Preoperative ketamine administration for prevention of postoperative neurocognitive disorders after major orthopedic surgery in elderly patients: A multicenter randomized blinded placebo-controlled trial.

BACKGROUND: Preventive anesthetic impact on the high rates of postoperative neurocognitive disorders in elderly patients is debated. The Prevention of postOperative Cognitive dysfunction by Ketamine (POCK) study aimed to assess the effect of ketamine on this condition. METHODS: This is a multicenter, randomized, double-blind, interventional study. Patients ≥60 years undergoing major orthopedic surgery were randomly assigned in a 1:1 ratio to receive preoperative ketamine 0.5 mg/kg as an intravenous bolus (n = 152) or placebo (n = 149) in random blocks stratified according to the study site, preoperative cognitive status and age. The primary outcome was the proportion of objective delayed neurocognitive recovery (dNR) defined as a decline of one or more neuropsychological assessment standard deviations on postoperative day 7. Secondary outcomes included a three-month incidence of objective postoperative neurocognitive disorder (POND), as well as delirium, anxiety, and symptoms of depression seven days and three months after surgery. RESULTS: Among 301 patients included, 292 (97%) completed the trial. Objective dNR occurred in 50 (38.8%) patients in the ketamine group and 54 (40.9%) patients in the placebo group (OR [95% CI] 0.92 [0.56; 1.51], p = 0.73) on postoperative day 7. Incidence of objective POND three months after surgery did not differ significantly between the two groups nor did incidence of delirium, anxiety, apathy, and fatigue. Symptoms of depression were less frequent in the ketamine group three months after surgery (OR [95% CI] 0.34 [0.13-0.86]). CONCLUSIONS: A single preoperative bolus of intravenous ketamine does not prevent the occurrence of dNR or POND in elderly patients scheduled for major orthopedic surgery. (Clinicaltrials.gov NCT02892916).

La Société de Biologie de Strasbourg : 100 ans au service de la science et de la société.

Founded in 1919, the Society of Biology of Strasbourg (SBS) is a learned society whose purpose is the dissemination and promotion of scientific knowledge in biology. Subsidiary of the Society of Biology, the SBS celebrated its Centenary on Wednesday, the 16th of October 2019 on the Strasbourg University campus and at the Strasbourg City Hall. This day allowed retracing the various milestones of the SBS, through its main strengths, its difficulties and its permanent goal to meet scientific and societal challenges. The common thread of this day was the transmission of knowledge related to the past, the present, but also the future. At the start of the 21st century, the SBS must continue to reinvent itself to pursue its objective of transmitting scientific knowledge in biology and beyond. Scientific talks performed by senior scientists and former SBS thesis prizes awardees, a round table, and informal discussions reflected the history and the dynamism of the SBS association. All SBS Centennial participants have set the first milestone for the SBS Bicentennial.

TITLE: La Société de Biologie de Strasbourg : 100 ans au service de la science et de la société. ABSTRACT: Filiale de la Société de Biologie, la Société de Biologie de Strasbourg (SBS) est une société savante qui a pour objet la diffusion et la promotion du savoir scientifique en biologie et en médecine. Fondée en 1919, La SBS a célébré son Centenaire le mercredi 16 octobre 2019. Cette journée a permis de retracer les différents jalons de la SBS, à travers ses lignes de forces, ses difficultés et sa volonté permanente de mettre en exergue les défis scientifiques et sociétaux auxquels participent les recherches strasbourgeoises. Le fil rouge de cette journée a été la transmission d'un savoir en lien avec le passé, le présent, mais également le futur. En ce début du 21e siècle, la SBS se doit de continuer de se réinventer pour poursuivre son objectif de transmission des connaissances scientifiques en biologie et au-delà. L'ensemble des participants du Centenaire de la SBS a ainsi posé la première pierre du Bicentenaire de la SBS.

Veno-arterial-ECMO in the intensive care unit: From technical aspects to clinical practice.

