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Circulating cardiac biomarkers may improve the prediction of long-term outcomes after cardiac surgery. The authors sought to assess if cardiac biomarkers also help better predict short-term morbidity.Prospective observational study.Single academic hospital.A total of 250 patients undergoing aortic or mitral valve surgery with or without associated coronary artery bypass grafts.None MEASUREMENT AND MAIN RESULTS: Relationships between preoperative plasma concentrations of four cardiac biomarkers (sST2, Galectin-3, GDF-15, and NT-proBNP) and postoperative outcome were assessed using logistic regressions and Cox proportional hazards models. The primary outcome was a composite of 30-day mortality, an inotropic support longer than 48 hours and an initial length of stay in the intensive carefive days. Secondary outcome measures were postoperative acute kidney injury, inotropic support duration, lengths of intensive care unit and hospital stays, and 30-day and one-year mortality. No association was observed between any of the four cardiac biomarkers and the primary outcome. The preoperative levels of Galectin-3 (hazard ratio = 1.2; p0.001) and sST2 (hazard ratio = 1.01, p0.001) were significantly associated with one-year survival, and their addition to the EuroSCORE II significantly improved the prediction of one-year mortality (p0.001). Similarly, Galectin-3 was associated with postoperative acute kidney injury (odds ratio = 1.15, p = 0.001) and improved the prediction of this complication when added to the EuroSCORE II (p = 0.002).These results suggested that the ability of cardiac biomarkers to predict short-term outcome after cardiac surgery, though of interest, appears limited. Conversely, cardiac biomarkers may have the potential to refine the prediction of long-term outcome. Admittedly, all positive results were obtained on secondary outcomes and must be regarded with caution.

Objectives To investigate whether the Edmonton Frail Scale (EFS), a multidimensional frailty assessment tool, improves the prediction of 30-day or in-hospital mortality over the use of the European System for Cardiac Outcome Risk Evaluation (EuroSCORE) II alone. Design Single-center prospective observational study. Setting University hospital. Participants Patients aged 75 years or older undergoing cardiac surgery between February 2014 and May 2017. Intervention No intervention was performed. The EFS was administered the day before surgery. Measurements and Main Results The primary endpoint was 30-day or in-hospital mortality. Secondary endpoints were times to discharge from the intensive care unit (ICU) and from the hospital, discharge to a health care facility, and ability to return home by postoperative day 30. The EFS had a good discriminative ability for 30-day mortality (area under the receiver operating characteristic curve = 0.69; 95% confidence interval [CI], 0.56-0.82). Adding frailty, defined by an EFS ≥8, to the EuroSCORE II significantly improved the prediction of 30-day (p = 0.04) mortality. The integrated discrimination index was 0.03 (95% CI, 0.01-0.06, p = 0.01), meaning that the difference in predicted risk between patients who died and those who survived increased by 3% due to the addition of frailty determined by the EFS to the EuroSCORE II. Frailty also was associated significantly with a decreased cumulative probability of discharge from the ICU (p = 0.02) and an increased incidence of discharge to a health care facility (p = 0.01). Conclusion The EFS has a good predictive ability for 30-day mortality after cardiac surgery in elderly patients and improves the prediction of 30-day mortality over the use of the EuroSCORE II.

IntroductionSelf-efficacy is defined as people’s internal beliefs about their ability to have an impact on events that affect their lives. As part of the COVID-19 pandemic, we carried out in situ simulation for anaesthesiologists and operating room (OR) nurses. Simulation was focused on the recommendations on the use of specific personal protective equipment (PPE) as well as on airway management and intubation. We hypothesised that in situ procedural simulation should increase their perceived self-efficacy.MethodsBetween 16 March and 20 March 2020, 208 healthcare workers took part in in situ procedural simulation. A questionnaire was sent to participants on 21 April 2020. Six self-efficacy items related to PPE and airway manoeuvres were assessed before and after training on a Numeric Rating Scale from 0 to 10.ResultsSixty-seven participants (32%) replied to the questionnaire. The before–after comparison of the six items revealed an increase in perceived self-efficacy for each of them. A before training difference was observed between nurses, board-certified anaesthetists and trainees in anaesthesia in perceived self-efficacy for putting on (6 (3–8) vs 4.5 (2.25–6) vs 2 (0–6), p=0.007) and remove PPE (8 (5–8) vs 4.5 (3.25–6) vs 4 (1–6), p=0.009). No difference in perceived self-efficacy after training was observed between nurses, board-certified anaesthetists and trainees in anaesthesia.ConclusionsIn situ simulation improves the perceived self-efficacy of OR nurses and anaesthesiologists on specific skills related to the care of patients with COVID-19.

Summary Sleep apnoea is associated with negative outcomes following general anaesthesia. Current recommendations suggest using short‐acting anaesthetic agents in preference to standard agents to reduce this risk, but there is currently no evidence to support this. This randomised controlled triple‐blind trial tested the hypothesis that a combination of short‐acting agents (desflurane‐remifentanil) would reduce the postoperative impact of general anaesthesia on sleep apnoea severity compared with standard agents (sevoflurane‐fentanyl). Sixty patients undergoing hip arthroplasty under general anaesthesia were randomised to anaesthesia with desflurane‐remifentanil or sevoflurane‐fentanyl. Respiratory polygraphy was performed before surgery and on the first and third postoperative nights. The primary outcome was the supine apnoea‐hypopnoea index on the first postoperative night. Secondary outcomes were the supine apnoea‐hypopnoea index on the third postoperative night, and the oxygen desaturation index on the first and third postoperative nights. Additional outcomes included intravenous morphine equivalent consumption and pain scores on postoperative days 1, 2 and 3. Pre‐operative sleep study data were similar between groups. Mean (95%CI) values for the supine apnoea‐hypopnoea index on the first postoperative night were 18.9 (12.7–25.0) and 21.4 (14.2–28.7) events.h−1, respectively, in the short‐acting and standard anaesthesia groups (p = 0.64). Corresponding values on the third postoperative night were 28.1 (15.8–40.3) and 38.0 (18.3–57.6) events.h−1 (p = 0.34). Secondary sleep‐ and pain‐related outcomes were generally similar in the two groups. In conclusion, short‐acting anaesthetic agents did not reduce the impact of general anaesthesia on sleep apnoea severity compared with standard agents. These data should prompt an update of current recommendations.

