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Speed e-bikes are electrically assisted pedal cycles with a speed of up to 45 km/h. Because of their high speed, these vehicles are not classified as bicycles in the European Union. However, their external aspect and their mode of propulsion—the user needs to pedal for the electric assistance to work—make them part of the symbolic universe of bicycles. This raises the following question: should these vehicles ride on cycle lanes, or on the road? The authors argue that answering this question implies understanding both how these vehicles are used, and how speed e-bike users perceive themselves. How do users experience their high-velocity bikes? Using qualitative interviews with speed e-bike users in France, Belgium, and Switzerland, this research offers novel data on the actual usage of this emerging mode of transport and what it represents symbolically to users. Results show that speed e-bike users consider themselves as cyclists and value the opportunity to ride on cycle lanes, whether this is allowed or not. However, they self-regulate their positioning on the road depending on their actual speed. When they want to accelerate, speed e-bike users tend to leave bike lanes to ensure their own safety as well as that of other cyclists. These results allow a case to be made for a speed-based regulation according to which riders could use different segments of the public space alternatively depending on their actual speed at a given moment.

Background Platform-based fast delivery is developing rapidly in many cities across the world, especially in the food sector. Yet knowledge about the characteristics and the activity patterns of delivery couriers is scarce, especially in terms of their mobility behavior. Methodology Based on two questionnaire surveys conducted in 2020 and 2021 with 300 and 500 couriers respectively, this article analyses the profiles, motivations and mobility patterns of couriers working in Paris (France), with a focus on the impacts of the pandemic. Results First, the analysis of the profiles and motivations of couriers reveals that platform-based delivery is largely a temporary activity performed by young males of foreign origin, and undertaken as a student job or an entry to the labor market. Second, data on mobility patterns confirm that platform-based delivery is a dangerous activity with a high risk of road accidents. Moreover, many couriers break the law in order to increase their income by using motorized two-wheelers that are not legally permitted in France. We also show the use of shared bikes, which seems to be a great support tool for couriers who are starting work in this sector or have a problem with their own bikes. Third, the pandemic prompted many students to become platform-based delivery couriers in order to compensate for the lack of student jobs. It also worsened the working conditions of the majority of platform-based couriers. These findings raise new urban policy challenges and also new avenues for research in terms of topics and methods.

Shared dockless e-scooters were first launched in Paris in the summer of 2018. These services were met with mixed reception: although some praised them for offering a new mobility solution to urban dwellers, others soon questioned their environmental impact. An emerging body of literature using lifecycle analysis shows that shared e-scooters are more pollutant than walking, cycling, and public transportation, but remain preferable to cars. To better grasp the impacts of dockless e-scooters, it is therefore necessary to identify which modes of transportation they replace. As mobility highly depends on local context, city-specific data are needed. Although modal change data from cities in North America and New Zealand are available, there is no similar information from dense European cities. Using quantitative survey data collected from shared e-scooter users in Paris, the present research offers novel data on modal shift toward dockless e-scooters in the French capital. Results show that for their last trip riding a shared e-scooter, most users would have walked or used public transportation had e-scooters not been an option, and only a limited share of them would have used a car. However, the overall impact of e-scooters on walking and public transportation use remains limited and they display a significant complementarity with public transportation. Such city-specific data on e-scooter use and impacts provide valuable inputs for local public authorities to implement efficient and tailored regulatory measures, so as to include these services in sustainable mobility policies.

BACKGROUND The Pupillary Pain Index is a recent pupillometric index designed to assess the level of analgesia under general anesthesia in children and adults. If analgesia is inadequate, acute nociceptive stimuli such as skin incision may induce significant hemodynamic disturbances. AIMS Our aim was to investigate the potential relationship between pre-incision Pupillary Pain Index and heart rate increase following skin incision in children. METHODS This was a prospective, non-randomized, registered pilot study. We included children undergoing surgery under general anesthesia. Pupillary Pain Index was assessed 2 min before skin incision. Then, heart rate maximal variation (ΔHR ) and pupillary diameter maximal variation (ΔPD ) in the minute following incision were recorded. Spearman coefficient was calculated to characterize the relationship between Pupillary Pain Index and ΔHR or ΔPD . Using receiver operating characteristic curve analysis, we also studied the predictive value of pre-incision Pupillary Pain Index for heart rate and pupillary diameter reactivity. RESULTS 53 patients were included (10 ± 4 years, 40 ± 19 kg). There was a modest correlation between pre-incision Pupillary Pain Index and ΔHR (Spearman rs = 0.35 [0.05-0.57], p = .011), and between pre-incision Pupillary Pain Index and ΔPD (Spearman rs = 0.54 [0.33-0.71], p

The question of the impacts of ridesourcing on traffic externalities has emerged as a widely debated topic, and as a fundamental matter to address everywhere ridesourcing services developed. In order to understand these traffic-related outcomes, it is necessary to analyze the effects of ridesourcing on mobility practices. An emerging literature tackles the effects of modal shift linked to ridesourcing use on traffic volume (Vehicle Kilometers Travelled (VKT)). However, the role of ridesourcing in longer-run behavioral change, such as decisions relating to car ownership, has seldom been studied. The present article specifically focuses on Uber’s role in household car ownership reduction and resulting effects on traffic volume in the Paris Region, where ridesourcing has rarely been investigated. We put forward a novel methodology, using a survey of 1966 Uber users, to single out and measure the impacts of ridesourcing on car ownership. Through a Likert scale analysis, we show that Uber does not have an isolated effect on the decision to shed or sell a car without replacing it. The availability of Uber does, however, play a decisive role, along with other factors, in household car ownership reduction for a significant share of users. The use of prediction models eventually leads to a quantified estimation of the VKT that were saved by those cases of car ownership reduction linked to ridesourcing. The net difference between these avoided VKT and VKT Uber drivers generate while connected to the app reveals that the impact of the ridesourcing service on overall VKT in the Paris Region has been minimal thus far. But, as ridesourcing services continue to develop, their prospective ability to contribute to car ownership reduction and traffic-related effects remain unclear. The study’s overall findings bear instructive and potentially far-reaching policy implications, that may guide public authorities in their efforts to regulate ridesourcing services.