The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) as a salvage therapy in cardiogenic shock is becoming of current practice. While VA-ECMO is potentially a life-saving technique, results are sometimes mitigated, emphasising the need for selecting the right indication in the right patient. This relies upon a clear definition of the individual therapeutic project, including the potential for recovery as well as the possible complications associated with VA-ECMO. To maximise the benefits of VA-ECMO, the basics of extracorporeal circulation should be perfectly understood since VA-ECMO can sometimes be detrimental. Hence, to be successful, VA-ECMO should be used by teams with sufficient experience and initiated after a thorough multidisciplinary discussion considering patient's medical history, pathology as well the anticipated evolution of the disease.

[History of the Strasbourg Society of Biology]. / Histoire de la Société de Biologie de Strasbourg.

The Society of Biology of Strasbourg (SBS) is a learned society that was created in 1919 based on the model of the Society of Biology of which it is a subsidiary. Like its Parisian colleague, SBS aims at diffusing and promoting scientific knowledge in biology. To achieve this goal, SBS initiated since its creation a dialogue interface between researchers in biology and physicians, and more recently with other scientific disciplines, industry and the civil society. At the dawn of its first century, the Society of Biology of Strasbourg must continue to reinvent itself to pursue its development and to fulfil its mission of sharing scientific knowledge. This work continues in strong collaboration with our partners that share with SBS the willingness to foster excellence in biological research in Strasbourg, its region and beyond.

Early impairment of intracranial conduction time predicts mortality in deeply sedated critically ill patients: a prospective observational pilot study.

BACKGROUND: Somatosensory (SSEP) and brainstem auditory (BAEP) evoked potentials are neurophysiological tools which, respectively, explore the intracranial conduction time (ICCT) and the intrapontine conduction time (IPCT). The prognostic values of prolonged cerebral conduction times in deeply sedated patients have never been assessed. Sedated patients are at risk of developing new neurological complications, undetected. In this prospective observational bi-center pilot study, we investigated whether early impairment of SSEP's ICCT and/or BAEP's IPCT could predict in-ICU mortality or altered mental status (AMS), in deeply sedated critically ill patients. METHODS: SSEP by stimulation of the median nerve and BAEP were assessed in critically ill patients receiving deep sedation on day 3 following ICU admission. Deep sedation was defined by a Richmond Assessment sedation Scale (RASS) <-3. Mean left- and right-side ICCT and IPCT were measured for each patient. Primary and secondary outcomes were, respectively, in-ICU mortality and AMS defined as the occurrence of delirium and/or delayed awakening after discontinuation of sedation. RESULTS: Eighty-six patients were studied of which 49 (57%) were non-brain-injured and 37 (43%) were brain-injured. Impaired ICCT was a predictor of in-ICU mortality after adjustment on the global Sequential Organ Failure Assessment score (SOFA) [OR (95% CI) = 2.69 (1.05-6.85); p = 0.039] and on the non-neurological SOFA components [2.67 (1.05-6.81); p = 0.040]. IPCT was more frequently delayed in the subgroup of patients who developed post-sedation AMS (24%) compared those without AMS (0%). However, this difference did not reach statistical significance (p = 0.053). Impairment rates of ICCT and IPCT were not found to be significantly different between non-brain- and brain-injured subgroups of patients. CONCLUSION: In critically ill patients receiving deep sedation, early ICCT impairment was associated with mortality. Somatosensory and brainstem auditory evoked potentials may be useful early warning indicators of brain dysfunction as well as prognostic markers in deeply sedated critically ill patients.

Brainstem response patterns in deeply-sedated critically-ill patients predict 28-day mortality.