Background and objectivesDifferent injection techniques for the quadratus lumborum (QL) block have been described. Data in human cadavers suggest that the transverse oblique paramedian (TOP) QL3 may reach the thoracic paravertebral space more consistently than the QL1 and QL2. However, the distribution of injectate in cadavers may differ from that in patients. Hence, we assessed the distribution of the injectate after the QL1, QL2, and TOP QL3 techniques in patients.Materials and methodsThirty-four patients scheduled for abdominal surgery received QL blocks postoperatively; 26 patients received bilateral and 8 patients received unilateral blocks. Block injections were randomly allocated to QL1, QL2, or TOP QL3 techniques (20 blocks per each technique). The injections consisted of 18 mL of ropivacaine 0.375% with 2 mL of radiopaque contrast, injected lateral or posterior to the QL muscle for the QL1 and QL2 techniques, respectively. For the TOP QL3, the injection was into the plane between the QL and psoas muscles, proximal to the L2 transverse process. Two reviewers, blinded to the allocation, reviewed three-dimensional computed tomography (3D-CT) images to assess the distribution of injectate.Results and discussionThe QL1 block spread in the transversus abdominis plane (TAP), QL2 in the TAP, and posterior aspect of the QL muscle, whereas TOP QL3 spread consistently in the anterior aspect of the QL muscle with occasional spread to the lumbar and thoracic paravertebral areas.ConclusionsThe spread of injectate after QL1, QL2, and QL3 blocks, resulted in different distribution patterns, primarily in the area of injection. The TOP QL3 did not result in consistent interfascial spread toward the thoracic paravertebral space.

Background Propofol use during sedation for colonoscopy can result in cardiopulmonary complications. Intravenous lidocaine can alleviate visceral pain and decrease propofol requirements during surgery. We tested the hypothesis that i.v. lidocaine reduces propofol requirements during colonoscopy and improves post-colonoscopy recovery. Methods Forty patients undergoing colonoscopy were included in this randomised placebo-controlled study. After titration of propofol to produce unconsciousness, patients were given i.v. lidocaine (1.5 mg kg−1 then 4 mg kg−1 h−1) or the same volume of saline. Sedation was standardised and combined propofol and ketamine. The primary endpoint was propofol requirements. Secondary endpoints were: number of oxygen desaturation episodes, endoscopists' working conditions, discharge time to the recovery room, post-colonoscopy pain, fatigue. Results Lidocaine infusion resulted in a significant reduction in propofol requirements: 58 (47) vs 121 (109) mg (P=0.02). Doses of ketamine were similar in the two groups: 19 (2) vs 20 (3) mg in the lidocaine and saline groups, respectively. Number of episodes of oxygen desaturation, endoscopists' comfort, and times for discharge to the recovery room were similar in both groups. Post-colonoscopy pain (P Conclusions Intravenous infusion of lidocaine resulted in a 50% reduction in propofol dose requirements during colonoscopy. Immediate post-colonoscopy pain and fatigue were also improved by lidocaine. Clinical trial registration NCT 02784860.

BACKGROUND: Impaired consciousness has been associated with impaired cortical signal propagation after transcranial magnetic stimulation (TMS). We hypothesised that the reduced current propagation under propofol-induced unresponsiveness is associated with changes in both feedforward and feedback connectivity across the cortical hierarchy. METHODS: Eight subjects underwent left occipital TMS coupled with high-density EEG recordings during wakefulness and propofol-induced unconsciousness. Spectral analysis was applied to responses recorded from sensors overlying six hierarchical cortical sources involved in visual processing. Dynamic causal modelling (DCM) of induced time–frequency responses and evoked response potentials were used to investigate propofol's effects on connectivity between regions. RESULTS: Sensor space analysis demonstrated that propofol reduced both induced and evoked power after TMS in occipital, parietal, and frontal electrodes. Bayesian model selection supported a DCM with hierarchical feedforward and feedback connections. DCM of induced EEG responses revealed that the primary effect of propofol was impaired feedforward responses in cross-frequency theta/alpha–gamma coupling and within frequency theta coupling (F contrast, family-wise error corrected P

Resume Une reforme de la nomenclature belge des actes medicaux est souhaitable. Elle devra etre basee sur des criteres suffisamment transparents admis par la majorite des medecins. Notre etude, bien que ne s’adressant qu’a une discipline (l’anesthesiologie), montre qu’il est possible de trouver dans les exemples etrangers des sources d’inspiration susceptibles de susciter la reflexion et la realisation de simulations utiles. Au vu des evolutions recentes, il semble que les autorites politiques belges et les organisations professionnelles ont peut-etre pris conscience de la necessite de rechercher, de maniere concertee, les fondements methodologiques permettant une restructuration en profondeur de la classification et de la tarification des actes medicaux. A partir d’un echantillon representatif des actes d’anesthesiologie realises aux blocs operatoires de 13 hopitaux (representant ± 10 % du chiffre d’affaires national rembourse en anesthesiologie), l’etude a permis de calculer, pour chaque prestation selectionnee, un score en se basant sur une donnee objective (la duree de l’anesthesie) et sur un parametre plus subjectif (la difficulte inherente a l’acte d’anesthesie) estime par consensus d’experts. Les experts ont egalement du choisir et justifier les ponderations a attribuer a chacun de ces deux parametres (duree et difficulte de l’acte).