Background Pregnant women are at increased risk of hypoxaemia during general anaesthesia. Our aim was to determine the incidence and the risk factors that contribute to hypoxaemia in this setting. Methods Every woman 18 yr or older who underwent a non-elective Caesarean section under general anaesthesia was eligible to participate in this multicentre observational study. The primary endpoint was the incidence of hypoxaemia defined as the SpO2 ≤95%. The secondary endpoint was the incidence of difficult intubation defined as more than two attempts or failed intubation. Results During the study period, 895 women were prospectively included in 17 maternity hospitals, accounting for 79% of women who had general anaesthesia for non-elective Caesarean section. Maternal hypoxaemia was observed in 172 women (19%; confidence interval [CI], 17–22%). Risk factors associated with hypoxaemia in the multivariate analysis were difficult or failed intubation (adjusted odds ratio [aOR]=19.1 [8.6–42.7], P 35 kg m−2 (aOR=0.53 [0.28–0.998], P=0.0495). Intubation was difficult in 40 women (4.5%; CI, 3.3–6%) and failed intubation occurred in five women (0.56%; CI, 0.1–1%). In the multivariate analysis, use of a hypnotic drug other than propofol was associated with difficult or failed intubation (aOR=25 [2–391], P=0.02). A propensity score confirmed that propofol was associated with a significant decreased risk of difficulty or failure to intubate (P Conclusions Hypoxaemia during Caesarean sections was observed in 19% of women and was significantly associated with difficult or failed intubation. The use of propofol may protect against the occurrence of difficult intubation.

Objectives To provide recommendations to facilitate the management of severe thermal burns during the acute phase in adults and children. Design A committee of 20 experts was asked to produce recommendations in six fields of burn management, namely, (1) assessment, admission to specialised burns centres, and telemedicine; (2) haemodynamic management; (3) airway management and smoke inhalation; (4) anaesthesia and analgesia; (5) burn wound treatments; and (6) other treatments. At the start of the recommendation-formulation process, a formal conflict-of-interest policy was developed and enforced throughout the process. The entire process was conducted independently of any industry funding. The experts drew up a list of questions that were formulated according to the PICO model (Population, Intervention, Comparison, and Outcomes). Two bibliography experts per field analysed the literature published from January 2000 onwards using predefined keywords according to PRISMA recommendations. The quality of data from the selected literature was assessed using GRADE® methodology. Due to the current paucity of sufficiently powered studies regarding hard outcomes (i.e. mortality), the recommendations are based on expert opinion. Results The SFAR guidelines panel generated 24 statements regarding the management of acute burn injuries in adults and children. After two scoring rounds and one amendment, strong agreement was reached for all recommendations. Conclusion Substantial agreement was reached among a large cohort of experts regarding numerous strong recommendations to optimise the management of acute burn injuries in adults and children.

Rapid assessment of hemostasis during postpartum hemorrhage (PPH) is essential to allow characterization of coagulopathy, to estimate bleeding severity, and to improve outcome. Point of care (POC) coagulation monitors could be of great interest for early diagnosis and treatment of coagulation disorders in PPH.Women with ongoing PPH500 mL who clinically required an assessment of coagulation with thromboelastography (TEG) were included. The primary aim of this retrospective observational cohort study was to assess the predictive accuracy of TEG parameters for the diagnosis of coagulation disorders (hypofibrinogenemia ≤2 g/L, thrombocytopenia ≤80,000/mm, prothrombin ratio ≤50%, or activated partial thromboplastin time ratio ≥1.5) during PPH. The analyzed TEG parameters were Kaolin-maximum amplitude (K-MA), Kaolin-maximum rate of thrombus generation using G (K-MRTGG), functional fibrinogen-maximum amplitude (FF-MA), and functional fibrinogen-maximum rate of thrombus generation using G (FF-MRTGG). Secondary aims of this study were (1) comparison of the time delay between classical parameters and velocity curve-derived parameters (K-MA versus K-MRTGG and FF-MA versus FF-MRTGG) and (2) evaluation of the accuracy of TEG parameters to predict severe hemorrhage estimated by calculated blood losses.Ninety-eight patients were included with 98 simultaneous TEG analyses and laboratory assays. All parameters had an excellent predictive performance. For the Kaolin assay, no significant difference was evidenced between K-MA and K-MRTGG for the predictive performance for hypofibrinogenemia ≤2 g/L and/or thrombocytopenia ≤80,000/mm (respective area under the curve [AUC], 0.970 vs 0.981). For the functional fibrinogen assay, no significant difference was evidenced between FF-MA and FF-MRTGG for the predictive performance for hypofibrinogenemia ≤2 g/L (respective AUC, 0.988 vs 0.974). For both assays, the time to obtain results was shorter for the velocity parameters (K-MRTGG: 7.7 minutes [2.4 minutes] versus K-MA: 24.7 minutes [4.2 minutes], P.001; FF-MRTGG: 2.7 minutes [2.7 minutes] versus FF-MA: 14.0 minutes [4.3 minutes], P.001). All TEG parameters derived from the Kaolin and functional fibrinogen assays and Clauss fibrinogen were significantly predictive of severe PPH2500 mL.During PPH, when coagulation assessment is indicated, TEG provides a rapid and reliable detection of hypofibrinogenemia ≤2 g/L and/or thrombocytopenia ≤80,000/mm. No difference in performance was evidenced between the velocity-derived parameters (K-MRTGG and FF-MRTGG) and the classical parameters (K-MA and FF-MA). However, velocity-derived parameters offer the advantage of a shorter time to obtain results: FF-MRTGG parameter is available within ≤5 minutes. POC assessment of hemostasis during PPH management may help physicians to diagnose clotting disorders and to provide appropriate hemostatic support.

•Carsharing has yet to find a viable business model, leading to a highly unstable and competitive market.•The Paris Autolib’ case highlights that an increase in the number of users does not necessarily lead to profitability.•Authors discuss the following innovations: combined mobility, hybridation, lease-to-share, pricing innovations•Business model analysis demonstrates that technological innovation is not sufficient to create a lasting mobility service