BACKGROUND AND PURPOSE: Deep sedation is associated with acute brain dysfunction and increased mortality. We had previously shown that early-assessed brainstem reflexes may predict outcome in deeply sedated patients. The primary objective was to determine whether patterns of brainstem reflexes might predict mortality in deeply sedated patients. The secondary objective was to generate a score predicting mortality in these patients. METHODS: Observational prospective multicenter cohort study of 148 non-brain injured deeply sedated patients, defined by a Richmond Assessment sedation Scale (RASS) <-3. Brainstem reflexes and Glasgow Coma Scale were assessed within 24 hours of sedation and categorized using latent class analysis. The Full Outline Of Unresponsiveness score (FOUR) was also assessed. Primary outcome measure was 28-day mortality. A "Brainstem Responses Assessment Sedation Score" (BRASS) was generated. RESULTS: Two distinct sub-phenotypes referred as homogeneous and heterogeneous brainstem reactivity were identified (accounting for respectively 54.6% and 45.4% of patients). Homogeneous brainstem reactivity was characterized by preserved reactivity to nociceptive stimuli and a partial and topographically homogenous depression of brainstem reflexes. Heterogeneous brainstem reactivity was characterized by a loss of reactivity to nociceptive stimuli associated with heterogeneous brainstem reflexes depression. Heterogeneous sub-phenotype was a predictor of increased risk of 28-day mortality after adjustment to Simplified Acute Physiology Score-II (SAPS-II) and RASS (Odds Ratio [95% confidence interval] = 6.44 [2.63-15.8]; p<0.0001) or Sequential Organ Failure Assessment (SOFA) and RASS (OR [95%CI] = 5.02 [2.01-12.5]; p = 0.0005). The BRASS (and marginally the FOUR) predicted 28-day mortality (c-index [95%CI] = 0.69 [0.54-0.84] and 0.65 [0.49-0.80] respectively). CONCLUSION: In this prospective cohort study, around half of all deeply sedated critically ill patients displayed an early particular neurological sub-phenotype predicting 28-day mortality, which may reflect a dysfunction of the brainstem.

Comparison of the Prognostic Significance of Initial Blood Lactate and Base Deficit in Trauma Patients.

BACKGROUND: Initial blood lactate and base deficit have been shown to be prognostic biomarkers in trauma, but their respective performances have not been compared. METHODS: Blood lactate levels and base deficit were measured at admission in trauma patients in three level 1 trauma centers. This was a retrospective analysis of prospectively acquired data. The association of initial blood lactate and base deficit with mortality was tested using receiver operating characteristics curve, logistic regression using triage scores (Revised Trauma Score and Mechanism Glasgow scale and Arterial Pressure score), and Trauma Related Injury Severity Score as a reference standard. The authors also used a reclassification method. RESULTS: The authors evaluated 1,075 trauma patients (mean age, 39 ± 18 yr, with 90% blunt and 10% penetrating injuries and a mortality of 13%). At admission, blood lactate was elevated in 425 (39%) patients and base deficit was elevated in 725 (67%) patients. Blood lactate was correlated with base deficit (R = 0.54; P < 0.001). Using logistic regression, blood lactate was a better predictor of death than base deficit when considering its additional predictive value to triage scores and Trauma Related Injury Severity Score. This result was confirmed using a reclassification method but only in the subgroup of normotensive patients (n = 745). CONCLUSIONS: Initial blood lactate should be preferred to base deficit as a biologic variable in scoring systems built to assess the initial severity of trauma patients.

Long-term prognosis after out-of-hospital resuscitation of cardiac arrest in trauma patients: prehospital trauma-associated cardiac arrest.

BACKGROUND: Although prehospital cardiac arrest (CA) remains associated with poor long-term outcome, recent studies show an improvement in the survival rate after prehospital trauma associated CA (TCA). However, data on the long-term neurological outcome of TCA, particularly from physician-staffed Emergency Medical Service (EMS), are scarce, and results reported have been inconsistent. The objective of this pilot study was to evaluate the long-term outcome of patients admitted to several trauma centres after a TCA. METHODS: This study is a retrospective database review of all patients from a multicentre prospective registry that experienced a TCA and had undergone successful cardiopulmonary resuscitation (CPR) prior their admission at the trauma centre. The primary end point was neurological outcome at 6 months among patients who survived to hospital discharge. RESULTS: 88 victims of TCA underwent successful CPR and were admitted to the hospital, 90% of whom were victims of blunt trauma. Of these 88 patients, 10 patients (11%; CI 95% 6% to 19%) survived to discharge: on discharge, 9 patients displayed a GCS of 15 and Cerebral Performance Categories (CPC) 1-2 and one patient had a GCS 7 and CPC of 3. Hypoxia was the most frequent cause of CA among survivors. 6-month follow-up was achieved for 9 patients of the 10 surviving patients. The 9 patients with a good outcome on hospital discharge had a CPC of 1 or 2 6 months post discharge. All returned to their premorbid family and social settings. CONCLUSIONS: Among patients admitted to hospital after successful CPR from TCA, hypoxia as the likely aetiology of arrest carried a more favourable prognosis. Most of the patients successfully resuscitated from TCA and surviving to hospital discharge had a good neurological outcome, suggesting that prehospital resuscitation may not be futile.