Background Consciousness-altering anesthetic agents disturb connectivity between brain regions composing the resting-state consciousness networks (RSNs). The default mode network (DMn), executive control network, salience network (SALn), auditory network, sensorimotor network (SMn), and visual network sustain mentation. Ketamine modifies consciousness differently from other agents, producing psychedelic dreaming and no apparent interaction with the environment. The authors used functional magnetic resonance imaging to explore ketamine-induced changes in RSNs connectivity. Methods Fourteen healthy volunteers received stepwise intravenous infusions of ketamine up to loss of responsiveness. Because of agitation, data from six subjects were excluded from analysis. RSNs connectivity was compared between absence of ketamine (wake state [W1]), light ketamine sedation, and ketamine-induced unresponsiveness (deep sedation [S2]). Results Increasing the depth of ketamine sedation from W1 to S2 altered DMn and SALn connectivity and suppressed the anticorrelated activity between DMn and other brain regions. During S2, DMn connectivity, particularly between the medial prefrontal cortex and the remaining network (effect size β [95% CI]: W1 = 0.20 [0.18 to 0.22]; S2 = 0.07 [0.04 to 0.09]), and DMn anticorrelated activity (e.g., right sensory cortex: W1 = −0.07 [−0.09 to −0.04]; S2 = 0.04 [0.01 to 0.06]) were broken down. SALn connectivity was nonuniformly suppressed (e.g., left parietal operculum: W1 = 0.08 [0.06 to 0.09]; S2 = 0.05 [0.02 to 0.07]). Executive control networks, auditory network, SMn, and visual network were minimally affected. Conclusions Ketamine induces specific changes in connectivity within and between RSNs. Breakdown of frontoparietal DMn connectivity and DMn anticorrelation and sensory and SMn connectivity preservation are common to ketamine and propofol-induced alterations of consciousness.

Sleep and anesthesia entail alterations in conscious experience. Conscious experience may be absent (unconsciousness) or take the form of dreaming, a state in which sensory stimuli are not incorporated into conscious experience (disconnected consciousness). Recent work has identified features of cortical activity that distinguish conscious from unconscious states; however, less is known about how cortical activity differs between disconnected states and normal wakefulness. We employed transcranial magnetic stimulation–electroencephalography (TMS–EEG) over parietal regions across states of anesthesia and sleep to assess whether evoked oscillatory activity differed in disconnected states. We hypothesized that alpha activity, which may regulate perception of sensory stimuli, is altered in the disconnected states of rapid eye movement (REM) sleep and ketamine anesthesia. Compared to wakefulness, evoked alpha power (8–12 Hz) was decreased during disconnected consciousness. In contrast, in unconscious states of propofol anesthesia and non-REM (NREM) sleep, evoked low-gamma power (30–40 Hz) was decreased compared to wakefulness or states of disconnected consciousness. These findings were confirmed in subjects in which dream reports were obtained following serial awakenings from NREM sleep. By examining signatures of evoked cortical activity across conscious states, we identified novel evidence that suppression of evoked alpha activity may represent a promising marker of sensory disconnection.

BackgroundThe Perturbational Complexity Index (PCI) was recently introduced to assess the capacity of thalamocortical circuits to engage in complex patterns of causal interactions. While showing high accuracy in detecting consciousness in brain injured patients, PCI depends on elaborate experimental setups and offline processing and has restricted applicability to other types of brain signals beyond transcranial magnetic stimulation and high-density EEG (TMS/hd-EEG) recordings.ObjectiveWe aim to address these limitations by introducing PCIST, a fast method for estimating perturbational complexity of any given brain response signal.MethodsPCISTis based on dimensionality reduction and state transitions (ST) quantification of evoked potentials. The index was validated on a large dataset of TMS/hd-EEG recordings obtained from 108 healthy subjects and 108 brain injured patients, and tested on sparse intracranial recordings (SEEG) of 9 patients undergoing intra-cerebral single-pulse electrical stimulation (SPES).ResultsWhen calculated on TMS/hd-EEG potentials, PCISTperformed with the same accuracy as the original PCI, while improving on the previous method by being computed in less than a second and requiring a simpler set-up. In SPES/SEEG signals, the index was able to quantify a systematic reduction of intracerebral complexity during sleep, confirming the occurrence of state-dependent changes in the effective connectivity of thalamocortical circuits, as originally assessed through TMS/hd-EEG.ConclusionsPCISTrepresents a fundamental advancement towards the implementation of a reliable and fast clinical tool for the bedside assessment of consciousness as well as a general measure to explore the neuronal mechanisms of loss/recovery of brain complexity across scales and models.

Cricoid force is widely applied to decrease the risk of pulmonary aspiration and gastric antral insufflation of air during positive-pressure ventilation, yet its efficacy remains controversial. We compared manual oesophageal compression at the low left paratracheal and cricoid levels for the prevention of gastric antral air insufflation during positive-pressure ventilation by facemask in patients scheduled for elective surgery under general anaesthesia. After gaining written consent, participants were randomly allocated by sealed envelope to one of three groups: oesophageal compression by 30 N paratracheal force (paratracheal group); oesophageal compression by 30 N cricoid force (cricoid group); or no oesophageal compression (control group). Gastric insufflation of air was assessed before and after positive-pressure ventilation by ultrasound measurement of the antral cross-sectional area and/or presence of air artefacts in the antrum. The primary outcome measure was the proportion of participants with ultrasound evidence of gastric insufflation. We recruited 30 patients into each group. Before facemask ventilation, no air artefacts were visible in the antrum in any of the participants. After facemask ventilation of the participant's lungs, no air artefacts were seen in the paratracheal group, compared with six subjects in the cricoid group and eight subjects in the control group (p = 0.012). Our results suggest that oesophageal compression can be achieved by the application of manual force at the low left paratracheal level and that this is more effective than cricoid force in preventing air entry into the gastric antrum during positive-pressure ventilation by facemask.