The pupillary pain index (PPI) is a novel pupillometric index, designed to assess intraoperative analgesia. It is based on the evaluation of the pupillary response to electrical stimuli of increasing intensity. It ranges from 1 (low level of pupillary reactivity, high level of analgesia) to 10 (high level of pupillary reactivity, low level of analgesia). In this first evaluation of the PPI, our objective was to investigate the PPI changes after a bolus of 10 µg·kg(-1) of alfentanil in children under sevoflurane general anesthesia.After ethics committee approval and informed consent, 20 healthy children (9 ± 5 years) undergoing elective surgery under general anesthesia were included in this prospective, open, registered pilot study (NCT02646592). Anesthetic induction was standardized with sevoflurane 6% and propofol 1 mg·kg(-1). After tracheal intubation, sevoflurane concentration was maintained at 2% for 10 minutes. A first PPI measurement was performed (PPI-1), and a bolus of 10 µg·kg(-1) was administered. Two minutes after this bolus, a second PPI measurement was performed (PPI-2). Heart rate, blood pressure, and bispectral index were recorded before and after each PPI measurement. Resting pupillary diameter was recorded before each PPI measurement. PPI scores before and after the bolus of alfentanil were compared using a Wilcoxon signed rank test.PPI scores decreased after administration of a bolus of alfentanil (median difference: -3 [95% confidence interval, -4 to -2]). The median (quartiles) of PPI-1 (baseline, before alfentanil) was 6 (4, 7), and the median (quartiles) of PPI-2 (after alfentanil) was 2 (2, 3) (P.001). No difference was found in resting pupillary diameter before PPI-1 and PPI-2 (2.2 ± 0.2 and 2.2 ± 0.3 mm, respectively; P = .86). There were no significant changes in heart rate or blood pressure after PPI measurements (P = .46 and .49, respectively). Bispectral index was slightly increased after PPI measurements (P = .01; mean bispectral index increase5%). No withdrawal movements occurred during PPI measurements.There was a significant decrease in PPI after alfentanil administration. The results of this pilot study suggest that PPI score decreases when the level of analgesia increases. PPI measurement was not associated with a clinical or hemodynamic nociceptive response. This new index might provide useful information to individually adapt opioid administration before nociceptive stimuli under general anesthesia.

International audience; BACKGROUND : In this prospective study, we describe the electroencephalographic (EEG) profiles in children anesthetized with sevoflurane or propofol.METHODS : Seventy-three subjects (11 years, range 5-18) were included and randomly assigned to two groups according to the anesthetic agent. Anesthesia was performed by target-controlled infusion of propofol (group P) or by sevoflurane inhalation (group S). Steady-state periods were performed at a fixed randomized concentration between 2, 3, 4, 5, and 6 μg.ml-1 of propofol in group P and between 1, 2, 3, 4, and 5% of sevoflurane in group S. Remifentanil was continuously administered throughout the study. Clinical data, Bispectral Index (BIS), and raw EEG were continuously recorded. The relationship between BIS and anesthetic concentrations was studied using nonlinear regression. For all steady-state periods, EEG traces were reviewed to assess the presence of epileptoid signs, and spectral analysis of raw EEG was performed.RESULTS : Under propofol, BIS decreased monotonically and EEG slowed down as concentrations increased from 2 to 6 μg.ml-1 . Under sevoflurane, BIS decreased from 0% to 4% and paradoxically rose from 4% to 5% of expired concentration: this increase in BIS was associated with the occurrence of fast oscillations and epileptoid signs on the EEG trace. Propofol was associated with more delta waves and burst suppression periods compared to sevoflurane.CONCLUSION : Under deep anesthesia, the BIS and electroencephalographic profiles differ between propofol and sevoflurane. For high concentrations of sevoflurane, an elevated BIS value may be interpreted as a sign of epileptoid patterns or EEG fast oscillations rather than an insufficient depth of hypnosis.

The clinical benefits to be expected from intraoperative nociception monitors are currently under investigation. Among these devices, the Analgesia Nociception-Index (ANI) has shown promising results under sevoflurane anesthesia. Our study investigated ANI-guided remifentanil administration under propofol anesthesia. We hypothesized that ANI guidance would result in reduced remifentanil consumption compared with standard management. This prospective, randomized, controlled, single-blinded, bi-centric study included women undergoing elective gynecologic surgery under target-controlled infusion of propofol and remifentanil. Patients were randomly assigned to an ANI or Standard group. In the ANI group, remifentanil target concentration was adjusted by 0.5 ng mL−1 steps every 5 min according to the ANI value. In the Standard group, remifentanil was managed according to standard practice. Our primary objective was to compare remifentanil consumption between the groups. Our secondary objectives were to compare the quality of anesthesia, postoperative analgesia and the incidence of chronic pain. Eighty patients were included. Remifentanil consumption was lower in the ANI group: 4.4 (3.3; 5.7) vs. 5.8 (4.9; 7.1) µg kg−1 h−1 (difference = −1.4 (95% CI, −2.6 to −0.2), p = 0.0026). Propofol consumption was not different between the groups. Postoperative pain scores were low in both groups. There was no difference in morphine consumption 24 h after surgery. The proportion of patients reporting pain 3 months after surgery was 18.8% in the ANI group and 30.8% in the Standard group (difference = −12.0 (95% CI, −32.2 to 9.2)). ANI guidance resulted in lower remifentanil consumption compared with standard practice under propofol anesthesia. There was no difference in short- or long-term postoperative analgesia.

Micromechanical deformation phenomena such as those leading to macroscopic viscoelastic and plastic behavior must be studied from a thermodynamic viewpoint, as they induce complex and partly irreversible heat effects. Calorimetric measurements of the intrinsic volumetric thermomechanical heat sources (THS) activated in the material bulk during mechanical loads can produce valuable information with respect to that aim. They can be based on infrared imaging if submitted to inverse algorithms that allow a correct reconstruction of THS to be produced. Here, an inverse method relying on a diffusion-advection heat transfer model is applied to experimental temperature maps recorded during tensile tests. These are made on a semi-crystalline polymer that shows a strong development of plastic instabilities. Along with simultaneous kinematic observables produced with a digital image correlation system, the competition between advection and diffusion phenomena may be clearly established. 1-D profiles of the reconstructed THS and measured strain rates illustrate clearly that thermomechanical effects associated with necking onset and propagation follow the kinematic variable in a rather direct manner. Finally, we show for tensile experiments that THS estimations lead to analyze plasticity as a rheological behavior controlled by the flow stress, responsible of necking development and propagation.