Terrorist attacks in Paris: Surgical trauma experience in a referral center.

BACKGROUND: On November 13th, 2015, terrorist bomb explosions and gunshots occurred in Paris, France, with 129 people immediately killed, and more than 300 being injured. This article describes the staff organization, surgical management, and patterns of injuries in casualties who were referred to the Teaching European Hospital Georges Pompidou. METHODS: This study is a retrospective analysis of the pre-hospital response and the in-hospital response in our referral trauma center. Data for patient flow, resource use, patterns of injuries and outcomes were obtained by the review of electronic hospital records. RESULTS: Forty-one patients were referred to our center, and 22 requiring surgery were hospitalized for>24h. From November 14th at 0:41 A.M. to November 15th at 1:10 A.M., 23 surgical interventions were performed on 22 casualties. Gunshot injuries and/or shrapnel wounds were found in 45%, fractures in 45%, head trauma in 4.5%, and abdominal injuries in 14%. Soft-tissue and musculoskeletal injuries predominated in 77% of cases, peripheral nerve injury was identified in 30%. The mortality rate was 0% at last follow up. CONCLUSION: Rapid staff and logistical response, immediate access to operating rooms, and multidisciplinary surgical care delivery led to excellent short-term outcomes, with no in-hospital death and only one patient being still hospitalized 45days after the initial event.

Tree-based algorithm for prehospital triage of polytrauma patients.

BACKGROUND: There is a need for better allocation of medical resources in polytrauma, by optimizing both the over and undertriage rates. The goal of this study is to provide a new working definition for polytrauma based on the prediction of the need for specialized trauma care. METHODS: This is a prospective, observational study, performed in a specialized trauma center in Paris. All consecutive patients admitted for a trauma at a major trauma center in Paris were included in the study. The primary outcome was the need for specialized trauma care as defined by the North American consensus. The explanatory variables included basic variables collected on scene. The modeling approach relied on recursive partitioning based decision trees. Its prediction performance was evaluated both internally and externally on a validation cohort, and compared to the MGAP (Mechanism, Glasgow coma scale, Age and Arterial pressure) score. MEASUREMENTS AND MAIN RESULTS: 1160 patients were included in the analysis over a 3-year period (2012-2014), out of which 41% needed specialized trauma care as defined by the recent US guidelines. The decision tree outperformed the MGAP and reached an area under the receiver operating characteristic curve of 0.82 [0.79-0.84]. This optimal decision rule was associated with a sensitivity of 0.94 [0.92-0.96], a specificity of 0.48 [0.44-0.52]. A conservative decision rule (refer to a trauma center all patient with a predicted probability ≥0.34) would result in an undertriage rate of 5.7% and an overtriage of 52.3% (respectively 7% and 64% in the validation cohort). CONCLUSIONS: Our tree-based decision algorithm is a user-friendly and reliable alternative to the preexisting scores, which offers good performance to predict the need for specialized trauma care.

Comfort and patient-centred care without excessive sedation: the eCASH concept.

We propose an integrated and adaptable approach to improve patient care and clinical outcomes through analgesia and light sedation, initiated early during an episode of critical illness and as a priority of care. This strategy, which may be regarded as an evolution of the Pain, Agitation and Delirium guidelines, is conveyed in the mnemonic eCASH-early Comfort using Analgesia, minimal Sedatives and maximal Humane care. eCASH aims to establish optimal patient comfort with minimal sedation as the default presumption for intensive care unit (ICU) patients in the absence of recognised medical requirements for deeper sedation. Effective pain relief is the first priority for implementation of eCASH: we advocate flexible multimodal analgesia designed to minimise use of opioids. Sedation is secondary to pain relief and where possible should be based on agents that can be titrated to a prespecified target level that is subject to regular review and adjustment; routine use of benzodiazepines should be minimised. From the outset, the objective of sedation strategy is to eliminate the use of sedatives at the earliest medically justifiable opportunity. Effective analgesia and minimal sedation contribute to the larger aims of eCASH by facilitating promotion of sleep, early mobilization strategies and improved communication of patients with staff and relatives, all of which may be expected to assist rehabilitation and avoid isolation, confusion and possible long-term psychological complications of an ICU stay. eCASH represents a new paradigm for patient-centred care in the ICU. Some organizational challenges to the implementation of eCASH are identified.

