRS) from the National Commission for Data Protection (CNIL) and meets national institutional review board requirements (Comité de Protection des Personnes, Paris VI, Paris, France). Data are anonymized upon collection in case report files. This study received ethical approval (CER Paris Nord, Institutional Review Board number 00006477) and was declared to the CNIL (Authorization Number 2234099). Consent for publication: Not applicable. Competing interests: Marc Leone served as a consultant for Viatris, Edwards, AOP Pharma, and MSD. Julien Pottecher for LFB. All the other authors have no conflicts of interest in relation to the submitted study., (© 2024. The Author(s).)

Purpose: Intraoperative alveolar recruitment maneuvers (ARM) used during protective ventilation strategy may have severe adverse hemodynamic effects, reported mainly during abrupt continuous positive airway pressure (CPAP). Stepwise increase and decrease in positive end expiratory pressure (PEEP) may be used. We compared the hemodynamic effects of these two maneuvers., Methods: We enrolled patients scheduled for intermediate to high-risk surgery with continuous arterial pressure and stroke volume (esophageal Doppler) monitoring in a prospective, single-centre, randomized, double-blind study. After induction of anesthesia, we ensured preload independence of stroke volume before an ARM was randomly performed: 30 cm H 2 O CPAP for 30 sec (CPAP group) or stepwise increase in PEEP from 8 to 20 cm H 2 O with inspiratory pressure of 10 cm H 2 O followed by a stepwise decrease in PEEP from 20 to 8 cm H 2 O (STEP group). The primary outcome was the relative variation in stroke volume., Results: Thirty-five patients were included in the CPAP and STEP groups. Mean (standard deviation) relative variation in stroke volume was -57 (24)% in the CPAP group and -32 (24)% in the STEP group (difference, -25; 95% confidence interval, -37 to -14; P < 0.001). Changes in systolic, mean, and diastolic arterial pressure over time were not different between groups. The ARM was stopped because of a systolic arterial pressure < 70 mm Hg in four patients in the CPAP group and in one patient in the STEP group., Conclusions: Alveolar recruitment maneuvers through stepwise increase and decrease in PEEP have a better hemodynamic tolerance than transient CPAP., Trial Registration: ClinicalTrials.gov (NCT04802421); first submitted 15 March 2021., (© 2023. Canadian Anesthesiologists' Society.)

Individuals use the observation of a conspecific to learn new behaviors and skills in many species. Whether observational learning is affected in epilepsy is not known. Using the pilocarpine rat model of epilepsy, we assessed learning by observation in a spatial task. The task involves a naive animal observing a demonstrator animal seeking a reward at a specific spatial location. After five observational sessions, the observer is allowed to explore the rewarded space and look for the reward. Although control observer rats succeed in finding the reward when allowed to explore the rewarded space, epileptic animals fail. However, epileptic animals are able to successfully learn the location of the reward through their own experience after several trial sessions. Thus, epileptic animals show a clear deficit in learning by observation. This result may be clinically relevant, in particular in children who strongly rely on observational learning., (© 2022 The Authors. Epilepsia published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)

Interactions between conspecifics are central to the acquisition of useful memories in the real world. Observational learning, i.e., learning a task by observing the success or failure of others, has been reported in many species, including rodents. However, previous work in rats with NMDA-receptor blockade has shown that even extensive observation of an unexplored space through a clear barrier is not sufficient to generate a stable hippocampal representation of that space. This raises the question of whether rats can learn a spatial task in a purely observed space from watching a conspecific, and if so, does this somehow stabilize their hippocampal representation? To address these questions, we designed an observational spatial task in a two-part environment that is nearly identical to that of the aforementioned electrophysiological study, in which an observer rat watches a demonstrator animal to learn the location of a hidden reward. Our results demonstrate that rats do not need to physically explore an environment to learn a reward location, provided a conspecific demonstrates where it is. We also show that the behavioral memory is not affected by NMDA receptor blockade, suggesting that the spatial representation underlying the behavior has been consolidated by observation alone., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Doublet, Nosrati and Kentros.)

Organic electrochemical transistors are integrated on depth probes to achieve localized electrical stimulation of neurons. The probes feature a mechanical delamination process which leaves only a 4 μm thick film with embedded transistors inside the brain. This considerably reduces probe invasiveness and correspondingly improves future brain-machine interfaces., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In vivo electrophysiological recordings of neuronal circuits are necessary for diagnostic purposes and for brain-machine interfaces. Organic electronic devices constitute a promising candidate because of their mechanical flexibility and biocompatibility. Here we demonstrate the engineering of an organic electrochemical transistor embedded in an ultrathin organic film designed to record electrophysiological signals on the surface of the brain. The device, tested in vivo on epileptiform discharges, displayed superior signal-to-noise ratio due to local amplification compared with surface electrodes. The organic transistor was able to record on the surface low-amplitude brain activities, which were poorly resolved with surface electrodes. This study introduces a new class of biocompatible, highly flexible devices for recording brain activity with superior signal-to-noise ratio that hold great promise for medical applications.

Objective: One cornerstone event during epileptogenesis is the occurrence of the first spontaneous seizure (SZ1). It is therefore important to identify biomarkers of the network alterations leading to SZ1. In experimental models of temporal lobe epilepsy (TLE), interictal-like activity (ILA) precedes SZ1 by several days. The goal of this study was to determine whether ILA dynamics bore electrophysiological features signaling the impeding transition to SZ1., Methods: Experimental TLE was triggered by pilocarpine- or kainic acid-induced status epilepticus (SE). Continuous electroencephalographic recordings were performed 7 days before and up to 40 days after SE. The amplitude and duration of the spike and wave components of interictal spikes were analyzed., Results: Two types of interictal spikes were distinguished: type 1, with a spike followed by a long-lasting wave, and type 2, with a spike without wave. The number, amplitude, and duration of type 1 spikes started to decrease, whereas the number of type 2 spikes increased, several days before SZ1, reaching their minimum/maximum values just before SZ1., Interpretation: The change in ILA pattern could constitute a predictive biomarker of SZ1. The mechanisms underlying these dynamic modifications and their functional impact are discussed in the context of the construction of an epileptogenic network., (Copyright © 2012 American Neurological Association.)