Background Pupillometry has shown promising results for assessing nociception in anesthetized patients. However, its benefits in clinical practice are not demonstrated. The aim of this prospective randomized study was to evaluate the impact of intraoperative pupillometry monitoring on perioperative opioid consumption in major gynecologic surgery. Methods After receiving ethics committee approval and written consent of patients, American Society of Anesthesiologists status I to II women undergoing gynecologic surgery were included in this single-blinded, prospective, parallel-arm randomized study. General anesthesia was standardized with propofol–remifentanil target-controlled infusion. Patients were randomly assigned into two groups. In the pupillometry group, remifentanil administration was guided by pupillary diameter changes. In the standard group, remifentanil administration was left to the discretion of the anesthesiologist. The primary outcome was intraoperative remifentanil consumption. Results Fifty-five patients were analyzed. Remifentanil consumption was markedly decreased in the pupillometry group (3.8 [3.4 to 4.8 µg · kg–1 · h–1] vs. 7.9 µg · kg–1 · h–1 [6.5 to 9.0 µg · kg–1 · h–1] in the standard group; difference = 4.2 µg · kg–1 · h–1 [95% CI, 3.0 to 5.3 µg · kg–1 · h–1]; P < 0.001). Cumulative 0- to 12-h morphine consumption was reduced in the pupillometry group (two-way repeated measures ANOVA 0.3 ± 0.1 vs. 0.4 ± 0.2 mg/kg; P = 0.048). A telephone survey 3 months after surgery revealed that 15 of 29 patients in the standard group still experienced procedure-related pain versus 3 of 23 in the pupillometry group (chi-square P = 0.037). No adverse events associated with pupillometry were observed during the study. Conclusions The use of pupillometry to guide intraoperative analgesia reduced intraoperative remifentanil consumption and postoperative morphine requirements. The possible consequences of decreasing intraoperative remifentanil in terms of chronic pain require further investigation.

International audience; Alginate-based hydrogel scaffolds are widely used in the field of cartilage regeneration and repair. If the effect of autoclaving on the alginate powder is well known, it is not the same for the possible effects of the sterilization UV treatment on the properties of the hydrogel after polymerization. To select an effective sterilization treatment of alginate-based materials, one must find what are inter-relationship between the characteristics (chemical, physical and mechanical) of alginate-based hydrogel during sterilization, and what consequences have affected on cell behavior. In this study, we investigated the influence of UV sterilization treatments (UV-1 and UV-2: 25 and 50min, respectively) and autoclaving to obtain alginate (Alg)/hyaluronic acid (HA) hydrogel, as well as further evaluated the relationship between physicochemical properties and cell behavior of Alg/HA hydrogel after UVs and autoclaving. The physicochemical properties of this mixture at the powder or polymerized states were analyzed using ATR-FTIR, HPLC-SEC, rheological, indentation testing and sterility testing. The cell behaviors of hydrogels were evaluated by cell viability and proliferation, and chondrogenic differentiation. The effects of treatment parameters and their correlation with the others characteristics were determined statistically by Principal Component Analysis (PCA). In this study, we have shown that the cell behavior in alginate-based hydrogels was not only regulated by physicochemical properties (as molar mass or/and viscosity), but also associated with the controlling of sterilization time. It can provide a basis for choosing an effective method of sterilization, which can keep the mechanical or physical-chemical properties of Alg-based hydrogel scaffold and maintain its cytocompatibility and its ability to induce chondrogenesis from mesenchymal stem cells.

International audience; Once articular cartilage is damaged, it has poor ability to heal. At present, alginate-based hydrogels have 3D-dimensional physical structures with great potential for applications in carilage tissue engineering. For osteochondral defect, it will be necessary to use stratified scaffold to mimic zonal organization of cartilage. This study aims to compare the characteristics of alginate (Alg)/hyaluronic acid (HA) hydrogels which will mimic cartilage with alginate (Alg)/hydroxyapatite (Hap) hydrogels which will mimic subchondral bone. In this work, we fabricated the 3D-Alg/HA and Alg/Hap hydrogel scaffolds by the original spraying method. From the physical-mechanical properties, we compared mechanical behaviour of Alg/HA and Alg/Hap hydrogel scaffolds, which were examined using indentation testing and viscosity behaviour. This results showed that the Alg/Hap hydrogels exhibited a relative high mechanical strength, as well as the viscosity of Alg/Hap hydrogels is slight slower than Alg/HA hydrogels. However, autoclaving has more deleterious effect on the mechanical and viscosity properties of Alg/HA and Alg/Hap hydrogels. Cytotoxicity was evaluated through the culture of hydrogel beads-laden Wharton's jelly mesenchymal stem cells (WJ-MSC). In addition, the chondrogenic differentiation of WJ-MSC encapsulated into Alg/HA and Alg/Hap hydrogels were performed by histological analyzing during 30 days of culture. From these results, the percentage of living cells for Alg/Hap is significantly higher than Alg/HA, which also is associated with the results of shear viscosity. Both of hydrogels exhibited differentiate into chondrocyte matrix as collagen and proteoglycans. In conclusion, Alg/Hap hydrogels presented better mechanical property, cytocompatibility and differentiation characteristics than Alg/HA hydrogels.

BACKGROUND Pupillometry monitoring under general anesthesia is based on the assumption that pupillary diameter variations reflect the adequacy of the provided analgesia to the intensity of the nociceptive surgical stimulus. The accurate interpretation of pupillometric data requires establishing clearly what the expected baseline unstimulated pupillary diameter at each specific level of hypnosis is. Opioids decrease pupillary diameter in a dose-dependent fashion. In contrast, the effects of hypnotic drugs on pupillary diameter are not well known. Our aim was to describe the potential relationship between propofol predicted effect-site concentrations (Cets) ranging from 1 to 3 µg/mL and pupillary diameter. METHODS Patients were randomized to receive propofol by target-controlled infusion at a predicted Cet of 1, 2, or 3 µg/mL (groups P1, P2, and P3, respectively). Pupillary diameter measurements were performed after 10 minutes of steady-state propofol infusion at the randomized Cet. No stimulation was performed during the study. Heart rate and bispectral index (BIS) were continuously recorded. RESULTS Forty patients were included: (13, 14, and 13 in groups P1, P2, and P3, respectively). Mean pupillary diameter was 5.7 mm (1 mm) in group P1, 4.8 mm (1.3 mm) in group P2, and 3.3 mm (0.8 mm) in group P3. Propofol had a dose-dependent effect on pupillary diameter (linear regression R = 0.45, P < .001). Pupillary diameter was positively correlated with the BIS (Spearman r = 0.75 [95% confidence interval (CI), 0.54 to -0.87] P < .001). CONCLUSIONS From 1 to 3 µg/mL of predicted Cet, propofol has a dose-dependent effect on pupillary diameter. Within this concentrations range, there is a positive correlation between BIS and pupillary diameter. The subcortical effect of propofol on pupillary diameter is correlated to its effect on the cortex. Studies assessing pupillary diameter as a marker of the nociception-antinociception balance should be performed in patients with a standardized depth of hypnosis.