General anesthetics have differential inhibitory effects on gap junction channels and hemichannels in astrocytes and neurons.

Astrocytes represent a major non-neuronal cell population actively involved in brain functions and pathologies. They express a large amount of gap junction proteins that allow communication between adjacent glial cells and the formation of glial networks. In addition, these membrane proteins can also operate as hemichannels, through which "gliotransmitters" are released, and thus contribute to neuroglial interaction. There are now reports demonstrating that alterations of astroglial gap junction communication and/or hemichannel activity impact neuronal and synaptic activity. Two decades ago we reported that several general anesthetics inhibited gap junctions in primary cultures of astrocytes (Mantz et al., (1993) Anesthesiology 78(5):892-901). As there are increasing studies investigating neuroglial interactions in anesthetized mice, we here updated this previous study by employing acute cortical slices and by characterizing the effects of general anesthetics on both astroglial gap junctions and hemichannels. As hemichannel activity is not detected in cortical astrocytes under basal conditions, we treated acute slices with the endotoxin LPS or proinflammatory cytokines to induce hemichannel activity in astrocytes, which in turn activated neuronal hemichannels. We studied two extensively used anesthetics, propofol and ketamine, and the more recently developed dexmedetomidine. We report that these drugs have differential inhibitory effects on gap junctional communication and hemichannel activity in astrocytes when used in their respective, clinically relevant concentrations, and that dexmedetomidine appears to be the least effective on both channel functions. In addition, the three anesthetics have similar effects on neuronal hemichannels. Altogether, our observations may contribute to optimizing the selection of anesthetics for in vivo animal studies.

Efficacy and safety of sedation with dexmedetomidine in critical care patients: a meta-analysis of randomized controlled trials.

INTRODUCTION: Dexmedetomidine may help physicians target a low level of sedation. Unfortunately, the impact of dexmedetomidine on major endpoints remains unclear in intensive care unit (ICU). MATERIAL AND METHODS: To evaluate the association between dexmedetomidine use with efficacy and safety outcomes, two reviewers independently identified randomized controlled trials comparing dexmedetomidine with other sedative agents in non-post-cardiac surgery critically ill patients in the PubMed and Cochrane databases. Random effects models were considered if heterogeneity was detected using the DerSimonian and Laird estimation method. Statistical heterogeneity between results was assessed by examining forest plots, confidence intervals (CI) and by using the I(2) statistic. The risk of bias was assessed using the risk of bias tool. RESULTS: This meta-analysis included 1994 patients from 16 randomized controlled trials. Comparators were lorazepam, midazolam and propofol. Dexmedetomidine was associated with a reduction in ICU length of stays (WMD=-0.304; 95% CI [-0.477, -0.132]; P=0.001), mechanical ventilation duration (WMD=-0.313, 95% CI [-0.523, -0.104]; P=0.003) and delirium incidence (RR=0.812, 95% CI [0.680, 0.968]; P=0.020). Dexmedetomidine is also associated with an increase in the incidence of bradycardia (RR=1.947, 95% CI [1.387, 2.733]; P=0.001) and hypotension (RR=1.264; 95% CI [1.013, 1.576]; P=0.038). CONCLUSIONS AND RELEVANCE: In this first meta-analysis including only randomized controlled trials related to ICU patients, dexmedetomidine was associated with a 48h reduction in ICU length of stay, mechanical ventilation duration and delirium occurrence despite a significant heterogeneity among studies. Dexmedetomidine was also associated with an increase in bradycardia and hypotension.

Early Standard Electroencephalogram Abnormalities Predict Mortality in Septic Intensive Care Unit Patients.