BACKGROUND: The analgesic efficacy reported for the adductor canal block may be related to the spread of local anesthetic outside the adductor canal. METHODS: Fifteen patients undergoing knee surgery received ultrasound-guided injections of local anesthetic at the level of the adductor hiatus. Sensory-motor block and spread of contrast solution were assessed. RESULTS: Sensation was rated as “markedly diminished” or “absent” in the saphenous nerve distribution and “slightly diminished” in the sciatic nerve territory without motor deficits. Contrast solution was found in the popliteal fossa. CONCLUSIONS: The spread of injectate to the popliteal fossa may contribute to the analgesic efficacy of adductor canal block.

Venous thromboembolism events (VTE) are a common and preventable cause of postoperative complications. Interestingly, smoking and obstructive sleep apnea syndrome (OSA) affecting a large part of our population (and especially obese patients) are two underestimated predisposing factors of VTE. Many coagulation disorders favoring thromboembolism have been identified in the case of OSA and smoking and are reviewed in this article. They can be divided into two entities: endothelial dysfunction and hemostasis disorders. Interestingly OSA and smoking share common pathways to the prothrombotic state. The interactions with others comorbidities will also be discussed. This article provides pathophysiological mechanisms of the increased risk of thromboembolism in OSA patients and smokers, which should help manage these patients more adequately during the perioperative period.

A common endpoint of general anesthetics is behavioral unresponsiveness, which is commonly associated with loss of consciousness. However, subjects can become disconnected from the environment while still having conscious experiences, as demonstrated by sleep states associated with dreaming. Among anesthetics, ketamine is remarkable in that it induces profound unresponsiveness, but subjects often report "ketamine dreams" upon emergence from anesthesia. Here, we aimed at assessing consciousness during anesthesia with propofol, xenon, and ketamine, independent of behavioral responsiveness. To do so, in 18 healthy volunteers, we measured the complexity of the cortical response to transcranial magnetic stimulation (TMS)--an approach that has proven helpful in assessing objectively the level of consciousness irrespective of sensory processing and motor responses. In addition, upon emergence from anesthesia, we collected reports about conscious experiences during unresponsiveness. Both frontal and parietal TMS elicited a low-amplitude electroencephalographic (EEG) slow wave corresponding to a local pattern of cortical activation with low complexity during propofol anesthesia, a high-amplitude EEG slow wave corresponding to a global, stereotypical pattern of cortical activation with low complexity during xenon anesthesia, and a wakefulness-like, complex spatiotemporal activation pattern during ketamine anesthesia. Crucially, participants reported no conscious experience after emergence from propofol and xenon anesthesia, whereas after ketamine they reported long, vivid dreams unrelated to the external environment. These results are relevant because they suggest that brain complexity may be sensitive to the presence of disconnected consciousness in subjects who are considered unconscious based on behavioral responses.

Resume Le syndrome d’apnees et d’hypopnees obstructives du sommeil (SAHOS) est une entite pathophysiologique a part entiere. La gestion perioperatoire des patients porteurs de cette pathologie comprend, d’une part, la prevention des apnees obstructives postoperatoires, et d’autre part, la gestion des comorbidites du patient (hypertension arterielle, obesite, ischemie myocardique, troubles du rythme cardiaque et accident vasculaire cerebral). Il a ete recemment rapporte que le SAHOS est associe a un risque accru de thromboembolie perioperatoire. Nous decrivons dans cet article, sur base d’une recherche bibliographique, les recherches publiees dans ce domaine. De tres nombreuses modifications de l’homeostasie sanguine sont associees au SAHOS. Elles se repartissent en deux entites distinctes : la dysfonction endotheliale et un etat d’hypercoagulabilite. L’origine de ces perturbations reside dans la combinaison des phenomenes d’hypoxies (ischemies-reperfusions) et des micro-eveils frequents contemporains du SAHOS. Un traitement par pression d’air positive continue par voie nasale (PAPCn) corrige la majorite des anomalies et permet donc au patient de reduire son risque thromboembolique perioperatoire. Nous vous presentons un article de synthese, dans lequel l’anesthesiste-reanimateur pourra trouver une explication et une solution a ce processus pathologique.

The adductor canal block has become a common analgesic technique in patients undergoing knee arthroplasty. Dispersion of local anesthetic outside the adductor canal through interfascial layers and blockade of smaller nerves that confer innervation to the knee could contribute to the analgesic efficacy of the adductor canal block. We studied the diffusion of local anesthetic mixed with dye after injection into the adductor canal in fresh human cadavers. In all 8 legs, injectate was found in the popliteal fossa in contact with the sciatic nerve and/or popliteal blood vessels. Interfascial spread patterns were identified.

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BackgroundImpaired consciousness has been associated with impaired cortical signal propagation following transcranial magnetic stimulation (TMS). Herein we hypothesized that the reduced current propagation under propofol-induced unresponsiveness is associated with changes in both feedforward and feedback connectivity across the cortical hierarchy.MethodsEight subjects underwent left occipital TMS coupled with high-density electroencephalograph (EEG) recordings during wakefulness and propofol-induced unconsciousness. Spectral analysis was applied to responses recorded from sensors overlying six hierarchical cortical sources involved in visual processing. Dynamic causal modelling (DCM) of evoked and induced source-space responses was used to investigate propofol’s effects on connectivity between regions.ResultsPropofol produced a wideband reduction in evoked power following TMS in five out of six electrodes. Bayesian Model Selection supported a DCM with hierarchical feedforward and feedback connections to best fit the data. DCM of induced responses revealed that the primary effect of propofol was impaired feedforward responses in cross frequency theta/alpha-gamma coupling and within frequency theta coupling (F contrast, Family Wise Error corrected pConclusionsOur data suggest that propofol-induced loss of consciousness is associated with reduced evoked power and impaired hierarchical feedforward connectivity following occipital TMS.