Les troubles complexes du langage apparaissent comme des symptomes handicapants qui necessitent une prise en charge pluridisciplinaire dans un lieu de soins tiers en lien avec les differents espaces de vie des jeunes.La presentation du dispositif mis en place par le sessad Bossuet illustre la pertinence d’un accompagnement global pour ces jeunes « dysphasiques ». La rythmicite des soins autour d’un espace integratif leur permet de tisser leur vecu et d’elaborer leur pensee.L’exemple clinique de Tom met en lumiere l’efficience de ce service de soins dans lequel la continuite, la contenance, le respect de l’evolution et de la prise de parole sont des fondamentaux.

Pupillometry has shown promising results for assessing nociception in anesthetized patients. However, its benefits in clinical practice are not demonstrated. The aim of this prospective randomized study was to evaluate the impact of intraoperative pupillometry monitoring on perioperative opioid consumption in major gynecologic surgery.After receiving ethics committee approval and written consent of patients, American Society of Anesthesiologists status I to II women undergoing gynecologic surgery were included in this single-blinded, prospective, parallel-arm randomized study. General anesthesia was standardized with propofol-remifentanil target-controlled infusion. Patients were randomly assigned into two groups. In the pupillometry group, remifentanil administration was guided by pupillary diameter changes. In the standard group, remifentanil administration was left to the discretion of the anesthesiologist. The primary outcome was intraoperative remifentanil consumption.Fifty-five patients were analyzed. Remifentanil consumption was markedly decreased in the pupillometry group (3.8 [3.4 to 4.8 µg · kg · h] vs. 7.9 µg · kg · h [6.5 to 9.0 µg · kg · h] in the standard group; difference = 4.2 µg · kg · h [95% CI, 3.0 to 5.3 µg · kg · h]; P0.001). Cumulative 0- to 12-h morphine consumption was reduced in the pupillometry group (two-way repeated measures ANOVA 0.3 ± 0.1 vs. 0.4 ± 0.2 mg/kg; P = 0.048). A telephone survey 3 months after surgery revealed that 15 of 29 patients in the standard group still experienced procedure-related pain versus 3 of 23 in the pupillometry group (chi-square P = 0.037). No adverse events associated with pupillometry were observed during the study.The use of pupillometry to guide intraoperative analgesia reduced intraoperative remifentanil consumption and postoperative morphine requirements. The possible consequences of decreasing intraoperative remifentanil in terms of chronic pain require further investigation.

BACKGROUND Pupillometry allows the measurement of pupillary diameter variations in response to nociceptive stimuli. This technique has been used to monitor the balance between analgesia and nociception. Under general anesthesia, the amplitude of pupillary dilation is related to the amount of administered opioids. The objective of this study was to determine whether at a constant infusion rate of opioids, the pupillary response was influenced by depth of hypnosis assessed by the bispectral index (BIS). METHODS Twelve patients (14-20 years) anesthetized for orthopedic surgery were included. Under propofol-remifentanil target-controlled infusion, remifentanil effect site target concentration was fixed at 1 ng/mL. Two measures of pupillary reflex dilation were performed on each patient in a randomized order: one at BIS 55 and one at BIS 25. These levels of BIS were obtained by adjusting propofol target concentration and maintained for 10 minutes before each measure. For each measure, we applied a standardized tetanic stimulation on the patient's forearm (60 mA, 100 Hz, 5 seconds). All measures were performed before the beginning of surgery. RESULTS Pupillary dilation was significantly greater at BIS 55 than at BIS 25: 32.1% ± 5.3% vs 10.4% ± 2.5% (mean difference estimate [95% confidence interval]: 21.8% [12.9-30.6], P < .001), without carryover effect (P = .30) nor period effect (P = .52). Hemodynamic parameters and BIS were not modified by the stimulation. CONCLUSIONS In patients receiving a constant infusion of remifentanil at a target concentration of 1 ng/mL, pupillary dilation after a standardized tetanic stimulation was influenced by depth of hypnosis assessed by the BIS.

The risk of difficult upper airway access is increased during pregnancy, especially in labor. Changes in upper airway calibre have been poorly studied during pregnancy. The acoustic reflection method is a non-invasive technique that allows a longitudinal assessment of the cross-sectional area of the upper airway from the mouth to carina. We used this technique to evaluate upper airway calibre during normal pregnancy.We conducted a prospective, single centre, observational study with a clinical and upper airway acoustic reflection method evaluation of healthy women during the first, second and third trimesters of pregnancy, and up to two days and one month after delivery.Fifty women participated to the study. The mean pharyngeal cross-sectional area decreased between the first and third trimesters (P0.001) with no significant change of the minimal and mean tracheal cross-sectional areas. The Mallampati score increased during pregnancy between the first and third trimesters (P0.001).Using measurements with the acoustic reflection method, normal pregnancy is associated with a significant reduction in the cross-sectional area of the pharynx and a concomitant increase in the Mallampati score. No change was observed in the minimal and mean tracheal cross-sectional areas.

Les differentes formules de l’autopartage suscitent un interet legitime, mais il est plus rare d’etudier les mutations des pratiques de mobilite engendrees par cette nouvelle facon d’utiliser la voiture. C’est ce que propose l’article consacre a l’autopartage, issu d’une enquete aupres de 2000 adherents dans le cadre d’une recherche financee par le PREDIT. Il en ressort que la pratique de l’autopartage entraine une reduction de l’usage de la voiture, voire une baisse de la propriete d’un vehicule, et une baisse du nombre de kilometres parcourus en voiture, grâce a la rationalisation des deplacements. L’autopartage offre egalement aux personnes n’ayant pas de voiture la possibilite d’effectuer des deplacements occasionnels par ce mode.

Gestational diabetes insipidus is an uncommon clinical disease whose prevalence is approximately two to three pregnancies per 100,000. It may be isolated or associated with preeclampsia. We report a case of gestational diabetes insipidus in a twin pregnancy, originally isolated during two months, and secondarily complicated by HELLP-syndrome. We recall the specific pathophysiology of polyuric-polydipsic syndrome during pregnancy and summarize its various causes. Finally, we discuss the indications, in case of isolated gestational diabetes insipidus, of treatment by dDAVP.