INTRODUCTION: Sepsis is associated with increased mortality, delirium and long-term cognitive impairment in intensive care unit (ICU) patients. Electroencephalogram (EEG) abnormalities occurring at the acute stage of sepsis may correlate with severity of brain dysfunction. Predictive value of early standard EEG abnormalities for mortality in ICU septic patients remains to be assessed. METHODS: In this prospective, single center, observational study, standard EEG was performed, analyzed and classified according to both Synek and Young EEG scales, in consecutive patients acutely admitted in ICU for sepsis. Delirium, coma and the level of sedation were assessed at the time of EEG recording; and duration of sedation, occurrence of in-ICU delirium or death were assessed during follow-up. Adjusted analyses were carried out using multiple logistic regression. RESULTS: One hundred ten patients were included, mean age 63.8 (±18.1) years, median SAPS-II score 38 (29-55). At the time of EEG recording, 46 patients (42%) were sedated and 22 (20%) suffered from delirium. Overall, 54 patients (49%) developed delirium, of which 32 (29%) in the days after EEG recording. 23 (21%) patients died in the ICU. Absence of EEG reactivity was observed in 27 patients (25%), periodic discharges (PDs) in 21 (19%) and electrographic seizures (ESZ) in 17 (15%). ICU mortality was independently associated with a delta-predominant background (OR: 3.36; 95% CI [1.08 to 10.4]), absence of EEG reactivity (OR: 4.44; 95% CI [1.37-14.3], PDs (OR: 3.24; 95% CI [1.03 to 10.2]), Synek grade ≥ 3 (OR: 5.35; 95% CI [1.66-17.2]) and Young grade > 1 (OR: 3.44; 95% CI [1.09-10.8]) after adjustment to Simplified Acute Physiology Score (SAPS-II) at admission and level of sedation. Delirium at the time of EEG was associated with ESZ in non-sedated patients (32% vs 10%, p = 0.037); with Synek grade ≥ 3 (36% vs 7%, p< 0.05) and Young grade > 1 (36% vs 17%, p< 0.001). Occurrence of delirium in the days after EEG was associated with a delta-predominant background (48% vs 15%, p = 0.001); absence of reactivity (39% vs 10%, p = 0.003), Synek grade ≥ 3 (42% vs 17%, p = 0.001) and Young grade >1 (58% vs 17%, p = 0.0001). CONCLUSIONS: In this prospective cohort of 110 septic ICU patients, early standard EEG was significantly disturbed. Absence of EEG reactivity, a delta-predominant background, PDs, Synek grade ≥ 3 and Young grade > 1 at day 1 to 3 following admission were independent predictors of ICU mortality and were associated with occurence of delirium. ESZ and PDs, found in about 20% of our patients. Their prevalence could have been higher, with a still higher predictive value, if they had been diagnosed more thoroughly using continuous EEG.

Multicenter testing of the rapid quantification of radical oxygen species in cerebrospinal fluid to diagnose bacterial meningitis.

PURPOSE: Meningitis is a serious concern after traumatic brain injury (TBI) or neurosurgery. This study tested the level of reactive oxygen species (ROS) in cerebrospinal fluid (CSF) to diagnose meningitis in febrile patients several days after trauma or surgery. METHODS: Febrile patients (temperature > 38°C) after TBI or neurosurgery were included prospectively. ROS were measured in CSF within 4 hours after sampling using luminescence in the basal state and after cell stimulation with phorbol 12-myristate 13-acetate (PMA). The study was conducted in a single-center cohort 1 (n = 54, training cohort) and then in a multicenter cohort 2 (n = 136, testing cohort) in the Intensive Care and Neurosurgery departments of two teaching hospitals. The performance of the ROS test was compared with classical CSF criteria, and a diagnostic decision for meningitis was made by two blinded experts. RESULTS: The production of ROS was higher in the CSF of meningitis patients than in non-infected CSF, both in the basal state and after PMA stimulation. In cohort 1, ROS production was associated with a diagnosis of meningitis with an AUC of 0.814 (95% confidence interval (CI) [0.684-0.820]) for steady-state and 0.818 (95% CI [0.655-0.821]) for PMA-activated conditions. The best threshold value obtained in cohort 1 was tested in cohort 2 and showed high negative predictive values and low negative likelihood ratios of 0.94 and 0.36 in the basal state, respectively, and 0.96 and 0.24 after PMA stimulation, respectively. CONCLUSION: The ROS test in CSF appeared suitable for eliminating a diagnosis of bacterial meningitis.