Severe obstructive sleep apnea (sOSA) and oxygen desaturations are both risk factors for postoperative complications. In some but not all patients, sOSA is associated with frequent oxygen desaturation episodes during sleep. The aim of this retrospective study was to identify the risk factors for exhibiting oxygen desaturation in patients with sOSA.Records of 786 patients, mainly obese (Body Mass Index [mean+SD]=30.2+6.0 kg/m2), were analyzed. Univariate and multivariate analyzes were applied to identify predictive risk factors for oxygen desaturation. Prediction probability was used to test the association between potential risk factors (obesity, age, gender, smoking, alcohol consumption, and benzodiazepines use) and the combination of sOSA and oxygen desaturation. A P value0.05 was considered as statistically significant.Univariate and multivariate analyses identified five risk factors for oxygen desaturation in the whole population: age (P0.001), obesity (P0.001), benzodiazepine use (P0.001), smoking (P=0.016), and male gender (P=0.029). The same analyses applied to patients with sOSA identified two independent risk factors for oxygen desaturation: obesity (P0.001), and benzodiazepine use (P=0.017). Obesity obtains the best prediction probability [95% CI] for the combination of sOSA and oxygen desaturation: 0.74 [0.69-0.79]. A BMI49 kg/m2 was associated with a 50% probability of combining severe OSA and nocturnal oxygen desaturation.Less than 50% of patients with sOSA experience nocturnal oxygen desaturation. Obesity and daily benzodiazepine intake are independent risk factors for these patients to exhibit nocturnal oxygen desaturation. Benzodiazepine in obese patients with sOSA should, therefore, be used cautiously.

Background Intraoperative recruitment manoeuvres (RMs) combined with PEEP reverse the decrease in functional residual capacity (FRC) associated with anaesthesia and improve intraoperative oxygenation. Whether these benefits persist after operation remains unknown. We tested the hypothesis that intraoperative RMs associated with PEEP improve postoperative spirometry including FRC and reduce the incidence of postoperative hypoxaemia in morbidly obese (MO) patients undergoing laparoscopic gastric bypass. Methods After IRB approval and informed consent, 50 MO patients undergoing laparoscopic gastric bypass under volume-controlled ventilation (tidal volume 6 ml kg −1 of IBW) were randomly ventilated with either 10 cm H 2 O PEEP or with 10 cm H 2 O PEEP and one RM carried out after induction of pneumoperitoneum, and another after exsufflation. Anaesthesia and analgesia were standardized. Spirometry was assessed before operation and 24 h after surgery. Postoperative oxygenation and the apnoea–hypopnoea index (AHI) were recorded during the first postoperative night. Results Age, BMI, and STOP BANG score were similar in both groups. FRC decrease after surgery was minimal [0.15 (0.14) litre in control and 0.38 (0.19) litre in the RM group] and similar between the groups ( P =0.35). FVC, FEV 1 , mean S p O 2 , percentage of time spent with S p O 2 below 90%, and AHI did not differ significantly between the groups. Conclusions This study demonstrates that when added to a protective mechanical ventilation combining low tidal volume and high PEEP, two RMs do not improve postoperative lung function including FRC, arterial oxygenation, and the incidence of obstructive apnoea in MO patients after laparoscopic upper abdominal surgery. Clinical trial registration EudraCT 2011-000999-33.

Major clinical endpoints of general anesthesia, such as the alteration of consciousness, are achieved through effects of anesthetic agents on the central nervous system, and, more precisely, on the brain. Historically, clinicians and researchers have always been interested in quantifying and characterizing those effects through recordings of surface brain electrical activity, namely electroencephalography (EEG). Over decades of research, the complex signal has been dissected to extract its core substance, with significant advances in the interpretation of the information it may contain. Methodological, engineering, statistical, mathematical, and computer progress now furnishes advanced tools that not only allow quantification of the effects of anesthesia, but also shed light on some aspects of anesthetic mechanisms. In this article, we will review how advanced EEG serves the anesthesiologist in that respect, but will not review other intraoperative utilities that have no direct relationship with consciousness, such as monitoring of brain and spinal cord integrity. We will start with a reminder of anesthestic effects on raw EEG and its time and frequency domain components, as well as a summary of the EEG analysis techniques of use for the anesthesiologist. This will introduce the description of the use of EEG to assess the depth of the hypnotic and anti-nociceptive components of anesthesia, and its clinical utility. The last part will describe the use of EEG for the understanding of mechanisms of anesthesia-induced alteration of consciousness. We will see how, eventually in association with transcranial magnetic stimulation, it allows exploring functional cerebral networks during anesthesia. We will also see how EEG recordings during anesthesia, and their sophisticated analysis, may help corroborate current theories of mental content generation.

BACKGROUND: To reduce head movement during resting state functional magnetic resonance imaging, post-coma patients with disorders of consciousness (DOC) are frequently sedated with propofol. However, little is known about the effects of this sedation on the brain connectivity patterns in the damaged brain essential for differential diagnosis. In this study, we aimed to assess these effects. METHODS: Using resting state functional magnetic resonance imaging 3T data obtained over several years of scanning patients for diagnostic and research purposes, we employed a seed-based approach to examine resting state connectivity in higher-order (default mode, bilateral external control, and salience) and lower-order (auditory, sensorimotor, and visual) resting state networks and connectivity with the thalamus, in 20 healthy unsedated controls, 8 unsedated patients with DOC, and 8 patients with DOC sedated with propofol. The DOC groups were matched for age at onset, etiology, time spent in DOC, diagnosis, standardized behavioral assessment scores, movement intensities, and pattern of structural brain injury (as assessed with T1-based voxel-based morphometry). RESULTS: DOC were associated with severely impaired resting state network connectivity in all but the visual network. Thalamic connectivity to higher-order network regions was also reduced. Propofol administration to patients was associated with minor further decreases in thalamic and insular connectivity. CONCLUSIONS: Our findings indicate that connectivity decreases associated with propofol sedation, involving the thalamus and insula, are relatively small compared with those already caused by DOC-associated structural brain injury. Nonetheless, given the known importance of the thalamus in brain arousal, its disruption could well reflect the diminished movement obtained in these patients. However, more research is needed on this topic to fully address the research question.

