Impact of emergency medical helicopter transport directly to a university hospital trauma center on mortality of severe blunt trauma patients until discharge

International audienceIntroductionThe benefits of transporting severely injured patients by helicopter remain controversial. This study aimed to analyze the impact on mortality of helicopter compared to ground transport directly from the scene to a University hospital trauma center.MethodsThe French Intensive Care Research for Severe Trauma cohort study enrolled 2,703 patients with severe blunt trauma requiring admission to University hospital intensive care units within 72 hours. Pre-hospital and hospital clinical data, including the mode of transport, (helicopter (HMICU) versus ground (GMICU), both with medical teams), were recorded. The analysis was restricted to patients admitted directly from the scene to a University hospital trauma center. The main endpoint was mortality until ICU discharge.ResultsOf the 1,958 patients analyzed, 74% were transported by GMICU, 26% by HMICU. Median injury severity score (ISS) was 26 (interquartile range (IQR) 19 to 34) for HMICU patients and 25 (IQR 18 to 34) for GMICU patients. Compared to GMICU, HMICU patients had a higher median time frame before hospital admission and were more intensively treated in the pre-hospital phase. Crude mortality until hospital discharge was the same regardless of pre-hospital mode of transport. After adjustment for initial status, the risk of death was significantly lower (odds ratio (OR): 0.68, 95% confidence interval (CI) 0.47 to 0.98, P = 0.035) for HMICU compared with GMICU. This result did not change after further adjustment for ISS and overall surgical procedures.ConclusionsThis study suggests a beneficial impact of helicopter transport on mortality in severe blunt trauma. Whether this association could be due to better management in the pre-hospital phase needs to be more thoroughly assessed

Slower Is Higher: Threshold Modulation of Cortical Activity in Voluntary Control of Breathing Initiation

Speech or programmed sentences must often be interrupted in order to listen to and interact with interlocutors. Among many processes that produce such complex acts, the brain must precisely adjust breathing to produce adequate phonation. The mechanism of these adjustments is multifactorial and still poorly understood. In order to selectively examine the adjustment in breath control, we recorded respiratory-related premotor cortical potentials from the scalp of human subjects while they performed a single breathing initiation or inhibition task. We found that voluntary breathing is initiated if, and only if, the cortical premotor potential activity reaches a threshold activation level. The stochastic variability in the threshold correlates to the distribution of initiation times of breathing. The data also fitted a computerized interactive race model. Modeling results confirm that this model is also as effective in respiratory modality, as it has been found to be for eye and hand movements. No modifications were required to account for respiratory cycle inhibition processes. In this overly simplified task, we showed a link between voluntary initiation and control of breathing and activity in a fronto-median region of the cerebral cortex. These results shed light on some of the physiological constraints involved in the complex mechanisms of respiration, phonation, and language

induction non-invasive d'une plasticité de la commande ventilatoire chez l'humain sain

La commande de la ventilation chez l'humain est capable d'adaptation persistante qui repose sur des mécanismes de type LTP. Différentes techniques permettant l'induction de plasticité sont couramment utilisées mais leur application au contrôle ventilatoire n'a fait l'objet que de très peu de travaux.L'objectif de cette thèse est (1) examiner la possibilité d'induire des mécanismes de type LTP par la rTMS et la tsDCS en deux sites de la commande ventilatoire destinée au diaphragme, l'AMS et les métamères C3-C5 ; (2) évaluer les conséquences sur le profil ventilatoire en ventilation de repos et lorsque la ventilation est artificiellement contrainte. Nous avons examiné les effets d'un conditionnement inhibiteur appliqué par rTMS en regard de l'AMS sur l'excitabilité corticophrénique. Nous avons observé la présence d'une diminution persistante de cette excitabilité et en avons tiré la proposition qu'en ventilation de repos l'AMS augmente l'excitabilité de la commande ventilatoire à l'éveil. Nous avons alors considéré les conséquences de la rTMS sur la ventilation expérimentalement contrainte. Les modifications du profil ventilatoire induites par la rTMS sont en faveur d'une participation de l'AMS à la production ou au traitement de la copie d'efférence. Dans une 3ème étude, nous avons examiné les effets de la tsDCS au niveau C3-C5 sur l'excitabilité corticophrénique et sur le profil ventilatoire. L'augmentation de cette excitabilité et du volume courant nous a conduit à suggérer la possibilité d'induire une plasticité respiratoire au niveau spinal.L'ensemble de ces résultats nous permet d'envisager des perspectives thérapeutiques à l'utilisation de la rTMS et de la tsDCS.A salient feature of the ventilatory control system is its ability to persistently adapt its behaviour. This stems from long-term plasticity mechanisms similar to those described for the neural control in general. Plasticity can be induced by various non-invasive stimulation techniques(e.g. rTMS, TDCS, tsDCS) that are commonly used but have not be systematically applied to ventilatory plasticity. The aim of this thesis is twofold: (1) to examine the possibility of inducing LTP by rTMS and tsDCS at two sites of the ventilatory control system, namely the SMA and the phrenic motoneurons: (2) to evaluate the impact of such plasticity on breathing pattern during spontaneous ventilation and inspiratory threshold loading. We examined the effects of an inhibitory rTMS paradigm applied to the SMA on corticophrenic excitability. We observed a persistent decrease in corticophrenic excitability and therefore proposed that the SMA participates in the increased resting state of the ventilatory motor system during wake. Then we considered the consequences of rTMS on breathing pattern during ITL. The corresponding modifications support a contribution of the SMA to the production or processing of an ventilatory efference copy. In a third study, we examined the effects of a tsDCS delivered to C3-C5 on the corticophrenic excitability and on the respiratory pattern. Increased corticophrenic excitability and tidal volume were observed. This suggests that respiratory plasticity takes place at the spinal level. Taken together, these results open the perspective of harnessing respiratory plasticity as a therapeutic tool in disorders altering the ventilatory command.PARIS-JUSSIEU-Bib.électronique (751059901) / SudocSudocFranceF