Sedation options for the morbidly obese intensive care unit patient: a concise survey and an agenda for development.

BACKGROUND: We offer some perspectives and commentary on the sedation of obese patients in the intensive care unit (ICU). DISCUSSION: Sedation in morbidly obese patients should conform to the same broad principles now current in ICU practice. These include a general presumption against benzodiazepines as first-line agents. Opioids should be avoided in any situation where spontaneous breathing is required. Remifentanil is the preferred agent where continuous stable opioid levels using an infusion are required, because of its lack of context-sensitive accumulation. Volatile anaesthetics may be an option for the same reason but there are no substantial, controlled demonstrations of effectiveness/safety in short-term use in the ICU setting. Propofol is a valuable resource in the morbidly obese patients but the duration of continuous sedation should not exceed 6 days, in order to avoid propofol infusion syndrome. Alpha-2 agonists offer a range of theoretically positive features for the sedation of morbidly obese patients, but at present there is a lack of pharmacokinetic data and a critical mass of high-grade clinical data. Dexmedetomidine has the attraction of not causing respiratory depression or obstructive breathing during sedation and its sympatholytic effects should help deliver stable blood pressure and heart rate. Ketamine has a poor tolerability profile in adults so its use in the ICU context is largely confined to paediatrics. CONCLUSION: None of the agents currently available is ideal for every situation encountered in the management of morbidly obese patients. This article identifies additional research needed to place sedation practice of obese patients on a more systematic footing.

Sedation and weaning from mechanical ventilation: time for 'best practice' to catch up with new realities?

Delivery of sedation in anticipation of weaning of adult patients from prolonged mechanical ventilation is an arena of critical care medicine where opinion-based practice is currently hard to avoid because robust evidence is lacking. We offer some views on this subject, hoping to stimulate debate among colleagues.

Evaluation of the performance of French physician-staffed emergency medical service in the triage of major trauma patients.

BACKGROUND: Proper prehospital triage of trauma patients is a cornerstone for the process of care of trauma patients. In France, emergency physicians perform this process according to a national triage algorithm called Vittel Triage Criteria (VTC), introduced in 2002 to help the triage decision-making process. The aim of this two-center study was to evaluate the performance of the triage process based on the VTC to identify major trauma patients in the Paris area. METHODS: This was a retrospective analysis of two cohorts. The first cohort consisted of all patients admitted between January 2011 and September 2012 in two trauma referral centers in the region of Paris (Ile de France) and allowed estimation of overtriage. Undertriage was assessed in a second cohort made up of all prehospital trauma interventions from one emergency medicine sector during the same period. Adequate triage was defined by a direct admission of patients with an Injury Severity Score (ISS) greater than 15 into one of the regional trauma centers, and undertriage was defined as an initial nonadmission to a trauma center. Overtriage was defined by an admission of patients with an ISS of 15 or lower to a trauma center. The performance of the VTC was evaluated according to a strict to-the-letter application of the VTC and termed as theoretical triage. Logistic regression was performed to identify VTC criteria able to predict major trauma. RESULTS: Among 998 admitted patients of the first cohort, 173 patients (17%) were excluded because they were not directly admitted in the first 24 hours. In the first cohort (n = 825), adequate triage was 58% and overtriage was 42%. In the second cohort (n = 190), adequate triage was 40%, overtriage was 60%, and undertriage was less than 1%. Theoretical triage generated a nonsignificantly lower overtriage and a higher undertriage compared with observed triage. The most powerful predictors of major trauma were paralysis (odds ratio [OR,] 0.09; 95% confidence interval [CI], 0.03-0.22), flail chest (OR, 0.1; 95% CI, 0.01-0.03), and Glasgow Coma Scale (GCS) score of less than 13 (OR, 0.28; 95% CI, 0.17-0.45), whereas global assessments of speed and mechanism alone were poor predictors (positive likelihood ratio, 0.92-1.4). CONCLUSION: In the Paris area, the French physician-based prehospital triage system for patients with suspicion of major trauma showed a high rate of overtriage and a low rate of undertriage. Criteria of global assessment of speed and mechanism alone were poor predictors of major trauma.