Quality of life of patients at home after an enhanced recovery protocol (ERP) for surgery has been least studied especially in elderly patients.Our first 41 patients entered in the colorectal GRACE database were interviewed through telephone about their postoperative stress, fatigue, pain, difficulty in feeding, home autonomy, and satisfaction. We compared the responses of the elderly patients (70 years, n = 19) with those of the younger patients.The time between the surgery and the questionnaire was 79 ± 48 days. Early return was experienced as stressful by ±20% of the patients. Fatigue and pain were low (respectively: simple numerical scale [SNS] = 4.2 ± 3.2 and 2.5 ± 2.9). When present, pain was relieved by the prescribed treatment. One-third of the patients described some difficulty in feeding. Fifty percent of the patients felt completely autonomous when returned at home, 80% attributed the rapid recovery of autonomy to the ERP. Finally, 87% were globally satisfied (SNS: 8.5 ± 1.0). The characteristics of the 'elderly' group (77 ± 6 years) and their questionnaire responses were similar to those of the younger patients.Despite some limitations (retrospective, different time between surgery and the telephone survey), our study suggests that quality of life at home after ERP for colorectal surgery is very satisfactory for over 80% of patients. Furthermore, this study confirms that elderly patients benefit from an ERP for colorectal surgery like younger patients.

Severe obstructive sleep apnea (OSA) is an independent risk factor for perioperative complications. Clinical scores such as Snoring, Tiredness, Observed apnea, high blood Pressure, Body Mass Index (BMI) higher than 35 kg m−2, Age older than 50 years, Neck circumference larger than 40 cm, and male gender (STOP-Bang), perioperative sleep apnea prediction (P-SAP), and OSA50 have been proposed for detecting OSA. We recently proposed a new score based on morphological metrics only, the DES-OSA score. This study compared the DES-OSA score to the three other ones with regard to their ability to detect OSA. Obese patients are particularly at risk of OSA. Following informed consent and institutional review board (IRB) approval, 1584 consecutive adults were. Should the STOP-Bang be indicative of increased risk of severe OSA, the patient was referred to complementary polysomnography (PSG). Eventual already existing recent PSG data were also collected. The abilities of the four scores to predict OSA severity were compared using sensitivity, specificity, Cohen’s kappa coefficient (CKC), and area under ROC curve (AUROC) analysis. PSG was performed in 150 patients. For detecting severe OSA, OSA50 had the highest sensitivity [value (95 % CI) 0.98 (0.90–1)]. STOP-Bang was significantly less sensitive than P-SAP and OSA50. In that respect, DES-OSA was significantly more specific than the three other ones [0.75 (0.65–0.83)]. The AUROC of DES-OSA was significantly the largest [0.9 (0.84–0.95)]. The highest CKC at detecting severe OSA was 0.62 (0.49–0.74) for DES-OSA. Similar results were obtained for moderate to severe OSA prediction. DES-OSA, which is the only exclusively morphological score available, appears to surpass the three other scores in their ability to predict moderate to severe and severe OSA, at least in our setting and in our screened population. ClinicalTrial.gov NCT02051829

Contexte : Le cours de medecine palliative est dispense aux etudiants en avant-derniere annee des etudes medicales de 2e cycle par deux enseignants, un medecin generaliste et un medecin hospitalier. Ce cours est dispense depuis 10 ans selon un format traditionnel magistral. De nouveaux objectifs et de nouvelles modalites pedagogiques ont ete introduits en 2010–2011. Ce dispositif concerne 95 etudiants. But : Cet article a pour objet de decrire le dispositif pedagogique du cours d’introduction a la medecine palliative et de fin de vie. Materiel et methodes : L’objectif principal du dispositif pedagogique est l’apprentissage reflexif des etudiants. Les outils pedagogiques sont le portfolio electronique, une vignette clinique evolutive, l’accompagnement a distance de chaque etudiant par un tuteur, des cours pluridisciplinaires en presentiel. Resultats : Le dispositif a eu lieu comme prevu. Tous les etudiants ont ouvert et complete leur portfolio. Conclusions et perspectives : Le dispositif pedagogique sera reconduit l’annee academique prochaine en tenant compte des resultats de l’evaluation certificative des portfolios et de l’analyse du dispositif par les etudiants, tuteurs et enseignants.

Non-heart-beating (NHB) organ donation has become an alternative source to increase organ supply for transplantation. A NHB donation program was implemented in our institution in 2002. As in many institutions the end of life care of the NHB donor (NHBD) is terminated in the operating room (OR) to reduce warm ischemia time. Herein we have described the organization of end of life care for these patients in our institution, including the problems addressed, the solution proposed, and the remaining issues. Emphasis is given to our protocol elaborated with the different contributors of the chain of the NHB donation program. This protocol specifies the information mandatory in the medical records, the end of life care procedure, the determination of death, and the issue of organ preservation measures before NHBD death. The persisting malaise associated with NHB donation reported by OR nurses is finally documented using an anonymous questionnaire.