Infrastructure for Detector Research and Development towards the International Linear Collider

The EUDET-project was launched to create an infrastructure for developing and testing new and advanced detector technologies to be used at a future linear collider. The aim was to make possible experimentation and analysis of data for institutes, which otherwise could not be realized due to lack of resources. The infrastructure comprised an analysis and software network, and instrumentation infrastructures for tracking detectors as well as for calorimetry.Comment: 54 pages, 48 picture

Inspiratory resistances facilitate the diaphragm response to transcranial stimulation in humans

BACKGROUND: Breathing in humans is dually controlled for metabolic (brainstem commands) and behavioral purposes (suprapontine commands) with reciprocal modulation through spinal integration. Whereas the ventilatory response to chemical stimuli arises from the brainstem, the compensation of mechanical loads in awake humans is thought to involve suprapontine mechanisms. The aim of this study was to test this hypothesis by examining the effects of inspiratory resistive loading on the response of the diaphragm to transcranial magnetic stimulation. RESULTS: Six healthy volunteers breathed room air without load (R0) and then against inspiratory resistances (5 and 20 cmH(2)O/L/s, R5 and R20). Ventilatory variables were recorded. Transcranial magnetic stimulation (TMS) was performed during early inspiration (I) or late expiration (E), giving rise to motor evoked potentials (MEPs) in the diaphragm (Di) and abductor pollicis brevis (APB). Breathing frequency significantly decreased during R20 without any other change. Resistive breathing had no effect on the amplitude of Di MEPs, but shortened their latency (R20: -0.903 ms, p = 0.03) when TMS was superimposed on inspiration. There was no change in APB MEPs. CONCLUSION: Inspiratory resistive breathing facilitates the diaphragm response to TMS while it does not increase the automatic drive to breathe. We interpret these findings as a neurophysiological substratum of the suprapontine nature of inspiratory load compensation in awake humans

Steady state visual evoked potentials-based patient interface under breathingconstraints

International audienceSteady state visual evoked potentials (SSVEP)have been widely utilized in brain computer interfacing (BCI)in last years. In this paper, we present a study exploringthe possibilities of SSVEP to manage the communicationbetween patients suffering respiratory disorders and healthcare providers. By imposing different breathing constraints,five healthy subjects communicated their breathing sensations(breathing well/breathing bad) using a visual frequency taggingparadigm: two visual stimuli with different flickeringfrequencies (15 and 20 Hz) were simultaneously presented ona screen. Using electroencephalographic (EEG) signals fromonly three EEG electrodes, two spectral features were extractedby a spatial filter in a sliding window, then classified by anunsupervised algorithm based on k-medians. Average detectionsuccess rates were of 70% during breathing discomfort, andof 83% when subjects breathed comfortably. Results suggestthat SSVEP-based BCI may be a promising choice to improvepatient-caregiver communication in situations of breathingdiscomfort when verbal communication is difficul

La filiacion y la fecundacion "in vitro"

Las tecnicas de reproduccion asistida no solo representan una solucion para ayudar a superar problemas de esterilidad, sino que su practica conlleva problemas eticos y juridicos. Esta Tesis analiza los problemas que plantea la fecundacion "in vitro", desde el punto de vista de la filiacion, para determinar la paternidad y maternidad cuando se utilizan los gametos de la pareja o de un tercero. Desde este punto de vista, se estudian la situacion juridica del tercero -llamado donante- y de las madres subrogadas, asi como las acciones de filiacion Tambien se examina la problematica que plantea la congelacion de semen y embriones, al poder un hombre engendrar un hijo despues de muerto. Entre las fuentes que se analizan estan los principales informes extranjeros que han estudiado la problematica de estas tecnicas, asi como el Informe especial de..