For several years, total intravenous anaesthesia (TIVA) has demonstrated many advantages that allow considering propofol anaesthesia as an interesting alternative in pediatric anaesthesia. TCI in children requires calculation and validation of pharmacokinetic (PK) models specifically adapted to the paediatric population. Several PK models based on a 3-compartement approach have been proposed in children: all these models, which integrate only weight as covariable, show increased distribution volumes with a wide interindividual variability. The particular importance to include physiological covariables, as age and lean body mass, to describe metabolic processes during growth and maturation in pediatric PKPD models is in agreement with recent allometric scaling works in children. However, as pharmacodynamic (PD) parameters are still debated in children, there is up to now, no PKPD model currently available for paediatric anaesthesia. Schnider et al.'s model, a model described in adults that includes numerous covariables, may be adapted and more efficient than the classical paediatric models to describe propofol-PKPD relationship in children over 5years. Whatever the model, a pharmacodynamic feedback such as the bispectral index may be useful to counteract interindividual variability in the paediatric population.

Background Sevoflurane has become the gold standard for inhalation induction in children. However in children as in adults, epileptiform electroencephalographic signs have been described under high concentrations of sevoflurane. The aim of this study was to determine the minimal alveolar concentration (MAC) of sevoflurane associated with the occurrence of major epileptiform signs (MES) in 50% children under steady-state conditions. The MAC of MES (MAC MES) was determined in 100% oxygen and with the addition of 50% nitrous oxide or after the injection of alfentanil (ALFENTA). Methods Seventy-nine children (3-11 yr), undergoing elective surgery and premedicated with hydroxyzine were included. After induction by inhalation and tracheal intubation, a 10-min period with a stable expired fraction of sevoflurane was obtained. The MES were defined as rhythmic polyspikes or epileptiform discharges. Electroencephalographic recordings were blindly analyzed by two independent experts. The MAC MES were determined by the Dixon method: the concentration of sevoflurane was determined by the result from the previous patient: increase of 0.2% if MES were absent or decrease of 0.2% if MES were present. Three consecutive series were performed: (1) in 100% oxygen (MAC MESO2); (2) in 50% oxygen and 50% nitrous oxide (MAC MESN2O); and (3) in 100% oxygen with a bolus of alfentanil (MAC MESALFENTA). Results The MAC MESO2 was 4.3±0.1% (mean±SD), the MAC MESN2O and the MAC MESALFENTA were higher, respectively: 4.6±0.2% (P=0.01) and 4.6±0.2% (P=0.02). Conclusions In children premedicated with hydroxyzine, the MAC MES of sevoflurane calculated in 100% O2 corresponded to 1.75 surgical MAC. In addition, our results have demonstrated a moderate effect of nitrous oxide and alfentanil in raising the threshold of MES.

SummaryBackground In children, only a few studies have compared different modes of propofol infusion during a total intravenous anesthesia (TIVA) with propofol and remifentanil. The aim of this study was to compare Bispectral Index (BIS) profiles (percentage of time spent at adequate BIS values) between four modes of propofol infusion: titration of the infusion rate on clinical signs (TIVA0), titration of the infusion rate on the BIS (TIVABIS), target controlled infusion (TCI) guided by the BIS either with the Kataria model (TCI KBIS) or the Schnider model (TCI SBIS). Methods Sixty-six children (aged from 4 to 14 years) were prospectively randomized into one of the four groups. In the TIVA0 group, the anesthesiologist was blinded to the BIS. In each group, the percentage of time with adequate BIS values (45–55), the bias, and imprecision were calculated. Results The propofol consumption was similar in the four groups. During the maintenance phase, the percentage of time spent in the targeted BIS range was significantly lower in the TIVA0 group compared to the three other groups (TIVA0: 31% ± 22, TIVABIS: 59% ± 17, TCI KBIS: 53% ± 12, TCI SBIS: 56% ± 17). The bias was not statistically different between the four groups, but the imprecision was larger for the TIVA0 group. Compared to the Kataria model, the Schnider model was associated with shorter time delay to reach the desired BIS, to eyes opening, and to tracheal extubation. Conclusions Propofol administration using manual infusion guided by clinical signs was associated with higher risks of over- or underdosage when compared to BIS-guided administrations. When propofol infusion was guided by the BIS, no major difference was found between TIVA and TCI (either with the Kataria or the Schnider model). This study highlights the need of a pharmacodynamic feedback during propofol anesthesia in children.

Summary Background Analgesia and nociception can not be specifically monitored during general anesthesia. Movement of the patient or hemodynamic variations are usually considered as symptoms of insufficient analgesia. The measure of skin conductance (SC) allows an assessment of peripheral sympathetic activity. The analgesia-nociception index (ANI) provides an evaluation of the parasympathetic activity based on heart rate variability. These two non-invasive monitors might allow a better assessment of perioperative nociception. Objectives Describe the profiles of SC and ANI after a standardized nociceptive stimulation, in anesthetized children, at different infusion rates of remifentanil. Materials/Methods For this pilot study, 12 children (8.4 ± 5 years) scheduled for middle-ear surgery were anesthetized with desflurane to maintain a bispectral index at 50. Remifentanil was used for analgesia, at an initial infusion rate of 0.2 μg·kg−1·min−1. Remifentanil infusion rate was then decreased: Five steady-state periods of 10 min were obtained at 0.2, 0.16, 0.12, 0.08, and 0.04 μg·kg−1·min−1. At the end of each period, a standardized tetanic stimulation was applied to the patient. Variations in heart rate, blood pressure, SC, and ANI were recorded before and after each stimulation. Results After the stimulation, ANI was significantly decreased compared with prestimulation values for all remifentanil infusion rates. This decrease was greater at 0.04 μg·kg−1·min−1 than at the other infusion rates. SC, heart rate, and blood pressure were not modified by the stimulations, whatever the dose of remifentanil. Conclusion ANI might provide a more sensitive assessment of nociception in anesthetized children than hemodynamic parameters or skin conductance.

In children, sevoflurane is the most commonly used anaesthetic. Its excellent haemodynamic tolerance gives it a wide therapeutic index. This halogenated agent can abolish movement [minimal alveolar concentration (MAC)] or haemodynamic responses (MACBAR) to noxious stimulus in children as in adults. Reflex pupillary dilatation (RPD) has been demonstrated as a very sensitive measure of noxious stimulation. In order to investigate the effect of sevoflurane on the RPD, a subcortical reflex, we determined the MAC of sevoflurane inhibiting the RPD in 50% of the subjects in response to skin incision (MACpup) in pre- and post-pubertal subjects.We included 30 pre-pubertal children and 19 post-pubertal subjects. Patients received sevoflurane at preselected concentrations according to an 'up and down' design, and after a steady-state period, skin incision was performed. The RPD was considered as significant when the pupillary diameter increased by more than 100%. Heart rate (HR) and bispectral index (BIS) changes were analysed according to the pupillary response.The MACpup of sevoflurane was 4.8% (95% confidence interval, 4.6-5.1%) in pre-pubertal children vs 3.4% (3.5-3.3%) in post-pubertal subjects (P0.001). Inhibition of RPD was always associated with lack of significant HR response. In pre-pubertal children receiving high concentrations of sevoflurane, RPD in response to noxious stimulation was frequently associated with lack of HR response and low BIS values.MACpup was higher than MAC and close to the MACBAR. Inhibition of RPD in pre-pubertal children required higher sevoflurane concentrations compared with post-pubertal subjects, suggesting that the relationship between the brain structure sensitivities may differ with brain maturation.