Background The Surgical Pleth Index (SPI) is proposed as a means to assess the balance between noxious stimulation and the anti-nociceptive effects of anaesthesia. In this study, we compared SPI, mean arterial pressure (MAP), and heart rate (HR) as a means of assessing this balance. Methods We studied a standard stimulus [head-holder insertion (HHI)] and varying remifentanil concentrations (CeREMI) in a group of patients undergoing neurosurgery. Patients receiving target-controlled infusions were randomly assigned to one of the three CeREMI (2, 4, or 6 ng ml−1), whereas propofol target was fixed at 3 µg ml−1. Steady state for both targets was achieved before HHI. Intravascular volume status (IVS) was evaluated using respiratory variations in arterial pressure. Prediction probability (Pk) and ordinal regression were used to assess SPI, MAP, and HR performance at indicating CeREMI, and the influence of IVS and chronic treatment for high arterial pressure, as possible confounding factors. Results The maximum SPI, MAP, or HR observed after HHI correctly indicated CeREMI in one of the two patients [accurate prediction rate (APR)=0.5]. When IVS and chronic treatment for high arterial pressure were taken into account, the APR was 0.6 for each individual variable and 0.8 when all of them predicted the same CeREMI. That increase in APR paralleled an increase in Pk from 0.63 to 0.89. Conclusions SPI, HR, and MAP are of comparable value at gauging noxious stimulation–CeREMI balance. Their interpretation is improved by taking account of IVS, treatment for chronic high arterial pressure, and concordance between their predictions.

Background Mechanisms of anesthesia-induced loss of consciousness remain poorly understood. Resting-state functional magnetic resonance imaging allows investigating whole-brain connectivity changes during pharmacological modulation of the level of consciousness. Methods Low-frequency spontaneous blood oxygen level-dependent fluctuations were measured in 19 healthy volunteers during wakefulness, mild sedation, deep sedation with clinical unconsciousness, and subsequent recovery of consciousness. Results Propofol-induced decrease in consciousness linearly correlates with decreased corticocortical and thalamocortical connectivity in frontoparietal networks (i.e., default- and executive-control networks). Furthermore, during propofol-induced unconsciousness, a negative correlation was identified between thalamic and cortical activity in these networks. Finally, negative correlations between default network and lateral frontoparietal cortices activity, present during wakefulness, decreased proportionally to propofol-induced loss of consciousness. In contrast, connectivity was globally preserved in low-level sensory cortices, (i.e., in auditory and visual networks across sedation stages). This was paired with preserved thalamocortical connectivity in these networks. Rather, waning of consciousness was associated with a loss of cross-modal interactions between visual and auditory networks. Conclusions Our results shed light on the functional significance of spontaneous brain activity fluctuations observed in functional magnetic resonance imaging. They suggest that propofol-induced unconsciousness could be linked to a breakdown of cerebral temporal architecture that modifies both within- and between-network connectivity and thus prevents communication between low-level sensory and higher-order frontoparietal cortices, thought to be necessary for perception of external stimuli. They emphasize the importance of thalamocortical connectivity in higher-order cognitive brain networks in the genesis of conscious perception.

University Departmentof Anaesthesia and Intensive Care Medicine, CHR de la Citadelle, Lie`ge, BelgiumBackground: Intravenous lidocaine can be used intrao-peratively for its analgesic and antihyperalgesic pro-perties but local anaesthetics may also prolong theduration of action of neuromuscular blocking agents. Wehypothesized that intravenous lidocaine would prolongthetimetorecoveryofneuromuscularfunctionaftercisatracurium.Methods: Forty-two patients were enrolled in this rando-mized, double-blind, placebo-controlled study. Before in-duction, patients were administered either a 1.5mg/kgbolus of intravenous lidocaine followed by a 2mg/kg/hinfusion or an equal volume of saline. Anaesthesia wasinduced and maintained using propofol and remifentanilinfusions. After loss of consciousness, a 0.15mg/kg bolusof cisatracurium was administered. No additional cisatra-curium injection was allowed. Neuromuscular functionwas assessed every 20s using kinemyography. The pri-mary endpoint was the time to spontaneous recovery of atrain-of-four (TOF) ratio 0.9.Results: ThetimetospontaneousrecoveryofaTOFratio 0.9 was 94 15min in the control group and98 16min in the lidocaine group (P50.27).Conclusions: No significant prolongation of spontaneousrecovery of a TOF ratio 0.9 after cisatracurium wasfound in patients receiving intravenous lidocaine.

Neuraxial anaesthesia improves tissue perfusion and tissue oxygen tension. Vasodilation induced by this technique may result in hypotension requiring the administration of vasoactive drugs. The use of peripheral vasoconstrictors might counteract the improved tissue perfusion and its potentially beneficial effects. We therefore investigated the effect of i.v. norepinephrine and ephedrine on skin perfusion using laser-Doppler flowmetry (LDF) in patients during spinal anaesthesia.Skin blood flow expressed in perfusion units (PU) provided by LDF was measured simultaneously at the foot and the manubrium levels in 44 patients during spinal anaesthesia with a sensory level below T5. Norepinephrine infusion was then titrated to normalize mean arterial pressure (MAP) in 23 patients (Group NOR). Ephedrine (max. 10 mg) was administered in 21 patients (Group EPH). Changes in relative PU were compared between the two sites of measurements in each group during drug administration. The same doses of norepinephrine were assessed in 11 normal volunteers to assure comparable vasoreactivity at the foot and manubrium levels.Spinal anaesthesia resulted in a 10% decrease in MAP (P0.001), an increase in relative PU values at the foot level (P0.001), and a decrease at the sternum level (P0.05). Norepinephrine and ephedrine produced a significant increase in relative PU values at the foot level when compared with the sternum level (NOR: P=0.02; EPH: P=0.0035). In volunteers, norepinephrine decreased cutaneous perfusion similarly at the manubrium and foot levels.Improved skin perfusion induced by spinal anaesthesia was not counteracted by the use of norepinephrine or ephedrine.

Resume Les modifications hemodynamiques et cardiovasculaires de la preeclampsie varient, entre autres, avec l’evolution de la maladie, sa severite et les eventuels traitements. En debut de grossesse, les patientes qui developperont une preeclampsie presentent une pression arterielle qui, bien que normale, est plus elevee que celle des autres femmes enceintes. De meme, leur debit cardiaque est plus eleve tandis que leurs resistances vasculaires peripheriques sont normales ou basses. Lorsque les manifestations cliniques de la maladie apparaissent, le tableau hemodynamique devient, le plus souvent, celui d’une circulation a resistances elevees et bas debit cardiaque. Parfois, cependant, il peut etre celui d’une hypercinesie circulatoire. Chez les patientes preeclamptiques, les pressions de remplissage sont le plus souvent normales bien que le volume sanguin circulant soit plus faible de 600 a 800 ml par rapport a une grossesse normale. Au cours de la preeclampsie, la fonction cardiaque est generalement preservee. La preeclampsie entraine une permeabilite capillaire exageree. Il en resulte une accentuation de l’œdeme des voies respiratoires pouvant rendre l’intubation tres difficile. L’augmentation de la permeabilite capillaire contribue egalement, parmi d’autres facteurs, a l’augmentation du risque d’œdeme pulmonaire aigu. Il n’est pas justifie d’administrer un traitement antihypertenseur aux femmes preeclamptiques presentant une hypertension moderee. Un traitement antihypertenseur doit etre initie lorsque l’hypertension est severe (PAS ≥ 160 mmHg et/ou PAD ≥ 110 mmHg) afin de reduire le risque de complications maternelles. En l’absence de comparaison objective des antihypertenseurs chez la femme preeclamptique, le principal critere de choix de la modalite du traitement antihypertenseur est l’experience du praticien. L’administration systemique d’une expansion volemique n’a pas ete demontree ameliorer les pronostics maternel et neonatal. Ce traitement doit etre reserve a certaines situations ou il est indispensable de corriger une hypovolemie. Le traitement de l’OAP survenant chez une patiente preeclamptique est symptomatique et comprend notamment l’administration de vasodilatateurs et de diuretiques. L’interet de la surveillance invasive de la PAP n’est pas demontre au cours de la preeclampsie. La surveillance echographique de la situation hemodynamique peut etre utile dans ces circonstances.

Sufentanil 5 microg and clonidine 75 microg produce a similar reduction in minimum local anaesthetic concentration of ropivacaine. The aim of the present study was to compare the side effects of two equianalgesic solutions by combining 0.2% ropivacaine with either sufentanil 5 microg or clonidine 75 microg for labour epidural analgesia.In a prospective double-blind study, 60 women at 5 cm cervical dilatation were randomly allocated to receive 0.2% ropivacaine with either sufentanil 5 microg or clonidine 75 microg to initiate labour analgesia. The analgesic efficacy and side effects of the two mixtures were compared.Onset, duration and quality of analgesia and subsequent ropivacaine consumption were similar in the two groups. Hypotension was significantly more frequent and severe with clonidine than with sufentanil (systolic blood pressure100 mmHg: 17/26 vs. 6/24, P0.05; systolic blood pressure90 mmHg: 5/26 vs. 0/24, P0.05) resulting in more frequent ephedrine administration (11/26 vs. 2/24, P0.05) and larger fluid requirements (1696 +/- 583 mL vs. 1264 +/- 407 mL, P0.05). Conversely, pruritus was more frequent with sufentanil than with clonidine (6/26 vs. 1/24, P0.05).Hypotension occurs more frequently when clonidine is added to epidural ropivacaine instead of an equianalgesic dose of sufentanil. Therefore, clonidine cannot be recommended for routine administration for labour epidural analgesia.

Resume L’interruption d’un traitement antiplaquettaire a l’occasion d’un acte chirurgical chez un patient a risque cardiovasculaire est une situation a haut risque thrombotique arteriel. Elle n’est plus systematiquement preconisee si le risque hemorragique peri-operatoire et ses consequences ne sont pas superieurs au risque thrombotique arteriel. La pratique d’une anesthesie locoregionale (ALR) chez un patient sous agent anti-agregant plaquettaire (AAP) comporte probablement un risque accru. Une breve revue des donnees publiees concernant l’impact pronostique du choix d’une technique d’ALR est ici presentee ainsi que les risques hemorragiques des differentes techniques pratiquees. Les recommandations actuellement publiees sont enoncees ainsi que quelques regles destinees a guider les praticiens pour rendre compatible la gestion des AAP et l’emploi d’une technique d’ALR dans le but d’optimiser l’evolution postoperatoire des patients a haut risque cardiovasculaire et respiratoire.

Despite major advances, emesis remains a major problem in the context of cancer chemotherapy and in the postoperative period. A better understanding of the relevant neurocircuitry, especially the central pattern generator responsible for emesis and the central role of substance P, led to the development of a new class of antiemetics: the neurokinin-1 (NK1) receptor antagonists. Aprepitant is the first NK1 receptor antagonist approved for use in postoperative nausea and vomiting, but several other compounds are currently being investigated for their potential as antiemetics in the postoperative and cancer chemotherapy settings.

Resume L’arret cardiaque requiert chez la femme enceinte des mesures specifiques de prise en charge en raison des modifications physiologiques liees a la grossesse. Le massage cardiaque doit etre effectue en decubitus lateral a 27° pour eviter les effets de la compression uterine. L’intubation doit etre rapide pour eviter une inhalation et pallier plus efficacement a une desaturation arterielle en oxygene. La pratique des cardioversions et l’administration d’adrenaline se fait selon les schemas habituels mais l’administration de bicarbonates peut majorer l’acidose fœtale. En cas de grossesse superieure a 20 semaines, l’extraction fœtale par cesarienne le plus rapidement possible est recommandee. En cas d’intoxication par les anesthesiques locaux, l’administration d’intralipides est recommandee.