International audience; We survey a class of algorithms to evaluate polynomials with floating point coefficients and for computation performed with IEEE-754 floating point arithmetic. The principle is to apply, once or recursively, an error-free transformation of the polynomial evaluation with the Horner algorithm and to accurately sum the final decomposition. These compensated algorithms are as accurate as the Horner algorithm performed in K times the working precision, for K an arbitrary integer. We prove this accuracy property with an \apriori error analysis. We also provide validated dynamic bounds and apply these results to compute a faithfully rounded evaluation. These compensated algorithms are fast. We illustrate their practical efficiency with numerical experiments on significant environments. Comparing to existing alternatives these K-times compensated algorithms are competitive for K up to 4, i.e., up to 212 mantissa bits.

International audience; We perform forced-drainage experiments in aqueous foams and compare the results with data available in the literature. We show that all the data can be accurately compared together if the dimensionless permeability of the foam is plotted as a function of liquid fraction. Using this set of coordinates highlights the fact that a large part of the published experimental results corresponds to relatively wet foams (E ∼ 0.1). Yet, most of the foam drainage models are based on geometrical considerations only valid for dry foams. We therefore discuss the range of validity of the different models in the literature and their comparison to experimental data. We propose extensions of these models considering the geometry of foam in the relatively wet-foam limit. We eventually show that if the foam geometry is correctly described, forced drainage experiments can be understood using a unique parameter —the Boussinesq number.

In this prospective study, we compared the relationship between propofol concentrations and bispectral index (BIS) in children versus young adults anesthetized with target-controlled infusion (TCI) of propofol.Forty-five prepubertal subjects (children) and 45 postpubertal subjects (adults) were studied. All patients were anesthetized with TCI of propofol, based on the Kataria et al.'s model for children and on the Schnider et al.'s model for adults. All data from the BIS and the TCI system were continuously recorded using Rugloop software. Remifentanil was continuously administered throughout the study (0.25 microg x kg(-1) x min(-1)). In all patients, after the end of surgery, a 12-min period with a stable target plasma concentration (Ct) of propofol, randomly assigned at 2, 3, 4, 5, and 6 microg/mL, was performed. In addition, in most of the patients, another 12-min period was performed during which the BIS was targeted at 50 +/- 5. After each 12-min steady-state period, the Ct and BIS were noted and the plasma concentration of propofol was measured (Cm). The Ct and Cm corresponding to half maximal effect (BIS(50)) was determined by the Hill equation, and by targeting BIS at 50.In children, as in adults, BIS values were highly correlated with the corresponding Ct or Cm of propofol following classical E(max) dose-response curves. The ECt(50) and the ECm(50), derived from the dose-response curves, were higher in children than in adults: ECm(50): 4.0 (3.6-4.5) microg/mL vs 3.3 (3.0-3.7) microg/mL [mean (95% CI)], P0.001; as well were the Ct and Cm clinically obtained when BIS was targeted at 50 (Cm(50): 4.3 +/- 1.1 microg/mL vs 3.4 +/- 1.2 microg/mL, (mean +/- SD) P0.05, children versus adults). Cm was generally under-estimated by the Ct, and the bias was higher in children than in adults: 2.6 +/- 2.6 microg/mL vs 1.7 +/- 1.6 microg/mL (P = 0.05).The good relationship between propofol and BIS demonstrated in children as in adults suggested a slightly lower sensitivity to propofol in children. As the predictability of plasma propofol concentrations with the classical pharmacokinetic/pharmacodynamic models is limited in children, a cerebral pharmacodynamic feedback, such as BIS, may be useful in this population.

We investigate the compaction dynamics of vibrated granular suspensions using both digital imaging technique and MRI measurements. Starting from initialy loose packings, our experimental data suggest the existence of two stages in the compaction dynamics: a fast stage at short times where a rising compaction front propagates through the granular suspension and a slow stage at large times where the packing compacts slowly and homogeneously. The compaction dynamics in each stage can be well fitted to usual stretched exponential laws with stretching exponents equal to 2 and 0.45, respectively. The transition time between these two stages, τ c , depends on the fluid viscosity, vibration intensity and grain diameter. We show that τ −1 and the velocity of the front decrease roughly linearly with the lubrication Peclet number, Pe lub related to the competition between the lubrication stress induced by vibrations and the granular pressure.

The aim of this chapter is to provide the pediatric anesthesiologist with the main principles and current strategies for neonatal anesthesia. Part one presents the general principles including the aims of anesthesia and the strategies to attain them, the potential for anesthetic toxicity, and, lastly, the notion of optimal risk-benefit ratio. Part two details anesthetic techniques and recent advances in neuroaxial anesthesia, rapid sequence induction technique, and anesthesia for elective surgery.

This short review is aimed at describing the particularities of consent in paediatric patients. For routine procedures, the consent of one of the parents is required whereas both parents should sign the consent for research protocols. In case of difficulties such as Jehovah witnesses or parental opposite opinions, doctors should ask the question to the judge in charge of protection of children. Consent or at least assent of minors enrolled in research protocols should be obtained provided their maturity is sufficient to understand correctly the purpose of clinical research.

Let Γ be an irreducible cocompact lattice in a product G 1 × G 2 of locally compact groups. We show that, under natural assumptions, an irreducible representation of F with non-trivial 1-cohomology extends to a representation of the ambiant group or weakly contains 1p.

This paper deals with the accuracy of complex division in radix-two floating-point arithmetic. Assuming that a fused multiply-add (FMA) instruction is available and that no underflow/overflow occurs, we study how to ensure high relative accuracy in the component wise sense. Since this essentially reduces to evaluating accurately three expressions of the form ac+bd, an obvious approach would be to perform three calls to Kahan's compensated algorithm for 2 by 2 determinants. However, in the context of complex division, two of those expressions are such that ac and bd have the same sign, suggesting that cheaper schemes should be used here (since cancellation cannot occur). We first give a detailed accuracy analysis of such schemes for the sum of two nonnegative products, providing not only sharp bounds on both their absolute and relative errors, but also sufficient conditions for the output of one of them to coincide with the output of Kahan's algorithm. By combining Kahan's algorithm with this particular scheme, we then deduce two new division algorithms. Our first algorithm is a straight-line program whose component wise relative error is always at most 5u+13u2 with u the unit round off, we also provide examples of inputs for which the error of this algorithm approaches 5u, thus showing that our upper bound is essentially the best possible. When tests are allowed we show with a second algorithm that the bound above can be further reduced to 4.5u+9u2, and that this improved bound is reasonably sharp.

We consider in this paper a relative version of the Howe-Moore Property, about vanishing at infinity of coefficients of unitary representations. We characterize this property in terms of ergodic measure-preserving actions. We also characterize, for linear Lie groups or p-adic Lie groups, the pairs with the relative Howe-Moore Property with respect to a closed, normal subgroup. This involves, in one direction, structural results on locally compact groups all of whose proper closed characteristic subgroups are compact, and, in the other direction, some results about the vanishing at infinity of oscillatory integrals., Comment: 25 pages, no figure

The compensated Horner algorithm improves the accuracy of polynomial evaluation in IEEE-754 floating point arithmetic: the computed result is as accurate as if it was computed with the classic Horner algorithm in twice the working precision. Since the condition number still governs the accuracy of this computation, it may return an arbitrary number of inexact digits. We address here how to compute a faithfully rounded result, that is one of the two floating point neighbors of the exact evaluation. We propose an a priori sufficient condition on the condition number to ensure that the compensated evaluation is faithfully rounded. We also propose a validated and dynamic method to test at the running time if the compensated result is actually faithfully rounded. Numerical experiments illustrate the behavior of these two conditions and that the associated running time over-cost is really interesting.

Several different techniques and softwares intend to improve the accuracy of results computed in a fixed finite precision. Here we focus on a method to improve the accuracy of the polynomial evaluation. It is well known that the use of the Fused Multiply and Add operation available on some microprocessors like Intel Itanium improves slightly the accuracy of the Horner scheme. In this paper, we propose an accurate compensated Horner scheme specially designed to take advantage of the Fused Multiply and Add. We prove that the computed result is as accurate as if computed in twice the working precision. The algorithm we present is fast since it only requires well optimizable floating point operations, performed in the same working precision as the given data.

Compensated algorithms improve the accuracy of a re- sult evaluating a correcting term that compensates the finite precision of the computation. The implementation core of compensated algorithms is the computation of the rounding errors generated by the floating point operators. We focus this operator dependency discussing how to manage and to benefit from floating point arithmetic implemented through a fused multiply and add operator. We consider the com- pensation of dot product and polynomial evaluation with Horner iteration. In each case we provide theoretical a pri- ori error bounds and numerical experiments to exhibit the best algorithmic choices with respect to accuracy or perfor- mance issues.

Introduction Dans une maternite de type 3 de plus de 3000 naissances, la presence d’un IADE poste en salle de naissance (SDN) joue un role important dans la surveillance et l’optimisation de l’analgesie peridurale (APD) obstetricale. Les reinjections peridurales par l’IADE, apres evaluation clinique, doivent etre faites sous couvert de prescription medicale [1] . Le but de cette etude est l’evaluation d’un protocole de prise en charge par les IADE d’une APD obstetricale non optimale, sous forme d’un arbre decisionnel ( Fig. 1 ). Materiel et methodes Enquete prospective observationnelle menee d’avril 2013 a mars 2014 sous forme d’EPP. Apres chaque intervention par l’IADE en SDN pour APD non optimale, sur la base du protocole, une fiche descriptive sous forme de questionnaire a ete remplie par l’IADE. L’objectif principal du questionnaire etait d’evaluer le pourcentage d’analgesie optimisee apres intervention de l’IADE. Les objectifs secondaires etaient l’analyse des echecs d’analgesie (niveau symetrique insuffisant (NSI), defaut de puissance (DP), niveau asymetrique (NA)), l’evaluation du suivi conforme au protocole, les situations eventuelles non prevues par ce dernier et le taux d’interventions secondaires sous anesthesie generale (AG). Resultats Sur une periode de 11 mois, 85 questionnaires ont ete remplis a la suite d’appels pour APD non satisfaisante. Dans 84 % des cas la premiere intervention par l’IADE sur la base du protocole a ete efficace et suffisante, tandis que dans 16 % des cas une seconde intervention a ete necessaire apres appel du MAR. Les causes retrouvees d’APD inefficace etaient par ordre de frequence decroissante un DP (76 %), un NSI (13 %), un NA (11 %). L’intervention etait en adequation avec le protocole dans 81 % des cas et l’administration inadaptee de clonidine etait l’erreur de suivi du protocole la plus frequente dans les autres cas. Le protocole etait applicable a toutes les situations rencontrees. Une seconde pose d’APD a ete realisee avec succes chez trois patientes. Une cesarienne a ete necessaire en cours de travail pour 13 patientes (15 %) dont 12 sous APD et 1 sous AG. Discussion La surveillance reguliere et l’optimisation de l’APD obstetricale permet de limiter les echecs et d’eviter le recours a l’AG dans certains cas [2] . La mise a disposition d’un protocole d’evaluation et de reinjection en cas d’APD inefficace permet a l’IADE de jouer un role important dans le depistage et la prise en charge de la plupart des APD inefficaces permettant une meilleure optimisation de l’APD et limitant ainsi le recours a l’AG en cas d’echec.

In most of the western countries, car is the prevalent means of transport for local mobility. At the same time, sensitivity to environmental issues is increasing, correlated to the consciousness that carbon dioxide emissions have to be reduced. In regard to these two trends (individual mobility and public opinions favourable to a reduction of carbon emissions), energy-efficient vehicles will probably develop in the future—car manufacturers actually prepare new offers for the mass market. Comparable cases have occurred during the last decades—probably more modest but full of learning: some local authorities have promoted innovations based on electric vehicles in the 1990s, and some people have chosen this kind of cars for their daily travels. This article deals with these pioneers (This article comes from a communication at the ECEEE Summer Study, June 2009, Panel 6: Energy efficiency in transport and mobility.). Reporting studies carried out in 2006 and 2008, we intend to identify the reasons of this innovative modal choice, to show the difficulties that electric vehicle drivers then encountered and to analyse the patterns of use that governed their mobility and their use of electric vehicles.